Background Glioblastoma (GBM) is a devastating primary brain tumor with a highly immunosuppressive tumor microenvironment, and treatment with oncolytic viruses (OVs) has emerged as a promising strategy for these tumors. Our group constructed a new OV named Delta-24-ACT, which was based on the Delta-24-RGD platform armed with 4-1BB ligand (4-1BBL). In this study, we evaluated the antitumor effect of Delta-24-ACT alone or in combination with an immune checkpoint inhibitor (ICI) in preclinical models of glioma. Methods The in vitro effect of Delta-24-ACT was characterized through analyses of its infectivity, replication and cytotoxicity by flow cytometry, immunofluorescence (IF) and MTS assays, respectively. The antitumor effect and therapeutic mechanism were evaluated in vivo using several immunocompetent murine glioma models. The tumor microenvironment was studied by flow cytometry, immunohistochemistry and IF. Results Delta-24-ACT was able to infect and exert a cytotoxic effect on murine and human glioma cell lines. Moreover, Delta-24-ACT expressed functional 4-1BBL that was able to costimulate T lymphocytes in vitro and in vivo. Delta-24-ACT elicited a more potent antitumor effect in GBM murine models than Delta-24-RGD, as demonstrated by significant increases in median survival and the percentage of long-term survivors. Furthermore, Delta-24-ACT modulated the tumor microenvironment, which led to lymphocyte infiltration and alteration of their immune phenotype, as ...

Simple Summary: Clinical management of sarcomas is complex because they are rare and heterogeneous tumors. Management requires a coordinated multidisciplinary approach, especially in children. Genomic characterization of this complex group of tumors contributes to the identification of prognostic biomarkers and to the continued expansion of therapeutic options. In this article, we present the positive experience of two Spanish hospitals in the use of genomic analysis in the overall clinical management of sarcomas in children and young adults. We describe on a case-by-case basis how genomic analysis has contributed to both diagnosis and treatment.Genomic techniques enable diagnosis and management of children and young adults with sarcomas by identifying high-risk patients and those who may benefit from targeted therapy or participation in clinical trials. Objective: to analyze the performance of an NGS gene panel for the clinical management of pediatric sarcoma patients. We studied 53 pediatric and young adult patients diagnosed with sarcoma, from two Spanish centers. Genomic data were obtained using the Oncomine Childhood Cancer Research Assay, and categorized according to their diagnostic, predictive, or prognostic value. In 44 (83%) of the 53 patients, at least one genetic alteration was identified. In 80% of these patients, the diagnosis was obtained (n = 11) or changed (n = 9), and thus genomic data affected therapy. The most frequent initial misdiagnosis was Ewing's sarcoma, instead of myxoid liposarcoma (FUS-DDDIT3), rhabdoid soft tissue tumor (SMARCB1), or angiomatoid fibrous histiocytoma (EWSR1-CREB1). In our series, two patients had a genetic alteration with an FDA-approved targeted therapy, and 30% had at least one potentially actionable alteration. NGS-based genomic studies are useful and feasible in diagnosis and clinical management of pediatric sarcomas. Genomic characterization of these rare and heterogeneous tumors also helps in the search for prognostic biomarkers and therapeutic opportunities.

Purpose: Atypical teratoid/rhabdoid tumors (AT/RT) and central nervous system primitive neuroectodermal tumors (CNS-PNET) are pediatric brain tumors with poor survival and life-long negative side effects. Here, the aim was to characterize the efficacy and safety of the oncolytic adenovirus, Delta-24-RGD, which selectively replicates in and kills tumor cells. Experimental Design: Delta-24-RGD determinants for infection and replication were evaluated in patient expression datasets. Viral replication and cytotoxicity were assessed in vitro in a battery of CNS-PNET and AT/RT cell lines. In vivo, efficacy was determined in different orthotopic mouse models, including early and established tumor models, a disseminated AT/RT lesion model, and immunocompetent humanized mouse models (hCD34(+)-NSG-SGM3). Results: Delta-24-RGD infected and replicated efficiently in all the cell lines tested. In addition, the virus induced dose-dependent cytotoxicity [IC50 value below 1 plaque-forming unit (PFU)/cell] and the release of immunogenic markers. In vivo, a single intratumoral Delta-24-RGD injection (10(7) or 10(8) PFU) significantly increased survival and led to long-term survival in AT/RT and PNET models. Delta-24-RGD hindered the dissemination of AT/RTs and increased survival, leading to 70% of long-term survivors. Of relevance, viral administration to established tumor masses (30 days after engraftment) showed therapeutic benefit. In humanized immunocompetent models, Delta-24-RGD significantly extended the survival of mice bearing AT/RTs or PNETs (ranging from 11 to 27 days) and did not display any toxicity associated with inflammation. Immunophenotyping of Delta-24-RGD-treated tumors revealed increased CD8(+) T-cell infiltration. Conclusions: Delta-24-RGD is a feasible therapeutic option for AT/RTs and CNS-PNETs. This work constitutes the basis for potential translation to the clinical setting.

Osteosarcoma is the most frequent and aggressive bone tumor in children and adolescents, with a long-term survival rate of 30%. Interleukin-12 (IL-12) is a potent cytokine that bridges innate and adaptive immunity, triggers antiangiogenic responses, and achieves potent antitumor effects. In this work, we evaluated the antisarcoma effect of a high-capacity adenoviral vector encoding mouse IL-12. This vector harbored a mifepristone-inducible system for controlled expression of IL-12 (High-Capacity adenoviral vector enconding the EF1alpha promoter [HCA-EFZP]-IL-12). We found that local administration of the vector resulted in a reduction in the tumor burden, extended overall survival, and tumor eradication. Moreover, long-term survivors exhibited immunological memory when rechallenged with the same tumor cells. Treatment with HCA-EFZP-IL-12 also resulted in a significant decrease in lung metastasis. Immunohistochemical analyses showed profound remodeling of the osteosarcoma microenvironment with decreases in angiogenesis and macrophage and myeloid cell numbers. In summary, our data underscore the potential therapeutic value of IL-12 in the context of a drug-inducible system that allows controlled expression of this cytokine, which can trigger a potent antitumor immune response in primary and metastatic pediatric osteosarcoma.

Ovarian failure (OF) is a common cause of infertility usually diagnosed as idiopathic, with genetic causes accounting for 10-25% of cases. Whole-exome sequencing (WES) may enable identifying contributing genes and variant profiles to stratify the population into subtypes of OF. This study sought to identify a blood-based gene variant profile using accumulation of rare variants to promote precision medicine in fertility preservation programs. A case-control (n = 118, n = 32, respectively) WES study was performed in which only non-synonymous rare variants <5% minor allele frequency (MAF; in the IGSR) and coverage >= 100x were considered. A profile of 66 variants of uncertain significance was used for training an unsupervised machine learning model to separate cases from controls (97.2% sensitivity, 99.2% specificity) and stratify the population into two subtypes of OF (A and B) (93.31% sensitivity, 96.67% specificity). Model testing within the IGSR female population predicted 0.5% of women as subtype A and 2.4% as subtype B. This is the first study linking OF to the accumulation of rare variants and generates a new potential taxonomy supporting application of this approach for precision medicine in fertility preservation.

Osteosarcoma (OS) is a highly aggressive tumor characterized by malignant cells producing pathologic bone; the disease presents a natural tendency to metastasize. Genetic studies indicate that the OS genome is extremely complex, presenting signs of macro-evolution, and linear and branched patterns of clonal development. However, those studies were based on the phylogenetic reconstruction of next-generation sequencing (NGS) data, which present important limitations. Thus, testing clonal evolution in experimental models could be useful for validating this hypothesis. In the present study, lentiviral LeGO-vectors were employed to generate colorimetric red, green, blue (RGB)-marking in murine, canine, and human OS. With this strategy, we studied tumor heterogeneity and the clonal dynamics occurring in vivo in immunodeficient NOD.Cg-Prkdcscid-Il2rgtm1Wjl/SzJ (NSG) mice. Based on colorimetric label, tumor clonal composition was analyzed by confocal microscopy, flow cytometry, and different types of supervised and unsupervised clonal analyses. With this approach, we observed a consistent reduction in the clonal composition of RGB-marked tumors and identified evident clonal selection at the first passage in immunodeficient mice. Furthermore, we also demonstrated that OS could follow a neutral model of growth, where the disease is defined by the coexistence of different tumor sub-clones. Our study demonstrates the importance of rigorous testing of the selective forces in commonly used experimental models.

Purpose Early phase trials are crucial in developing innovative effective agents for childhood malignancies. We report the activity in early phase paediatric oncology trials in Spain from its beginning to the present time and incorporate longitudinal data to evaluate the trends in trial characteristics and recruitment rates. Methods Members of SEHOP were contacted to obtain information about the open trials at their institutions. The study period was split into two equal periods for analysis: 2007-2013 and 2014-2020. Results Eighty-one trials and two molecular platforms have been initiated. The number of trials has increased over the time of the study for all tumour types, with a predominance of trials available for solid tumours (66%). The number of trials addressed to tumours harbouring specific molecular alterations has doubled during the second period. The proportion of industry-sponsored compared to academic trials has increased over the same years. A total of 565 children and adolescents were included, with an increasing trend over the study period. For international trials, the median time between the first country study approval and the Spanish competent authority approval was 2 months (IQR 0-6.5). Fourteen out of 81 trials were sponsored by Spanish academic institutions. Conclusions The number of available trials, and the number of participating patients, has increased in Spain from 2007. Studies focused on molecular-specific targets are now being implemented. Barrie

Background: Tobacco is the main risk factor for developing lung cancer. Yet, some heavy smokers do not develop lung cancer at advanced ages while others develop it at young ages. Here, we assess for the first time the genetic background of these clinically relevant extreme phenotypes using whole exome sequencing (WES). Methods: We performed WES of germline DNA from heavy smokers who either developed lung adenocarcinoma at an early age ( extreme cases, n=50) or did not present lung adenocarcinoma or other tumors at an advanced age (extreme controls, n=50). We selected non-synonymous variants located in exonic regions and consensus splice sites of the genes that showed significantly different allelic frequencies between both cohorts. We validated our results in all the additional extreme cases (i.e., heavy smokers who developed lung adenocarcinoma at an early age) available from The Cancer Genome Atlas (TCGA). Results: The mean age for the extreme cases and controls was respectively 49.7 and 77.5 years. Mean tobacco consumption was 43.6 and 56.8 pack-years. We identified 619 significantly different variants between both cohorts, and we validated 108 of these in extreme cases selected from TCGA. Nine validated variants, located in relevant cancer related genes, such as PARP4, HLA-A or NQO1, among others, achieved statistical significance in the False Discovery Rate test. The most significant validated variant (P=4.48x10(-5)) was located in the tumor-suppressor gene ALPK2. Conclusions: We describe genetic variants associated with extreme phenotypes of high and low risk for the development of tobacco-induced lung adenocarcinoma. Our results and our strategy may help to identify high-risk subjects and to develop new therapeutic strategies.

This next-generation exome sequencing study investigates the frequency of pathogenic or likely pathogenic germline genetic variants in known cancer-susceptibility genes among patients with osteosarcoma. Importance Osteosarcoma, the most common malignant bone tumor in children and adolescents, occurs in a high number of cancer predisposition syndromes that are defined by highly penetrant germline mutations. The germline genetic susceptibility to osteosarcoma outside of familial cancer syndromes remains unclear. Objective To investigate the germline genetic architecture of 1244 patients with osteosarcoma. Design, Setting, and Participants Whole-exome sequencing (n = 1104) or targeted sequencing (n = 140) of the DNA of 1244 patients with osteosarcoma from 10 participating international centers or studies was conducted from April 21, 2014, to September 1, 2017. The results were compared with the DNA of 1062 individuals without cancer assembled internally from 4 participating studies who underwent comparable whole-exome sequencing and 27 & x202f;173 individuals of non-Finnish European ancestry who were identified through the Exome Aggregation Consortium (ExAC) database. In the analysis, 238 high-interest cancer-susceptibility genes were assessed followed by testing of the mutational burden across 736 additional candidate genes. Principal component analyses were used to identify 732 European patients with osteosarcoma and 994 European individuals without cancer, with outliers removed for patient-control group comparisons. Patients were subsequently compared with individuals in the ExAC group. All data were analyzed from June 1, 2017, to July 1, 2019. Main Outcomes and Measures The frequency of rare pathogenic or likely pathogenic genetic variants. Results Among 1244 patients with osteosarcoma (mean [SD] age at diagnosis, 16 [8.9] years [range, 2-80 years]; 684 patients [55.0%] were male), an analysis restricted to individuals with European ancestry indicated a significantly higher pathogenic or likely pathogenic variant burden in 238 high-interest cancer-susceptibility genes among patients with osteosarcoma compared with the control group (732 vs 994, respectively; P = 1.3 x 10(-18)). A pathogenic or likely pathogenic cancer-susceptibility gene variant was identified in 281 of 1004 patients with osteosarcoma (28.0%), of which nearly three-quarters had a variant that mapped to an autosomal-dominant gene or a known osteosarcoma-associated cancer predisposition syndrome gene. The frequency of a pathogenic or likely pathogenic cancer-susceptibility gene variant was 128 of 1062 individuals (12.1%) in the control group and 2527 of 27 & x202f;173 individuals (9.3%) in the ExAC group. A higher than expected frequency of pathogenic or likely pathogenic variants was observed in genes not previously linked to osteosarcoma (eg, CDKN2A, MEN1, VHL, POT1, APC, MSH2, and ATRX) and in the Li-Fraumeni syndrome-associated gene, TP53. Conclusions and Relevance In this study, approximately one-fourth of patients with osteosarcoma unselected for family history had a highly penetrant germline mutation requiring additional follow-up analysis and possible genetic counseling with cascade testing. Question What is the frequency of pathogenic or likely pathogenic germline genetic variants in known cancer-susceptibility genes in a large population of patients with osteosarcoma who were unselected for family history? Findings In this next-generation exome sequencing study of 1244 patients with osteosarcoma, 28.0% of patients in the discovery set carried a rare pathogenic or likely pathogenic germline variant in a cancer-susceptibility gene compared with 12.1% of individuals without cancer who were comparably sequenced and 9.3% of individuals of non-Finnish European ancestry identified through the Exome Aggregation Consortium database. Meaning A higher than expected frequency of patients with osteosarcoma carrying a pathogenic or likely pathogenic germline variant suggests germline genetic testing may be warranted for individuals with osteosarcoma.

BACKGROUND: The etiology and the molecular basis of lung adenocarcinomas (LuADs) in nonsmokers are currently unknown. Furthermore, the scarcity of available primary cultures continues to hamper our biological understanding of non-smoking-related lung adenocarcinomas (NSK-LuADs). PATIENTS AND METHODS: We established patient-derived cancer cell (PDC) cultures from metastatic NSK-LuADs, including two pairs of matched EGFR-mutant PDCs before and after resistance to tyrosine kinase inhibitors (TKIs), and then performed whole-exome and RNA sequencing to delineate their genomic architecture. For validation, we analyzed independent cohorts of primary LuADs. RESULTS: In addition to known non-smoker-associated alterations (e.g. RET, ALK, EGFR, and ERBB2), we discovered novel fusions and recurrently mutated genes, including ATF7IP, a regulator of gene expression, that was inactivated in 5% of primary LuAD cases. We also found germline mutations at dominant familiar-cancer genes, highlighting the importance of genetic predisposition in the origin of a subset of NSK-LuADs. Furthermore, there was an over-representation of inactivating alterations at RB1, mostly through complex intragenic rearrangements, in treatment-naive EGFR-mutant LuADs. Three EGFR-mutant and one EGFR-wild-type tumors acquired resistance to EGFR-TKIs and chemotherapy, respectively, and histology on re-biopsies revealed the development of small-cell lung cancer/squamous cell carcinoma (SCLC/LuSCC) transformation. These features were consistent with RB1 inactivation and acquired EGFR-T790M mutation or FGFR3-TACC3 fusion in EGFR-mutant tumors. CONCLUSIONS: We found recurrent alterations in LuADs that deserve further exploration. Our work also demonstrates that a subset of NSK-LuADs arises within cancer-predisposition syndromes. The preferential occurrence of RB1 inactivation, via complex rearrangements, found in EGFR-mutant tumors appears to favor SCLC/LuSCC transformation under growth-inhibition pressures. Thus RB1 inactivation may predict the risk of LuAD transformation to a more aggressive type of lung cancer, and may need to be considered as a part of the clinical management of NSK-LuADs patients.

Despite being a rare disease, cancer is the first cause of mortality due to disease during the paediatric age in the developed countries. The current, great increase in new treatments, such as immunotherapy, constitutes a new clinical and regulatory paradigm. Cellular immunotherapy is one of these types of immunotherapy. In particular, the advanced therapy drugs with chimeric antigen receptors in the T-lymphocytes (CAR-T), and particularly the CAR-T19 cells, has opened up a new scenario in the approach to haematology tumours like acute lymphoblastic leukaemia and the B-Cell lymphomas. The approval of tisagenlecleucel and axicabtagene ciloleucel by the regulatory authorities has led to the setting up of the National Plan for Advanced Therapies-CAR-T drugs in Spain. There is evidence of, not only the advantage of identifying the centres most suitable for their administration, but also the need for these to undergo a profound change in order that their healthcare activity is extended, in some cases, to the ability for the in-house manufacture of these types of therapies. The hospitals specialised in paediatric haematology-oncology thus have the challenge of progressing towards a healthcare model that integrates cellular immunotherapy, having the appropriate capacity to manage all aspects relative to their use, manufacture, and administration of these new treatments.

Background Ewing sarcoma (EwS) is a rare, aggressive solid tumor of childhood, adolescence and young adulthood associated with pathognomonic EWSR1-ETS fusion oncoproteins altering transcriptional regulation. Genome-wide association studies (GWAS) have identified 6 common germline susceptibility loci but have not investigated low-frequency inherited variants with minor allele frequencies below 5% due to limited genotyped cases of this rare tumor. Methods We investigated the contribution of rare and low-frequency variation to EwS susceptibility in the largest EwS genome-wide association study to date (733 EwS cases and 1,346 unaffected controls of European ancestry). Results We identified two low-frequency variants, rs112837127 and rs2296730, on chromosome 20 that were associated with EwS risk (OR = 0.186 and 2.038, respectively; P-value < 5x10(-8)) and located near previously reported common susceptibility loci. After adjusting for the most associated common variant at the locus, only rs112837127 remained a statistically significant independent signal (OR = 0.200, P-value = 5.84x10(-8)). Conclusions These findings suggest rare variation residing on common haplotypes are important contributors to EwS risk. Impact Motivate future targeted sequencing studies for a comprehensive evaluation of low-frequency and rare variation around common EwS susceptibility loci.

Background: Genomic alterations studies in cell-free DNA (cfDNA) have increasing clinical use in oncology. Nextgeneration sequencing (NGS) technology provides the most complete mutational analysis, but nowadays limited data are available related to the comparison of results reported by different platforms. Here we compare two NGS panels for cfDNA: OncomineT Pan-Cancer Cell-Free Assay (Thermo Fisher Scientific), suitable for clinical laboratories, and Guardant360 (R) (GuardantHealth), with more genes targeted but only available in an outsourcing laboratory. Methods: Peripheral blood was obtained from 16 advanced cancer patients in which Guardant360 (R) (G360) was requested as part of their clinical assistance. Blood samples were sent to be analyzed with G360 panel, and an additional blood sample was drawn to obtain and analyze cfDNA with OncomineT Pan-Cancer (OM) panel in an Ion GeneStudio S5T System. Results: cfDNA analysis globally rendered 101 mutations. Regarding the 55/101 mutations claimed to be included by manufacturers in both panels, 17 mutations were reported only by G360, 10 only by OM and 28 by both. In those coincident cases, there was a high correlation between the variant allele fractions (VAFs) calculated with each panel (r = 0.979, p < 0.01). Regarding the six actionable mutations with an FDA-approved therapy reported by G360, one was missed with OM. Also, 12 mutations with clinical trials available were reported by G360 but not by OM. Conclusions: In summary, G360 and OM can produce different mutational profile in the same sample, even in genes included in both panels, which is especially important if these mutations are potentially druggable.

Background: Glioblastoma (GBM) is the most common malignant primary brain tumor in adults. Circulating biomarkers may assist in the processes of differential diagnosis and response assessment. GBM cells release extracellular vesicles containing a subset of proteins and nucleic acids. We previously demonstrated that exosomes isolated from the serum of GBM patients had an increased expression of RNU6-1 compared to healthy subjects. In this exploratory study, we investigated the role of this small noncoding RNA as a diagnostic biomarker for GBM versus other brain lesions with some potential radiological similarities. Methods: We analyzed the expression of RNU6-1 in circulating exosomes of GBM patients (n = 18), healthy controls (n = 30), and patients with subacute stroke (n = 30), acute/subacute hemorrhage (n = 30), acute demyelinating lesions (n = 18), brain metastases (n = 21), and primary central nervous system lymphoma (PCNSL; n = 12) using digital droplet PCR. Results: Expression of RNU6-1 was significantly higher in GBM patients than in healthy controls (P = .002). RNU6-1 levels were also significantly higher in exosomes from GBM patients than from patients with non-neoplastic lesions (stroke [P = .05], hemorrhage [P = .01], demyelinating lesions [P = .019]) and PCNSL (P = .004). In contrast, no significant differences were found between patients with GBM and brain metastases (P = .573). Receiver operator characteristic curve analyses supported the role of this biomarker in differentiating GBM from subacute stroke, acute/subacute hemorrhage, acute demyelinating lesions, and PCNSL (P < .05), but again not from brain metastases (P = .575). Conclusions: Our data suggest that the expression of RNU6-1 in circulating exosomes could be useful for the differentiation of GBM from non-neoplastic brain lesions and PCNSL, but not from brain metastases.

Rothmund-Thomson syndrome (RTS) is characterized by a rash that begins in the first few months of life and eventually develops into poikiloderma. Associated symptoms are alterations in the teeth, sparse hair, thin eyebrows, lack of eyelashes, low stature, bone abnormalities, hematological illnesses, gastrointestinal disease, malnutrition, cataracts, and predisposition to cancer, principally to bone tumors and skin cancer. Diagnostic certitude is provided by a genetic study involving detection of pathogenic variants of the RECQL4 gene. We hereby present a familiar case of RTS in two siblings from a Portuguese family, both diagnosed with osteosarcoma. Genomic analysis (203 genes) of both tumors as well as germline analysis of the RECQL4 gene, thus confirming the syndrome in the family, have been performed. The relevance of clinical recognition of the hallmarks of the disease and thus early diagnosis with early intervention is highlighted.

Osteosarcoma (OS) is the most frequent primary malignant bone tumor in urgent need of better therapies. Using genetically modified mouse models (GEMMs), we demonstrate that Wnt signaling promotes c-Fos-induced OS formation via the actions of the collagen-modifying enzyme Loxl2. c-Fos/AP-1 directly regulates the expression of the Wnt ligandsWnt7bandWnt9ain OS cells through promoter binding, and Wnt7b and Wnt9a in turn promote Loxl2 expression in murine and human OS cells through the transcription factors Zeb1 and Zeb2. Concordantly, inhibition of Wnt ligand secretion by inactivating theWnt-less(Wls)gene in osteoblasts in c-Fos GEMMs either early or in a therapeutic setting reduces Loxl2 expression and progression of OS. Wls-deficient osteosarcomas proliferate less, are less mineralized and are enriched in fibroblastic cells surrounded by collagen fibers. Importantly, Loxl2 inhibition using either the pan-Lox inhibitor BAPN or a specific inducible shRNA reduces OS cell proliferation in vitro and decreases tumor growth and lung colonization in murine and human orthotopic OS transplantation models. Finally, OS development is delayed in c-Fos GEMMs treated with BAPN or with specific Loxl2 blocking antibodies. Congruently, a strong correlation between c-FOS, LOXL2 and WNT7B/WNT9A expression is observed in human OS samples, and c-FOS/LOXL2 co-expression correlates with OS aggressiveness and decreased patient survival. Therefore, therapeutic targeting of Wnt and/or Loxl2 should be considered to potentiate the inadequate current treatments for pediatric, recurrent, and metastatic OS.

BACKGROUND: Osteosarcoma is the most prevalent primary bone malignancy in children and young adults. These tumors are highly metastatic, leading to poor outcome. We previously demonstrated that Cysteine-rich protein 61 (CYR61/CCN1) expression level is correlated to osteosarcoma aggressiveness in preclinical model and in patient tumor samples. The aim of the present study was to investigate the CYR61-induced intracellular mechanisms leading to the acquisition of an invasive phenotype by osteosarcoma cells. METHODS: Modified murine and human osteosarcoma cell lines were evaluated for cell adhesion, aggregation (spheroid), motility (wound healing assay), phenotypic markers expression (RT-qPCR, western blot). Cell-derived xenograft FFPE samples and patients samples (TMA) were assessed by IHC. RESULTS: CYR61 levels controlled the expression of markers related to an Epithelial-mesenchymal transition (EMT)-like process, allowing tumor cells to migrate acquiring a competent morphology, and to be able to invade the surrounding stroma. This phenotypic shift indeed correlated with tumor grade and aggressiveness in patient samples and with the metastatic dissemination potential in cell-derived xenograft models. Unlike EGFR or PDGFR, IGF1Rß levels correlated with CYR61 and N-cadherin levels, and with the aggressiveness of osteosarcoma and overall survival. The expression levels of IGF1Rß/IGF1 axis were controlled by CYR61, and anti-IGF1 neutralizing antibody prevented the CYR61-induced phenotypic shift, aggregation, and motility abilities. CONCLUSIONS: Taken together, our study provides new evidence that CYR61 acts as a key inducing factor in the metastatic progression of osteosarcoma by playing a critical role in primary tumor dissemination, with a process associated with IGF1/IGFR stimulation. This suggests that CYR61 may represent a potential pivotal target for therapeutic management of metastases spreading in osteosarcoma, in correlation with IGF1/IGFR pathway.

Pediatric high grade gliomas (pHGG), including diffuse intrinsic pontine gliomas (DIPGs), are aggressive tumors with a dismal outcome. Radiotherapy (RT) is part of the standard of care of these tumors; however, radiotherapy only leads to a transient clinical improvement. Delta-24-RGD is a genetically engineered tumor-selective adenovirus that has shown safety and clinical efficacy in adults with recurrent gliomas. In this work, we evaluated the feasibility, safety and therapeutic efficacy of Delta-24-RGD in combination with radiotherapy in pHGGs and DIPGs models. Our results showed that the combination of Delta-24-RGD with radiotherapy was feasible and resulted in a synergistic anti-glioma effect in vitro and in vivo in pHGG and DIPG models. Interestingly, Delta-24-RGD treatment led to the downregulation of relevant DNA damage repair proteins, further sensitizing tumors cells to the effect of radiotherapy. Additionally, Delta-24-RGD/radiotherapy treatment significantly increased the trafficking of immune cells (CD3, CD4+ and CD8+) to the tumor niche compared with single treatments. In summary, administration of the Delta-24-RGD/radiotherapy combination to pHGG and DIPG models is safe and significantly increases the overall survival of mice bearing these tumors. Our data offer a rationale for the combination Delta-24-RGD/radiotherapy as a therapeutic option for children with these tumors. SIGNIFICANCE: Delta-24-RGD/radiotherapy administration is safe and significantly increases the survival of treated mice. These positive data underscore the urge to translate this approach to the clinical treatment of children with pHGG and DIPGs.

Introduction. Even though ocular refractive state is highly heritable and under strong genetic control, the identification of susceptibility genes remains a challenge. Several HGF (hepatocyte growth factor) gene variants have been associated with ocular refractive errors and corneal pathology. Purpose. Here, we assess the association of an HGF gene variant, previously reported as associated with hyperopia, and ocular biometric parameters in a multicenter Spanish cohort. Methods. An observational prospective multicenter cross-sectional study was designed, including a total of 403 unrelated subjects comprising 188 hyperopic children (5 to 17years) and 2 control groups: 52 emmetropic adolescents (13 to 17years) and 163 emmetropic young adults (18 to 28years). Each individual underwent a comprehensive eye examination including cycloplegic refraction, and topographic and ocular biometric analysis. Genomic DNA was extracted from oral swabs. HGF single nucleotide polymorphism (SNP) rs12536657 was genotyped. Genotypic, allelic, and logistic regression analyses were performed comparing the different groups. A quantitative trait association test analyzing several biometric parameters was also performed using generalized estimating equations (GEEs) adjusting for age and gender. Results. No association between rs12536657 and hyperopia was found through gender-adjusted logistic regression comparing the hyperopic children with either of the two control groups. Significant associations between mean topographic corneal curvature and rs12536657 for G/A (slope=+0.32; CI 95%: 0.04-0.60; p=0.023) and A/A (slope=+0.76; CI 95%: 0.12-1.40; p=0.020) genotypes were observed with the age- and gender-adjusted univariate GEE model. Both flat and steep corneal topographic meridians were also significantly associated with rs12536657 for the G/A and A/A genotypes. No association was found between rs12536657 and any other topographic or biometric measurements. Conclusions. Our results support a possible role for HGF gene variant rs12536657 in corneal curvature in our population. To our knowledge, this is the first multicenter quantitative trait association study of HGF genotypes and ocular biometric parameters comprising a pediatric cohort.

Sunitinib is one of the most widely used targeted therapeutics for renal cell carcinoma (RCC), but acquired resistance against targeted therapies remains a major clinical challenge. To dissect mechanisms of acquired resistance and unravel reliable predictive biomarkers for sunitinib in RCC, we sequenced the exons of 409 tumor-suppressor genes and oncogenes in paired tumor samples from an RCC patient, obtained at baseline and after development of acquired resistance to sunitinib. From newly arising mutations, we selected, using in silico prediction models, six predicted to be deleterious, located in G6PD, LRP1B, SETD2, TET2, SYNE1, and DCC. Consistently, immunoblotting analysis of lysates derived from sunitinib-desensitized RCC cells and their parental counterparts showed marked differences in the levels and expression pattern of the proteins encoded by these genes. Our further analysis demonstrates essential roles for these proteins in mediating sunitinib cytotoxicity and shows that their loss of function renders tumor cells resistant to sunitinib in vitro and in vivo. Finally, sunitinib resistance induced by continuous exposure or by inhibition of the six proteins was overcome by treatment with cabozantinib or a low-dose combination of lenvatinib and everolimus. Collectively, our results unravel novel markers of acquired resistance to sunitinib and clinically relevant approaches for overcoming this resistance in RCC.

Sunitinib is one of the most widely used targeted therapeutics for renal cell-cancer (RCC) but acquired resistance against targeted therapies remains a major clinical challenge. To dissect mechanisms of acquired resistance and unravel reliable predictive biomarkers for sunitinib in renal cell-cancer (RCC), we sequenced the exons of 409 tumor-suppressor genes and oncogenes in paired tumor samples from an RCC patient, obtained at baseline and following development of acquired resistance to sunitinib. From newly arising mutations, we selected, using in-silico prediction models, 6 predicted to be deleterious, located in G6PD, LRP1B, SETD2, TET2, SYNE1 and DCC. Consistently, immunoblotting analysis of lysates derived from sunitinib-desensitized RCC cells and their parental counterparts showed marked differences in the levels and expression pattern of the proteins encoded by these genes. Our further analysis demonstrates essential roles for these proteins in mediating sunitinib cytotoxicity and shows that their loss of function render tumor cells resistant to sunitinib in vitro and in vivo. Finally, sunitinib resistance induced by continuous exposure or by inhibition of the 6 proteins was overcome by treatment with cabozantinib or a low-dose combination of lenvatinib and everolimus. Collectively, our results unravel novel markers of acquired resistance to sunitinib and clinically relevant approaches for overcoming this resistance in RCC.

Epidermal growth factor receptor (EGFR) mutational testing in advanced non-small-cell lung cancer (NSCLC) is usually performed in tumor tissue, although cfDNA (cell-free DNA) could be an alternative. We evaluated EGFR mutations in cfDNA as a complementary tool in patients, who had already known EGFR mutations in tumor tissue and were treated with either EGFR-tyrosine kinase inhibitors (TKIs) or chemotherapy. We obtained plasma samples from 21 advanced NSCLC patients with known EGFR tumor mutations, before and during therapy with EGFR-TKIs and/or chemotherapy. cfDNA was isolated and EGFR mutations were analyzed with the multiple targeted cobas EGFR Mutation Test v2. EGFR mutations were detected at baseline in cfDNA from 57% of patients. The semiquantitative index (SQI) significantly decreased from the baseline (median = 11, IQR = 9.5-13) to the best response (median = 0, IQR = 0-0, p < 0.01), followed by a significant increase at progression (median = 11, IQR = 11-15, p < 0.01) in patients treated with either EGFR-TKIs or chemotherapy. The SQI obtained with the cobas EGFR Mutation Test v2 did not correlate with the concentration in copies/mL determined by droplet digital PCR. Resistance mutation p.T790M was observed at progression in patients with either type of treatment. In conclusion, cfDNA multiple targeted EGFR mutation analysis is useful for treatment monitoring in tissue of EGFR-positive NSCLC patients independently of the drug received.

Last advances in the treatment of pediatric tumors has led to an increase of survival rates of children affected by primitive neuroectodermal tumors, however, still a significant amount of the patients do not overcome the disease. In addition, the survivors might suffer from severe side effects caused by the current standard treatments. Oncolytic virotherapy has emerged in the last years as a promising alternative for the treatment of solid tumors. In this work, we study the anti-tumor effect mediated by the oncolytic adenovirus VCN-01 in CNS-PNET models. VCN-01 is able to infect and replicate in PNET cell cultures, leading to a cytotoxicity and immunogenic cell death. In vivo, VCN-01 increased significantly the median survival of mice and led to long-term survivors in two orthotopic models of PNETs. In summary, these results underscore the therapeutic effect ofVCN-01 for rare pediatric cancers such as PNETs, and warrants further exploration on the use of this virus to treat them.

Pediatric high-grade glioma (pHGG) and diffuse intrinsic pontine gliomas (DIPGs) are aggressive pediatric brain tumors in desperate need of a curative treatment. Oncolytic virotherapy is emerging as a solid therapeutic approach. Delta-24-RGD is a replication competent adenovirus engineered to replicate in tumor cells with an aberrant RB pathway. This virus has proven to be safe and effective in adult gliomas. Here we report that the administration of Delta-24-RGD is safe in mice and results in a significant increase in survival in immunodeficient and immunocompetent models of pHGG and DIPGs. Our results show that the Delta-24-RGD antiglioma effect is mediated by the oncolytic effect and the immune response elicited against the tumor. Altogether, our data highlight the potential of this virus as treatment for patients with these tumors. Of clinical significance, these data have led to the start of a phase I/II clinical trial at our institution for newly diagnosed DIPG (NCT03178032).

BACKGROUND: Osteosarcoma is the most common malignant bone tumor in children and young adults that produces aberrant osteoid. The aim of this study was to assess the utility of 2-deoxy-2-[18F-] fluoro-D-glucose ([18F] FDG) and sodium [18F] Fluoride (Na [18F] F) PET scans in orthotopic murine models of osteosarcoma to describe the metabolic pattern of the tumors, to detect and diagnose tumors and to evaluate the efficacy of a new treatment based in oncolytic adenoviruses. METHODS: Orthotopic osteosarcoma murine models were created by the injection of 143B and 531MII cell lines. [18F]FDG and Na [18F] F PET scans were performed 30 days (143B) and 90 days (531MII) post-injection. The antitumor effect of two doses (107 and 108 pfu) of the oncolytic adenovirus VCN-01 was evaluated in 531 MII model by [18F] FDG PET studies. [18F] FDG uptake was quantified by SUVmax and Total Lesion Glycolysis (TLG) indexes. For Na [18F] F, the ratio tumor SUVmax/hip SUVmax was calculated. PET findings were confirmed by histopathological techniques. RESULTS: The metabolic pattern of tumors was different between both orthotopic models. All tumors showed [18F] FDG uptake, with a sensitivity and specificity of 100%. The [18F] FDG uptake was significantly higher for the 143B model (p < 0.001). Sensitivity for Na [18F] F was around 70% in both models, with a specificity of 100%. 531MII tumors showed a heterogeneous Na [18F] F uptake, significantly higher than 143B tumors (p < 0.01).

Diffuse intrinsic pontine gliomas (DIPGs) are aggressive glial brain tumors that primarily affect children, for which there is no curative treatment. Median overall survival is only one year. Currently, the scientific focus is on expanding the knowledge base of the molecular biology of DIPG, and identifying effective therapies. Oncolytic adenovirus DNX-2401 is a replication-competent, genetically modified virus capable of infecting and killing glioma cells, and stimulating an anti-tumor immune response. Clinical trials evaluating intratumoral DNX-2401 in adults with recurrent glioblastoma have demonstrated that the virus has a favorable safety profile and can prolong survival. Subsequently, these results have encouraged the transition of this biologically active therapy from adults into the pediatric population. To this aim, we have designed a clinical Phase I trial for newly diagnosed pediatric DIPG to investigate the feasibility, safety, and preliminary efficacy of delivering DNX-2401 into tumors within the pons following biopsy. This case report presents a pediatric patient enrolled in this ongoing Phase I trial for children and adolescents with newly diagnosed DIPG. The case involves an 8-year-old female patient with radiologically diagnosed DIPG who underwent stereotactic tumor biopsy immediately followed by intratumoral DNX-2401 in the same biopsy track. Because there were no safety concerns or new neurological deficits, the patient was discharged 3¿days after the procedures. To our knowledge, this is the first report of intratumoral DNX-2401 for a patient with DIPG in a clinical trial. We plan to demonstrate that intratumoral delivery of an oncolytic virus following tumor biopsy for pediatric patients with DIPG is a novel and feasible approach and that DNX-2401 represents an innovative treatment for the disease.

PURPOSE: Anthracyclines are widely used chemotherapeutic drugs that can cause progressive and irreversible cardiac damage and fatal heart failure. Several genetic variants associated with anthracycline-induced cardiotoxicity (AIC) have been identified, but they explain only a small proportion of the interindividual differences in AIC susceptibility. METHODS: In this study, we evaluated the association of low-frequency variants with risk of chronic AIC using the Illumina HumanExome BeadChip array in a discovery cohort of 61 anthracycline-treated breast cancer patients with replication in a second independent cohort of 83 anthracycline-treated pediatric cancer patients, using gene-based tests (SKAT-O). RESULTS: The most significant associated gene in the discovery cohort was ETFB (electron transfer flavoprotein beta subunit) involved in mitochondrial ß-oxidation and ATP production (P = 4.16 × 10-4) and this association was replicated in an independent set of anthracycline-treated cancer patients (P = 2.81 × 10-3). Within ETFB, we found that the missense variant rs79338777 (p.Pro52Leu; c.155C > T) made the greatest contribution to the observed gene association and it was associated with increased risk of chronic AIC in the two cohorts separately and when combined (OR 9.00, P = 1.95 × 10-4, 95% CI 2.83-28.6). CONCLUSIONS: We identified and replicated a novel gene, ETFB, strongly associated with chronic AIC independently of age at tumor onset and related to anthracycline-mediated mitochondrial dysfunction. Although experimental verification and further studies in larger patient cohorts are required to confirm our finding, we demonstrated that exome array data analysis represents a valuable strategy to identify novel genes contributing to the susceptibility to chronic AIC.

Ewing sarcoma (EWS) is a pediatric cancer characterized by the EWSR1-FLI1 fusion. We performed a genome-wide association study of 733 EWS cases and 1346 unaffected individuals of European ancestry. Our study replicates previously reported susceptibility loci at 1p36.22, 10q21.3 and 15q15.1, and identifies new loci at 6p25.1, 20p11.22 and 20p11.23. Effect estimates exhibit odds ratios in excess of 1.7, which is high for cancer GWAS, and striking in light of the rarity of EWS cases in familial cancer syndromes. Expression quantitative trait locus (eQTL) analyses identify candidate genes at 6p25.1 (RREB1) and 20p11.23 (KIZ). The 20p11.22 locus is near NKX2-2, a highly overexpressed gene in EWS. Interestingly, most loci reside near GGAA repeat sequences and may disrupt binding of the EWSR1-FLI1 fusion protein. The high locus to case discovery ratio from 733 EWS cases suggests a genetic architecture in which moderate risk SNPs constitute a significant fraction of risk.

Survival rates for osteosarcoma, the most common primary bone cancer, have changed little over the past three decades and are particularly low for patients with metastatic disease. We conducted a multi-institutional genome-wide association study (GWAS) to identify germline genetic variants associated with overall survival in 632 patients with osteosarcoma, including 523 patients of European ancestry and 109 from Brazil. We conducted a time-to-event analysis and estimated hazard ratios (HR) and 95% confidence intervals (CI) using Cox proportional hazards models, with and without adjustment for metastatic disease. The results were combined across the European and Brazilian case sets using a random-effects meta-analysis. The strongest association after meta-analysis was for rs3765555 at 9p24.1, which was inversely associated with overall survival (HR¿=¿1.76; 95% CI 1.41-2.18, p¿=¿4.84 × 10-7 ). After imputation across this region, the combined analysis identified two SNPs that reached genome-wide significance. The strongest single association was with rs55933544 (HR¿=¿1.9; 95% CI 1.5-2.4; p¿=¿1.3 × 10-8 ), which localizes to the GLDC gene, adjacent to the IL33 gene and was consistent across both the European and Brazilian case sets. Using publicly available data, the risk allele was associated with lower expression of IL33 and low expression of IL33 was associated with poor survival in an independent set of patients with osteosarcoma. In conclusion, we have identified the GLDC/IL33 locus on chromosome 9p24.1 as associated with overall survival in patients with osteosarcoma. Further studies are needed to confirm this association and shed light on the biological underpinnings of this susceptibility locus.

Single nucleotide polymorphisms (SNPs) may modulate individual susceptibility to carcinogens. We designed a genome-wide association study to characterize individuals presenting extreme phenotypes of high and low risk to develop tobacco-induced non-small cell lung cancer (NSCLC), and we validated our results. We hypothesized that this strategy would enrich the frequencies of the alleles that contribute to the observed traits. We genotyped 2.37 million SNPs in 95 extreme phenotype individuals, that is: heavy smokers that either developed NSCLC at an early age (extreme cases); or did not present NSCLC at an advanced age (extreme controls), selected from a discovery set (n=3631). We validated significant SNPs in 133 additional subjects with extreme phenotypes selected from databases including >39,000 individuals. Two SNPs were validated: rs12660420 (p(combined)=5.66x10(-5); ORcombined=2.80), mapping to a noncoding transcript exon of PDE10A; and rs6835978 (p(combined)=1.02x10(-4); ORcombined=2.57), an intronic variant in ATP10D. We assessed the relevance of both proteins in early-stage NSCLC. PDE10A and ATP10D mRNA expressions correlated with survival in 821 stage I-II NSCLC patients (p=0.01 and p<0.0001). PDE10A protein expression correlated with survival in 149 patients with stage I-II NSCLC (p=0.002). In conclusion, we validated two variants associated with extreme phenotypes of high and low risk of developing tobacco-induced NSCLC. Our findings may allow to identify individuals presenting high and low risk to develop tobacco-induced NSCLC and to characterize molecular mechanisms of carcinogenesis and resistance to develop NSCLC.

Osteosarcoma (OS) is the most frequent paediatric bone cancer, responsible for 9% of all cancer-related deaths in children. In this paper, a new strategy based on delivering edelfosine (ET) in lipid nanoparticles (LN) was explored in order to target the primary tumour and eliminate metastases. The in vitro and in vivo efficacy of the free drug, drug loaded into lipid nanoparticles (ET-LN) and doxorubicin (DOX) against osteosarcoma (OS) cells was analysed. ET and ET-LN decreased the growth of OS cells in vitro in a time- and dose-dependent manner. Interestingly, the uptake of ET and ET-LN was lower when OS cells were pre-treated with DOX. In vivo studies revealed that ET and ET-LN slowed down the primary tumour growth in two OS models. However, the combination of both drugs showed no additional anti-tumour effect. Importantly, ET-LN successfully prevented the metastatic spread of OS cells from the primary tumour to the lungs. On the whole, ET-LN are a promising candidate for OS chemotherapy.

BACKGROUND: The differential diagnosis between multiple primary lung cancer (MPLC) and advanced lung cancer has traditionally relied on conventional radiology and pathology. However, the outcomes of traditional diagnostic workup are often limited, and staging is uncertain. Increasing evidence suggests that next-generation sequencing (NGS) techniques offer the possibility of comparing multiple tumors on a genomic level. OBJECTIVES: The objective of this study is to assess the clinical impact utility of targeted sequencing in patients presenting with multiple synchronous or metachronous lung tumors. MATERIALS AND METHODS: We describe the diagnostic workup conducted in a patient with three lung tumors, where we used a targeted 50-gene DNA sequencing panel (Ion AmpliSeq TM Cancer Hotspot Panel v2) to assess clonality and establish an accurate lung adenocarcinoma stage. Positive results were confirmed by pyrosequencing or Sanger sequencing. RESULTS: Three surgically resected lung tumors were submitted for targeted sequencing. The tumor from the upper right lobe was positive for a TP53 c.659A¿>¿G mutation and native for KRAS. The tumor from the upper left lobe was positive for TP53 c.725G¿>¿T and KRAS c.35G¿>¿T mutations. The tumor from the lower left lobe was positive for TP53 c.1024C¿>¿T and KRAS C.34G¿>¿T mutations. Results and reviewed literature in the field support the diagnosis of MPLC instead of a single advanced lung cancer. CONCLUSION: Targeted DNA sequencing significantly increases diagnostic accuracy in patients with multiple lung tumors. NGS panels should be available for patients presenting with multiple lung tumors.

Association studies in osteosarcoma risk found significant results in intergenic regions, suggesting that regions which do not codify for proteins could play an important role. The deregulation of microRNAs (miRNAs) has been already associated with osteosarcoma. Consequently, genetic variants affecting miRNA function could be associated with risk. This study aimed to evaluate the involvement of all genetic variants in pre-miRNAs described so far in relationship to the risk of osteosarcoma. We analyzed a total of 213 genetic variants in 206 pre-miRNAs in two cohorts of osteosarcoma patients (n¿=¿100) and their corresponding controls (n¿=¿256) from Spanish and Slovenian populations, using Goldengate Veracode technology (Illumina). Four polymorphisms in pre-miRNAs at 14q32 miRNA cluster were associated with osteosarcoma risk in the Spanish population (rs12894467, rs61992671, rs58834075 and rs12879262). Pathway enrichment analysis including target genes of these miRNAs pointed out the WNT signaling pathways overrepresented. Moreover, different single nucleotide polymorphism (SNP) effects between the two populations included were observed, suggesting the existence of population differences. In conclusion, 14q32 miRNA cluster seems to be a hotspot for osteosarcoma susceptibility in the Spanish population, but not in the Slovenian, which supports the idea of the existence of population differences in developing this disease.

BACKGROUND: Type I gastric neuroendocrine tumors (gNETs) classically arise because of hypergastrinemia and involve destruction of parietal cells, which are responsible for gastric acid secretion through the ATP4A proton pump and for intrinsic factor production. METHODS: By whole exome sequencing, we studied a family with three members with gNETs plus hypothyroidism and rheumatoid arthritis to uncover their genetic origin. RESULTS: A heterozygous missense mutation in the ATP4A gene was identified. Carriers of this variant had low ferritin and vitamin B12 levels but did not develop gNETs. A second heterozygous mutation was also uncovered (PTH1R p.E546K). Carriers exhibited hypothyroidism and one of them had rheumatoid arthritis. Gastrin activates parathyroid hormone like hormone/parathyroid hormone 1 receptor (PTH1R) signaling, which is involved in gastric cell homeostasis. Activation of parathyroid hormone/PTH1R, which is upregulated by thyrotropin in the thyroid, is also involved in RANKL expression, which regulates bone homeostasis. Thyrotropin and RANKL expression were deregulated in PTH1R mutation carriers, suggesting a link between the PTH1R gene, hypothyroidism, rheumatoid arthritis, and gastric disease. Only patients with both mutations developed gNETs plus hypothyroidism and rheumatoid arthritis. CONCLUSION: Both mutations suggest that a collaborative mechanism is operative in this family, in which mutations in these genes affect the function and viability of parietal cells and lead to the achlorhydria that drives hypergastrinemia and the formation of gNETs.

Systematic reviews on osteosarcoma have concluded that CTLA4 rs231775 AA genotype influences risk for the disease in the Chinese population. Remarkably, rs231775 shows different frequencies in different human populations. Therefore, it would be interesting to know whether this SNP is related to the risk of osteosarcoma in other populations. The present study aimed to evaluate the association between rs231775 and the susceptibility of osteosarcoma in the Spanish population. We performed an updated meta-analysis including a total of 538 cases and 623 controls. The genotypic association analyses showed that the CTLA4 rs231755 was associated with osteosarcoma susceptibility in the Spanish population. When meta-analysis was performed, the results displayed that CTLA4 rs231775 AA genotype was associated with the risk of developing osteosarcoma in all analyzed populations (OR=2.07; 95% CI: 1.48-2.89).The rs231775 AA genotype could be considered as a susceptibility marker in osteosarcoma Keywords: CTLA4, rs231775, +49A/G and osteogenic sarcoma.

Objective In this work we set to develop and to validate a new in vivo frameless orthotopic Diffuse Intrinsic Pontine Glioma (DIPG) model based in the implantation of a guide-screw system. Methods It consisted of a guide-screw also called bolt, a Hamilton syringe with a 26-gauge needle and an insulin-like 15-gauge needle. The guide screw is 2.6 mm in length and harbors a 0.5 mm central hole which accepts the needle of the Hamilton syringe avoiding a theoretical displacement during insertion. The guide-screw is fixed on the mouse skull according to the coordinates: 1 mm right to and 0.8 mm posterior to lambda. To reach the pons the Hamilton syringe is adjusted to a 6.5 mm depth using a cuff that serves as a stopper. This system allows delivering not only cells but also any kind of intratumoral chemotherapy, antibodies or gene/viral therapies. Results The guide-screw was successfully implanted in 10 immunodeficient mice and the animals were inoculated with DIPG human cell lines during the same anesthetic period. All the mice developed severe neurologic symptoms and had a median overall survival of 95 days ranging the time of death from 81 to 116 days. Histopathological analysis confirmed tumor into the pons in all animals confirming the validity of this model. Conclusion Here we presented a reproducible and frameless DIPG model that allows for rapid evaluation of tumorigenicity and efficacy of chemotherapeutic or gene therapy products delivered intratumorally to the pons.

Despite the great advances that have been made in osteosarcoma therapy during recent decades, recurrence and metastases are still the most common outcome of the primary disease. Current treatments include drugs such as doxorubicin (DOX) that produce an effective response during the initial exposure of tumor cells but sometimes induce drug resistance within a few cycles of chemotherapy. New therapeutic strategies are therefore needed to overcome this resistance. To this end, DOX was loaded into lipid nanoparticles (LN) and its efficacy was evaluated in commercial and patient-derived metastatic osteosarcoma cell lines. DOX efficacy was heavily influenced by passage number in metastatic cells, in which an overexpression of P-gp was observed. Notably, DOX-LN overcame the resistance associated with cell passage and improved DOX efficacy fivefold. Moreover, when DOX was co-administered with either free or encapsulated edelfosine (ET), a synergistic effect was observed. This higher efficacy of the combined treatment was found to be at least partially due to an increase in caspase-dependent cell death. The combination of DOX and ET is thus likely to be effective against osteosarcoma. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

Objectives Pediatric cancer survivors are a steadily growing population; however, chronic anthracycline-induced cardiotoxicity (AIC) is a serious long-term complication leading to considerable morbidity. We aimed to identify new genes and low-frequency variants influencing the susceptibility to AIC for pediatric cancer patients. Patients and methods We studied the association of variants on the Illumina HumanExome BeadChip array in 83 anthracycline-treated pediatric cancer patients. In addition to single-variant association tests, we carried out a gene-based analysis to investigate the combined effects of common and low-frequency variants to chronic AIC. Results Although no single-variant showed an association with chronic AIC that was statistically significant after correction for multiple testing, we identified a novel significant association for G protein-coupled receptor 35 (GPR35) by gene-based testing, a gene with potential roles in cardiac physiology and pathology (P = 7.0 x 10(-6)), which remained statistically significant after correction for multiple testing (P-FDR = 0.03). The greatest contribution to this observed association was made by rs12468485, a missense variant (p.Thr253Met, c.758C > T, minor allele frequency = 0.04), with the T allele associated with an increased risk of chronic AIC and more severe symptomatic cardiac manifestations at low anthracycline doses. Conclusion Using exome array data, we identified GPR35 as a novel susceptibility gene associated with chronic AIC in pediatric cancer patients. Copyright (c) 2017 Wolters Kluwer Health, Inc. All rights reserved.

Background. Osteosarcoma paediatric patients are usually treated with intra-arterial chemotherapy (QTia) which is administered directly to the tumour. This procedure exposes patients to ionizing radiation. Paediatric patients are especially sensitive to this exposure. Methods. The total amount of ionizing radiation received from QTia administration was quantified in a group of 16 osteosarcoma paediatric patients from the Clinica Universidad de Navarra. Results. The median of the total radiation received per patient was 33.4 Gy.cm(2) (IQR: 43.33 Gy.cm(2)), and the median number of procedures performed per subject was 10 (IQR: 6.5). Conclusions. The study highlights the importance of quantifying the radiation received by a group of children and adolescents affected by osteosarcoma during treatment with QTia. Long-term side effects of this radiation should be considered in paediatric patients. Currently, there are no previous studies that provide data of the amount of ionizing radiation received through this procedure.

Purpose: NKG2D ligands (NKG2DL) are expressed on various tumor types and immunosuppressive cells within tumor microenvironments, providing suitable targets for cancer therapy. Various immune cells express NKG2D receptors, including natural killer (NK) cells and CD8+ T cells. Interactions between NKG2DL and NKG2D receptors are essential for NK-cell elimination of osteosarcoma tumor-initiating cells. In this report, we used NKG2D-NKG2DL interactions to optimize an immunotherapeutic strategy against osteosarcoma. We evaluated in vitro and in vivo the safety and cytotoxic capacity against osteosarcoma cells of CD45RA(-) memory T cells expressing an NKG2D-4-1BB-CD3z chimeric antigen receptor (CAR). Experimental Design: CD45RA(-) cells from healthy donors were transduced with NKG2D CARs containing 4-1BB and CD3z signaling domains. NKG2D CAR expression was analyzed by flow cytometry. In vitro cytotoxicity of NKG2D-CAR(+) CD45RA(-) T cells against osteosarcoma was evaluated by performing conventional 4-hour europium-TDA release assays. For the in vivo orthotopic model, 531MII YFP-luc osteosarcoma cells were used as targets in NOD-scid IL2Rg(null) mice. Results: Lentiviral transduction of NKG2D-4-1BB-CD3z markedly increased NKG2D surface expression in CD45RA(-) cells. Genetic stability was preserved in transduced cells. In vitro, NKG2D-CAR+ memory T cells showed significantly increased cytolytic activity than untransduced cells against osteosarcoma cell lines, while preserving the integrity of healthy cells. NKG2DCAR(+) memory T cells had considerable antitumor activity in a mouse model of osteosarcoma, whereas untransduced T cells were ineffective. Conclusions: Our results demonstrate NKG2D-4-1BB-CD3z CAR-redirected memory T cells target NKG2DL-expressing osteosarcoma cells in vivo and in vitro and could be a promising immunotherapeutic approach for patients with osteosarcoma. (C) 2017 AACR.

BACKGROUND: There are no effective treatments for diffuse intrinsic pontine gliomas (DIPGs); these tumors cannot be surgical resected, and diagnosis is based on magnetic resonance imaging. As a result, tumor tissues for molecular studies and pathologic diagnosis are infrequent. New clinical trials are investigating novel medications and therapeutic techniques in an effort to improve treatment of patients with DIPGs. OBJECTIVE: To determine the safety, tolerability, and toxicity of an oncolytic adenovirus, DNX-2401, injected into the cerebellar peduncle in pediatric subjects with DIPG and to collect tumor samples of this type of tumor. METHODS: Phase I, single-center, uncontrolled trial. A tumor biopsy will be performed through the cerebellar peduncle, and DNX-2401 will be injected immediately after the biopsy. Standard therapy consisting of radiotherapy and chemotherapy will follow in 2 to 6 wk. EXPECTED OUTCOMES: Improvement of overall survival and quality of life in patients with DIPG and collection of tumor specimens to study the molecular profiling of these tumors. DISCUSSION: The aims of this trial are to contribute to the sample collection of DIPG and to offer treatment during the tumor tissue biopsy using the virus. If this virus works as expected, it could kill the tumor cells with no damage to healthy tissue, functioning as a targeted therapy. It is important to note that edema has not been observed with this virus in all trials performed to date. The information obtained through this and other similar studies may be useful for developing or improving new therapies in the battle against DIPG.

Genetic diagnosis is recommended for all pheochromocytoma and paraganglioma (PPGL) cases, as driver mutations are identified in approximately 80% of the cases. As the list of related genes expands, genetic diagnosis becomes more time-consuming, and targeted next-generation sequencing (NGS) has emerged as a cost-effective tool. This study aimed to optimize targeted NGS in PPGL genetic diagnostics. A workflow based on two customized targeted NGS assays was validated to study the 18 main PPGL genes in germline and frozen tumor DNA, with one of them specifically directed toward formalin-fixed, paraffin-embedded tissue. The series involved 453 unrelated PPGL patients, of whom 30 had known mutations and were used as controls. Partial screening using Sanger had been performed in 275 patients. NGS results were complemented with the study of gross deletions. NGS assay showed a sensitivity ¿99.4%, regardless of DNA source. We identified 45 variants of unknown significance and 89 pathogenic mutations, the latter being germline in 29 (7.2%) and somatic in 58 (31.7%) of the 183 tumors studied. In 37 patients previously studied by Sanger sequencing, the causal mutation could be identified. We demonstrated that both assays are an efficient and accurate alternative to conventional sequencing. Their application facilitates the study of minor PPGL genes, and enables genetic diagnoses in patients with incongruent or missing clinical data, who would otherwise be missed.

Rett syndrome (RTT) is an early-onset neurodevelopmental disorder that almost exclusively affects girls and is totally disabling. Three genes have been identified that cause RTT: MECP2, CDKL5 and FOXG1. However, the etiology of some of RTT patients still remains unknown. Recently, next generation sequencing (NGS) has promoted genetic diagnoses because of the quickness and affordability of the method. To evaluate the usefulness of NGS in genetic diagnosis, we present the genetic study of RTT-like patients using different techniques based on this technology. We studied 1577 patients with RTT-like clinical diagnoses and reviewed patients who were previously studied and thought to have RTT genes by Sanger sequencing. Genetically, 477 of 1577 patients with a RTT-like suspicion have been diagnosed. Positive results were found in 30% by Sanger sequencing, 23% with a custom panel, 24% with a commercial panel and 32% with whole exome sequencing. A genetic study using NGS allows the study of a larger number of genes associated with RTT-like symptoms simultaneously, providing genetic study of a wider group of patients as well as significantly reducing the response time and cost of the study.

Despite the recent advances in the development of antitumor therapies, the prognosis for patients with malignant gliomas remains dismal. Therapy with tumor-selective viruses is emerging as a treatment option for this devastating disease. In this study we characterize the anti-glioma effect of VCN-01, an improved hyaluronidase-armed pRB-pathway-selective oncolytic adenovirus that has proven safe and effective in the treatment of several solid tumors. VCN-01 displayed a significant cytotoxic effect on glioma cells in vitro. In vivo, in two different orthotopic glioma models, a single intra-tumoral administration of VCN-01 increased overall survival significantly and led to long-term survivors free of disease.

To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events >2¿Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases.

Using an integrated pathway-based approach, we identified polymorphisms in ABCC6, ABCB1 and CYP2C8 associated with OS. These associations were replicated in a large independent cohort, highlighting the importance of pharmacokinetic genes as prognostic markers in ES.

Osteosarcoma (OS) is the most prevalent osseous tumour in children and adolescents and, within this, lung metastases remain one of the factors associated with a dismal prognosis. At present, the genetic determinants driving pulmonary metastasis are poorly understood. We adopted a novel strategy using robust filtering analysis of transcriptomic profiling in tumour osteoblastic cell populations derived from human chemo-naive primary tumours displaying extreme phenotypes (indolent versus metastatic) to uncover predictors associated with metastasis and poor survival. We identified MGP, encoding matrix-Gla protein (MGP), a non-collagenous matrix protein previously associated with the inhibition of arterial calcification. Using different orthotopic models, we found that ectopic expression of Mgp in murine and human OS cells led to a marked increase in lung metastasis. This effect was independent of the carboxylation of glutamic acid residues required for its physiological role. Abrogation of Mgp prevented lung metastatic activity, an effect that was rescued by forced expression. Mgp levels dramatically altered endothelial adhesion, trans-endothelial migration in vitro and tumour cell extravasation ability in vivo. Furthermore, Mgp modulated metalloproteinase activities and TGFß-induced Smad2/3 phosphorylation. In the clinical setting, OS patients who developed lung metastases had high serum levels of MGP at diagnosis. Thus, MGP represents a novel adverse prognostic factor and a potential therapeutic target in OS. Microarray datasets may be found at: http://bioinfow.dep.usal.es/osteosarcoma/ Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Osteosarcoma is the most common bone cancer among those with non-hematological origin and affects mainly pediatric patients. In the last 50 years, refinements in surgical procedures, as well as the introduction of aggressive neoadjuvant and adjuvant chemotherapeutic cocktails, have increased to nearly 70% the survival rate of these patients. Despite the initial therapeutic progress the fight against osteosarcoma has not substantially improved during the last three decades, and almost 30% of the patients do not respond or recur after the standard treatment. For this group there is an urgent need to implement new therapeutic approaches. Oncolytic adenoviruses are conditionally replicative viruses engineered to selectively replicate in and kill tumor cells, while remaining quiescent in healthy cells. In the last years there have been multiple preclinical and clinical studies using these viruses as therapeutic agents in the treatment of a broad range of cancers, including osteosarcoma. In this review, we summarize some of the most relevant published literature about the use of oncolytic adenoviruses to treat human osteosarcoma tumors in subcutaneous, orthotopic and metastatic mouse models. In conclusion, up to date the preclinical studies with oncolytic adenoviruses have demonstrated that are safe and efficacious against local and metastatic osteosarcoma. Knowledge arising from phase I/II clinical trials with oncolytic adenoviruses in other tumors have shown the potential of viruses to awake the patient¿s own immune system generating a response against the tumor. Generating osteosarcoma immune-competent adenoviruses friendly models will allow to better understand this potential. Future clinical trials with oncolytic adenoviruses for osteosarcoma tumors are warranted.

These results uncover VCN-01 as a promising strategy for osteosarcoma, setting the bases to propel a phase I/II trial for kids with this disease.

Mutation analysis of epidermal growth factor receptor (EGFR) gene is essential for treatment selection in non-small cell lung cancer (NSCLC). Analysis is usually performed in tumor samples. We evaluated the clinical utility of EGFR analysis in plasma cell-free DNA (cfDNA) from patients under treatment with EGFR inhibitors. We selected 36 patients with NSCLC and EGFR-activating mutations. Blood samples were collected at baseline and during treatment with EGFR inhibitors. Wild-type EGFR, L858R, delE746-A750, and T790M mutations were quantified in cfDNA by droplet digital PCR. Stage IV patients had higher total circulating EGFR copy levels than stage I (3523 vs. 1003 copies/mL; p < 0.01). There was high agreement for activating mutations between baseline cfDNA and tumor samples, especially for L858R mutation (kappa index = 0.679; p = 0.001). In 34 % of advanced NSCLC patients, we detected mutations in cfDNA not previously detected in tumor samples and double mutations in 17 %. Patients with baseline total EGFR copy levels above the median presented decreased overall survival (OS) (341 vs. 870 days, p < 0.05) and progression-free survival (PFS) (238 vs. 783 days; p < 0.05) compared with those with total EGFR copy levels below the median. Patients with baseline concentrations of activating mutations above the median (94 copies/mL) had lower OS (317 vs. 805 days; p < 0.05) and PFS (195 vs. 724 days; p < 0.05). During follow-up, T790M resistance mutation was detected in 53 % of patients. Total and mutated EGFR analysis in cfDNA seems a relevant tool to characterize the molecular profile and prognosis of NSCLC patients harboring EGFR mutations.

Current therapies fail to cure most metastatic or recurrent bone cancer. We explored the efficacy and the pathways involved in natural killer (NK) cells' elimination of osteosarcoma (OS) cells, including tumor initiating cells (TICs), which are responsible for chemotherapy resistance, recurrence, and metastasis. The expression of ligands for NK cell receptors was studied in primary OS cell lines by flow cytometry. In vitro cytotoxicity of activated and expanded NK (NKAE) cells against OS was tested, and the pathways involved explored by using specific antibody blockade. NKAE cells' ability to target OS TICs was analyzed by flow cytometry and sphere formation assays. Spironolactone (SPIR) was tested for its ability to increase OS cells' susceptibility to NK cell lysis in vitro and in vivo. We found OS cells were susceptible to NKAE cells' lysis both in vivo and in vitro, and this cytolytic activity relied on interaction between NKG2D receptor and NKG2D ligands (NKG2DL). SPIR increased OS cells' susceptibility to lysis by NKAE cells, and could shrink the OS TICs. Our results show NKAE cells target OS cells including the TICs compartment, supporting the use of NK-cell based immunotherapies for OS.

Mitochondrial DNA (mtDNA) defects have been postulated to play an important role in the modulation and/or progression of cancer. In the past decade, a wide spectrum of mtDNA variations have been suggested as potentially sensitive and specific biomarkers for several human cancer types. In this context, single nucleotide polymorphisms (SNPs) described as protective or risk variants have been published, in particular in breast cancer, though not without controversy. Moreover, many mtDNA haplogroups have been associated with different phenotypes and diseases. We genotyped 18 SNPs, 15 of them defining European mtDNA haplogroups, including SNPs described as protective or risk variants, 7 SNPs that determine BRCA1 haplotypes and a BRCA1 intron 7 polymorphism. We included in this study 90 Caucasian unrelated women with breast cancer with familial criteria and 96 controls. Our aim was to clarify the importance of any of these SNPs, mitochondrial haplogroups and BRCA1 haplotypes in the modulation of breast cancer. We detected no significant differences in the distribution of BRCA1 haplotypes between patients and controls. Haplogroup U and the 12308G variant of mtDNA were overrepresented within the control group (p = 0.005 and p = 0.036, respectively) compared to breast cancer. Finally, we identified a significant association between the BRCA1 intron 7 polymorphism and BRCA1 haplotypes. Specifically, (TTC)6/6 and (TTC)6/7 genotypes with the seven polymorphic site cassette of "H2-like" h

Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, hl 2, on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (¿ = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (¿ = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (¿ = 0.51, SE =0.18), and bladder and lung (¿ = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.

Osteosarcoma is the most frequent primary bone tumor in the pediatric age group. Its aggressive local growth pattern and its high propensity to metastasize, mainly to the lungs, give the disease an unfavorable prognosis that has situated this disease as one of the leading causes of pediatric cancer death. Current protocols for osteosarcoma treatment are based on neo-adjuvant (pre-operatory) chemotherapy followed by surgical resection of the tumor and a new phase of adjuvant chemotherapy. Despite the progress that these protocols have made in improving the outcome of the disease, the limited access of drugs to bone tumor and metastases, their indiscriminate distribution in the organism, the high required doses that cause intolerable toxicity and the development of multidrug resistance, still represent a major challenge. Nanotechnology has emerged as a new strategy to successfully address these problems by the development of nanoscaled drug carriers that present the ability to target the drug to the tumor cells, achieving high drug concentrations in the tumor area, while decreasing its presence in healthy tissues and therefore its potential systemic toxicity. This review summarizes the different lipid nanocarriers developed to deliver first and second-line anti-osteosarcoma drugs as well as emerging agents in the treatment of this disease. Moreover, it also discusses the potential of these nanocarriers for the treatment of osteosarcoma.

Analyses of genome-wide association study (GWAS) data have revealed that detectable genetic mosaicism involving large (>2 Mb) structural autosomal alterations occurs in a fraction of individuals. We present results for a set of 24,849 genotyped individuals (total GWAS set II [TGSII]) in whom 341 large autosomal abnormalities were observed in 168 (0.68%) individuals. Merging data from the new TGSII set with data from two prior reports (the Gene-Environment Association Studies and the total GWAS set I) generated a large dataset of 127,179 individuals; we then conducted a meta-analysis to investigate the patterns of detectable autosomal mosaicism (n = 1,315 events in 925 [0.73%] individuals). Restricting to events >2 Mb in size, we observed an increase in event frequency as event size decreased. The combined results underscore that the rate of detectable mosaicism increases with age (p value = 5.5 × 10(-31)) and is higher in men (p value = 0.002) but lower in participants of African ancestry (p value = 0.003). In a subset of 47 individuals from whom serial samples were collected up to 6 years apart, complex changes were noted over time and showed an overall increase in the proportion of mosaic cells as age increased. Our large combined sample allowed for a unique ability to characterize detectable genetic mosaicism involving large structural events and strengthens the emerging evidence of non-random erosion of the genome in the aging population.

The etiologic contribution of germline genetic variation to sporadic osteosarcoma is not well understood. Osteosarcoma is a sentinel cancer of Li-Fraumeni syndrome (LFS), in which approximately 70% of families meeting the classic criteria have germline TP53 mutations. We sequenced TP53 exons in 765 osteosarcoma cases. Data were analyzed with ¿(2) tests, logistic regression, and Cox proportional hazards regression models. We observed a high frequency of young osteosarcoma cases (age <30 years) carrying a known LFS- or likely LFS-associated mutation (3.8%) or rare exonic variant (5.7%) with an overall frequency of 9.5%, compared with none in case patients age 30 years and older (P < .001). This high TP53 mutation prevalence in young osteosarcoma cases is statistically significantly greater than the previously reported prevalence of 3% (P = .0024). We identified a novel association between a TP53 rare variant and metastasis at diagnosis of osteosarcoma (rs1800372, odds ratio = 4.27, 95% confidence interval = 1.2 to 15.5, P = .026). Genetic susceptibility to young onset osteosarcoma is distinct from older adult onset osteosarcoma, with a high frequency of LFS-associated and rare exonic TP53 variants.

A total of three SNPs were associated with osteosarcoma susceptibility. Interestingly, these SNPs were located in miRNA processing genes (CNOT1, CNOT4 and SND1) which are part of the RISC complex. Among them, the association of rs11866002 in CNOT1 was nearly significant after Bonferroni correction. CONCLUSIONS: This study suggests that SNPs in RISC complex genes may be involved in osteosarcoma susceptibility, especially rs11866002 in CNOT1.

We recommend prioritising testing for germline mutations in patients with HN-PGLs and T-PGLs, and for somatic mutations in those with PCC. Biochemical secretion and SDHB-immunohistochemistry should guide genetic screening in abdominal-PGLs. Paediatric and metastatic cases should not be excluded from somatic screening.

Osteosarcoma is the most common primary malignancy of the skeleton and is prevalent in children and adolescents. Survival rates are poor and have remained stagnant owing to chemoresistance and the high propensity to form lung metastases. In this study, we used in vivo transgenic models of c-fos oncogene-induced osteosarcoma and chondrosarcoma in addition to c-Fos-inducible systems in vitro to investigate downstream signalling pathways that regulate osteosarcoma growth and metastasis. Fgfr1 (fibroblast growth factor receptor 1) was identified as a novel c-Fos/activator protein-1(AP-1)-regulated gene. Induction of c-Fos in vitro in osteoblasts and chondroblasts caused an increase in Fgfr1 RNA and FGFR1 protein expression levels that resulted in increased and sustained activation of mitogen-activated protein kinases (MAPKs), morphological transformation and increased anchorage-independent growth in response to FGF2 ligand treatment. High levels of FGFR1 protein and activated pFRS2¿ signalling were observed in murine and human osteosarcomas. Pharmacological inhibition of FGFR1 signalling blocked MAPK activation and colony growth of osteosarcoma cells in vitro. Orthotopic injection in vivo of FGFR1-silenced osteosarcoma cells caused a marked twofold to fivefold decrease in spontaneous lung metastases. Similarly, inhibition of FGFR signalling in vivo with the small-molecule inhibitor AZD4547 markedly reduced the number and size of metastatic nodules. Thus deregulated FGFR signallin

Genome-wide association studies (GWAS) have mapped risk alleles for at least 10 distinct cancers to a small region of 63 000 bp on chromosome 5p15.33. This region harbors the TERT and CLPTM1L genes; the former encodes the catalytic subunit of telomerase reverse transcriptase and the latter may play a role in apoptosis. To investigate further the genetic architecture of common susceptibility alleles in this region, we conducted an agnostic subset-based meta-analysis (association analysis based on subsets) across six distinct cancers in 34 248 cases and 45 036 controls. Based on sequential conditional analysis, we identified as many as six independent risk loci marked by common single-nucleotide polymorphisms: five in the TERT gene (Region 1: rs7726159, P = 2.10 × 10(-39); Region 3: rs2853677, P = 3.30 × 10(-36) and PConditional = 2.36 × 10(-8); Region 4: rs2736098, P = 3.87 × 10(-12) and PConditional = 5.19 × 10(-6), Region 5: rs13172201, P = 0.041 and PConditional = 2.04 × 10(-6); and Region 6: rs10069690, P = 7.49 × 10(-15) and PConditional = 5.35 × 10(-7)) and one in the neighboring CLPTM1L gene (Region 2: rs451360; P = 1.90 × 10(-18) and PConditional = 7.06 × 10(-16)). Between three and five cancers mapped to each independent locus with both risk-enhancing and protective effects. Allele-specific effects on DNA methylation were seen for a subset of risk loci, indicating that methylation and subsequent effects on gene expression may contribute to the biology of risk variants

Treatment with cisplatin-containing chemotherapy regimens causes hearing loss in 40-60% of cancer patients. It has been suggested that genetic variants in the genes encoding thiopurine S-methyltransferase (TPMT) and catechol O-methyltransferase (COMT) can predict the development of cisplatin-induced ototoxicity and may explain interindividual variability in sensitivity to cisplatin-induced hearing loss. Two recently published studies however, sought to validate these findings and showed inconsistent results. The aim of this study was to evaluate the role of polymorphisms in the TPMT and COMT genes in cisplatin-induced ototoxicity. Therefore we investigated two independent cohorts of 110 Dutch and 38 Spanish patients with osteosarcoma and performed a meta-analysis including all previously published studies resulting in a total population of 664 patients with cancer. With this largest meta-analysis performed to date, we show that the influence of TPMT and COMT on the development of cisplatin-induced hearing loss may be less important than previously suggested.

Osteosarcoma is the most common malignant bone tumor in children and adolescents. The presence of metastases and the lack of response to conventional treatment are the major adverse prognostic factors. Therefore, there is an urgent need for new treatment strategies that overcome both of these problems. Our purpose was to elucidate whether the use of the oncolytic adenovirus ¿24-RGD alone or in combination with standard chemotherapy would be effective, in vitro and in vivo, against osteosarcoma. Our results showed that ¿24-RGD exerted a potent antitumor effect against osteosarcoma cell lines that was increased by the addition of cisplatin. ¿24-RGD osteosarcoma treatment resulted in autophagy in vitro that was further enhanced when combined with cisplatin. Of importance, administration of ¿24-RGD and/or cisplatin, in novel orthotopic and two lung metastatic models in vivo resulted in a significant reduction of tumor burden meanwhile maintaining a safe toxicity profile. Together, our data underscore the potential of ¿24-RGD to become a realistic therapeutic option for primary and metastatic pediatric osteosarcoma. Moreover, this study warrants a future clinical trial to evaluate the safety and efficacy of ¿24-RGD for this devastating disease.

Methotrexate (MTX), one of the important pillars in the treatment of different forms of cancer, is associated with the development of hepatotoxicity. The 677C>T variant (rs1801133) in the methylenetetrahydrofolate reductase (MTHFR) gene might affect the development of hepatotoxicity. Results in literature are, however, contradictive. The aim of this study was to evaluate the role of the MTHFR 677C>T polymorphism in MTX-induced hepatotoxicity by analyzing a Dutch cohort of pediatric patients treated with high doses of MTX and subsequently performing a meta-analysis. Ninety-eight patients receiving 542 courses of high-dose MTX were genotyped for the MTHFR 677C>T variant. Hepatotoxicity was evaluated retrospectively according to common terminology criteria for adverse events-National Cancer Institute criteria. The influence of MTHFR 677C>T on hepatotoxicity was examined using a generalized estimating equation (GEE) analysis. A fixed-effect meta-analysis based on this and previous studies investigating the association between the MTHFR 677C>T polymorphism and uniformly coded hepatotoxicity was performed. The GEE analysis showed an increased risk of developing hepatotoxicity for T versus C allele (odds ratio (OR) 1.8; 95% confidence interval (CI) 1.0-3.2, P=0.04). This finding was not supported by the meta-analysis including seven studies and 1044 patients; the OR for the 677T versus C allele was 1.1 (95% CI 0.84-1.5, P=0.25). Heterogeneity between studies was observed, possibly r

In our series, 3R/3R polymorphism correlated with a superior OS. Also, this polymorphism, when associated to wild type EGFR, was related to a higher ORR to pemetrexed. Toxicity was not significantly correlated with a specific TS genotype.

Osteosarcoma is the most common primary bone tumor in children and adults. Despite improved prognosis, resistance to chemotherapy remains responsible for failure of osteosarcoma treatment. The identification of the molecular signals that contribute to the aberrant osteosarcoma cell growth may provide clues to develop new therapeutic strategies for chemoresistant osteosarcoma. Here we show that the expression of ErbB3 is increased in human osteosarcoma cells in vitro. Tissue microarray analysis of tissue cores from osteosarcoma patients further showed that the ErbB3 protein expression is higher in bone tumors compared to normal bone tissue, and is further increased in patients with recurrent disease or soft tissue metastasis. In murine osteosarcoma cells, silencing ErbB3 using shRNA decreased cell replication, cell migration and invasion, indicating that ErbB3 contributes to tumor cell growth and invasiveness. Furthermore, ErbB3 silencing markedly reduced tumor growth in a murine allograft model in vivo. Immunohistochemal analysis showed that the reduced tumor growth induced by ErbB3 silencing in this model resulted from decreased cell osteosarcoma cell proliferation, supporting a role of ErbB3 in bone tumor growth in vivo. Taken together, the results reveal that ErbB3 expression in human osteosarcoma correlates with tumor grade. Furthermore, silencing ErbB3 in a murine osteosarcoma model results in decreased cell growth and invasiveness in vitro, and reduced tumor growth in vivo, which supports the potential therapeutic interest of targeting ErbB3 in osteosarcoma.

Background: The molecular mechanisms that are involved in the growth and invasiveness of osteosarcoma, an aggressive and invasive primary bone tumor, are not fully understood. The transcriptional co-factor FHL2 (four and a half LIM domains protein 2) acts as an oncoprotein or as a tumor suppressor depending on the tissue context. In this study, we investigated the role of FHL2 in tumorigenesis in osteosarcoma model. Methodology/Principal Findings: Western blot analyses showed that FHL2 is expressed above normal in most human and murine osteosarcoma cells. Tissue microarray analysis revealed that FHL2 protein expression is high in human osteosarcoma and correlates with osteosarcoma aggressiveness. In murine osteosarcoma cells, FHL2 silencing using shRNA decreased canonical Wnt/beta-catenin signaling and reduced the expression of Wnt responsive genes as well as of the key Wnt molecules Wnt5a and Wnt10b. This effect resulted in inhibition of osteosarcoma cell proliferation, invasion and migration in vitro. Using xenograft experiments, we showed that FHL2 silencing markedly reduced tumor growth and lung metastasis occurence in mice. The anti-oncogenic effect of FHL2 silencing in vivo was associated with reduced cell proliferation and decreased Wnt signaling in the tumors. Conclusion/Significance: Our findings demonstrate that FHL2 acts as an oncogene in osteosarcoma cells and contributes to tumorigenesis through Wnt signaling. More importantly, FHL2 depletion greatly reduces tumor cell growth and metastasis, which raises the potential therapeutic interest of targeting FHL2 to efficiently impact primary bone tumors.

Osteosarcoma is the most common primary bone malignancy of adolescents and young adults. To better understand the genetic etiology of osteosarcoma, we performed a multistage genome-wide association study consisting of 941 individuals with osteosarcoma (cases) and 3,291 cancer-free adult controls of European ancestry. Two loci achieved genome-wide significance: a locus in the GRM4 gene at 6p21.3 (encoding glutamate receptor metabotropic 4; rs1906953; P = 8.1 × 10¿¿) and a locus in the gene desert at 2p25.2 (rs7591996 and rs10208273; P = 1.0 × 10¿¿ and 2.9 × 10¿¿, respectively). These two loci warrant further exploration to uncover the biological mechanisms underlying susceptibility to osteosarcoma.

The present study describes an optimized method for isolating peripheral blood circulating tumor cells (CTCs) and performing KRAS mutation analysis. The approach combines isolation of peripheral blood mononuclear cells and immunomagnetic labeling with CD45 and CD326 human microbeads with KRAS analysis performed with a Therascreen KRAS kit by quantitative PCR. KRAS mutations were detected in the CTCs of patients with metastatic colorectal cancer (mCRC). CTCs may represent an alternative to invasive procedures and their analysis may be representative of the current disease status of the patient. This proposed analysis may be performed in a daily clinical practice

Dravet syndrome is an epileptic encephalopathy characterized by multiple types of seizures. We report the first case of musicogenic reflex seizures in a 7-year-old male with a mutation in the SCN1A gene causing Dravet syndrome. Reflex seizures have been reported in patients with Dravet syndrome provoked by body temperature elevation, looking at visual patterns, or under intermittent photic stimulation. The case we report widens the spectrum of reflex seizures recorded in patients with Dravet syndrome. Cortical hyperexcitability of genetic origin could explain the tendency of these patients to experience reflex seizures.

Osteosarcoma is the most common primary tumor of bone occurring in children and adolescents. The histological response to chemotherapy represents a key clinical factor related to survival. We previously showed that statins exhibit antitumor effects in vitro, inducing apoptotic cell death, reducing cell migration and invasion capacities and strengthening cytotoxic effects in combination with standard drugs. Comparative transcriptomic analysis between control and statin-treated cells revealed strong expression of several genes, including metallothionein (MT) 2A. MT2A overexpression by lentiviral transduction reduced bioavailable zinc levels, an effect associated with reduced osteosarcoma cell viability and enhanced cell differentiation. In contrast, MT2A silencing did not modify cell viability but strongly inhibited expression of osteoblastic markers and differentiation process. MT2A overexpression induced chemoresistance to cytotoxic drugs through direct chelation of platinum-containing drugs and indirect action on p53 zinc-dependent activity. In contrast, abrogation of MT2A enhanced cytotoxic action of chemotherapeutic drugs on osteosarcoma cells. Finally, clinical samples derived from chemonaive biopsies revealed that tumor cells expressing low MT2A levels correspond to good prognostic (good responder patients with longer survival rate), whereas high MT2A levels were associated with adverse prognosis (poor responder patients). Taken together, these data show that MT2A contri

Bone tumors strongly influence normal tissues and stimulate bone cells for the production of cytokines supporting proliferation and abnormal survival in cancer cells. We previously reported that the proteoglycan syndecan-2 controls the activity of various cytokines and growth factors and also modulates apoptosis and response to cytotoxic agents in osteosarcoma cell lines. Here, we show that syndecan-2 has a stronger tumor suppressor activity in vivo. We identify calpain-6 as a target gene downregulated by syndecan-2 in cells and in vivo. We demonstrate that calpain-6 expression in osteosarcoma cells depends on endothelin-1, a mediator of the tumor progression in bone. Syndecan-2 overexpression alters ERK1/2, PI3K/AKT and NF?B pathways that are calpain-6-promoting signals downstream of endothelin-1. Immunohistochemical analysis shows that calpain-6 is expressed in human bone tumors and metastases. A high expression of calpain-6 was specially found in recurrent osteosarcoma. Moreover, calpain-6 levels in primary tumors were inversely related to the response to chemotherapy. Consistently, calpain-6 was increased by doxorubicin and was found to be expressed at higher levels in doxorubicin-resistant U2OS osteosarcoma-derived cells as compared to responsive cells. Inhibition of calpain-6 with shRNA resulted in decreased proliferation, increased spontaneous apoptosis and increased sensitivity to doxorubicin and also methotrexate in responsive and resistant osteosarcoma cells. Taken together, our data show that syndecan-2 exerts its pro-apoptotic function through modulation of the endothelin-1/NF?B signaling and through downregulation of calpain-6, a protective factor that contributes to abnormal cell survival. Thus, this study identifies calpain-6 as a new possible therapeutic target in chemoresistant osteosarcoma.

Ewing sarcoma, a pediatric tumor characterized by EWSR1-ETS fusions, is predominantly observed in populations of European ancestry. We performed a genome-wide association study (GWAS) of 401 French individuals with Ewing sarcoma, 684 unaffected French individuals and 3,668 unaffected individuals of European descent and living in the United States. We identified candidate risk loci at 1p36.22, 10q21 and 15q15. We replicated these loci in two independent sets of cases and controls. Joint analysis identified associations with rs9430161 (P = 1.4 × 10(-20); odds ratio (OR) = 2.2) located 25 kb upstream of TARDBP, rs224278 (P = 4.0 × 10(-17); OR = 1.7) located 5 kb upstream of EGR2 and, to a lesser extent, rs4924410 at 15q15 (P = 6.6 × 10(-9); OR = 1.5). The major risk haplotypes were less prevalent in Africans, suggesting that these loci could contribute to geographical differences in Ewing sarcoma incidence. TARDBP shares structural similarities with EWSR1 and FUS, which encode RNA binding proteins, and EGR2 is a target gene of EWSR1-ETS. Variants at these loci were associated with expression levels of TARDBP, ADO (encoding cysteamine dioxygenase) and EGR2.

BACKGROUND: The cortactin (CTTN) gene has been found, by transcriptomic profiling, to be overexpressed in pediatric osteosarcoma. The location of CTTN at 11q13 and the role of cortactin in cytoskeleton restructuring make CTTN of interest as a potential biomarker for osteosarcoma. MATERIALS AND METHODS: Osteoblasts were isolated from 20 high-grade osteosarcomas before chemotherapy, and paired with cell samples from normal tissue, prior to RNA expression analysis on HG-U133A chips (Affymetrix). Semiquantitative CTTN mRNA expression was analyzed by real-time PCR. An osteosarcoma tissue microarray (TMA) containing 233 tissue spots from 48 patients was used for an immunohistochemical (IHC) study of cortactin. RESULTS: Transcriptomic profiling and real-time PCR analysis indicated increased CTTN expression in osteosarcomas (p = 0.001, Student's T test). TMA IHC showed cortactin to be present more frequently and in greater abundance in osteosarcomas than non-tumoral osteoblastic samples (p< 0.006, Mann-Withney test). Analysis of clinical outcomes indicated that overall survival for patients with primary tumors positive for cortactin was significantly lower than that for patients with cortactin negative (or only weakly staining) tumors (p = 0.0278, Log-rank test). CONCLUSIONS: Our preliminary data support the hypothesis that over-expression of cortactin, contained in the 11q13 amplicon, is involved in osteosarcoma carcinogenesis. The potential of cortactin overexpression as a biom

In an analysis of 31,717 cancer cases and 26,136 cancer-free controls from 13 genome-wide association studies, we observed large chromosomal abnormalities in a subset of clones in DNA obtained from blood or buccal samples. We observed mosaic abnormalities, either aneuploidy or copy-neutral loss of heterozygosity, of >2 Mb in size in autosomes of 517 individuals (0.89%), with abnormal cell proportions of between 7% and 95%. In cancer-free individuals, frequency increased with age, from 0.23% under 50 years to 1.91% between 75 and 79 years (P = 4.8 × 10(-8)). Mosaic abnormalities were more frequent in individuals with solid tumors (0.97% versus 0.74% in cancer-free individuals; odds ratio (OR) = 1.25; P = 0.016), with stronger association with cases who had DNA collected before diagnosis or treatment (OR = 1.45; P = 0.0005). Detectable mosaicism was also more common in individuals for whom DNA was collected at least 1 year before diagnosis with leukemia compared to cancer-free individuals (OR = 35.4; P = 3.8 × 10(-11)). These findings underscore the time-dependent nature of somatic events in the etiology of cancer and potentially other late-onset diseases.

Background: As marker genes for bipolar disorder (BP) and attention deficit hyperactivity disorder (ADHD) are not fully identified, we carried out a complete genome analysis to search for genes differentially expressed in ADHD and BP. Materials and methods: We recruited 39 patients (30 ADHD, 9 BP), aged 7 to 23 years. For evaluation of the psychiatric diagnosis, we used a semi-structured interview based on the K-SADS-PL (DSM-IV). RNA was extracted from peripheral blood and analyzed with the GeneChip (R) Human Genome U133-Plus 2.0 (Affymetrix). For the validation of differentially expressed genes, real-time PCR was used. Results: Hybridization and subsequent statistical analysis found 502 probe-sets with significant differences in expression in ADHD and BP patients. Of these, 82 had highly significant differences. Neuregulin (NRG1), cathepsins B and D (CTSB, CTSD) and prostaglandin-D2-synthase (FTGDS) were chosen for semi-quantitative mRNA determination. The expression of PTGDS was statistically increased in ADHD relative to BP patients (p = 0.01). We found no such differential expression with NRG1, CTSB and CTSD genes (p > 0.05). Conclusions: The gene coding for FTGDS was found to be more expressed in patients with ADHD relative to patients with BP, indicating a possible link with the differential etiology of ADHD. The experimental approach we have used is, at least in part, validated by the detection of proteins directly concerned with brain functions, and shows a possible way forward for studies of the connection between brain function genes and psychiatric disorders. Limitations: Confirmation of our findings requires a larger sample of patients with clearly-defined phenotypes. (C) 2012 Elsevier B.V. All rights reserved.

Targeting receptor tyrosine kinase (RTK) degradation may be an interesting approach to reduce RTK cell signaling in cancer cells. Here we show that increasing E3 ubiquitin ligase casitas B-lineage lymphoma (c-Cbl) expression using lentiviral infection decreased osteosarcoma cell replication and survival and reduced cell migration and invasion in murine and human osteosarcoma cells. Conversely, c-Cbl inhibition using short hairpin RNA (shRNA) increased osteosarcoma cell growth and survival, as well as invasion and migration, indicating that c-Cbl plays a critical role as a bone tumor suppressor. Importantly, the anticancer effect of increasing c-Cbl expression in osteosarcoma cells was related mainly to the downregulation of epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor alpha (PDGFRa). In a murine bone tumor model, increasing c-Cbl expression also reduced RTK expression, resulting in decreased tumor cell proliferation and survival and reduced tumor growth. Interestingly, increasing c-Cbl also markedly reduced lung metastasis in mice. Tissue microarray analysis revealed that low c-Cbl protein expression is associated with elevated EGFR and PDGFRa protein levels in human osteosarcoma with poor outcome. This study shows that increasing c-Cbl expression reduces osteosarcoma cell growth, survival, and metastasis in part through downregulation of RTKs, which supports the potential therapeutic interest of targeting c-Cbl in malignant bone diseases involving increased RTK.

Osteosarcoma is the most common primary tumor of bone. The rapid development of metastatic lesions and resistance to chemotherapy remain major mechanisms responsible for the failure of treatments and the poor survival rate for patients. We showed previously that the HMGCoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitor statin exhibits antitumoral effects on osteosarcoma cells. Here, using microarray analysis, we identify Cyr61 as a new target of statins. Transcriptome and molecular analyses revealed that statins downregulate Cyr61 expression in human and murine osteosarcoma cells. Cyr61 silencing in osteosarcoma cell lines enhanced cell death and reduced cell migration and cell invasion compared with parental cells, whereas Cyr61 overexpression had opposite effects. Cyr61 expression was evaluated in 231 tissue cores from osteosarcoma patients. Tissue microarray analysis revealed that Cyr61 protein expression was higher in human osteosarcoma than in normal bone tissue and was further increased in metastatic tissues. Finally, tumor behavior and metastasis occurrence were analyzed by intramuscular injection of modified osteosarcoma cells into BALB/c mice. Cyr61 overexpression enhanced lung metastasis development, whereas cyr61 silencing strongly reduced lung metastases in mice. The results reveal that cyr61 expression increases with tumor grade in human osteosarcoma and demonstrate that cyr61 silencing inhibits in vitro osteosarcoma cell invasion and migration as we

Our findings suggest that these polymorphisms may affect osteosarcoma treatment efficacy. If these associations are independently validated, these variants could be used as genetic predictors of clinical outcome in the treatment of osteosarcoma, helping in the design of individualized therapy.

This is the largest analysis of height at diagnosis and birth-weight in relation to osteosarcoma. It suggests that rapid bone growth during puberty and in utero contributes to OS etiology.

We report a new germline mutation in exon 13 of the hMSH2 gene (c.2081T>C; F694S) in a patient diagnosed with colorectal carcinoma. The patient's family fulfilled the clinical criteria of the Bethesda guidelines for Lynch syndrome. The segregation analysis determined the presence of the mutation in the proband's mother (breast cancer younger than 40 years old) and in two healthy daughters. The mutation was not present in 116 normal controls screened. The medical implications for the carrier relatives are discussed.