Nuestros investigadores

Jackeline Agorreta Arrazubi

Publicaciones científicas más recientes (desde 2010)

Autores: Ajona, Daniel; et al.
ISSN 1073-449X  Vol. 197  Nº 9  2018  págs. 1164 - 1176
RATIONALE: C5aR1 (CD88), a receptor for complement anaphylatoxin C5a, is a potent immune mediator. Its impact on malignant growth and dissemination of non-small cell lung cancer cells is poorly understood. OBJECTIVES: To investigate the contribution of the C5a/C5aR1 axis to the malignant phenotype of non-small cell lung cancer cells, particularly in skeletal colonization, a preferential lung metastasis site. METHODS: Association between C5aR1 expression and clinical outcome was assessed in silico and validated by immunohistochemistry. Functional significance was evaluated by lentiviral gene silencing and ligand l-aptamer inhibition in in vivo models of lung cancer bone metastasis. In vitro functional assays for signaling, migration, invasion, metalloprotease activity, and osteoclastogenesis were also performed. MEASUREMENTS AND MAIN RESULTS: High levels of C5aR1 in human lung tumors were significantly associated with shorter recurrence-free survival, overall survival, and bone metastasis. Silencing of C5aR1 in lung cancer cells led to a substantial reduction in skeletal metastatic burden and osteolysis in in vivo models. Furthermore, metalloproteolytic, migratory, and invasive tumor cell activities were modulated in vitro by C5aR1 stimulation or gene silencing. l-Aptamer blockade or C5aR1 silencing significantly reduced the osseous metastatic activity of lung cancer cells in vivo. This effect was associated with decreased osteoclastogenic activity in vitro and was rescued by the exogenous addition of the chemokine CXCL16. CONCLUSIONS: Disruption of C5aR1 signaling in lung cancer cells abrogates their tumor-associated osteoclastogenic activity, impairing osseous colonization. This study unveils the role played by the C5a/C5aR1 axis in lung cancer dissemination and supports its potential use as a novel therapeutic target.
Autores: Ajona, Daniel; Ortiz Espinosa, S.; Moreno, H. ; et al.
ISSN 2159-8274  Vol. 7  Nº 7  2017  págs. 694 - 703
Disruption of the programmed cell death protein 1 (PD-1) pathway with immune checkpoint inhibitors represents a major breakthrough in the treatment of non-small cell lung cancer. We hypothesized that combined inhibition of C5a/C5aR1 and PD-1 signaling may have a synergistic antitumor effect. The RMP1-14 antibody was used to block PD-1, and an L-aptamer was used to inhibit signaling of complement C5a with its receptors. Using syngeneic models of lung cancer, we demonstrate that the combination of C5a and PD-1 blockade markedly reduces tumor growth and metastasis and leads to prolonged survival. This effect is accompanied by a negative association between the frequency of CD8 T cells and myeloid-derived suppressor cells within tumors, which may result in a more complete reversal of CD8 T-cell exhaustion. Our study provides support for the clinical evaluation of anti-PD-1 and anti-C5a drugs as a novel combination therapeutic strategy for lung cancer. SIGNIFICANCE: Using a variety of preclinical models of lung cancer, we demonstrate that the blockade of C5a results in a substantial improvement in the efficacy of anti-PD-1 antibodies against lung cancer growth and metastasis. This study provides the preclinical rationale for the combined blockade of PD-1/PD-L1 and C5a to restore antitumor immune responses, inhibit tumor cell growth, and improve outcomes of patients with lung cancer. (C) 2017 AACR.
Autores: Agorreta, J; Garmendia, Irati; Pajares, María Josefa; et al.
ISSN 1556-0864  Vol. 12  Nº 1  2017  págs. S446 - S447
Autores: Azpilikueta, A.; Agorreta, J; Pérez, José Luis; et al.
ISSN 1556-0864  Vol. 11  Nº 4  2016  págs. 524 - 536
INTRODUCTION: Anti-programmed cell death 1 (anti-PD-1) and anti-programmed cell death ligand 1 (PD-L1) antagonist monoclonal antibodies (mAbs) against metastatic non-small cell lung cancer with special efficacy in patients with squamous cell lung cancer are being developed in the clinic. However, robust and reliable experimental models to test immunotherapeutic combinations in squamous lung tumors are still lacking. METHODS: We generated a transplantable squamous cell carcinoma cell line (UN-SCC680AJ) from a lung tumor induced by chronic N-nitroso-tris-chloroethylurea mutagenesis in A/J mice. Tumor cells expressed cytokeratins, overexpressed p40, and lacked thyroid transcription factor 1, confirming the squamous lineage reported by histological analysis. More than 200 mutations found in its exome suggested potential for antigenicity. Immunocompetent mice subcutaneously implanted with this syngeneic cell line were treated with anti-CD137 and/or anti-PD-1 mAbs and monitored for tumor growth/progression or assessed for intratumoral leukocyte infiltration using immunohistochemical analysis and flow cytometry. RESULTS: In syngeneic mice, large 12-day-established tumors derived from the transplantable cell line variant UN-SCC680AJ were amenable to curative treatment with anti-PD-1, anti-PD-L1, or anti-CD137 immunostimulatory mAbs. Single-agent therapies lost curative efficacy when treatment was started beyond day +17, whereas a combination of anti-PD-1 plus anti-CD137 achieved complete rejections. Tumor cells expressed weak baseline PD-L1 on the plasma membrane, but this could be readily induced by interferon-¿. Combined treatment efficacy required CD8 T cells and induced a leukocyte infiltrate in which T lymphocytes co-expressing CD137 and PD-1 were prominent. CONCLUSIONS: These promising results advocate the use of combined anti-PD-1/PD-L1 plus anti-CD137 mAb immunotherapy for the treatment of squamous non-small cell lung cancer in the clinical setting.
Autores: Aramburu, A.; Pajares, María Josefa; Agorreta, J; et al.
ISSN 1471-2164  Vol. 16  2015  págs. 752
Background: The development of a more refined prognostic methodology for early non-small cell lung cancer (NSCLC) is an unmet clinical need. An accurate prognostic tool might help to select patients at early stages for adjuvant therapies. Results: A new integrated bioinformatics searching strategy, that combines gene copy number alterations and expression, together with clinical parameters was applied to derive two prognostic genomic signatures. The proposed methodology combines data from patients with and without clinical data with a priori information on the ability of a gene to be a prognostic marker. Two initial candidate sets of 513 and 150 genes for lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC), respectively, were generated by identifying genes which have both: a) significant correlation between copy number and gene expression, and b) significant prognostic value at the gene expression level in external databases. From these candidates, two panels of 7 (ADC) and 5 (SCC) genes were further identified via semi-supervised learning. These panels, together with clinical data (stage, age and sex), were used to construct the ADC and SCC hazard scores combining clinical and genomic data. The signatures were validated in two independent datasets (n = 73 for ADC, n = 97 for SCC), confirming that the prognostic value of both clinical-genomic models is robust, statistically significant (P = 0.008 for ADC and P = 0.019 for SCC) and outperforms both the clinical models (P = 0.060 for ADC and P = 0.121 for SCC) and the genomic models applied separately (P = 0.350 for ADC and P = 0.269 for SCC). Conclusion: The present work provides a methodology to generate a robust signature using copy number data that can be potentially used to any cancer. Using it, we found new prognostic scores based on tumor DNA that, jointly with clinical information, are able to predict overall survival (OS) in patients with early-stage ADC and SCC.
Autores: Pio, R; Agorreta, J; Montuenga, Luis;
ISSN 0022-5223  Vol. 150  Nº 4  2015  págs. 986 - 992
Objective: The current staging system for lung cancer is not sufficient to accurately identify those patients with early-stage tumors who would benefit from postsurgery chemotherapy. The objective of this study was to validate a prognostic signature based on the expression of 5 RNA (ribonucleic acid) metabolism-related genes. Methods: Five lung cancer microarray datasets, 3 from adenocarcinomas and 2 from squamous cell carcinomas, were analyzed. Kaplan-Meier survival curves and Cox proportional hazards models were used to evaluate the relationship between the classifier and recurrence and survival. Results: Statistically significant differences in relapse-free survival and overall survival were observed when lung adenocarcinoma patients were divided into 3 risk groups. The prognostic information provided by the signature was independent from other demographic and disease variables, including stage. Significant differences in survival were observed between low-and high-risk groups in stage-IB patients: 5-year survival rates ranged from 83% to 100% in the low-risk groups, and from 30% to 71% in the high-risk groups, depending on the dataset. The RNA metabolism score additionally displayed an association with the benefit of adjuvant chemotherapy (P<. 001), suggesting that those patients in the low-risk group are not good candidates for this treatment. Conclusions: The RNA metabolism signature is a prognostic marker that may be useful for predicting survival and optimizing the benefit of adjuvant chemotherapy in patients with lung adenocarcinoma.
Autores: Grbesa, I.; Pajares, María Josefa; Agorreta, J; et al.
Revista: PLOS ONE
ISSN 1932-6203  Vol. 10  Nº 4  2015  págs. e0124670
Sirtuin 1 (SIRT1) and sirtuin 2 (SIRT2) are NAD+-dependent protein deacetylases involved in the regulation of key cancer-associated genes. In this study we evaluated the relevance of these deacetylases in lung cancer biology. Material and Methods Protein levels of SIRT1 and SIRT2 were determined in non-small cell lung cancer (NSCLC) cell lines and primary tumors from 105 patients. Changes in proliferation were assessed after SIRT1 and SIRT2 downregulation in lung cancer cell lines using siRNA-mediated technology or tenovin-1, a SIRT1 and SIRT2 inhibitor. Results High SIRT1 and SIRT2 protein levels were found in NSCLC cell lines compared with nontumor lung epithelial cells. The expression of SIRT1 and SIRT2 proteins was also significantly higher in lung primary tumors than in normal tissue (P<0.001 for both sirtuins). Stronger nuclear SIRT1 staining was observed in adenocarcinomas than in squamous cell carcinomas (P=0.033). Interestingly, in NSCLC patients, high SIRT1 and SIRT2 expression levels were associated with shorter recurrence-free survival (P=0.04 and P=0.007, respectively). Moreover, the combination of high SIRT1 and SIRT2 expression was an independent prognostic factor for shorter recurrence-free survival (P=0.002) and overall survival (P=0.022). In vitro studies showed that SIRT1 and/or SIRT2 downregulation significantly decreased proliferation of NSCLC. Conclusions Our results support the hypothesis that SIRT1 and SIRT2 have a protumorigenic role in lu
Autores: Pajares, María Josefa; Agorreta, J; Behrens, C.; et al.
ISSN 0007-0920  Vol. 110  Nº 6  2014  págs. 1545 - 1551
Background: Transforming growth factor beta-induced protein (TGFBI) is a secreted protein that mediates cell anchoring to the extracellular matrix. This protein is downregulated in lung cancer, and when overexpressed, contributes to apoptotic cell death. Using a small series of stage IV non-small cell lung cancer (NSCLC) patients, we previously suggested the usefulness of TGFBI as a prognostic and predictive factor in chemotherapy-treated late-stage NSCLC. In order to validate and extend these results, we broaden the analysis and studied TGFBI expression in a large series of samples obtained from stage I-IV NSCLC patients. Methods: TGFBI expression was assessed by immunohistochemistry in 364 completely resected primary NSCLC samples: 242 adenocarcinomas (ADCs) and 122 squamous cell carcinomas (SCCs). Kaplan-Meier curves, log-rank tests and the Cox proportional hazards model were used to analyse the association between TGFBI expression and survival. Results: High TGFBI levels were associated with longer overall survival (OS, P < 0.001) and progression-free survival (PFS, P < 0.001) in SCC patients who received adjuvant platinium-based chemotherapy. Moreover, multivariate analysis demonstrated that high TGFBI expression is an independent predictor of better survival in patients (OS: P = 0.030 and PFS: P = 0.026). Conclusions: TGFBI may be useful for the identification of a subset of NSCLC who may benefit from adjuvant therapy.
Autores:  et al.
ISSN 1574-7891  Vol. 8  Nº 2  2014  págs. 196 - 206
Lung adenocarcinoma (ADC) is the most common lung cancer subtype and presents a high mortality rate. Clinical recurrence is often associated with the emergence of metastasis and treatment resistance. The purpose of this study was to identify genes with high prometastatic activity which could potentially account for treatment resistance. Global transcriptomic profiling was performed by robust microarray analysis in highly metastatic subpopulations. Extensive in vitro and in vivo functional studies were achieved by overexpression and by silencing gene expression. We identified the small GTPase RHOB as a gene that promotes early and late stages of metastasis in ADC. Gene silencing of RHOB prevented metastatic activity in a systemic murine model of bone metastasis. These effects were highly dependent on tumor-host interactions. Clinical analysis revealed a marked association between high RHOB levels and poor survival. Consistently, high RHOB levels promote metastasis progression, taxane-chemoresistance, and contribute to the survival advantage to ¿-irradiation. We postulate that RHOB belongs to a novel class of "genes of recurrence" that have a dual role in metastasis and treatment resistance.
Autores: Agorreta, J; Hu, J.; Liu, D.; et al.
ISSN 1541-7786  Vol. 12  Nº 5  2014  págs. 660 - 669
The TNF receptor-associated protein 1 (TRAP1) is a mitochondrial HSP that has been related to drug resistance and protection from apoptosis in colorectal and prostate cancer. Here, the effect of TRAP1 ablation on cell proliferation, survival, apoptosis, and mitochondrial function was determined in non-small cell lung cancer (NSCLC). In addition, the prognostic value of TRAP1 was evaluated in patients with NSCLC. These results demonstrate that TRAP1 knockdown reduces cell growth and clonogenic cell survival. Moreover, TRAP1 downregulation impairs mitochondrial functions such as ATP production and mitochondrial membrane potential as measured by TMRM (tetramethylrhodamine methylester) uptake, but it does not affect mitochondrial density or mitochondrial morphology. The effect of TRAP1 silencing on apoptosis, analyzed by flow cytometry and immunoblot expression (cleaved PARP, caspase-9, and caspase-3) was cell line and context dependent. Finally, the prognostic potential of TRAP1 expression in NSCLC was ascertained via immunohistochemical analysis which revealed that high TRAP1 expression was associated with increased risk of disease recurrence (univariate analysis, P = 0.008; multivariate analysis, HR: 2.554; 95% confidence interval, 1.085-6.012; P = 0.03). In conclusion, these results demonstrate that TRAP1 impacts the viability of NSCLC cells, and that its expression is prognostic in NSCLC.
Autores: Agorreta, J; Hu, J.; Pezzella, F.;
ISSN 2331-4737  Vol. 1  Nº 9  2014  págs. 560 - 561
Autores: Larráyoz, Marta; Pio, R; Pajares, María Josefa; et al.
ISSN 1757-4684  Vol. 6  Nº 4  2014  págs. 539 - 550
The vascular endothelial growth factor (VEGF) pathway is a clinically validated antiangiogenic target for non-small cell lung cancer (NSCLC). However, some contradictory results have been reported on the biological effects of antiangiogenic drugs. In order to evaluate the efficacy of these drugs in NSCLC histological subtypes, we analyzed the anticancer effect of two anti-VEGFR2 therapies (sunitinib and DC101) in chemically induced mouse models and tumorgrafts of lung adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Antiangiogenic treatments induced vascular trimming in both histological subtypes. In ADC tumors, vascular trimming was accompanied by tumor stabilization. In contrast, in SCC tumors, antiangiogenic therapy was associated with disease progression and induction of tumor proliferation. Moreover, in SCC, anti-VEGFR2 therapies increased the expression of stem cell markers such as aldehyde dehydrogenase 1A1, CD133, and CD15, independently of intratumoral hypoxia. In vitro studies with ADC cell lines revealed that antiangiogenic treatments reduced pAKT and pERK signaling and inhibited proliferation, while in SCC-derived cell lines the same treatments increased pAKT and pERK, and induced survival. In conclusion, this study evaluates for the first time the effect of antiangiogenic drugs in lung SCC murine models in vivo and sheds light on the contradictory results of antiangiogenic therapies in NSCLC.
Autores: Ajona, Daniel; Pajares, María Josefa; et al.
ISSN 1460-2105  Vol. 105  Nº 18  2013  págs. 1385 - 1393
BACKGROUND: There is a medical need for diagnostic biomarkers in lung cancer. We evaluated the diagnostic performance of complement activation fragments. METHODS: We assessed complement activation in four bronchial epithelial and seven lung cancer cell lines. C4d, a degradation product of complement activation, was determined in 90 primary lung tumors; bronchoalveolar lavage supernatants from patients with lung cancer (n = 50) and nonmalignant respiratory diseases (n = 22); and plasma samples from advanced (n = 50) and early lung cancer patients (n = 84) subjects with inflammatory lung diseases (n = 133), and asymptomatic individuals enrolled in a lung cancer computed tomography screening program (n = 190). Two-sided P values were calculated by Mann-Whitney U test. RESULTS: Lung cancer cells activated the classical complement pathway mediated by C1q binding that was inhibited by phosphomonoesters. Survival was decreased in patients with high C4d deposition in tumors (hazard ratio [HR] = 3.06; 95% confidence interval [CI] = 1.18 to 7.91). C4d levels were increased in bronchoalveolar lavage fluid from lung cancer patients compared with patients with nonmalignant respiratory diseases (0.61 ± 0.87 vs 0.16 ± 0.11 µg/mL; P < .001). C4d levels in plasma samples from lung cancer patients at both advanced and early stages were also increased compared with control subjects (4.13 ± 2.02 vs 1.86 ± 0.95 µg/mL, P < 0.001; 3.18 ± 3.20 vs 1.13 ± 0.69 µg/mL, P < .001, respectively). C4d plasma levels were associated with shorter survival in patients at advanced (HR = 1.59; 95% CI = 0.97 to 2.60) and early stages (HR = 5.57; 95% CI = 1.60 to 19.39). Plasma C4d levels were reduced after surgical removal of lung tumors (P < .001) and were associated with increased lung cancer risk in asymptomatic individuals with (n = 32) or without lung cancer (n = 158) (odds ratio = 4.38; 95% CI = 1.61 to 11.93). CONCLUSIONS: Complement fragment C4d may serve as a biomarker for early diagnosis and prognosis of lung cancer.
Autores: Garasa, S.; Pajares, María Josefa; et al.
ISSN 0020-7136  Vol. 132  Nº 9  2013  págs. 1986 - 1995
Collapsin response mediator protein-2 (CRMP-2) is the first described and most studied member of a family of proteins that mediate the addition of tubulin dimers to the growing microtubule. CRMPs have mainly been studied in the nervous system, but recently, they have been described in other tissues where they participate in vesicle transport, migration and mitosis. In this work, we aimed at studying the role of CRMP-2 in lung cancer cell division. We first explored the expression of CRMP-2 and phosphorylated (Thr 514) CRMP-2 in 91 samples obtained from patients with localized nonsmall cell lung cancer. We observed a significant correlation between high levels of nuclear phosphorylated CRMP-2 and poor prognosis in those patients. Interestingly, this association was only positive for untreated patients. To provide a mechanistic explanation to these findings, we used in vitro models to analyze the role of CRMP-2 and its phosphorylated forms in cell division. Thus, we observed by confocal microscopy and immunoprecipitation assays that CRMP-2 differentially colocalizes with the mitotic spindle during cell division. The use of phosphodefective or phosphomimetic mutants of CRMP-2 allowed us to prove that anomalies in the phosphorylation status of CRMP-2 result in changes in the mitotic tempo, and increments in the number of multinucleated cells. Finally, here we demonstrate that CRMP-2 phosphorylation impairment, or silencing induces p53 expression and promotes apoptosis through caspase 3 activation. These results pointed to CRMP-2 phosphorylation as a prognostic marker and potential new target to be explored in cancer therapy.
Autores: Bastarrika, Gorka; Agorreta, J; et al.
ISSN 1361-8423  Vol. 17  Nº 8  2013  págs. 1095-1105
We present and evaluate an automatic and quantitative method for the complex task of characterizing individual nodule volumetric progression in a longitudinal mouse model of lung cancer. Fourteen A/J mice received an intraperitoneal injection of urethane. Respiratory-gated micro-CT images of the lungs were acquired at 8, 22, and 37 weeks after injection. A radiologist identified a total of 196, 585 and 636 nodules, respectively. The three micro-CT image volumes from every animal were then registered and the nodules automatically matched with an average accuracy of 99.5%. All nodules detected at week 8 were tracked all the way to week 37, and volumetrically segmented to measure their growth and doubling rates. 92.5% of all nodules were correctly segmented, ranging from the earliest stage to advanced stage, where nodule segmentation becomes more challenging due to complex anatomy and nodule overlap. Volume segmentation was validated using a foam lung phantom with embedded polyethylene microspheres. We also correlated growth rates with nodule phenotypes based on histology, to conclude that the growth rate of malignant tumors is significantly higher than that of benign lesions. In conclusion, we present a turnkey solution that combines longitudinal imaging with nodule matching and volumetric nodule segmentation resulting in a powerful tool for preclinical research.
Autores: Freire, Francisco Javier; Ajona, Daniel; et al.
ISSN 1522-8002  Vol. 15  Nº 8  2013  págs. 913 - 924
The association between inflammation and lung tumor development has been clearly demonstrated. However, little is known concerning the molecular events preceding the development of lung cancer. In this study, we characterize a chemically induced lung cancer mouse model in which lung cancer developed in the presence of silicotic chronic inflammation. Silica-induced lung inflammation increased the incidence and multiplicity of lung cancer in mice treated with N-nitrosodimethylamine, a carcinogen found in tobacco smoke. Histologic and molecular analysis revealed that concomitant chronic inflammation contributed to lung tumorigenesis through induction of preneoplastic changes in lung epithelial cells. In addition, silica-mediated inflammation generated an immunosuppressive microenvironment in which we observed increased expression of programmed cell death protein 1 (PD-1), transforming growth factor-beta 1, monocyte chemotactic protein 1 (MCP-1), lymphocyte-activation gene 3 (LAG3), and forkhead box P3 (FOXP3), as well as the presence of regulatory T cells. Finally, the K-RAS mutational profile of the tumors changed from Q61R to G12D mutations in the inflammatory milieu. In summary, we describe some of the early molecular changes associated to lung carcinogenesis in a chronic inflammatory microenvironment and provide novel information concerning the mechanisms underlying the formation and the fate of preneoplastic lesions in the silicotic lung.
Autores: Pajares, María Josefa; Agorreta, J; Larráyoz, Marta; et al.
Revista: Journal of Clinical Oncology
ISSN 0732-183X  Vol. 30  Nº 10  2012  págs. 1129 - 1136
Purpose: Antiangiogenic therapies targeting the vascular endothelial growth factor (VEGF) pathway have yielded more modest clinical benefit to patients with non-small-cell lung cancer (NSCLC) than initially expected. Clinical data suggest a distinct biologic role of the VEGF pathway in the different histologic subtypes of lung cancer. To clarify the influence of histologic differentiation in the prognostic relevance of VEGF-mediated signaling in NSCLC, we performed a concomitant analysis of the expression of three key elements of the VEGF pathway in the earliest stages of the following two principal histologic subtypes: squamous cell carcinoma (SCC) and adenocarcinoma (ADC). Patients and Methods: We evaluated tumor cell expression of VEGF, VEGF receptor (VEGFR) 1, and VEGFR2 using automatic immunostaining in a series of 298 patients with early-stage NSCLC recruited as part of the multicenter European Early Lung Cancer Detection Group project. A score measuring the VEGF signaling pathway was calculated by adding the tumor cell expression value of VEGF and its two receptors. The results were validated in two additional independent cohorts of patients with NSCLC. Results: The combination of high VEGF, VEGFR1, and VEGFR2 protein expression was associated with lower risk of disease progression in early SCC (univariate analysis, P = .008; multivariate analysis, hazard ratio, 0.62; 95% CI, 0.42 to 0.92; P = .02). The results were validated in two independent patient cohorts, confirming the favorable prognostic value of high VEGF signaling score in early lung SCC. Conclusion: Our results clearly indicate that the combination of high expression of the three key elements in the VEGF pathway is associated with a good prognosis in patients with early SCC but not in patients with ADC.
Autores: Ormazábal, Cristina; et al.
ISSN 1078-0432  Vol. 18  Nº 4  2012  págs. 969 - 980
Purpose: We investigated the role of the collagen-binding receptor discoidin domain receptor-1 (DDR1) in the initiation and development of bone metastasis. Experimental Design: We conducted immunohistochemical analyses in a cohort of 83 lung cancer specimens and examined phosphorylation status in a panel of human lung cancer cell lines. Adhesion, chemotaxis, invasiveness, metalloproteolytic, osteoclastogenic, and apoptotic assays were conducted in DDR1-silenced cells. In vivo, metastatic osseous homing and colonization were assessed in a murine model of metastasis. Results: DDR1 was expressed in a panel of human lung cancer cell lines, and high DDR1 levels in human lung tumors were associated with poor survival. Knockdown (shDDR1) cells displayed unaltered growth kinetics in vitro and in vivo. In contrast, shDDR1 cells showed reduced invasiveness in collagen matrices and increased apoptosis in basal conditions and induced apoptosis in vitro. More importantly, conditioned media of DDR1-knockdown cells decreased osteoclastogenic activity in vitro. Consequently, in a model of tumor metastasis to bone, lack of DDR1 showed decreased metastatic activity associated with reduced tumor burden and osteolytic lesions. These effects were consistent with a substantial reduction in the number of cells reaching the bone compartment. Moreover, intratibial injection of shDDR1 cells significantly decreased bone tumor burden, suggesting impaired colonization ability that was highly dependent on the bone microenvironment. Conclusions: Disruption of DDR1 hampers tumor cell survival, leading to impaired early tumor-bone engagement during skeletal homing. Furthermore, inhibition of DDR1 crucially alters bone colonization. We suggest that DDR1 represents a novel therapeutic target involved in bone metastasis.
Autores:  et al.
ISSN 1073-449X  Vol. 186  Nº 1  2012  págs. 96 - 105
Rationale: Efficient metastasis requires survival and adaptation of tumor cells to stringent conditions imposed by the extracellular milieu. Identification of critical survival signaling pathways in tumor cells might unveil novel targets relevant in disease progression. Objectives: To investigate the contribution of activated protein C (APC) and its receptor (endothelial protein C receptor [EPCR]) in animal models of lung cancer metastasis and in patients with lung adenocarcinoma. Methods: Signaling pathway triggered by APC/EPCR and its relevance in apoptosis was studied in vitro. Functional significance was assessed by silencing and blocking antibodies in several in vivo models of lung cancer metastasis in athymic nude Foxn1(nu) mice. We examined EPCR levels using a microarray dataset of 107 patients. Immunohistochemical analysis was performed in an independent cohort of 295 patients with lung adenocarcinoma. Measurements and Main Results: The effects of APC binding to EPCR rapidly triggered Akt and extracellular signal-regulated kinase signaling pathways, leading to attenuated in vitro apoptosis. In vivo, silencing of EPCR expression or blocking APC/EPCR interaction reduced infiltration in the target organ, resulting in impaired prometastatic activity. Moreover, overexpression of EPCR induced an increased metastatic activity to target organs. Analysis of clinical samples showed a robust association between high EPCR levels and poor prognosis, particularly in stage I patients. Conclusions: EPCR and its ligand APC promote cell survival that contributes to tumor cell endurance to stress favoring prometastatic activity of lung adenocarcinoma. EPCR/APC is a novel target of relevance in the clinical outcome of early-stage lung cancer.
Autores: Ponz-Sarvise, Mariano; Nguewa, Paul; Pajares, María Josefa; et al.
ISSN 1078-0432  Vol. 17  Nº 12  2011  págs. 4155 -4166
Autores: Pio, R; Pajares, María Josefa; Aibar, E; et al.
Revista: B M C Genomics-(BioMed Central Ltd.)
ISSN 1471-2164  Vol. 3  Nº 11  2010  págs. 352 - 352
Autores: Liu, D; Hu, J; Agorreta, J; et al.
Revista: Cancer Letters
ISSN 0304-3835  Vol. 296  Nº 2  2010  págs. 194 - 205
Tumor necrosis factor (TNF) receptor-associated protein 1(TRAP1/HSP75) is a heat shock protein, highly homologous to HSP90, which acts as a molecular chaperone to retinoblastoma protein (Rb) during cellular stress although the current literature suggests that this protein could have additional functions. The aim of this study was to identify the pathways regulated by TRAP1. TRAP1 was silenced by siRNA in A549 cells and re-expressed by stable transfection in MDA231 cells. After growing the cells for 16h under normoxic or hypoxic conditions, oligonucleotide microarrays were employed to detect differentially expressed genes. In TRAP1 positive cells there are high levels of cell proliferation promoting genes coding for G protein coupled receptors, cell adhesion genes and genes associated with Rho-kinase pathways. In TRAP1 negative cells there are higher levels of genes involved in cell motility and metastatic spread. Pathway map analysis shows that TRAP1 controls cell cycle activity through the tumor necrosis factor pathways. Our data suggest that in many tumors TRAP1 could activate proliferation whilst inhibiting metastatic spread.
Autores: Larzabal, L; Larráyoz, Marta; Molina, Enrique; et al.
ISSN 1476-4598  Vol. 9  Nº 320  2010  págs. 1 - 14
BACKGROUND: Different isoforms of VEGF-A (mainly VEGF¿¿¿, VEGF¿¿¿ and VEGF189) have been shown to display particular angiogenic properties in the generation of a functional tumor vasculature. Recently, a novel class of VEGF-A isoforms, designated as VEGF(xxx)b, generated through alternative splicing, have been described. Previous studies have suggested that these isoforms may inhibit angiogenesis. In the present work we have produced recombinant VEGF¿¿¿/¿¿¿b proteins in the yeast Pichia pastoris and constructed vectors to overexpress these isoforms and assess their angiogenic potential. RESULTS: Recombinant VEGF¿¿¿/¿¿¿b proteins generated either in yeasts or mammalian cells activated VEGFR2 and its downstream effector ERK1/2, although to a lesser extent than VEGF¿¿¿. Furthermore, treatment of endothelial cells with VEGF¿¿¿/¿¿¿b increased cell proliferation compared to untreated cells, although such stimulation was lower than that induced by VEGF¿¿¿. Moreover, in vivo angiogenesis assays confirmed angiogenesis stimulation by VEGF¿¿¿/¿¿¿b isoforms. A549 and PC-3 cells overexpressing VEGF¿¿¿b or VEGF¿¿¿b (or carrying the PCDNA3.1 empty vector, as control) and xenotransplanted into nude mice showed increased tumor volume and angiogenesis compared to controls. To assess whether the VEGF(xxx)b isoforms are differentially expressed in tumors compared to healthy tissues, immunohistochemical analysis was conducted on a breast cancer tissue microarray. A significant increase (p < 0.05) in both VEGF(xxx)b and total VEGF-A protein expression in infiltrating ductal carcinomas compared to normal breasts was observed. A positive significant correlation (r = 0.404, p = 0.033) between VEGF(xxx)b and total VEGF-A was found. CONCLUSIONS: Our results demonstrate that VEGF¿¿¿/¿¿¿b are not anti-angiogenic, but weakly angiogenic isoforms of VEGF-A. In addi
Autores: Pio, R, (Autor de correspondencia); Pajares, María Josefa; Aibar, E.; et al.
ISSN 1471-2164  Vol. 11  2010  págs. 352
Background: Microarrays strategies, which allow for the characterization of thousands of alternative splice forms in a single test, can be applied to identify differential alternative splicing events. In this study, a novel splice array approach was developed, including the design of a high-density oligonucleotide array, a labeling procedure, and an algorithm to identify splice events. Results: The array consisted of exon probes and thermodynamically balanced junction probes. Suboptimal probes were tagged and considered in the final analysis. An unbiased labeling protocol was developed using random primers. The algorithm used to distinguish changes in expression from changes in splicing was calibrated using internal non-spliced control sequences. The performance of this splice array was validated with artificial constructs for CDC6, VEGF, and PCBP4 isoforms. The platform was then applied to the analysis of differential splice forms in lung cancer samples compared to matched normal lung tissue. Overexpression of splice isoforms was identified for genes encoding CEACAM1, FHL-1, MLPH, and SUSD2. None of these splicing isoforms had been previously associated with lung cancer. Conclusions: This methodology enables the detection of alternative splicing events in complex biological samples, providing a powerful tool to identify novel diagnostic and prognostic biomarkers for cancer and other pathologies.
Autores: Pajares, María Josefa; Agorreta, J; et al.
Revista: Molecular Cancer
ISSN 1476-4598  Vol. 28  Nº 9  2010  págs. 130
Autores: Ezponda, Teresa; Pajares, María Josefa; Agorreta, J; et al.
Revista: Clinical cancer research
ISSN 1078-0432  Vol. 16  Nº 16  2010  págs. 4113 - 4125
PURPOSE: SF2/ASF is a splicing factor recently described as an oncoprotein. In the present work, we examined the role of SF2/ASF in human non-small cell lung cancer (NSCLC) and analyzed the molecular mechanisms involved in SF2/ASF-related carcinogenesis. EXPERIMENTAL DESIGN: SF2/ASF protein levels were analyzed in 81 NSCLC patients by immunohistochemistry. SF2/ASF downregulation cellular models were generated using small interfering RNAs, and the effects on proliferation and apoptosis were evaluated. Survivin and SF2/ASF expression in lung tumors was analyzed by Western blot and immunohistochemistry. Survival curves and log-rank test were used to identify the association between the expression of the proteins and time to progression. RESULTS: Overexpression of SF2/ASF was found in most human primary NSCLC tumors. In vitro downregulation of SF2/ASF induced apoptosis in NSCLC cell lines. This effect was associated with a reduction in the expression of survivin, an antiapoptotic protein widely upregulated in cancer. In fact, SF2/ASF specifically bound survivin mRNA and enhanced its translation, via a mammalian target of rapamycin complex 1 (mTORC1) pathway-dependent mechanism, through the phosphorylation and inactivation of the translational repressor 4E-BP1. Moreover, SF2/ASF promoted the stability of survivin mRNA. A strong correlation was observed between the expression of SF2/ASF and survivin in tumor biopsies from NSCLC patients, supporting the concept that survivin expression levels are controlled by SF2/ASF. Furthermore, combined expression of these proteins was associated with prognosis. CONCLUSION: This study provides novel data on the mTORC1- and survivin-dependent mechanisms of SF2/ASF-related carcinogenic
Autores: Montuenga, Luis; Agorreta, J;
Libro:  Técnicas en histología y biología celular
2014  págs. 127 - 154



Técnicas moleculares in situ. 
Universidad de Navarra - Facultad de Medicina.

Métodos histológicos (F. Ciencias). 
Universidad de Navarra - Facultad de Medicina.

Métodos instrumentales en bioquímica y biología molecular II (F.Ciencias). 
Universidad de Navarra - Facultad de Ciencias.