Nuestros investigadores

Diego Oscar Alignani 

Publicaciones científicas más recientes (desde 2010)

Autores: Ochoa, María del Carmen; Perez-Ruiz, E.; Minute, L. ; et al.
Revista: ONCOIMMUNOLOGY
ISSN 2162-402X  Vol. 8  Nº 7  2019  págs. 1599636
Daratumumab is an anti-CD38 fully human IgG1 mAb approved for multiple myeloma treatment. One of the proposed mechanisms of action is the induction of antibody-dependent cellular cytotoxicity (ADCC) mediated by NK cells. NK cells acquire surface CD137 expression in the presence of solid-phase-attached daratumumab and when encountering a daratumumab-coated CD38(+) tumor cell line. In this setting, addition of the agonist anti-CD137 mAb urelumab enhances NK-cell activation increasing CD25 expression and IFN gamma production. However, in vitro ADCC is not increased by the addition of urelumab both in 4h or 24h lasting experiments. To study urelumab-increased daratumumab-mediated ADCC activity in vivo, we set up a mouse model based on the intravenous administration of a luciferase-transfected multiple myeloma cell line of human origin, human NK cells and daratumumab to immuno-deficient NSG mice. In this model, intravenous administration of urelumab 24h after daratumumab delayed tumor growth and prolonged mice survival.
Autores: Moreno, Laura; Zabaleta, Aintzane; et al.
Revista: CLINICAL CANCER RESEARCH
ISSN 1078-0432  Vol. 25  Nº 10  2019  págs. 3176 - 3187
Purpose: Knowledge about the mechanism of action (MoA) of monoclonal antibodies (mAb) is required to understand which patients with multiple myeloma (MM) benefit the most from a given mAb, alone or in combination therapy. Although there is considerable research about daratumumab, knowledge about other anti-CD38 mAbs remains scarce. Experimental Design: We performed a comprehensive analysis of the MoA of isatuximab. Results: Isatuximab induces internalization of CD38 but not its significant release from MMcell surface. In addition, we uncovered an association between levels of CD38 expression and different MoA: (i) Isatuximab was unable to induce direct apoptosis on MM cells with CD38 levels closer to those in patients with MM, (ii) isatuximab sensitized CD38(hi) MMcells to bortezomib plus dexamethasone in the presence of stroma, (iii) antibody-dependent cellular cytotoxicity (ADCC) was triggered by CD38(lo) and CD38(hi) tumor plasma cells (PC), (iv) antibody-dependent cellular phagocytosis (ADCP) was triggered only by CD38(hi) MM cells, whereas (v) complement-dependent cytotoxicity could be triggered in less than half of the patient samples (those with elevated levels of CD38). Furthermore, we showed that isatuximab depletes CD38(hi) B-lymphocyte precursors and natural killer (NK) lymphocytes ex vivo-the latter through activation followed by exhaustion and eventually phagocytosis. Conclusions: This study provides a framework to understand response determinants in patients treated with isatuximab based on the number of MoA triggered by CD38 levels of expression, and for the design of effective combinations aimed at capitalizing disrupted tumor-stroma cell protection, augmenting NK lymphocyte-mediated ADCC, or facilitating ADCP in CD38(lo) MM patients.
Autores: Urtasun, R.; Elizalde, M.; et al.
Revista: NUCLEIC ACIDS RESEARCH
ISSN 0305-1048  Vol. 47  Nº 7  2019  págs. 3450 - 3466
Genome instability is related to disease development and carcinogenesis. DNA lesions are caused by genotoxic compounds but also by the dysregulation of fundamental processes like transcription, DNA replication and mitosis. Recent evidence indicates that impaired expression of RNA-binding proteins results in mitotic aberrations and the formation of transcription-associated RNA-DNA hybrids (R-loops), events strongly associated with DNA injury. We identify the splicing regulator SLU7 as a key mediator of genome stability. SLU7 knockdown results in R-loops formation, DNA damage, cell-cycle arrest and severe mitotic derangements with loss of sister chromatid cohesion (SCC). We define a molecular pathway through which SLU7 keeps in check the generation of truncated forms of the splicing factor SRSF3 (SRp20) (SRSF3-TR). Behaving as dominant negative, or by gain-of-function, SRSF3-TR impair the correct splicing and expression of the splicing regulator SRSF1 (ASF/SF2) and the crucial SCC protein sororin. This unique function of SLU7 was found in cancer cells of different tissue origin and also in the normal mouse liver, demonstrating a conserved and fundamental role of SLU7 in the preservation of genome integrity. Therefore, the dowregulation of SLU7 and the alterations of this pathway that we observe in the cirrhotic liver could be involved in the process of hepatocarcinogenesis.
Autores: Pascual, M.; Mena-Varas, M. ; Robles, Eloy Francisco; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 133  Nº 22  2019  págs. 2401 - 2412
Refractory or relapsed diffuse large B-cell lymphoma (DLBCL) often associates with the activated B-cell-like (ABC) subtype and genetic alterations that drive constitutive NF-kappa B activation and impair B-cell terminal differentiation. Here, we show that DNA damage response by p53 is a central mechanism suppressing the pathogenic cooperation of IKK2ca-enforced canonical NF-kappa B and impaired differentiation resulting from Blimp1 loss in ABC-DLBCL lymphomagenesis. We provide evidences that the interplay between these genetic alterations and the tumor microenvironment select for additional molecular addictions that promote lymphoma progression, including aberrant coexpression of FOXP1 and the B-cell mutagenic enzyme activation-induced deaminase, and immune evasion through major histocompatibility complex class II downregulation, PD-L1 upregulation, and T-cell exhaustion. Consistently, PD-1 blockade cooperated with anti-CD20-mediated B-cell cytotoxicity, promoting extended T-cell reactivation and antitumor specificity that improved long-term overall survival in mice. Our data support a pathogenic cooperation among NF-kappa B-driven prosurvival, genetic instability, and immune evasion mechanisms in DLBCL and provide preclinical proof of concept for including PD-1/PD-L1 blockade in combinatorial immunotherapy for ABC-DLBCL.
Autores: Ruiz, C. P.; Zabaleta, Aintzane; Puig, N.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 132  Nº Supl. 1  2018 
Autores: Goicoechea, Ibai; Puig, N. ; Cedena, M. T. ; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 132  Nº Supl. 1  2018  págs. 112
Autores: Cuenca, I.; Sanchez-Vega, B. ; Lourenco, Bruno David; et al.
Revista: HAEMATOLOGICA
ISSN 0390-6078  Vol. 103  Nº Supl. 2  2018  págs. 91 - 91
Autores: Vicari, M. ; Lara-Astiaso, D.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 132  Nº Supl. 1  2018  págs. 188
Autores: Lourenco, Bruno David; Puig, N.; Cedena, M. T.; et al.
Revista: LEUKEMIA
ISSN 0887-6924  Vol. 31  Nº 2  2017  págs. 382 - 392
The notion that plasma cells (PCs) are terminally differentiated has prevented intensive research in multiple myeloma (MM) about their phenotypic plasticity and differentiation. Here, we demonstrated in healthy individuals (n = 20) that the CD19 - CD81 expression axis identifies three bone marrow (BM) PC subsets with distinct age- prevalence, proliferation, replication- history, immunoglobulin- production, and phenotype, consistent with progressively increased differentiation from CD19+ CD81+ into CD19 - CD81+ and CD19 - CD81 - BMPCs. Afterwards, we demonstrated in 225 newly diagnosed MM patients that, comparing to normal BMPC counterparts, 59% had fully differentiated (CD19 - CD81 -) clones, 38% intermediate- differentiated (CD19 - CD81+) and 3% less- differentiated (CD19+ CD81+) clones. The latter patients had dismal outcome, and PC differentiation emerged as an independent prognostic marker for progression- free (HR: 1.7; P = 0.005) and overall survival (HR: 2.1; P = 0.006). Longitudinal comparison of diagnostic vs minimal- residual- disease samples (n = 40) unraveled that in 20% of patients, less- differentiated PCs subclones become enriched after therapy- induced pressure. We also revealed that CD81 expression is epigenetically regulated, that less- differentiated clonal PCs retain high expression of genes related to preceding B- cell stages (for example: PAX5), and show distinct mutation profile vs fully differentiated PC clones within individual patients. Together, we shed new light into PC plasticity and demonstrated that MM patients harbouring less- differentiated PCs have dismal survival, which might be related to higher chemoresistant potential plus different molecular and genomic profiles.
Autores: Mishima, Y.; Lourenco, Bruno David; Shi, J. T.; et al.
Revista: CELL REPORTS
ISSN 2211-1247  Vol. 19  Nº 1  2017  págs. 218 - 224
The development of sensitive and non-invasive "liquid biopsies'' presents new opportunities for longitudinal monitoring of tumor dissemination and clonal evolution. The number of circulating tumor cells (CTCs) is prognostic in multiple myeloma (MM), but there is little information on their genetic features. Here, we have analyzed the genomic landscape of CTCs from 29 MM patients, including eight cases with matched/paired bone marrow (BM) tumor cells. Our results show that 100% of clonal mutations in patient BM were detected in CTCs and that 99% of clonal mutations in CTCs were present in BM MM. These include typical driver mutations in MM such as in KRAS, NRAS, or BRAF. These data suggest that BM and CTC samples have similar clonal structures, as discordances between the two were restricted to subclonal mutations. Accordingly, our results pave the way for potentially less invasive mutation screening of MM patients through characterization of CTCs.
Autores: Fernandez-Poma, S. M.; Salas, Diego; et al.
Revista: CANCER RESEARCH
ISSN 0008-5472  Vol. 77  Nº 13  2017  págs. 3672 - 3684
Recent studies have found that tumor-infiltrating lymphocytes (TIL) expressing PD-1 can recognize autologous tumor cells, suggesting that cells derived from PD-1(+) TILs can be used in adoptive T-cell therapy (ACT). However, no study thus far has evaluated the antitumor activity of PD-1-selected TILs in vivo. In two mouse models of solid tumors, we show that PD-1 allows identification and isolationof tumor-specific TILs without previous knowledge of their antigen specificities. Importantly, despite the high proportion of tumor-reactive T cells present in bulk CD8 TILs before expansion, only T-cell products derived fromsorted PD-1(+), but not from PD-1(-) or bulk CD8 TILs, specifically recognized tumor cells. The fold expansion of PD-1(+) CD8 TILs was 10 times lower than that of PD-1(-) cells, suggesting that outgrowth of PD-1(-) cells was the limiting factor in the tumor specificity of cells derived from bulk CD8 TILs. The highly differentiated state of PD-1(+) cells was likely the main cause hampering ex vivo expansion of this subset. Moreover, PD-1 precisely identified marrow-infiltrating, myeloma-specific T cells in a mouse model of multiple myeloma. In vivo, only cells expanded from PD-1(+) CD8 TILs contained tumor progression, and their efficacy was enhanced by PDL-1 blockade. Overall, our data provide a rationale for the use of PD-1-selected TILs in ACT. (C) 2017 AACR.
Autores: Carrasco, A.; Ezponda, Teresa; Meydan, C.; et al.
Revista: HAEMATOLOGICA-THE HEMATOLOGY JOURNAL
ISSN 0390-6078  Vol. 102  Nº Supl. 4  2017  págs. 10
Autores: Ezponda, Teresa; Meydan, C.; et al.
Revista: HAEMATOLOGICA
ISSN 0390-6078  Vol. 102  Nº Supl. 2  2017  págs. 502 - 502
Autores: Cuenca, I. ; Sanchez-Vega, B.; Lourenco, Bruno David; et al.
Revista: HAEMATOLOGICA
ISSN 0390-6078  Vol. 102  Nº Supl.2  2017  págs. 106
Autores: Alfaro, Carlos; et al.
Revista: CLINICAL CANCER RESEARCH
ISSN 1078-0432  Vol. 22  Nº 15  2016  págs. 3924 - 3936
PURPOSE: Myeloid-derived suppressor cells (MDSC) are considered an important T-cell immunosuppressive component in cancer-bearing hosts. The factors that attract these cells to the tumor microenvironment are poorly understood. IL8 (CXCL8) is a potent chemotactic factor for neutrophils and monocytes. EXPERIMENTAL DESIGN: MDSC were characterized and sorted by multicolor flow cytometry on ficoll-gradient isolated blood leucokytes from healthy volunteers (n = 10) and advanced cancer patients (n = 28). In chemotaxis assays, sorted granulocytic and monocytic MDSC were tested in response to recombinant IL8, IL8 derived from cancer cell lines, and patient sera. Neutrophil extracellular traps (NETs) formation was assessed by confocal microscopy, fluorimetry, and time-lapse fluorescence confocal microscopy on short-term MDSC cultures. RESULTS: IL8 chemoattracts both granulocytic (GrMDSC) and monocytic (MoMDSC) human MDSC. Monocytic but not granulocytic MDSC exerted a suppressor activity on the proliferation of autologous T cells isolated from the circulation of cancer patients. IL8 did not modify the T-cell suppressor activity of human MDSC. However, IL8 induced the formation of NETs in the GrMDSC subset. CONCLUSIONS: IL8 derived from tumors contributes to the chemotactic recruitment of MDSC and to their functional control.
Autores: Lourenco, Bruno David; Martinez-Lopez, J.; Corchete, L. A. ; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 127  Nº 24  2016  págs. 3035 - 3039
Immunoglobulin light-chain amyloidosis (AL) and multiple myeloma (MM) are 2 distinct monoclonal gammopathies that involve the same cellular compartment: clonal plasma cells (PCs). Despite the fact that knowledge about MM PC biology has significantly increased in the last decade, the same does not apply for AL. Here, we used an integrative phenotypic, molecular, and genomic approach to study clonal PCs from 24 newly diagnosed patients with AL. Through principal-component-analysis, we demonstrated highly overlapping phenotypic profiles between AL and both monoclonal gammopathy of undetermined significance and MM PCs. However, in contrast to MM, highly purified fluorescence-activated cell-sorted clonal PCs from AL (n = 9) showed almost normal transcriptome, with only 38 deregulated genes vs normal PCs; these included a few tumor-suppressor (CDH1, RCAN) and proapoptotic (GLIPR1, FAS) genes. Notwithstanding, clonal PCs in AL (n=11) were genomically unstable, with a median of 9 copy number alterations (CNAs) per case, many of such CNAs being similar to those found in MM. Whole-exome sequencing (WES) performed in 5 AL patients revealed a median of 15 nonrecurrent mutations per case. Altogether, our results show that in the absence of a unifying mutation by WES, clonal PCs in AL display phenotypic and CNA profiles similar to MM, but their transcriptome is remarkably similar to that of normal PCs.
Autores: Lourenco, Bruno David; Puig, N. ; Cedena, M. T.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 128  Nº 22  2016 
Autores: Moreno, L.; Zabaleta, Aintzane; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 128  Nº 22  2016 
Autores: Bretones, G.; Lourenco, Bruno David; Valdes-Mas, R.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 128  Nº 22  2016 
Autores: Burgos, Leire; Garcés, Juan-José; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 128  Nº 22  2016 
Autores: Carrasco, A.; Ezponda, Teresa; Meydan, C.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 128  Nº 22  2016 
Autores: Kulis, M.; Merkel, A.; Heath, S.; et al.
Revista: NATURE GENETICS
ISSN 1061-4036  Vol. 47  Nº 7  2015  págs. 746 -56
We analyzed the DNA methylome of ten subpopulations spanning the entire B cell differentiation program by whole-genome bisulfite sequencing and high-density microarrays. We observed that non-CpG methylation disappeared upon B cell commitment, whereas CpG methylation changed extensively during B cell maturation, showing an accumulative pattern and affecting around 30% of all measured CpG sites. Early differentiation stages mainly displayed enhancer demethylation, which was associated with upregulation of key B cell transcription factors and affected multiple genes involved in B cell biology. Late differentiation stages, in contrast, showed extensive demethylation of heterochromatin and methylation gain at Polycomb-repressed areas, and genes with apparent functional impact in B cells were not affected. This signature, which has previously been linked to aging and cancer, was particularly widespread in mature cells with an extended lifespan. Comparing B cell neoplasms with their normal counterparts, we determined that they frequently acquire methylation changes in regions already undergoing dynamic methylation during normal B cell differentiation.
Autores: Mishima, Y. ; Lourenco, Bruno David; Shi, J.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 126  Nº 23  2015 
Autores: Kulis, M.; Heath, S.; Castellano, G.; et al.
Revista: BLOOD
ISSN 0006-4971  Vol. 124  Nº 21  2014