Grupos de investigación

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12105/19597

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CREBBP/EP300 Bromodomain Inhibition Affects the Proliferation of AR-Positive Breast Cancer Cell Lines.
(AMER ASSOC CANCER RESEARCH, 2019-03) Garcia-Carpizo, Veronica; Ruiz-Llorente, Sergio; Sarmentero, Jacinto; González-Corpas, Ana; Barrero, Maria J
Inhibitors that prevent the binding of bromodomains to acetylated histones hold therapeutic potential. However, the effects of targeting most of the 60 different bromodomains found in the human proteome remain unexplored. Here, we investigate the molecular mechanisms responsible for the antiproliferative properties of CREBBP/EP300 bromodomain inhibition in ER-negative breast cancer cell lines. We show using genetic and chemical approaches that CREBBP/EP300 bromodomains are critical to support the proliferation of the triple-negative breast cancer cell line MDA-MB-453. Analysis of the transcriptional pathways affected by CREBBP/EP300 bromodomain inhibitors reveals that the expression of genes associated with super-enhancers is downregulated, which in turn are occupied by very high levels of androgen receptor (AR) in MDA-MB-453 cells. Treatment of MDA-MB-453 with CREBBP/EP300 bromodomain inhibitors downregulates the expression of an AR-dependent signature distinctive of breast cancer tumors that express AR and causes a decrease in H3K27ac levels at AR-binding sites. In accordance, in prostate cancer cell lines that express AR CREBBP/EP300 bromodomain inhibitors downregulate the expression of genes bound by AR and associated with super-enhancers. In summary, we report that triple-negative breast cancer cell lines that express AR are particularly sensitive to CREBBP/EP300 bromodomain inhibitors and consequently these inhibitors hold potential to treat this type of cancer. IMPLICATIONS: AR-dependent cancer cell lines are sensitive to CREBBP/EP300 bromodomain inhibitors.
Epigenetic Regulation of Gfi1 in Endocrine-Related Cancers: a Role Regulating Tumor Growth.
(MPDI, 2020-06-30) Ashour, Nadia; Angulo, Javier C; González-Corpas, Ana; Orea, María J; Lobo, María V T; Colomer, Ramón; Colás, Begoña; Esteller, Manel; Ropero, Santiago
Prostate and breast cancer constitute the most common cancers among men and women worldwide. The aging population is one of the main risk factors for prostate and breast cancer development and accumulating studies link aging with epigenetic changes. Growth factor independence-1 (Gfi1) is a transcriptional repressor with an important role in human malignancies, including leukemia, colorectal carcinoma, and lung cancer, but its role in prostate and breast cancer is unknown. We have found that Gfi1 epigenetic silencing is a common event in prostate and breast cancer. Gfi1 re-expression in prostate and breast cancer cell lines displaying Gfi1 epigenetic silencing decreases cell proliferation, reduced colony formation density, and tumor growth in nude mice xenografts. In addition, we found that Gfi1 repress alpha 1-anti-trypsin (AAT) and alpha 1-anti-chymotrypsin (ACT) expression, two genes with important functions in cancer development, suggesting that Gfi1 silencing promotes tumor growth by increasing AAT and ACT expression in our system. Finally, Gfi1 epigenetic silencing could be a promising biomarker for prostate cancer progression because it is associated with shorter disease-free survival. In conclusion, our findings strongly indicate that Gfi1 epigenetic silencing in prostate and breast cancer could be a crucial step in the development of these two-well characterized endocrine related tumors.
A novel high-content analysis tool reveals Rab8-driven cytoskeletal reorganization through Rho GTPases, calpain and MT1-MMP.
(COMPANY BIOLOGISTS LTD, 2016-04-15) Bravo-Cordero, José J; Cordani, Marco; Soriano, Silvia F; Díez, Begoña; Muñoz-Agudo, Carmen; Casanova-Acebes, Maria; Boullosa, César; Guadamillas, Marta C; Ezkurdia, Iakes; González-Pisano, David; Del Pozo, Miguel A; Montoya, María C
Rab8 is a small Ras-related GTPase that regulates polarized membrane transport to the plasma membrane. Here, we developed a high-content analysis (HCA) tool to dissect Rab8-mediated actin and focal adhesion reorganization that revealed that Rab8 activation significantly induced Rac1 and Tiam1 to mediate cortical actin polymerization and RhoA-dependent stress fibre disassembly. Rab8 activation increased Rac1 activity, whereas its depletion activated RhoA, which led to reorganization of the actin cytoskeleton. Rab8 was also associated with focal adhesions, promoting their disassembly in a microtubule-dependent manner. This Rab8 effect involved calpain, MT1-MMP (also known as MMP14) and Rho GTPases. Moreover, we demonstrate the role of Rab8 in the cell migration process. Indeed, Rab8 is required for EGF-induced cell polarization and chemotaxis, as well as for the directional persistency of intrinsic cell motility. These data reveal that Rab8 drives cell motility by mechanisms both dependent and independent of Rho GTPases, thereby regulating the establishment of cell polarity, turnover of focal adhesions and actin cytoskeleton rearrangements, thus determining the directionality of cell migration.
The nuclear receptor LXRα controls the functional specialization of splenic macrophages.
(NATURE PORTFOLIO, 2013-08) A-Gonzalez, Noelia; Guillen, Jose A; Gallardo, Germán; Diaz, Mercedes; de la Rosa, Juan V; Hernandez, Irene H; Casanova-Acebes, Maria; Lopez, Felix; Tabraue, Carlos; Beceiro, Susana; Hong, Cynthia; Lara, Pedro C; Andujar, Miguel; Arai, Satoko; Miyazaki, Toru; Li, Senlin; Corbi, Angel L; Tontonoz, Peter; Hidalgo, Andres; Castrillo, Antonio
Macrophages are professional phagocytic cells that orchestrate innate immune responses and have considerable phenotypic diversity at different anatomical locations. However, the mechanisms that control the heterogeneity of tissue macrophages are not well characterized. Here we found that the nuclear receptor LXRα was essential for the differentiation of macrophages in the marginal zone (MZ) of the spleen. LXR-deficient mice were defective in the generation of MZ and metallophilic macrophages, which resulted in abnormal responses to blood-borne antigens. Myeloid-specific expression of LXRα or adoptive transfer of wild-type monocytes restored the MZ microenvironment in LXRα-deficient mice. Our results demonstrate that signaling via LXRα in myeloid cells is crucial for the generation of splenic MZ macrophages and identify an unprecedented role for a nuclear receptor in the generation of specialized macrophage subsets.
Melanoma-derived small extracellular vesicles induce lymphangiogenesis and metastasis through an NGFR-dependent mechanism.
(NATURE PORTFOLIO, 2021-12) García-Silva, Susana; Benito-Martín, Alberto; Nogués, Laura; Hernández-Barranco, Alberto; Mazariegos, Marina S; Santos, Vanesa; Hergueta-Redondo, Marta; Ximénez-Embún, Pilar; Kataru, Raghu P; Lopez, Ana Amor; Merino, Cristina; Sánchez-Redondo, Sara; Graña-Castro, Osvaldo; Matei, Irina; Nicolás-Avila, José Ángel; Torres-Ruiz, Raúl; Rodríguez-Perales, Sandra; Martínez, Lola; Pérez-Martínez, Manuel; Mata, Gadea; Szumera-Ciećkiewicz, Anna; Kalinowska, Iwona; Saltari, Annalisa; Martínez-Gómez, Julia M; Hogan, Sabrina A; Saragovi, H Uri; Ortega Jimenez, Sagrario; Garcia-Martin, Carmen; Levesque, Mitchell P; Rutkowski, Piotr; Hidalgo, Andrés; Muñoz, Javier; Megías, Diego; Mehrara, Babak J; Lyden, David; Peinado Selgas, Hector
Secreted extracellular vesicles (EVs) influence the tumor microenvironment and promote distal metastasis. Here, we analyzed the involvement of melanoma-secreted EVs in lymph node pre-metastatic niche formation in murine models. We found that small EVs (sEVs) derived from metastatic melanoma cell lines were enriched in nerve growth factor receptor (NGFR, p75NTR), spread through the lymphatic system and were taken up by lymphatic endothelial cells, reinforcing lymph node metastasis. Remarkably, sEVs enhanced lymphangiogenesis and tumor cell adhesion by inducing ERK kinase, nuclear factor (NF)-κB activation and intracellular adhesion molecule (ICAM)-1 expression in lymphatic endothelial cells. Importantly, ablation or inhibition of NGFR in sEVs reversed the lymphangiogenic phenotype, decreased lymph node metastasis and extended survival in pre-clinical models. Furthermore, NGFR expression was augmented in human lymph node metastases relative to that in matched primary tumors, and the frequency of NGFR metastatic melanoma cells in lymph nodes correlated with patient survival. In summary, we found that NGFR is secreted in melanoma-derived sEVs, reinforcing lymph node pre-metastatic niche formation and metastasis.
Stem cells & pancreatic cancer.
(2013) García-Silva, Susana; Frias-Aldeguer, Javier; Heeschen, Christopher
It is now well established that human pancreatic ductal adenocarcinoma (PDAC) contains a subset of cells with self-renewal capabilities and subsequent exclusive in vivo tumorigenic capacity as assessed by limiting dilution tumorigenic transplantation assays into immunodeficient mice. These cells are considered pancreatic cancer stem cells (CSCs) and are able to form tumors indistinguishable from parental ones. Furthermore they display strong chemotherapy resistance and are implicated in tumor relapses and metastatic spread. Important next steps for advancing the field of pancreatic CSC research include the identification and characterization of CSCs in the unperturbed in vivo setting. This has been achieved just recently for other solid tumors such as glioblastoma using clonal analysis after lineage tracing in mice [1]. In vivo imaging of CSCs during tumor development should not only provide new insights into the in vivo features of CSCs, but also help to further unravel the influence of the stroma on CSC biology. Comprehensive studies of the tumor heterogeneity with respect to the coexistence of different clones potentially generated by distinct population of CSCs that are evolving by stochastic cell fate decisions may actually unite the CSC concept and the model of clonal evolution for pancreatic cancer. Eventually, the design of specific therapies against CSCs should open new alleys to improve survival of patients with PDAC. Combined therapies targeting CSCs and their progenies as well as the supportive stroma may represent the most promising approach for the future treatment of patients with PDAC.
Thyroid hormone receptor β1 domains responsible for the antagonism with the ras oncogene: role of corepressors.
(2011-02-17) García-Silva, S; Martínez-Iglesias, O; Ruiz-Llorente, L; Aranda, A
The thyroid hormone receptor (TR) is a suppressor of ras-mediated responses. To characterize the receptor domains involved in this function, we analyzed a panel of TRβ1 mutants for their ability to interfere with ras-driven cyclin D1 activation, formation of transformation foci and tumor growth in nude mice. Our results show that the domains and mechanisms responsible for the anti-transforming and anti-tumorigenic actions of the receptor are divergent from those operating in classical T3-dependent transcriptional activation. TRβ1 mutants that do not bind coactivators and do not transactivate retained the capacity of suppressing cellular transformation and tumor growth, whereas selective mutations in the hinge region affecting corepressors recruitment abolished these actions, while preserving ligand-dependent transcription. There was a strict parallelism between anti-transforming activity of the various mutants and their ability to antagonize cyclin D1 stimulation by ras, indicating that transrepression mechanisms may have an important function in suppression of the transforming effects of the oncogene by TRβ1. The inhibitory action of T3 on transformation was further enhanced after over-expression of corepressors, while corepressor depletion by means of small-interference RNA reversed significantly hormonal action. This shows an important functional role of endogenous corepressors in suppression of ras-mediated transformation and tumorigenesis by TRβ1.
The thyroid hormone receptor is a suppressor of ras-mediated transcription, proliferation, and transformation.
(TAYLOR & FRANCIS INC, 2004-09) García-Silva, Susana; Aranda, Ana
The thyroid hormone triiodothyronine (T3) has a profound effect on growth, differentiation, and metabolism in higher organisms. Here we demonstrate that T3 inhibits ras-induced proliferation in neuroblastoma cells and blocks induction of cyclin D1 expression by the oncogene. The hormone, at physiological concentrations, strongly antagonizes the transcriptional response mediated by the Ras/mitogen-activated protein kinase/ribosomal-S6 subunit kinase (Rsk) signaling pathway in cells expressing thyroid hormone receptors (TRs). T3 blocks the response to the oncogenic forms of the three ras isoforms (H-, K-, and N-ras) and both TRalpha and TRbeta can mediate this action. The main target for induction of cyclin D1 transcription by oncogenic ras in neuroblastoma cells is a cyclic AMP response element (CRE) located in proximal promoter sequences, and T3 represses the transcriptional activity of b-Zip transcription factors such as CREB (CRE-binding protein) or ATF-2 (activation transcription factor 2) that are direct targets of Rsk2 and bind to this sequence. The hormone also blocks fibroblast transformation by oncogenic ras when TR is expressed. Furthermore, TRs act as suppressors of tumor formation by the oncogene in vivo in nude mice. The TRbeta isoform has stronger antitransforming properties than the alpha isoform and can inhibit tumorigenesis even in hypothyroid mice. These results show the existence of a previously unrecognized transcriptional cross talk between the TRs and the ras oncogene which influences relevant processes such as cell proliferation, transformation, or tumorigenesis.
Cell cycle control by the thyroid hormone in neuroblastoma cells.
(ELSEVIER IRELAND LTD, 2002-12-27) Garcia-Silva, Susana; Perez-Juste, German; Aranda, Ana
The thyroid hormone (T3) blocks proliferation and induces differentiation of neuroblastoma N2a-beta cells that overexpress the beta 1 isoform of the T3 receptor. An element in the region responsible for premature termination of transcription mediates a rapid repression of c-myc gene expression by T3. The hormone also causes a decrease of cyclin D1 gene transcription, and is able to antagonize the activation of the cyclin D1 promoter by Ras. In addition, a strong and sustained increase of the levels of the cyclin kinase inhibitor (CKI) p27(Kip1) are found in T3-treated cells. The increased levels of p27(Kip1) lead to a marked inhibition of the kinase activity of the cyclin-CDK2 complexes. As a consequence of these changes, retinoblastoma proteins are hypophosphorylated in T3-treated N2a-beta cells, and progression through the restriction point in the cell cycle is blocked.
Identification of kinase fusion oncogenes in post-Chernobyl radiation-induced thyroid cancers.
(2013-11) Montero-Conde, Cristina; Ricarte-Filho, Julio C; Li, Sheng; Garcia-Rendueles, Maria E R; Montero-Conde, Cristina; Voza, Francesca; Knauf, Jeffrey A; Heguy, Adriana; Viale, Agnes; Bogdanova, Tetyana; Thomas, Geraldine A; Mason, Christopher E; Fagin, James A
Exposure to ionizing radiation during childhood markedly increases the risk of developing papillary thyroid cancer. We examined tissues from 26 Ukrainian patients with thyroid cancer who were younger than 10 years of age and living in contaminated areas during the time of the Chernobyl nuclear reactor accident. We identified nonoverlapping somatic driver mutations in all 26 cases through candidate gene assays and next-generation RNA sequencing. We found that 22 tumors harbored fusion oncogenes that arose primarily through intrachromosomal rearrangements. Altogether, 23 of the oncogenic drivers identified in this cohort aberrantly activate MAPK signaling, including the 2 somatic rearrangements resulting in fusion of transcription factor ETS variant 6 (ETV6) with neurotrophic tyrosine kinase receptor, type 3 (NTRK3) and fusion of acylglycerol kinase (AGK) with BRAF. Two other tumors harbored distinct fusions leading to overexpression of the nuclear receptor PPARγ. Fusion oncogenes were less prevalent in tumors from a cohort of children with pediatric thyroid cancers that had not been exposed to radiation but were from the same geographical regions. Radiation-induced thyroid cancers provide a paradigm of tumorigenesis driven by fusion oncogenes that activate MAPK signaling or, less frequently, a PPARγ-driven transcriptional program.
Overexpression and activation of EGFR and VEGFR2 in medullary thyroid carcinomas is related to metastasis.
(BIOSCIENTIFICA LTD, 2010-03) Rodriguez Antona, Cristina; Pallares, Judith; Montero-Conde, Cristina; Inglada-Pérez, Lucia; Castelblanco, Esmeralda; Landa, Iñigo; Leskelä, Susanna; Leandro-García, Luis J; López-Jiménez, Elena; Letón, Rocío; Cascon Soriano, Alberto; Lerma, Enrique; Martin, M Carmen; Carralero, M Carmen; Mauricio, Didac; Cigudosa, Juan Cruz; Matias-Guiu, Xavier; Robledo Batanero, Mercedes; Instituto de Salud Carlos III; CIBERER
Therapeutic options for patients with metastatic medullary thyroid carcinoma (MTC) are limited due to lack of effective treatments. Thus, there is a need to thoroughly characterize the pathways of molecular pathogenesis and to identify potential targets for therapy in MTC. Since epidermal growth factor receptor (EGFR) seems to play a crucial role for RET activation, a key feature of MTCs, and several promising EGFR/vascular endothelial growth factor receptor 2 (VEGFR2)-targeted drugs have been developed, the present study was designed to investigate whether these proteins are altered in MTCs. We used a well-characterized series of 153 MTCs to evaluate EGFR activation by sequencing and FISH analysis, and to perform EGFR and VEGFR2 immunohistochemistry. EGFR tyrosine kinase domain mutations were not a feature of MTCs; however, EGFR polysomy and a strong EGFR expression were detected in 15 and 13% of the tumors respectively. Interestingly, EGFR was significantly overexpressed in metastases compared with primary tumors (35 vs 9%, P=0.002). We also studied whether specific RET mutations were associated with EGFR status, and found a decrease in EGFR polysomies (P=0.006) and a tendency towards lower EGFR expression for the most aggressive RET mutations (918, 883). Concerning VEGFR2, metastasis showed a higher expression than primary tumors (P=2.8 x 10(-8)). In this first study investigating the relationship between EGFR, RET, and VEGFR2 in a large MTC series, we found an activation of EGFR and VEGFR2 in metastasis, using both independent and matched primary/metastasis samples. This suggests that some MTC patients may benefit from existing anti-EGFR/VEFGR2 therapies, although additional preclinical and clinical evidence is needed.
Multilayer OMIC Data in Medullary Thyroid Carcinoma Identifies the STAT3 Pathway as a Potential Therapeutic Target in Tumors.
(2017-03-01) Mancikova, Veronika; Montero-Conde, Cristina; Perales-Paton, Javier; Fernandez, Agustin; Santacana, María; Jodkowska, Karolina; Inglada-Pérez, Lucia; Castelblanco, Esmeralda; Borrego, Salud; Encinas, Mario; Matias-Guiu, Xavier; Fraga, Mario; Robledo Batanero, Mercedes; European Union (EU); Instituto de Salud Carlos III; Comunidad de Madrid; Centro de Investigacion Biomedica en Red de Enfermedades Raras (CIBERER); AECC; LA CAIXA
Medullary thyroid carcinoma (MTC) is a rare disease with few genetic drivers, and the etiology specific to each known susceptibility mutation remains unknown. Exploiting multilayer genomic data, we focused our interest on the role of aberrant DNA methylation in MTC development. We performed genome-wide DNA methylation profiling assessing more than 27,000 CpGs in the largest MTC series reported to date, comprising 48 molecularly characterized tumors. mRNA and miRNA expression data were available for 33 and 31 tumors, respectively. Two human MTC cell lines and 101 paraffin-embedded MTCs were used for validation. The most distinctive methylome was observed for -related tumors. Integration of methylation data with mRNA and miRNA expression data identified genes negatively regulated by promoter methylation. These findings were confirmed for , and miR-10a, -30a, and -200c. The mutation-specific aberrant methylation of , and was validated in 25 independent MTCs by bisulfite pyrosequencing. The methylome and transcriptome data underscored JAK/Stat pathway involvement in MTCs. Immunostaining [immunohistochemistry (IHC)] for the active form of signaling effector STAT3 was performed in a series of 101 MTCs. As expected, positive IHC was associated with -bearing tumors ( < 0.02). Pharmacologic inhibition of STAT3 activity increased the sensitivity to vandetanib of the -positive MTC cell line, MZ-CRC-1. Multilayer OMIC data analysis uncovered methylation hallmarks in genetically defined MTCs and revealed JAK/Stat signaling effector STAT3 as a potential therapeutic target for the treatment of MTCs. .
Exploiting the intrinsic misfolding propensity of the KRAS oncoprotein.
(NATL ACAD SCIENCES, 2023-02-28) Janssen, Kobe; Claes, Filip; Van de Velde, Dido; Wehbi, Vanessa L; Houben, Bert; Lampi, Yulia; Nys, Mieke; Khodaparast, Laleh; Khodaparast, Ladan; Louros, Nikolaos; van der Kant, Rob; Verniers, Joffre; Garcia, Teresa; Ramakers, Meine; Konstantoulea, Katerina; Maragkou, Katerina; Duran-Romaña, Ramon; Musteanu, Mónica; Barbacid, Mariano; Scorneaux, Bernard; Beirnaert, Els; Schymkowitz, Joost; Rousseau, Frederic; Flanders Innovation and Entrepreneurship (VLAIO); VIB - KU Leuven Center for Brain & Disease Research; FWO
Mutant KRAS is a major driver of oncogenesis in a multitude of cancers but remains a challenging target for classical small molecule drugs, motivating the exploration of alternative approaches. Here, we show that aggregation-prone regions (APRs) in the primary sequence of the oncoprotein constitute intrinsic vulnerabilities that can be exploited to misfold KRAS into protein aggregates. Conveniently, this propensity that is present in wild-type KRAS is increased in the common oncogenic mutations at positions 12 and 13. We show that synthetic peptides (Pept-ins™) derived from two distinct KRAS APRs could induce the misfolding and subsequent loss of function of oncogenic KRAS, both of recombinantly produced protein in solution, during cell-free translation and in cancer cells. The Pept-ins exerted antiproliferative activity against a range of mutant KRAS cell lines and abrogated tumor growth in a syngeneic lung adenocarcinoma mouse model driven by mutant KRAS G12V. These findings provide proof-of-concept that the intrinsic misfolding propensity of the KRAS oncoprotein can be exploited to cause its functional inactivation.
p53 and ovarian carcinoma survival: an Ovarian Tumor Tissue Analysis consortium study.
(2023-05) Köbel, Martin; Kang, Eun-Young; Weir, Ashley; Rambau, Peter F; Lee, Cheng-Han; Nelson, Gregg S; Ghatage, Prafull; Meagher, Nicola S; Riggan, Marjorie J; Alsop, Jennifer; Anglesio, Michael S; Beckmann, Matthias W; Bisinotto, Christiani; Boisen, Michelle; Boros, Jessica; Brand, Alison H; Brooks-Wilson, Angela; Carney, Michael E; Coulson, Penny; Courtney-Brooks, Madeleine; Cushing-Haugen, Kara L; Cybulski, Cezary; Deen, Suha; El-Bahrawy, Mona A; Elishaev, Esther; Erber, Ramona; Fereday, Sian; Fischer, Anna; Gayther, Simon A; Barquin-Garcia, Arantzazu; Gentry-Maharaj, Aleksandra; Gilks, C Blake; Gronwald, Helena; Grube, Marcel; Harnett, Paul R; Harris, Holly R; Hartkopf, Andreas D; Hartmann, Arndt; Hein, Alexander; Hendley, Joy; Hernandez, Brenda Y; Huang, Yajue; Jakubowska, Anna; Jimenez-Linan, Mercedes; Jones, Michael E; Kennedy, Catherine J; Kluz, Tomasz; Koziak, Jennifer M; Lesnock, Jaime; Lester, Jenny; Lubiński, Jan; Longacre, Teri A; Lycke, Maria; Mateoiu, Constantina; McCauley, Bryan M; McGuire, Valerie; Ney, Britta; Olawaiye, Alexander; Orsulic, Sandra; Osorio, Ana; Paz-Ares, Luis; Ramón Y Cajal, Teresa; Rothstein, Joseph H; Ruebner, Matthias; Schoemaker, Minouk J; Shah, Mitul; Sharma, Raghwa; Sherman, Mark E; Shvetsov, Yurii B; Singh, Naveena; Steed, Helen; Storr, Sarah J; Talhouk, Aline; Traficante, Nadia; Wang, Chen; Whittemore, Alice S; Widschwendter, Martin; Wilkens, Lynne R; Winham, Stacey J; Benitez, Javier; Berchuck, Andrew; Bowtell, David D; Candido Dos Reis, Francisco J; Campbell, Ian; Cook, Linda S; DeFazio, Anna; Doherty, Jennifer A; Fasching, Peter A; Fortner, Renée T; García, María J; Goodman, Marc T; Goode, Ellen L; Gronwald, Jacek; Huntsman, David G; Karlan, Beth Y; Kelemen, Linda E; Kommoss, Stefan; Le, Nhu D; Martin, Stewart G; Menon, Usha; Modugno, Francesmary; Pharoah, Paul Dp; Schildkraut, Joellen M; Sieh, Weiva; Staebler, Annette; Sundfeldt, Karin; Swerdlow, Anthony J; Ramus, Susan J; Brenton, James D; Alberta Precision Laboratory research support fund; United States Department of Defense United States Army U.S. Army Medical Research & Materiel Command (USAMRMC); Canadian Institutes of Health Research (CIHR) Cancer Council Victoria; National Health & Medical Research Council (NHMRC) of Australia; Instituto de Salud Carlos III; European Union (EU); Spanish Network on Rare Diseases (CIBERER); Cancer Research UK
Our objective was to test whether p53 expression status is associated with survival for women diagnosed with the most common ovarian carcinoma histotypes (high-grade serous carcinoma [HGSC], endometrioid carcinoma [EC], and clear cell carcinoma [CCC]) using a large multi-institutional cohort from the Ovarian Tumor Tissue Analysis (OTTA) consortium. p53 expression was assessed on 6,678 cases represented on tissue microarrays from 25 participating OTTA study sites using a previously validated immunohistochemical (IHC) assay as a surrogate for the presence and functional effect of TP53 mutations. Three abnormal expression patterns (overexpression, complete absence, and cytoplasmic) and the normal (wild type) pattern were recorded. Survival analyses were performed by histotype. The frequency of abnormal p53 expression was 93.4% (4,630/4,957) in HGSC compared to 11.9% (116/973) in EC and 11.5% (86/748) in CCC. In HGSC, there were no differences in overall survival across the abnormal p53 expression patterns. However, in EC and CCC, abnormal p53 expression was associated with an increased risk of death for women diagnosed with EC in multivariate analysis compared to normal p53 as the reference (hazard ratio [HR] = 2.18, 95% confidence interval [CI] 1.36-3.47, p = 0.0011) and with CCC (HR = 1.57, 95% CI 1.11-2.22, p = 0.012). Abnormal p53 was also associated with shorter overall survival in The International Federation of Gynecology and Obstetrics stage I/II EC and CCC. Our study provides further evidence that functional groups of TP53 mutations assessed by abnormal surrogate p53 IHC patterns are not associated with survival in HGSC. In contrast, we validate that abnormal p53 IHC is a strong independent prognostic marker for EC and demonstrate for the first time an independent prognostic association of abnormal p53 IHC with overall survival in patients with CCC.
The influence of extracellular vesicles on tumor evolution and resistance to therapy
(2025-02) Bastón , E; García-Agulló, J; Peinado, H; Ministerio de Ciencia e Innovación (España); ASOCIACIÓN ESPAÑOLA CONTRA EL CÁNCER
Disruption of cellular communication that regulates normal physiology is often key factor in the development of disease, including cancer. Extracellular vesicles (EVs) are mediators of cell-cell communication, modulating local and distant microenvironments and playing an important role influencing tumor progression at both early and late stages. Indeed, EV-mediated communication participate in the initial steps of primary tumor transformation and proliferation, as well as the preparation of the pre-metastatic niche and subsequent metastasis. In this context, the presence of DNA in EVs (EV-DNA) is particularly intriguing, with important biological implications and significant potential as a biomarker in liquid biopsies. In this review we will discuss the mechanisms involved in EV-shed DNA and the potential impact in tumor evolution. In addition, it has become apparent in recent years that the secretion of EVs also influences the behavior of the surrounding microenvironment. An important unresolved challenge in oncology is the resistance of tumors to treatment, one of the primary causes of high cancer mortality. The role of EVs in therapy resistance has garnered considerable interest. In the later part of this review, we will also examine the potential involvement of EVs in resistance to therapy.
Molecular cytogenetic characterization of rhabdomyosarcoma cell lines.
(Elsevier, 2004-01-01) Rodriguez Perales, Sandra; Martínez-Ramírez, Angel; de Andrés, Sara Alvarez; Valle, Laura; Urioste, Miguel; Benítez, Javier; Cigudosa, Juan C
Alveolar rhabdomyosarcomas (ARMS) are soft-tissue tumors that are genetically characterized by the presence of reciprocal translocations that generate the fusion gene PAX3-FOXO1A or PAX7-FOXO1A. For the study of the biologic consequences of such rearrangements, several cell lines have been generated. However, established cell lines accumulate chromosome and genetic aberrations that make it difficult to draw significant conclusions. We have applied a set of techniques that includes spectral karyotyping, fluorescence in situ hybridization (FISH), comparative genomic hybridization (CGH), and microarray CGH, to the most commonly used cell lines carrying the two fusion genes that are present in ARMS. We have identified the bacterial artificial chromosomes that cover the breakpoints at genes PAX3, PAX7, and FOXO1A, which can be used as FISH probes for the translocations. The RH30 cell line, positive for the PAX3-FOXO1A fusion gene, was found to be highly complex: wide range of chromosome number, more than 50 chromosome rearrangements, amplification of the hybrid gene, 24 DNA changes detected by conventional CGH, and 21 gene copy changes detected by microarray CGH (including several high-level amplifications). RMZ-RC2 cell line, positive for the PAX7-FOXO1A, was in the near-tetraploid range with only nonclonal structural rearrangements, amplification of the hybrid gene, 24 DNA changes by CGH, and 8 gene copy changes, confirming the previously reported high-level amplification of MYCN.
Phenotypic characterization of BRCA1 and BRCA2 tumors based in a tissue microarray study with 37 immunohistochemical markers.
(Springuer, 2005-03) Palacios, José; Honrado, Emiliano; Osorio, Ana; Cazorla, Alicia; Sarrió, David; Barroso, Alicia; Rodriguez Perales, Sandra; Cigudosa, Juan C; Diez, Orland; Alonso, Carmen; Lerma, Enrique; Dopazo, Joaquín; Rivas, Carmen; Benítez, Javier
Familial breast cancers that are associated with BRCA1 or BRCA2 germline mutations differ in both their morphological and immunohistochemical characteristics. To further characterize the molecular difference between genotypes, the authors evaluated the expression of 37 immunohistochemical markers in a tissue microarray (TMA) containing cores from 20 BRCA1, 14 BRCA2, and 59 sporadic age-matched breast carcinomas. Markers analyzed included, amog others, common markers in breast cancer, such as hormone receptors, p53 and HER2, along with 15 molecules involved in cell cycle regulation, such as cyclins, cyclin dependent kinases (CDK) and CDK inhibitors (CDKI), apoptosis markers, such as BCL2 and active caspase 3, and two basal/myoepithelial markers (CK 5/6 and P-cadherin). In addition, we analyzed the amplification of CCND1, CCNE, HER2 and MYC by FISH. Unsupervised cluster data analysis of both hereditary and sporadic cases using the complete set of immunohistochemical markers demonstrated that most BRCA1-associated carcinomas grouped in a branch of ER-, HER2-negative tumors that expressed basal cell markers and/or p53 and had higher expression of activated caspase 3. The cell cycle proteins associated with these tumors were E2F6, cyclins A, B1 and E, SKP2 and Topo IIalpha. In contrast, most BRCA2-associated carcinomas grouped in a branch composed by ER/PR/BCL2-positive tumors with a higher expression of the cell cycle proteins cyclin D1, cyclin D3, p27, p16, p21, CDK4, CDK2 and CDK1. In conclusion, our study in hereditary breast cancer tumors analyzing 37 immunohistochemical markers, define the molecular differences between BRCA1 and BRCA2 tumors with respect to hormonal receptors, cell cycle, apoptosis and basal cell markers.
Renal Lipotoxicity-Associated Inflammation and Insulin Resistance Affects Actin Cytoskeleton Organization in Podocytes.
(2015) Martínez-García, Cristina; Izquierdo-Lahuerta, Adriana; Vivas, Yurena; Velasco, Ismael; Yeo, Tet-Kin; Chen, Sheldon; Medina-Gomez, Gema
In the last few decades a change in lifestyle has led to an alarming increase in the prevalence of obesity and obesity-associated complications. Obese patients are at increased risk of developing hypertension, heart disease, insulin resistance (IR), dyslipidemia, type 2 diabetes and renal disease. The excess calories are stored as triglycerides in adipose tissue, but also may accumulate ectopically in other organs, including the kidney, which contributes to the damage through a toxic process named lipotoxicity. Recently, the evidence suggests that renal lipid accumulation leads to glomerular damage and, more specifically, produces dysfunction in podocytes, key cells that compose and maintain the glomerular filtration barrier. Our aim was to analyze the early mechanisms underlying the development of renal disease associated with the process of lipotoxicity in podocytes. Our results show that treatment of podocytes with palmitic acid produced intracellular accumulation of lipid droplets and abnormal glucose and lipid metabolism. This was accompanied by the development of inflammation, oxidative stress and endoplasmic reticulum stress and insulin resistance. We found specific rearrangements of the actin cytoskeleton and slit diaphragm proteins (Nephrin, P-Cadherin, Vimentin) associated with this insulin resistance in palmitic-treated podocytes. We conclude that lipotoxicity accelerates glomerular disease through lipid accumulation and inflammation. Moreover, saturated fatty acids specifically promote insulin resistance by disturbing the cytoarchitecture of podocytes. These data suggest that renal lipid metabolism and cytoskeleton rearrangements may serve as a target for specific therapies aimed at slowing the progression of podocyte failure during metabolic syndrome.
Inhibition of Rag GTPase signaling in mice suppresses B cell responses and lymphomagenesis with minimal detrimental trade-offs.
(Cell Press, 2021-07-13) Ortega-Molina, Ana; Lebrero-Fernández, Cristina; Sanz, Alba; Deleyto-Seldas, Nerea; Plata-Gómez, Ana Belén; Menéndez, Camino; Graña-Castro, Osvaldo; Caleiras, Eduardo; Efeyan, Alejo; Instituto de Salud Carlos III; Ministerio de Ciencia, Innovación y Universidades (España); Unión Europea
B lymphocytes are exquisitely sensitive to fluctuations in nutrient signaling by the Rag GTPases, and 15% of follicular lymphomas (FLs) harbor activating mutations in RRAGC. Hence, a potential therapeutic approach against malignant B cells is to inhibit Rag GTPase signaling, but because such inhibitors are still to be developed, efficacy and safety remain unknown. We generated knockin mice expressing a hypomorphic variant of RagC (Q119L); RagC mice are viable and show attenuated nutrient signaling. B lymphocyte activation is cell-intrinsically impaired in RagC mice, which also show significant suppression of genetically induced lymphomagenesis and autoimmunity. Surprisingly, no overt systemic trade-offs or phenotypic alterations caused by partial suppression of nutrient signaling are seen in other organs, and RagC mice show normal longevity and normal age-dependent health decline. These results support the efficacy and safety of moderate inhibition of nutrient signaling against pathological B cells.
Oncogenic Rag GTPase signaling enhances B cell activation and drives follicular lymphoma sensitive to pharmacological inhibition of mTOR.
(Nature Publishing Group, 2019-08) Ortega-Molina, Ana; Deleyto-Seldas, Nerea; Carreras, Joaquim; Sanz, Alba; Lebrero-Fernández, Cristina; Menéndez, Camino; Vandenberg, Andrew; Fernández-Ruiz, Beatriz; Marín-Arraiza, Leyre; de la Calle Arregui, Celia; Belén Plata-Gómez, Ana; Caleiras, Eduardo; de Martino, Alba; Martínez-Martín, Nuria; Troulé, Kevin; Piñeiro-Yáñez, Elena; Nakamura, Naoya; Araf, Shamzah; Victora, Gabriel D; Okosun, Jessica; Fitzgibbon, Jude; Efeyan, Alejo; Miniterio de Innovación, Ciencia y Universidades (España); EU-H2020 Programme
The humoral immune response demands that B cells undergo a sudden anabolic shift and high cellular nutrient levels which are required to sustain the subsequent proliferative burst. Follicular lymphoma (FL) originates from B cells that have participated in the humoral response, and 15% of FL samples harbor point, activating mutations in , an essential activator of mTORC1 downstream of the sensing of cellular nutrients. The impact of recurrent mutations in B cell function and lymphoma is unexplored. mutations, targeted to the endogenous locus in mice, confer a partial insensitivity to nutrient deprivation, but strongly exacerbate B cell responses and accelerate lymphomagenesis, while creating a selective vulnerability to pharmacological inhibition of mTORC1. This moderate increase in nutrient signaling synergizes with paracrine cues from the supportive T cell microenvironment that activates B cells via the PI3K-Akt-mTORC1 axis. Hence, mutations sustain induced germinal centers and murine and human FL in the presence of decreased T cell help. Our results support a model in which activating mutations in the nutrient signaling pathway foster lymphomagenesis by corrupting a nutrient-dependent control over paracrine signals from the T cell microenvironment.

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