Browsing by MeSH term "Neoplastic Stem Cells"
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Publication Aldh1 Expression and Activity Increase During Tumor Evolution in Sarcoma Cancer Stem Cell Populations(Nature Publishing Group, 2016) Martinez-Cruzado, Lucia; Tornin, Juan; Santos, Laura; Rodriguez, Aida; Garcia-Castro, Javier; Morís, Francisco; Rodriguez, Rene; Instituto de Salud Carlos III; Ministerio de Economía y Competitividad (España); Gobierno del Principado de Asturias (España)Tumors evolve from initial tumorigenic events into increasingly aggressive behaviors in a process usually driven by subpopulations of cancer stem cells (CSCs). Mesenchymal stromal/stem cells (MSCs) may act as the cell-of-origin for sarcomas, and CSCs that present MSC features have been identified in sarcomas due to their ability to grow as self-renewed floating spheres (tumorspheres). Accordingly, we previously developed sarcoma models using human MSCs transformed with relevant oncogenic events. To study the evolution/emergence of CSC subpopulations during tumor progression, we compared the tumorigenic properties of bulk adherent cultures and tumorsphere-forming subpopulations both in the sarcoma cell-of-origin models (transformed MSCs) and in their corresponding tumor xenograft-derived cells. Tumor formation assays showed that the tumorsphere cultures from xenograft-derived cells, but not from the cell-of-origin models, were enriched in CSCs, providing evidence of the emergence of bona fide CSCs subpopulations during tumor progression. Relevant CSC-related factors, such as ALDH1 and SOX2, were increasingly upregulated in CSCs during tumor progression, and importantly, the increased levels and activity of ALDH1 in these subpopulations were associated with enhanced tumorigenicity. In addition to being a CSC marker, our findings indicate that ALDH1 could also be useful for tracking the malignant potential of CSC subpopulations during sarcoma evolution.Publication BMPs as therapeutic targets and biomarkers in astrocytic glioma(Hindawi, 2014) Gonzalez-Gomez, Pilar; Anselmo, Nilson Praia; Mira, Helena; Comunidad de Madrid (España); Fundación Pedro Barrié de la MazaAstrocytic glioma is the most common brain tumor. The glioma initiating cell (GIC) fraction of the tumor is considered as highly chemoresistant, suggesting that GICs are responsible for glioma relapse. A potential treatment for glioma is to induce differentiation of GICs to a more benign and/or druggable cell type. Given BMPs are among the most potent inducers of GIC differentiation, they have been considered as noncytotoxic therapeutic compounds that may be of use to prevent growth and recurrence of glioma. We herein summarize advances made in the understanding of the role of BMP signaling in astrocytic glioma, with a particular emphasis on the effects exerted on GICs. We discuss the prognostic value of BMP signaling components and the implications of BMPs in the differentiation of GICs and in their sensitization to alkylating drugs and oncolytic therapy/chemotherapy. This mechanistic insight may provide new opportunities for therapeutic intervention of brain cancer.Publication Cancer stem cells from human glioblastoma resemble but do not mimic original tumors after in vitro passaging in serum-free media(Impact Journals, 2016) García-Romero, Noemí; González-Tejedo, Carmen; Carrión-Navarro, Josefa; Esteban-Rubio, Susana; Rackov, Gorjana; Rodríguez-Fanjul, Vanessa; Oliver-De La Cruz, Jorge; Prat-Acín, Ricardo; Peris-Celda, María; Blesa, David; Ramírez-Jiménez, Laura; Sánchez-Gómez, Pilar; Perona, Rosario; Escobedo-Lucea, Carmen; Belda-Iniesta, Cristobal; Ayuso-Sacido, Angel; Instituto de Salud Carlos III; Unión Europea. Fondo Europeo de Desarrollo Regional (FEDER/ERDF); Ministerio de Economía y Competitividad (España); Red Temática de Investigación Cooperativa en Cáncer (RTICC) (España)Human gliomas harbour cancer stem cells (CSCs) that evolve along the course of the disease, forming highly heterogeneous subpopulations within the tumour mass. These cells possess self-renewal properties and appear to contribute to tumour initiation, metastasis and resistance to therapy. CSC cultures isolated from surgical samples are considered the best preclinical in vitro model for primary human gliomas. However, it is not yet well characterized to which extent their biological and functional properties change during in vitro passaging in the serum-free culture conditions. Here, we demonstrate that our CSC-enriched cultures harboured from one to several CSC clones from the human glioma sample. When xenotransplanted into mouse brain, these cells generated tumours that reproduced at least three different dissemination patterns found in original tumours. Along the passages in culture, CSCs displayed increased expression of stem cell markers, different ratios of chromosomal instability events, and a varied response to drug treatment. Our findings highlight the need for better characterization of CSC-enriched cultures in the context of their evolution in vitro, in order to uncover their full potential as preclinical models in the studies aimed at identifying molecular biomarkers and developing new therapeutic approaches of human gliomas.Publication Cancer Stem Cells in Soft-Tissue Sarcomas(Multidisciplinary Digital Publishing Institute (MDPI), 2020-06) Martinez-Delgado, Paula; Lacerenza, Serena; Obrador-Hevia, Antonia; Lopez-Alvarez, Maria; Mondaza-Hernandez, Jose L; Blanco-Alcaina, Elena; Sanchez-Bustos, Paloma; Hindi, Nadia; Moura, David S; Martin-Broto, JavierSoft tissue sarcomas (STS) are a rare group of mesenchymal solid tumors with heterogeneous genetic profiles and clinical features. Systemic chemotherapy is the backbone treatment for advanced STS; however, STS frequently acquire resistance to standard therapies, which highlights the need to improve treatments and identify novel therapeutic targets. Increases in the knowledge of the molecular pathways that drive sarcomas have brought to light different molecular alterations that cause tumor initiation and progression. These findings have triggered a breakthrough of targeted therapies that are being assessed in clinical trials. Cancer stem cells (CSCs) exhibit mesenchymal stem cell (MSC) features and represent a subpopulation of tumor cells that play an important role in tumor progression, chemotherapy resistance, recurrence and metastasis. In fact, CSCs phenotypes have been identified in sarcomas, allied to drug resistance and tumorigenesis. Herein, we will review the published evidence of CSCs in STS, discussing the molecular characteristic of CSCs, the commonly used isolation techniques and the new possibilities of targeting CSCs as a way to improve STS treatment and consequently patient outcome.Publication EphrinB2 drives perivascular invasion and proliferation of glioblastoma stem-like cells(eLife Sciences Publications, 2016-06-28) Krusche, Benjamin; Ottone, Cristina; Clements, Melanie P; Johnstone, Ewan R; Goetsch, Katrin; Lieven, Huang; Mota, Silvia G; Singh, Poonam; Khadayate, Sanjay; Ashraf, Azhaar; Davies, Timothy; Pollard, Steven M; De Paola, Vincenzo; Roncaroli, Federico; Martinez Torrecuadrada, Jorge Luis; Bertone, Paul; Parrinello, Simona; Comunidad de Madrid (España); Medical Research Council Cell Interactions and Cancer; Royal Society (Reino Unido)Glioblastomas (GBM) are aggressive and therapy-resistant brain tumours, which contain a subpopulation of tumour-propagating glioblastoma stem-like cells (GSC) thought to drive progression and recurrence. Diffuse invasion of the brain parenchyma, including along preexisting blood vessels, is a leading cause of therapeutic resistance, but the mechanisms remain unclear. Here, we show that ephrin-B2 mediates GSC perivascular invasion. Intravital imaging, coupled with mechanistic studies in murine GBM models and patient-derived GSC, revealed that endothelial ephrin-B2 compartmentalises non-tumourigenic cells. In contrast, upregulation of the same ephrin-B2 ligand in GSC enabled perivascular migration through homotypic forward signalling. Surprisingly, ephrin-B2 reverse signalling also promoted tumourigenesis cell-autonomously, by mediating anchorage-independent cytokinesis via RhoA. In human GSC-derived orthotopic xenografts, EFNB2 knock-down blocked tumour initiation and treatment of established tumours with ephrin-B2-blocking antibodies suppressed progression. Thus, our results indicate that targeting ephrin-B2 may be an effective strategy for the simultaneous inhibition of invasion and proliferation in GBM.Publication Genetically engineered mouse models of pancreatic adenocarcinoma.(Wiley, 2013-04) Guerra, Carmen; Barbacid, Mariano; Unión Europea. Comisión Europea. European Research Council (ERC); EU-Framework Programme; Ministerio de Economía y Competitividad (España)Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of human cancer for which there are no effective therapies. Deep sequencing of PDAC tumors has revealed the presence of a high number of mutations (>50) that affect at least a dozen key signaling pathways. This scenario highlights the urgent need to develop experimental models that faithfully reproduce the natural history of these human tumors in order to understand their biology and to design therapeutic approaches that might effectively interfere with their multiple mutated pathways. Over the last decade, several models, primarily based on the genetic activation of resident KRas oncogenes knocked-in within the endogenous KRas locus have been generated. These models faithfully reproduce the histological lesions that characterize human pancreatic tumors. Decoration of these models with additional mutations, primarily involving tumor suppressor loci known to be also mutated in human PDAC tumors, results in accelerated tumor progression and in the induction of invasive and metastatic malignancies. Mouse PDACs also display a desmoplastic stroma and inflammatory responses that closely resemble those observed in human patients. Interestingly, adult mice appear to be resistant to PDAC development unless the animals undergo pancreatic damage, mainly in the form of acute, chronic or even temporary pancreatitis. In this review, we describe the most representative models available to date and how their detailed characterization is allowing us to understand their cellular origin as well as the events involved in tumor progression. Moreover, their molecular dissection is starting to unveil novel therapeutic strategies that could be translated to the clinic in the very near future.Publication Immune Landscape in Tumor Microenvironment: Implications for Biomarker Development and Immunotherapy(Multidisciplinary Digital Publishing Institute (MDPI), 2020-08) Pérez-Romero, Karim; Rodriguez, Ramon M; Amedei, Amedeo; Barcelo-Coblijn, Gwendolyn; Lopez, Daniel HIntegration of the tumor microenvironment as a fundamental part of the tumorigenic process has undoubtedly revolutionized our understanding of cancer biology. Increasing evidence indicates that neoplastic cells establish a dependency relationship with normal resident cells in the affected tissue and, furthermore, develop the ability to recruit new accessory cells that aid tumor development. In addition to normal stromal and tumor cells, this tumor ecosystem includes an infiltrated immune component that establishes complex interactions that have a critical effect during the natural history of the tumor. The process by which immune cells modulate tumor progression is known as immunoediting, a dynamic process that creates a selective pressure that finally leads to the generation of immune-resistant cells and the inability of the immune system to eradicate the tumor. In this context, the cellular and functional characterization of the immune compartment within the tumor microenvironment will help to understand tumor progression and, ultimately, will serve to create novel prognostic tools and improve patient stratification for cancer treatment. Here we review the impact of the immune system on tumor development, focusing particularly on its clinical implications and the current technologies used to analyze immune cell diversity within the tumor.Publication Inhibition of DYRK1A destabilizes EGFR and reduces EGFR-dependent glioblastoma growth(American Society for Clinical Investigation (ASCI), 2013-06) Pozo, Natividad; Zahonero, Cristina; Fernández, Paloma; Liñares, Jose M; Ayuso, Angel; Hagiwara, Masatoshi; Pérez, Angel; Ricoy, Jose R; Hernández-Laín, Aurelio; Sepúlveda, Juan M; Sánchez-Gómez, Pilar; Ministerio de Ciencia e Innovación (España); Ministerio de Educación y Ciencia (España); Ministerio de Asuntos Exteriores y Cooperación (España); Instituto de Salud Carlos III; Fundación Mutua MadrileñaGlioblastomas (GBMs) are very aggressive tumors that are resistant to conventional chemo- and radiotherapy. New molecular therapeutic strategies are required to effectively eliminate the subpopulation of GBM tumor-initiating cells that are responsible for relapse. Since EGFR is altered in 50% of GBMs, it represents one of the most promising targets; however, EGFR kinase inhibitors have produced poor results in clinical assays, with no clear explanation for the observed resistance. We uncovered a fundamental role for the dual-specificity tyrosine phosphorylation-regulated kinase, DYRK1A, in regulating EGFR in GBMs. We found that DYRK1A was highly expressed in these tumors and that its expression was correlated with that of EGFR. Moreover, DYRK1A inhibition promoted EGFR degradation in primary GBM cell lines and neural progenitor cells, sharply reducing the self-renewal capacity of normal and tumorigenic cells. Most importantly, our data suggest that a subset of GBMs depends on high surface EGFR levels, as DYRK1A inhibition compromised their survival and produced a profound decrease in tumor burden. We propose that the recovery of EGFR stability is a key oncogenic event in a large proportion of gliomas and that pharmacological inhibition of DYRK1A could represent a promising therapeutic intervention for EGFR-dependent GBMs.Publication Inhibition of TRF1 Telomere Protein Impairs Tumor Initiation and Progression in Glioblastoma Mouse Models and Patient-Derived Xenografts.(Cell Press, 2017-11-13) Bejarano, Leire; Schuhmacher, Alberto J; Méndez, Marinela; Megías, Diego; Blanco-Aparicio, Carmen; Martinez, Sonia; Pastor Fernandez, Joaquin; Squatrito, Massimo; Blasco, MA; Fundación Banco Santander; Fundacion Botin; Worldwide Cancer Research; Ministerio de Ciencia e Innovación (España)Glioblastoma multiforme (GBM) is a deadly and common brain tumor. Poor prognosis is linked to high proliferation and cell heterogeneity, including glioma stem cells (GSCs). Telomere genes are frequently mutated. The telomere binding protein TRF1 is essential for telomere protection, and for adult and pluripotent stem cells. Here, we find TRF1 upregulation in mouse and human GBM. Brain-specific Trf1 genetic deletion in GBM mouse models inhibited GBM initiation and progression, increasing survival. Trf1 deletion increased telomeric DNA damage and reduced proliferation and stemness. TRF1 chemical inhibitors mimicked these effects in human GBM cells and also blocked tumor sphere formation and tumor growth in xenografts from patient-derived primary GSCs. Thus, targeting telomeres throughout TRF1 inhibition is an effective therapeutic strategy for GBM.Publication Mesenchymal stromal cells derived from the bone marrow of acute lymphoblastic leukemia patients show altered BMP4 production: correlations with the course of disease.(Public Library of Science (PLOS), 2014) Vicente López, Ángeles; Vázquez García, Miriam Nohemí; Melen, Gustavo J; Entrena Martínez, Ana; Orellana, Manuel Ramírez; González, Agustín Gregorio Zapata; Cubillo, Isabel; Garcia-Castro, Javier; Ministerio de Ciencia e Innovación (España); Asociación Española Contra el Cáncer; Comunidad de Madrid (España); Instituto de Salud Carlos III; Ministerio de Educación, Cultura y Deporte (España)The relevance of tumor microenvironment for the development and progression of tumor cells in hematological malignancies has been extensively reported. Identification of factors involved in the information exchange between the malignant cells and the bone marrow mesenchymal stem cells (BM-MSCs) and the knowledge on their functioning may provide important information to eliminate leukemic cells from protective BM niches. We evaluated changes in BM-MSCs obtained from children with acute lymphoblastic leukemia (ALL) at different times in the course of disease. Whereas ALL-MSCs did not exhibit phenotypic changes compared to BM-derived MSCs isolated from healthy donors, they exhibited increased adipogenic capacity. In addition, the viability of healthy CD34+ hematopoietic progenitors was significantly reduced when co-cultured with ALL-MSCs. ALL-MSCs grow less efficiently, although gradually recover normal growth with treatment. Accordingly, proliferation is particularly low in MSCs obtained at diagnosis and in the first days of treatment (+15 days), recovering to control levels after 35 days of treatment. Correlating these results with bone morphogenetic protein 4 (BMP4) production, a molecule demonstrated to affect MSC biology, we found higher production of BMP4 in ALL-MSCs derived from patients over the course of disease but not in those free of leukemia. However, no significant differences in the expression of different members of the BMP4 signaling pathway were observed. Furthermore, an inverse correlation between high levels of BMP4 production in the cultures and MSC proliferation was found, as observed in MSCs derived from patients at diagnosis that produce high BMP4 levels. In addition, co-culturing ALL-MSC with the REH leukemia cell line, but not CD34+ hematopoietic progenitors, powerfully enhanced BMP4 production, suggesting an intimate crosstalk among ALL-MSCs isolated from BM colonized by ALL cells that presumably also occurs in situ conditions. Our data may support the participation of BMP4 in BM niche, but the mechanism remains to be elucidated.Publication miR-203 drives breast cancer cell differentiation(BioMed Central (BMC), 2023-08-04) Martínez-Illescas, Nuria G; Leal, Silvia; González, Patricia; Graña-Castro, Osvaldo; Muñoz-Oliveira, Juan José; Cortés-Peña, Alfonso; Gómez-Gil, María; Vega, Zaira; Neva, Verónica; Romero, Andrea; Quintela Fandino, Miguel Angel; Ciruelos, Eva; Sanz, Consuelo; Aragón, Sofía; Sotolongo, Leisy; Jiménez, Sara; Caleiras, Eduardo; Mulero, Francisca; Sánchez, Cristina; Malumbres, Marcos; Salazar-Roa, María; Comunidad de Madrid (España); Ministerio de Ciencia, Innovación y Universidades (España); Asociación Española Contra el CáncerA hallmark of many malignant tumors is dedifferentiated (immature) cells bearing slight or no resemblance to the normal cells from which the cancer originated. Tumor dedifferentiated cells exhibit a higher capacity to survive to chemo and radiotherapies and have the ability to incite tumor relapse. Inducing cancer cell differentiation would abolish their self-renewal and invasive capacity and could be combined with the current standard of care, especially in poorly differentiated and aggressive tumors (with worst prognosis). However, differentiation therapy is still in its early stages and the intrinsic complexity of solid tumor heterogeneity demands innovative approaches in order to be efficiently translated into the clinic. We demonstrate here that microRNA 203, a potent driver of differentiation in pluripotent stem cells (ESCs and iPSCs), promotes the differentiation of mammary gland tumor cells. Combining mouse in vivo approaches and both mouse and human-derived tridimensional organoid cultures, we report that miR-203 influences the self-renewal capacity, plasticity and differentiation potential of breast cancer cells and prevents tumor cell growth in vivo. Our work sheds light on differentiation-based antitumor therapies and offers miR-203 as a promising tool for directly confronting the tumor-maintaining and regeneration capability of cancer cells.Publication Ocoxin Modulates Cancer Stem Cells and M2 Macrophage Polarization in Glioblastoma(Hindawi, 2019) Hernandez-Sanmiguel, Esther; Gargini, Ricardo; Cejalvo, Teresa; Segura-Collar, Berta; Nuñez-Hervada, Paula; Hortigüela, Rafael; Sepúlveda-Sánchez, Juan Manuel; Hernández-Laín, Aurelio; Pérez-Núñez, Angel; Sanz, Eduardo; Sánchez-Gómez, Pilar; Asociación Española Contra el Cáncer; Red Temática de Investigación Cooperativa en Cáncer (RTICC) (España); Ministerio de Economía y Competitividad (España)Glioblastoma (GBM) is the most common and devastating primary brain tumor. The presence of cancer stem cells (CSCs) has been linked to their therapy resistance. Molecular and cellular components of the tumor microenvironment also play a fundamental role in the aggressiveness of these tumors. In particular, high levels of hypoxia and reactive oxygen species participate in several aspects of GBM biology. Moreover, GBM contains a large number of macrophages, which normally behave as immunosuppressive tumor-supportive cells. In fact, the presence of both, hypoxia and M2-like macrophages, correlates with malignancy and poor prognosis in gliomas. Antioxidant agents, as nutritional supplements, might have antitumor activity. Ocoxin® oral solution (OOS), in particular, has anti-inflammatory and antioxidant properties, as well as antitumor properties in several neoplasia, without known side effects. Here, we describe how OOS affects stem cell properties in certain GBMs, slowing down their tumor growth. In parallel, OOS has a direct effect on macrophage polarization in vitro and in vivo, inhibiting the protumoral features of M2 macrophages. Therefore, OOS could be a feasible candidate to be used in combination therapies during GBM treatment because it can target the highly resilient CSCs as well as their supportive immune microenvironment, without adding toxicity to conventional treatments.Publication ODZ1 allows glioblastoma to sustain invasiveness through a Myc-dependent transcriptional upregulation of RhoA(Springer, 2016) Talamillo, A; Grande, L; Ruiz-Ontañon, P; Velasquez, C; Mollinedo, P; Torices, S; Sánchez-Gómez, Pilar; Aznar, A; Esparis-Ogando, A; Lopez-Lopez, C; Lafita, C; Berciano, M T; Montero, J A; Vazquez-Barquero, A; Segura, V; Villagra, N T; Pandiella, A; Lafarga, Miguel; Leon, J; Martinez-Climent, J A; Sanz-Moreno, V; Fernandez-Luna, J L; Instituto de Salud Carlos III; Red Temática de Investigación Cooperativa en Cáncer (RTICC) (España); Instituto de Investigación Marqués de Valdecilla; Institute of Cancer Research (Reino Unido); Royal Society (Reino Unido)Long-term survival remains low for most patients with glioblastoma (GBM), which reveals the need for markers of disease outcome and novel therapeutic targets. We describe that ODZ1 (also known as TENM1), a type II transmembrane protein involved in fetal brain development, plays a crucial role in the invasion of GBM cells. Differentiation of glioblastoma stem-like cells drives the nuclear translocation of an intracellular fragment of ODZ1 through proteolytic cleavage by signal peptide peptidase-like 2a. The intracellular fragment of ODZ1 promotes cytoskeletal remodelling of GBM cells and invasion of the surrounding environment both in vitro and in vivo. Absence of ODZ1 by gene deletion or downregulation of ODZ1 by small interfering RNAs drastically reduces the invasive capacity of GBM cells. This activity is mediated by an ODZ1-triggered transcriptional pathway, through the E-box binding Myc protein, that promotes the expression and activation of Ras homolog family member A (RhoA) and subsequent activation of Rho-associated, coiled-coil containing protein kinase (ROCK). Overexpression of ODZ1 in GBM cells reduced survival of xenografted mice. Consistently, analysis of 122 GBM tumour samples revealed that the number of ODZ1-positive cells inversely correlated with overall and progression-free survival. Our findings establish a novel marker of invading GBM cells and consequently a potential marker of disease progression and a therapeutic target in GBM.Publication Premalignant SOX2 overexpression in the fallopian tubes of ovarian cancer patients: Discovery and validation studies(Elsevier, 2016-08-10) Hellner, Karin; Miranda, Fabrizio; Fotso Chedom, Donatien; Herrero-Gonzalez, Sandra; Hayden, Daniel M; Tearle, Rick; Artibani, Mara; KaramiNejadRanjbar, Mohammad; Williams, Ruth; Gaitskell, Kezia; Elorbany, Samar; Xu, Ruoyan; Laios, Alex; Buiga, Petronela; Ahmed, Karim; Dhar, Sunanda; Zhang, Rebecca Yu; Campo, Leticia; Myers, Kevin A; Lozano, María; Ruiz-Miró, María; Gatius, Sónia; Mota, Alba; Moreno-Bueno, Gema; Matias-Guiu, Xavier; Benitez, Javier; Witty, Lorna; McVean, Gil; Leedham, Simon; Tomlinson, Ian; Drmanac, Radoje; Cazier, Jean-Baptiste; Klein, Robert; Dunne, Kevin; Bast, Robert C; Kennedy, Stephen H; Hassan, Bassim; Lise, Stefano; Garcia, María José; Peters, Brock A; Yau, Christopher; Sauka-Spengler, Tatjana; Ahmed, Ahmed Ashour; Ovarian Cancer Action (Reino Unido); NIHR - Oxford Biomedical Research Centre (Reino Unido); National Institute for Health Research (Reino Unido); Experimental Cancer Medicine Centres; Medical Research Council (Reino Unido); Wellcome Trust; Cancer Research UK (Reino Unido)Current screening methods for ovarian cancer can only detect advanced disease. Earlier detection has proved difficult because the molecular precursors involved in the natural history of the disease are unknown. To identify early driver mutations in ovarian cancer cells, we used dense whole genome sequencing of micrometastases and microscopic residual disease collected at three time points over three years from a single patient during treatment for high-grade serous ovarian cancer (HGSOC). The functional and clinical significance of the identified mutations was examined using a combination of population-based whole genome sequencing, targeted deep sequencing, multi-center analysis of protein expression, loss of function experiments in an in-vivo reporter assay and mammalian models, and gain of function experiments in primary cultured fallopian tube epithelial (FTE) cells. We identified frequent mutations involving a 40kb distal repressor region for the key stem cell differentiation gene SOX2. In the apparently normal FTE, the region was also mutated. This was associated with a profound increase in SOX2 expression (p<2(-16)), which was not found in patients without cancer (n=108). Importantly, we show that SOX2 overexpression in FTE is nearly ubiquitous in patients with HGSOCs (n=100), and common in BRCA1-BRCA2 mutation carriers (n=71) who underwent prophylactic salpingo-oophorectomy. We propose that the finding of SOX2 overexpression in FTE could be exploited to develop biomarkers for detecting disease at a premalignant stage, which would reduce mortality from this devastating disease.Publication Pro-Oxidant Activity of Amine-Pyridine-Based Iron Complexes Efficiently Kills Cancer and Cancer Stem-Like Cells(Public Library of Science (PLOS), 2015-09-14) Gonzalez-Bartulos, Marta; Aceves-Luquero, Clara; Qualai, Jamal; Cusso, Olaf; Angeles Martinez, Ma; Fernandez de Mattos, Silvia; Menendez, Javier A; Villalonga, Priam; Costas, Miquel; Ribas, Xavi; Massaguer, AnnaDifferential redox homeostasis in normal and malignant cells suggests that pro-oxidant-induced upregulation of cellular reactive oxygen species (ROS) should selectively target cancer cells without compromising the viability of untransformed cells. Consequently, a pro-oxidant deviation well-tolerated by nonmalignant cells might rapidly reach a cell-death threshold in malignant cells already at a high setpoint of constitutive oxidative stress. To test this hypothesis, we took advantage of a selected number of amine-pyridine-based Fe (II) complexes that operate as efficient and robust oxidation catalysts of organic substrates upon reaction with peroxides. Five of these Fe(II)-complexes and the corresponding aminopyridine ligands were selected to evaluate their anticancer properties. We found that the iron complexes failed to display any relevant activity, while the corresponding ligands exhibited significant antiproliferative activity. Among the ligands, none of which were hemolytic, compounds 1, 2 and 5 were cytotoxic in the low micromolar range against a panel of molecularly diverse human cancer cell lines. Importantly, the cytotoxic activity profile of some compounds remained unaltered in epithelial-to-mesenchymal (EMT)-induced stable populations of cancer stem-like cells, which acquired resistance to the well-known ROS inducer doxorubicin. Compounds 1, 2 and 5 inhibited the clonogenicity of cancer cells and induced apoptotic cell death accompanied by caspase 3/7 activation. Flow cytometry analyses indicated that ligands were strong inducers of oxidative stress, leading to a 7-fold increase in intracellular ROS levels. ROS induction was associated with their ability to bind intracellular iron and generate active coordination complexes inside of cells. In contrast, extracellular complexation of iron inhibited the activity of the ligands. Iron complexes showed a high proficiency to cleave DNA through oxidative-dependent mechanisms, suggesting a likely mechanism of cytotoxicity. In summary, we report that, upon chelation of intracellular iron, the pro-oxidant activity of amine-pyrimidine-based iron complexes efficiently kills cancer and cancer stem-like cells, thus providing functional evidence for an efficient family of redox-directed anti-cancer metallodrugs.Publication Targeting Glioma Initiating Cells with A combined therapy of cannabinoids and temozolomide(Elsevier, 2018) López-Valero, Israel; Saiz-Ladera, Cristina; Torres, Sofía; Hernández-Tiedra, Sonia; García-Taboada, Elena; Rodríguez-Fornés, Fátima; Barba, Marina; Dávila, David; Salvador-Tormo, Nélida; Guzmán, Manuel; Sepúlveda, Juan M; Sánchez-Gómez, Pilar; Lorente, Mar; Velasco, Guillermo; Instituto de Salud Carlos III; Unión Europea. Fondo Europeo de Desarrollo Regional (FEDER/ERDF); Fundación Mutua Madrileña; Ministerio de Economía y Competitividad (España); GW Pharma Ltd. (UK); Comunidad de Madrid (España); Fundación La Marató TV3; Voices Against Brain Cancer (US); The Medical Cannabis Bike Tour Foundation (The Netherlands)Glioblastoma multiforme (GBM) is the most frequent and aggressive type of brain tumor due, at least in part, to its poor response to current anticancer treatments. These features could be explained, at least partially, by the presence within the tumor mass of a small population of cells termed Glioma Initiating Cells (GICs) that has been proposed to be responsible for the relapses occurring in this disease. Thus, the development of novel therapeutic approaches (and specifically those targeting the population of GICs) is urgently needed to improve the survival of the patients suffering this devastating disease. Previous observations by our group and others have shown that Δ9-Tetrahydrocannabinol (THC, the main active ingredient of marijuana) and other cannabinoids including cannabidiol (CBD) exert antitumoral actions in several animal models of cancer, including gliomas. We also found that the administration of THC (or of THC + CBD at a 1:1 ratio) in combination with temozolomide (TMZ), the benchmark agent for the treatment of GBM, synergistically reduces the growth of glioma xenografts. In this work we investigated the effect of the combination of TMZ and THC:CBD mixtures containing different ratios of the two cannabinoids in preclinical glioma models, including those derived from GICs. Our findings show that TMZ + THC:CBD combinations containing a higher proportion of CDB (but not TMZ + CBD alone) produce a similar antitumoral effect as the administration of TMZ together with THC and CBD at a 1:1 ratio in xenografts generated with glioma cell lines. In addition, we also found that the administration of TMZ + THC:CBD at a 1:1 ratio reduced the growth of orthotopic xenografts generated with GICs derived from GBM patients and enhanced the survival of the animals bearing these intracranial xenografts. Remarkably, the antitumoral effect observed in GICs-derived xenografts was stronger when TMZ was administered together with cannabinoid combinations containing a higher proportion of CBD. These findings support the notion that the administration of TMZ together with THC:CBD combinations - and specifically those containing a higher proportion of CBD - may be therapeutically explored to target the population of GICs in GBM.Publication Targeting stromal remodeling and cancer stem cell plasticity overcomes chemoresistance in triple negative breast cancer.(2018-07-24) Cazet, Aurélie S; Hui, Mun N; Elsworth, Benjamin L; Wu, Sunny Z; Roden, Daniel; Chan, Chia-Ling; Skhinas, Joanna N; Collot, Raphaël; Yang, Jessica; Harvey, Kate; Johan, M Zahied; Cooper, Caroline; Nair, Radhika; Herrmann, David; McFarland, Andrea; Deng, Niantao; Ruiz-Borrego, Manuel; Rojo, Federico; Trigo, José M; Bezares, Susana; Caballero, Rosalía; Lim, Elgene; Timpson, Paul; O'Toole, Sandra; Watkins, D Neil; Cox, Thomas R; Samuel, Michael S; Martín, Miguel; Swarbrick, AlexanderThe cellular and molecular basis of stromal cell recruitment, activation and crosstalk in carcinomas is poorly understood, limiting the development of targeted anti-stromal therapies. In mouse models of triple negative breast cancer (TNBC), Hedgehog ligand produced by neoplastic cells reprograms cancer-associated fibroblasts (CAFs) to provide a supportive niche for the acquisition of a chemo-resistant, cancer stem cell (CSC) phenotype via FGF5 expression and production of fibrillar collagen. Stromal treatment of patient-derived xenografts with smoothened inhibitors (SMOi) downregulates CSC markers expression and sensitizes tumors to docetaxel, leading to markedly improved survival and reduced metastatic burden. In the phase I clinical trial EDALINE, 3 of 12 patients with metastatic TNBC derived clinical benefit from combination therapy with the SMOi Sonidegib and docetaxel chemotherapy, with one patient experiencing a complete response. These studies identify Hedgehog signaling to CAFs as a novel mediator of CSC plasticity and an exciting new therapeutic target in TNBC.Publication The Peptidoglycan Recognition Protein 1 confers immune evasive properties on pancreatic cancer stem cells.(BMJ Publishing Group, 2024-08-08) López-Gil, Juan Carlos; García-Silva, Susana; Ruiz-Cañas, Laura; Navarro, Diego; Palencia-Campos, Adrián; Giráldez-Trujillo, Antonio; Earl, Julie; Dorado, Jorge; Gómez-López, Gonzalo; Monfort-Vengut, Ana; Alcalá, Sonia; Gaida, Matthias M; García-Mulero, Sandra; Cabezas-Sáinz, Pablo; Batres-Ramos, Sandra; Barreto, Emma; Sánchez-Tomero, Patricia; Vallespinós, Mireia; Ambler, Leah; Lin, Meng-Lay; Aicher, Alexandra; García García de Paredes, Ana; de la Pinta, Carolina; Sanjuanbenito, Alfonso; Ruz-Caracuel, Ignacio; Rodríguez-Garrote, Mercedes; Guerra, Carmen; Carrato, Alfredo; de Cárcer, Guillermo; Sánchez, Laura; Nombela-Arrieta, César; Espinet, Elisa; Sanchez-Arevalo Lobo, Víctor Javier; Heeschen, Christopher; Sainz, Bruno; Fundación La Caixa; EMBO Scientific Exchange Fellowship; Juan de la Cierva Formacion; Fero Foundation Grant; Ministerio de Economía y Competitividad (España); Asociación Española Contra el Cáncer; Instituto de Salud Carlos III; Unión Europea. Fondo Europeo de Desarrollo Regional (FEDER/ERDF); Centro de Investigación Biomédica en Red - CIBERONC (Cáncer); Xunta de Galicia (España); University of Zurich; German Research Foundation (DFG); Unión Europea. Comisión Europea. European Research Council (ERC); Fondazione AIRC per la ricerca sul cancro; Shanghai Municipal Education Commission (SHMEC); National Natural Science Foundation of China (NSFC)OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) has limited therapeutic options, particularly with immune checkpoint inhibitors. Highly chemoresistant 'stem-like' cells, known as cancer stem cells (CSCs), are implicated in PDAC aggressiveness. Thus, comprehending how this subset of cells evades the immune system is crucial for advancing novel therapies. DESIGN: We used the KPC mouse model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre) and primary tumour cell lines to investigate putative CSC populations. Transcriptomic analyses were conducted to pinpoint new genes involved in immune evasion. Overexpressing and knockout cell lines were established with lentiviral vectors. Subsequent in vitro coculture assays, in vivo mouse and zebrafish tumorigenesis studies, and in silico database approaches were performed. RESULTS: Using the KPC mouse model, we functionally confirmed a population of cells marked by EpCAM, Sca-1 and CD133 as authentic CSCs and investigated their transcriptional profile. Immune evasion signatures/genes, notably the gene peptidoglycan recognition protein 1 (PGLYRP1), were significantly overexpressed in these CSCs. Modulating PGLYRP1 impacted CSC immune evasion, affecting their resistance to macrophage-mediated and T-cell-mediated killing and their tumourigenesis in immunocompetent mice. Mechanistically, tumour necrosis factor alpha (TNF?)-regulated PGLYRP1 expression interferes with the immune tumour microenvironment (TME) landscape, promoting myeloid cell-derived immunosuppression and activated T-cell death. Importantly, these findings were not only replicated in human models, but clinically, secreted PGLYRP1 levels were significantly elevated in patients with PDAC. CONCLUSIONS: This study establishes PGLYRP1 as a novel CSC-associated marker crucial for immune evasion, particularly against macrophage phagocytosis and T-cell killing, presenting it as a promising target for PDAC immunotherapy.Publication Transcriptional regulation of Sox2 by the retinoblastoma family of pocket proteins.(Impact Journals, 2015-02-20) Vilas, Jéssica M; Ferreirós, Alba; Carneiro, Carmen; Morey, Lluis; Da Silva-Álvarez, Sabela; Fernandes, Tânia; Di Croce, Luciano; García-Caballero, Tomás; Rivas, Carmen; Vidal, Anxo; Serrano Marugan, Manuel; Instituto de Salud Carlos III; Xunta de Galicia (España); Ministerio de Economía y Competitividad (España)Cellular reprogramming to iPSCs has uncovered unsuspected links between tumor suppressors and pluripotency factors. Using this system, it was possible to identify tumor suppressor p27 as a repressor of Sox2 during differentiation. This led to the demonstration that defects in the repression of Sox2 can contribute to tumor development. The members of the retinoblastoma family of pocket proteins, pRb, p107 and p130, are negative regulators of the cell cycle with tumor suppressor activity and with roles in differentiation. In this work we studied the relative contribution of the retinoblastoma family members to the regulation of Sox2 expression. We found that deletion of Rb or p130 leads to impaired repression of Sox2, a deffect amplified by inactivation of p53. We also identified binding of pRb and p130 to an enhancer with crucial regulatory activity on Sox2 expression. Using cellular reprogramming we tested the impact of the defective repression of Sox2 and confirmed that Rb deficiency allows the generation of iPSCs in the absence of exogenous Sox2. Finally, partial depletion of Sox2 positive cells reduced the pituitary tumor development initiated by Rb loss in vivo. In summary, our results show that Sox2 repression by pRb is a relevant mechanism of tumor suppression.