Microenvironmental hCAP-18/LL-37 promotes pancreatic ductal adenocarcinoma by activating its cancer stem cell compartment

This is the peer reviewed version of the following article: Microenvironmental hCAP-18/LL-37 promotes pancreatic ductal adenocarcinoma by activating its cancer stem cell compartment. Gut 64.12 (2015): 1921-1935 and which has been published in final form at http://dx.doi.org/10.1136/gutjnl-2014-308935OBJECTIVES: The tumour stroma/microenvironment not only provides structural support for tumour development, but more importantly it provides cues to cancer stem cells (CSCs) that regulate their self-renewal and metastatic potential. This is certainly true for pancreatic ductal adenocarcinomas (PDAC), where tumour-associated fibroblasts, pancreatic stellate cells and immune cells create an abundant paracrine niche for CSCs via microenvironment-secreted factors. Thus understanding the role that tumour stroma cells play in PDAC development and CSC biology is of utmost importance. DESIGN: Microarray analyses, tumour microarray immunohistochemical assays, in vitro co-culture experiments, recombinant protein treatment approaches and in vivo intervention studies were performed to understand the role that the immunomodulatory cationic antimicrobial peptide 18/LL-37 (hCAP-18/LL-37) plays in PDAC biology. RESULTS: We found that hCAP-18/LL-37 was strongly expressed in the stroma of advanced primary and secondary PDAC tumours and is secreted by immune cells of the stroma (eg, tumour-associated macrophages) in response to tumour growth factor-β1 and particularly CSC-secreted Nodal/ActivinA. Treatment of pancreatic CSCs with recombinant LL-37 increased pluripotency-associated gene expression, self-renewal, invasion and tumourigenicity via formyl peptide receptor 2 (FPR2)- and P2X purinoceptor 7 receptor (P2X7R)-dependent mechanisms, which could be reversed by inhibiting these receptors. Importantly, in a genetically engineered mouse model of K-Ras-driven pancreatic tumourigenesis, we also showed that tumour formation was inhibited by either reconstituting these mice with bone marrow from cathelicidin-related antimicrobial peptide (ie, murine homologue of hCAP-18/LL-37) knockout mice or by pharmacologically inhibiting FPR2 and P2X7R. CONCLUSIONS: Thus, hCAP-18/LL-37 represents a previously unrecognised PDAC microenvironment factor that plays a critical role in pancreatic CSC-mediated tumourigenesis.CH: ERC Advanced Investigator Grant (Pa-CSC 233460), European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 256974 (EPC-TM-NET) and n° 602783 (CAM-PaC), the Subdirección General de Evaluación y Fomento de la Investigación, Fondo de Investigación Sanitaria (PS09/02129 & PI12/02643) and the Programa Nacional de Internacionalización de la I+D, Subprogramma: FCCI 2009 (PLE2009-0105; both Ministerio de Economía y Competitividad (es), Spain), BSJr: Rámon y Cajal Merit Award from the Ministerio de Economía y Competitividad, Spain and Clinic and Laboratory Integration Program (CLIP) grant from the Cancer Research Institute, NY, NY. MC: La Caixa Predoctoral Fellowshi

DNMT1 Inhibition Reprograms Pancreatic Cancer Stem Cells via Upregulation of the miR-17-92 Cluster.

Pancreatic ductal adenocarcinoma (PDAC) and other carcinomas are hierarchically organized, with cancer stem cells (CSC) residing at the top of the hierarchy, where they drive tumor progression, metastasis, and chemoresistance. As CSC and non-CSC share an identical genetic background, we hypothesize that differences in epigenetics account for the striking functional differences between these two cell populations. Epigenetic mechanisms, such as DNA methylation, play an important role in maintaining pluripotency and regulating the differentiation of stem cells, but the role of DNA methylation in pancreatic CSC is obscure. In this study, we investigated the genome-wide DNA methylation profile of PDAC CSC, and we determined the importance of DNA methyltransferases for CSC maintenance and tumorigenicity. Using high-throughput methylation analysis, we discovered that sorted CSCs have a higher level of DNA methylation, regardless of the heterogeneity or polyclonality of the CSC populations present in the tumors analyzed. Mechanistically, CSC expressed higher DNMT1 levels than non-CSC. Pharmacologic or genetic targeting of DNMT1 in CSCs reduced their self-renewal and in vivo tumorigenic potential, defining DNMT1 as a candidate CSC therapeutic target. The inhibitory effect we observed was mediated in part through epigenetic reactivation of previously silenced miRNAs, in particular the miR-17-92 cluster. Together, our findings indicate that DNA methylation plays an important role in CSC biology and also provide a rationale to develop epigenetic modulators to target CSC plasticity and improve the poor outcome of PDAC patients. Cancer Res; 76(15); 4546-58. ©2016 AACR

Prevention of Teratogenesis in Pregnancies of Obese Rats by Vitamin E Supplementation

Congenital malformations are a common adverse outcome in pregnancies complicated by pregestational obesity, although the underlying mechanisms are still unrevealed. Our aim was to study the effect of oxidative stress in obesity-induced teratogenesis. Wistar rats were fed a high-fat diet for 13 weeks, with (OE group) or without (O group) vitamin E supplementation. Then, rats were mated and sacrificed at day 11.5 of gestation. Embryos from O dams presented a 25.9 ± 3.5% rate of malformations (vs. 8.7 ± 3.4% in C rats), which was reduced in the OE group (11.5 ± 2.3%). Pregestational obesity induced hepatic protein and DNA oxidation and a decline in antioxidant enzymes. Importantly, glutathione content was also decreased, limiting the availability of this antioxidant in the embryos. Vitamin E supplementation efficiently maintained glutathione levels in the obese mothers, which could be used in their embryos to prevent oxidation-induced malformations. To test the effect of decreasing glutathione levels alone in a cell culture model of neuroepithelium, murine embryonic stem cells (ESC) were induced to form neuronal precursors and glutathione synthesis was inhibited with the gamma–glutamylcysteine synthesis inhibitor, buthionine sulfoximine (BSO). BSO inhibited the expression of Pax3, a gene required for neural tube closure that is also inhibited by oxidative stress. Taken together, our data indicate that obesity causes malformations through the depletion of maternal glutathione, thereby decreasing glutathione-dependent free radical scavenging in embryos, which can be prevented by vitamin E supplementation

Combination of Injectable Multiple Growth Factor-Releasing Scaffolds and Cell Therapy as an Advanced Modality to Enhance Tissue Neovascularization

Objective-Vasculogenic progenitor cell therapy for ischemic diseases bears great potential but still requires further optimization for justifying its clinical application. Here, we investigated the effects of in vivo tissue engineering by combining vasculogenic progenitors with injectable scaffolds releasing controlled amounts of proangiogenic growth factors. Methods and Results-We produced biodegradable, injectable polylactic coglycolic acid-based scaffolds releasing single factors or combinations of vascular endothelial growth factor, hepatocyte growth factor, and angiopoietin-1. Dual and triple combinations of scaffold-released growth factors were superior to single release. In murine hindlimb ischemia models, scaffolds releasing dual (vascular endothelial growth factor and hepatocyte growth factor) or triple combinations improved effects of cord blood-derived vasculogenic progenitors. Increased migration, homing, and incorporation of vasculogenic progenitors into the vasculature augmented capillary density, translating into improved blood perfusion. Most importantly, scaffold-released triple combinations including the vessel stabilizer angiopoietin-1 enhanced the number of perivascular smooth muscle actin(+) vascular smooth muscle cells, indicating more efficient vessel stabilization. Conclusion-Vasculogenic progenitor cell therapy is significantly enhanced by in vivo tissue engineering providing a proangiogenic and provasculogenic growth factor-enriched microenvironment. Therefore, combined use of scaffold-released growth factors and cell therapy improves neovascularization in ischemic diseases and may translate into more pronounced clinical effectsPeer reviewe

L'Âge d'or

Qu’il semble loin, le temps où les études sur l’image au sein de l’hispanisme français étaient une affaire de pionniers marginaux! En 1986, Marcel Oms soutenait la première thèse sur le cinéma espagnol, suivi par quelques autres pionniers. Depuis la seconde moitié des années quatre-vingt-dix, les thèses sur l’image dans le monde ibérique et ibéroaméricain se sont échelonnées, d’abord au compte-gouttes puis de manière beaucoup plus régulière. Parallèlement, durant ces vingt dernières années, les travaux dans le domaine de l’image se sont développés au sein d’un grand nombre de disciplines de l’université française: cinéma, audiovisuel, communication, photographie, peinture, domaines actuellement en plein essor. Par ailleurs, le développement technologique a progressivement facilité l’accès aux sources. En Espagne, au Portugal et en Amérique Latine, il en a été de même. En outre, depuis dix ans, en France, dans le domaine de l’hispanisme, la présence systématique de documents visuels au concours de recrutement des professeurs d’espagnol (CAPES, Agrégation), directement préparé dans des départements d’espagnol, a conduit à l’introduction d’enseignements plus généraux sur l’image dans les cursus universitaires. L’une des originalités de l’hispanisme français, par rapport au domaine de l’image, est liée au fait qu’il se situe à la croisée de divers champs disciplinaires. Les hispanistes, traditionnellement formés à partir de la littérature, de la civilisation et de l’étude de la langue, ont su également puiser aux sources méthodologiques d’autres disciplines (histoire, études cinématographiques, sociologie, anthropologie, etc.), en fonction des sujets de recherche, pour mener des études sur l’image, un domaine ouvert et particulièrement dynamique, un véritable carrefour. L’objectif de la revue L’Âge d’Or: images dans le monde ibérique et ibéroaméricain est de rendre accessible à un large public cette nouvelle donne de la recherche française. La revue prétend être, à son tour, un carrefour, un lieu d’échanges où, non seulement sont publiés les travaux d’hispanistes ou de lusistes, mais aussi de ceux qui, en France comme à l’étranger, partagent le même intérêt pour l’image dans le monde ibérique et ibéroaméricain. Ce premier numéro recueille une série de textes qui, sous le titre «Nouveaux regards, nouveaux territoires», ont fait l’objet de communications dans le cadre des activités d’EMHIS. Nos remerciements à Armelle Jacquet, qui a collaboré à la mise en œuvre de ce premier numéro

Pedobacter lusitanus sp. nov., isolated from sludge of a deactivated uranium mine

Strain NL19(T) is a Gram-stain-negative, aerobic bacterium that was isolated from sludge of a deactivated uranium mine in Portugal. 16S rRNA gene sequence analysis revealed that strain NL19(T) is a member of the genus Pedobacter and closely related to the strains Pedobacter himalayensis MTCC 6384(T), Pedobacter cryoconitis DSM 14825(T), Pedobacter westerhofensis DSM 19036 (T) and Pedobacter hartonius DSM 19033(T). It had a DNA G+C content of 40.8 mol%, which agreed with the genus description. The main fatty acids included C-16 : 1 omega 7c, C-14 : 1 omega 5c, C-4 : 0, iso-C-17 : 0, iso-C-17 : 0 3-OH, C-16 : 0, anteiso-C-15 : 0 and isoC(15 : 0) 3-OH. The main lipids present were phospholipids (60 %) and sphingolipids (35 %). The most abundant phospholipids included phosphatidylethanolamine, phosphatidylinositol and phosphatidylcholine. Menaquinone-7 (MK-7) was the only isoprenoid quinone detected. DNA-DNA hybridization similarities between strain NL19(T) and Pedobacter himalayensis MTCC 6384(T), Pedobacter cryoconitis DSM 14825(T), Pedobacter westerhofensis DSM 19036(T) and Pedobacter hartonius DSM 19033(T) were 15.3, 16.2, 11.5 and 16.0 %, respectively. Strain NL19(T) can also be distinguished from these four species based on gyrB and intergenic transcribed spacers (ITS) sequences and by some phenotypic traits such as NaCl tolerance, pH, growth temperature and carbon source utilization. Strain NL19(T) represents a novel species of the genus Pedobacter, for which the name Pedobacter lusitanus sp. nov. is proposed. The type strain is NL19(T) (= LMG 29220(T) = CECT 9028(T)). An amended description of Pedobacter himalayensis is also included.info:eu-repo/semantics/publishedVersio

Inhibiting NR5A2 targets stemness in pancreatic cancer by disrupting SOX2/MYC signaling and restoring chemosensitivity

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is a profoundly aggressive and fatal cancer. One of the key factors defining its aggressiveness and resilience against chemotherapy is the existence of cancer stem cells (CSCs). The important task of discovering upstream regulators of stemness that are amenable for targeting in PDAC is essential for the advancement of more potent therapeutic approaches. In this study, we sought to elucidate the function of the nuclear receptor subfamily 5, group A, member 2 (NR5A2) in the context of pancreatic CSCs. Methods We modeled human PDAC using primary PDAC cells and CSC-enriched sphere cultures. NR5A2 was genetically silenced or inhibited with Cpd3. Assays included RNA-seq, sphere/colony formation, cell viability/toxicity, real-time PCR, western blot, immunofluorescence, ChIP, CUT&Tag, XF Analysis, lactate production, and in vivo tumorigenicity assays. PDAC models from 18 patients were treated with Cpd3-loaded nanocarriers. Results Our findings demonstrate that NR5A2 plays a dual role in PDAC. In differentiated cancer cells, NR5A2 promotes cell proliferation by inhibiting CDKN1A. On the other hand, in the CSC population, NR5A2 enhances stemness by upregulating SOX2 through direct binding to its promotor/enhancer region. Additionally, NR5A2 suppresses MYC, leading to the activation of the mitochondrial biogenesis factor PPARGC1A and a shift in metabolism towards oxidative phosphorylation, which is a crucial feature of stemness in PDAC. Importantly, our study shows that the specific NR5A2 inhibitor, Cpd3, sensitizes a significant fraction of PDAC models derived from 18 patients to standard chemotherapy. This treatment approach results in durable remissions and long-term survival. Furthermore, we demonstrate that the expression levels of NR5A2/SOX2 can predict the response to treatment. Conclusions The findings of our study highlight the cell context-dependent effects of NR5A2 in PDAC. We have identified a novel pharmacological strategy to modulate SOX2 and MYC levels, which disrupts stemness and prevents relapse in this deadly disease. These insights provide valuable information for the development of targeted therapies for PDAC, offering new hope for improved patient outcomes. Graphical Abstract A Schematic illustration of the role of NR5A2 in cancer stem cells versus differentiated cancer cells, along with the action of the NR5A2 inhibitor Cpd3. B Overall survival of tumor-bearing mice following allocated treatment. A total of 18 PDX models were treated using a 2 x 1 x 1 approach (two animals per model per treatment); n=36 per group (illustration created with biorender.com )

Vascular Dysfunction in Mother and Offspring During Preeclampsia: Contributions from Latin-American Countries

Pregnancy is a physiologically stressful condition that generates a series of functional adaptations by the cardiovascular system. The impact of pregnancy on this system persists from conception beyond birth. Recent evidence suggests that vascular changes associated with pregnancy complications, such as preeclampsia, affect the function of the maternal and offspring vascular systems, after delivery and into adult life. Since the vascular system contributes to systemic homeostasis, defective development or function of blood vessels predisposesboth mother and infant to future risk for chronic disease. These alterations in later life range from fertility problems to alterations in the central nervous system or immune system, among others. It is important to note that rates of morbi-mortality due to pregnancy complications including preeclampsia, as well as cardiovascular diseases have a higher incidence in Latin American countries than in more developed countries. Nonetheless, there is a lack both in the amount and impact of research conducted in Latin America. An impact, althoughsmaller, can be seen when research in vascular disorders related to problems during pregnancy is analyzed. Therefore, in this review, information about preeclampsia and endothelial dysfunction generated from researchgroups based in Latin American countries will be highlighted. We relate the need, as present in many other countries in the world, for increased effective regional and international collaboration to generate new dataspecific to our region on this topic.Fil: Giachini, Fernanda Regina. Universidade Federal de Mato Grosso Do Sul. Centro de Ciencias Biológicas E Da Saude; BrasilFil: Galaviz Hernandez, Carlos. Instituto Politécnico Nacional; MéxicoFil: Damiano, Alicia Ermelinda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Viana, Marta. Universidad CEU San Pablo; EspañaFil: Cadavid, Angela. Universidad de Antioquia; ColombiaFil: Asturizaga, Patricia. Hospital Materno-infantil de la Caja Nacional de Salud; BoliviaFil: Teran, Enrique. Universidad San Francisco de Quito; EcuadorFil: Clapes, Sonia. Universidad de Ciencias Médicas de la Habana; CubaFil: Alcala, Martin. Universidad CEU San Pablo; EspañaFil: Bueno, Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: Calderón Domínguez, María. Universidad CEU San Pablo; EspañaFil: Ramos, María P.. Universidad CEU San Pablo; EspañaFil: Lima, Victor Vitorino. Universidad Federal de Mato Grosso; BrasilFil: Sosa Macias, Martha. Instituto Politécnico Nacional; MéxicoFil: Martinez, Nora Alicia. Universidad de Antioquia; ColombiaFil: Roberts, James M.. University of Pittsburgh; Estados UnidosFil: Escudero, Carlos. Universidad del Bio Bio; Chil