41 research outputs found

    Glucocorticoid receptor changes its cellular location with breast cancer development.

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    Glucocorticoids play a major role in attenuation of the inflammatory response and they are useful in the primary combination chemotherapy of breast cancer, since in vitro studies have demonstrated an antiproliferative effect in human breast cancer cells. In contrast, it was recently shown that glucocorticoids protect against apoptotic signals evoked by cytokines, cAMP, tumour suppressors, and death genes in mammary gland epithelia. Their actions are mediated by intracellular receptor (GR) that functions as a hormone-dependent transcription factor; however, no previous studies have been focused on GR expression in different pathologies of the human breast, and the possible relationship with that of mineralocorticoid receptor (MR) and COX-2. Also, the role of these proteins on tumoral breast epithelial cells remains unclear. Therefore, we examined GR, MR and COX-2 expression by immunohistochemistry and Western blot techniques in 142 samples of human breast obtained by total or partial mastectomy. We found that the percentage of positive patients presenting nuclear immunoreaction to GR decreased with tumor development, while all samples analyzed showed cytoplasmic immunoreactions to MR. All positive samples to COX-2 antibody showed cytoplasmic location, a higher immunoreaction being observed in benign breast diseases than in carcinomatous lesions. Thus, breast cancer progression is associated with the accumulation of GR in the cytoplasm of tumoral cells and the decrease of COX-2 expression

    Lectin histochemistry study in the human vas deferens

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    The oligosaccharide sequences of glycoconjugates in the normal human vas deferens and the nature of the saccharide linkage were studied by lectin histochem. The cytoplasm of all epithelial cell types (principal cells, basal cells, and mitochondria-rich cells) and luminal contents reacted pos. with WGA, MAA, PNA, DSA, LTA, UEA-I, AAA, and ConA. The reaction was more intense in the stereocilia of principal cells. Cytoplasmic staining was diffuse except for PNA and DSA labeling which was limited to the apical cytoplasm and stereocilia of columnar cells. The cytoplasm of all cell types also reacted diffusely with HPA, although staining was weak and was not obsd. in the stereocilia. Pos. reaction with SBA only was encountered in the stereocilia of principal cells. SNA, LTA, and DBA were unreactive. GNA-labeling showed a granular distribution in the supranuclear cytoplasm of columnar epithelial cells. Reactions with MAA, PNA, DSA, AAA, HPA and SBA disappeared after the β-elimination reaction. Reactions with WGA and UEA-I decreased after ß-elimination or Endo-F digestion. Reactions with ConA and GNA were suppressed by Endo-F digestion. Reactions with PNA, HPA, and SBA increased after desialylation. Of all the lectins that label the luminal contents of the vas deferens, only UEA-I was not found in the luminal contents of seminiferous tubules and epididymis and, thus, this lectin would probably bind to glycoproteins secreted by the vas deferens. The chem. treatments used suggest that this secretion contains fucose residues located in both N- and O-linked oligosaccharides. The other lectins may label secreted proteins, but also structural proteins or proteins reabsorbed from the luminal fluid. The lectin-binding pattern of mitochondria-rich cells in the vas deferens differed from that found in the epididymis

    Anatomía comparada del aparato urinario de mamíferos domésticos. Herramienta de aprendizaje virtual para veterinarios, biólogos y médicos.

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    Esta aplicación es una herramienta útil para estudiantes, profesores y profesionales de diferentes campos. Permitirá conocer y estudiar el aparato urinario, señalando gráficamente la estructura a memorizar, ver su contenido teórico y autoevaluarse

    Anti-proliferative and pro-apoptotic effects of GHRH antagonists in prostate cancer

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    Growth hormone-releasing hormone (GHRH) and its receptors have been implicated in the progression of various tumors. In vitro and in vivo studies have demonstrated that GHRH antagonists inhibit the growth of several cancers. GHRH antagonists, JMR-132 and JV-1-38 inhibit the growth of androgen-independent prostate tumors. Here we investigated the involvement of GHRH antagonists in proliferative and apoptotic processes. We used non-tumoral RWPE-1 and tumoral LNCaP and PC3 human prostatic epithelial cells, as well as an experimental model of human tumor PC3 cells. We evaluated the effects of JMR-132 and JV-1-38 antagonists on cell viability and proliferation in the three cell lines by means of MTT and BrdU assays, respectively, as well as on cell cycle and apoptotic process in PC3 cells. The expression levels of PCNA, p53, p21, CD44, Cyclin D1, c-myc, Bax and Bcl2 were determined in both in vivo and in vitro models by means of Western-blot and RT-PCR. GHRH antagonists suppressed cell proliferation and decreased the levels of the proliferation marker, PCNA, in the three cell lines and in PC3 tumor. GHRH antagonists led to an increase of cells in S-phase and a decrease in G1 and G2/M phases, and induced S-phase arrest and increase of apoptotic cells. The effects of GHRH-antagonists on cell cycle could be due to the changes observed in the expression of p21, p53, Bax, Bcl2, CD44, Cyclin D1, c-myc and caspase 3. Present results confirm and extend the role of GHRH antagonists as anti-proliferative and pro-apoptotic molecules in prostate cancer.Junta de Comunidades de Castilla-La Manch

    Antitumoral effects of vasoactive intestinal peptide in human renal cell carcinoma xenografts in athymic nude mice

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    We studied antitumor effect of VIP in human renal cell carcinoma (RCC) (A498 cells xenografted in immunosuppressed mice). VIP-treated cells gave resulted in p53 upregulation and decreased nuclear ?-catenin translocation and NFKB expression, MMP-2 and MMP-9 activities, VEGF levels and CD-34 expression. VIP led to a more differentiated tubular organization in tumours and less metastatic areas. Thus, VIP inhibits growth of A498-cell tumours acting on the major issues involved in RCC progression such as cell proliferation, microenvironment remodelling, tumour invasion, angiogenesis and metastatic ability. These antitumoral effects of VIP offer new therapeutical possibilities in RCC treatment.Ministerio de Ciencia e InnovaciónJunta de Comunidades de Castilla-La ManchaFundación Mutua MadrileñaFundación Jesús Serra (Grupo Catalana de Occidente

    Human pregnane X receptor is expressed in breast carcinomas, potential heterodimers formation between hPXR and RXR-alpha.

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    The human pregnane X receptor (hPXR) is an orphan nuclear receptor that induces transcription of response elements present in steroid-inducible cytochrome P 450 gene promoters. This activation requires the participation of retinoid X receptors (RXRs), needed partners of hPXR to form heterodimers. We have investigated the expression of hPXR and RXRs in normal, premalignant, and malignant breast tissues, in order to det. whether their expression profile in localized infiltrative breast cancer is assocd. with an increased risk of recurrent disease. Methods: Breast samples from 99 patients including benign breast diseases, in situ and infiltrative carcinomas were processed for immunohistochem. and Western-blot anal. Results: Cancer cells from patients that developed recurrent disease showed a high cytoplasmic location of both hPXR isoforms. Only the infiltrative carcinomas that relapsed before 48 mo showed nuclear location of hPXR isoform 2. This location was assocd. with the nuclear immunoexpression of RXR-alpha. Conclusion: Breast cancer cells can express both variants 1 and 2 of hPXR. Infiltrative carcinomas that recurred showed a nuclear location of both hPXR and RXR-alpha; therefore, the overexpression and the subcellular location changes of hPXR could be considered as a potential new prognostic indicator

    Bisphenol-A Induces Podocytopathy With Proteinuria in Mice

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    Bisphenol-A, a chemical used in the production of the plastic lining of food and beverage containers, can be found in significant levels in human fluids. Recently, bisphenol-A has been associated with low-grade albuminuria in adults as well as in children. Since glomerular epithelial cells (podocytes) are commonly affected in proteinuric conditions, herein we explored the effects of bisphenol-A on podocytes in vitro and in vivo. On cultured podocytes we first observed that bisphenol-A?at low or high concentrations?(10?nM and 100?nM, respectively) was able to induce hypertrophy, diminish viability, and promote apoptosis. We also found an increase in the protein expression of TGF-?1 and its receptor, the cyclin-dependent kinase inhibitor p27Kip1, as well as collagen-IV, while observing a diminished expression of the slit diaphragm proteins nephrin and podocin. Furthermore, mice intraperitoneally injected with bisphenol-A (50?mg/Kg for 5 weeks) displayed an increase in urinary albumin excretion and endogenous creatinine clearance. Renal histology showed mesangial expansion. At ultrastructural level, podocytes displayed an enlargement of both cytoplasm and foot processes as well as the presence of condensed chromatin, suggesting apoptosis. Furthermore, immunohistochemistry for WT-1 (specific podocyte marker) and the TUNEL technique showed podocytopenia as well as the presence of apoptosis, respectively. In conclusion, our data demonstrate that Bisphenol-A exposure promotes a podocytopathy with proteinuria, glomerular hyperfiltration and podocytopenia. Further studies are needed to clarify the potential role of bisphenol-A in the pathogenesis as well as in the progression of renal diseases.Ministerio de Ciencia e InnovaciónInstituto de Salud Carlos IIIThe Eugenio Rodríguez Pascual Foundatio

    Induction of more aggressive tumoral phenotypes in LNCaP and PC3 cells by serum exosomes from prostate cancer patients

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    Prostate cancer (PCa) is the second most frequent and sixth most fatal cancer in men worldwide. Despite its high prevalence, our understanding of its etiology and the molecular mechanisms involved in the progression of the disease is substantially limited. In recent years, the potential participation of exosomes in this process has been suggested. Therefore, we aim to study the effect of exosomes isolated from the serum of patients with PCa on various cellular processes associated with increased tumor aggressiveness in two PCa cell lines: LNCaP-FGC and PC3. The exosomes were isolated by filtration wand ultracentrifugation. Their presence was confirmed by immunodetection of specific markers and their size distribution was analyzed by Dynamic Light Scattering (DLS). The results obtained demonstrated that serum exosomes from PCa patients increased migration of PC3 cells and neuroendocrine differentiation of LNCaP-FGC cells regardless of the grade of the tumor. PCa serum exosomes also enhanced the secretion of enzymes related to invasiveness and resistance to chemotherapeutics, such as extracellular matrix metalloproteases 2 and 9, and gamma-glutamyltransferase in both cell lines. Altogether, these findings support the pivotal participation of exosomes released by tumoral cells in the progression of PCa. Future studies on the molecular mechanisms involved in the observed changes could provide crucial information on this disease and help in the discovery of new therapeutic targets.Instituto de Salud Carlos III (ISCIII) P118/00526, co-funded by European Regional Development Fund (ERDF), A way to make Europe to AM

    Inhibitory Effects of Antagonists of Growth Hormone-Releasing Hormone (GHRH) on Growth and Invasiveness of PC3 Human Prostate Cancer

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    New approaches are needed to the therapy of advanced prostate cancer. This study determined the effect of growth hormone- releasing hormone (GHRH) antagonists, JMR-132 and JV-1-38 on growth of PC3 tumors as well as on angiogenesis and metastasis through the evaluation of various factors that contribute largely to the progression of prostate cancer. Human PC3 androgen-independent prostate cancer cells were injected subcutaneously into nude mice. The treatment with JMR-132 (10 ug/day) or JV-1-38 (20 ug/day) lasted 41 days. We also evaluated the effects of JMR-132 and JV-1-38 on proliferation, cell adhesion and migration in PC-3 cells in vitro. Several techniques (Western blot, reverse transcription polymerase chain reaction, immunohistochemistry, ELISA and zymography) were used to evaluate the expression levels of GHRH receptors and its splice variants, GHRH, vascular endothelial growth factor (VEGF), hypoxia inducible factor (HIF)-1alpha, metalloproteinases (MMPs)-2 and -9, beta-catenin and E-cadherin. GHRH antagonists suppressed the proliferation of PC-3 cells in vitro and significantly inhibited growth of PC3 tumors. After treatment with these analogues, we found an increase in expression of GHRH receptor accompanied by a decrease of GHRH levels, a reduction in both VEGF and HIF-1alpha expression and in active forms of MMP-2 and MMP-9, a significant increase in levels of membrane-associated ?-catenin and a significant decline in E-cadherin. These results support that the blockade of GHRH receptors can modulate elements involved in angiogenesis and metastasis. Consequently, GHRH antagonists could be considered as suitable candidates for therapeutic trials in the management of androgen-independent prostate cancer.Junta de Comunidades de Castilla-La ManchaComunidad de MadridUniversidad de AlcaláMinisterio de Ciencia e Innovacio
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