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Human Prostate Carcinoma (human + prostate_carcinoma)
Selected AbstractsPeroxisome proliferator-activated receptor gamma in human prostate carcinomaPATHOLOGY INTERNATIONAL, Issue 5 2009Yasuhiro Nakamura Peroxisome proliferator-activated receptor (PPAR) is a member of the nuclear hormone receptor superfamily of transcription factors. Peroxisome proliferator-activated receptor gamma (PPAR,) plays an important role in the regulation of lipid homeostasis, adipogenesis, insulin resistance, and development of various organs. Agonists of PPAR, have been also reported to inhibit proliferation of prostate carcinoma cells as in other human malignancies, and these synthetic ligands have been used in differentiation-mediated therapy of various human carcinomas associated with high levels of PPAR,. The significance of PPAR, expression, however, was unknown in human prostate carcinoma tissues. The purpose of the present study was therefore to examine the immunolocalization of PPAR, in human prostate cancer tissues (40 cases) and correlate the findings with clinicopathological features of the patients in order to evaluate its possible biological significance. Twenty-nine patients were positive for PPAR, immunoreactivity (73%) and a significant inverse correlation was detected between PPAR, immunoreactivity, pT stage (P = 0.036), and serum concentration of prostate-specific antigen (P = 0.0004). In conclusion, PPAR, immunoreactivity is considered to be a new clinicopathological parameter of human prostate cancer. [source] Overexpression of cyclooxygenase-2 in human prostate carcinoma and prostatic intraepithelial neoplasia-association with increased expression of polo-like kinase-1THE PROSTATE, Issue 4 2007Carsten Denkert Abstract BACKGROUND Cyclooxygenases (COX) as well as Polo-like kinases (PLK) are involved in proliferation and cell cycle regulation and have been suggested for preventive and therapeutic approaches in prostate carcinoma. METHODS In this study, we studied expression and prognostic impact of COX-2 in invasive prostate carcinoma, prostatic intraepithelial neoplasia (PIN), atrophic glands, and normal prostatic glands, and investigated the association between COX-2 and PLK-1. RESULTS We observed a positivity for COX-2 in 72.1% of PIN and in 44.7% of prostate carcinomas with an overexpression of COX-2 in prostate cancer and PIN compared to benign prostatic tissue (P,<,0.0005). Furthermore, we observed a strong correlation between expression of PLK-1 and COX-2 (P,<,0.0005). CONCLUSIONS To our knowledge, this is the first report of a correlation between COX-2 and PLK-1 in a malignant tumor. COX-2 and PLK-1 may be interesting targets for new molecular therapies in prostate cancer. Prostate 67: 361,369, 2007. © 2007 Wiley-Liss, Inc. [source] Nitroxide tempo, a small molecule, induces apoptosis in prostate carcinoma cells and suppresses tumor growth in athymic miceCANCER, Issue 6 2005Simeng Suy Ph.D. Abstract BACKGROUND In previous studies, nitroxide tempo (2, 2, 6, 6-tetramethyl-piperidine-1-oxyl), a small molecule, induced cell death in cancer cells. The current study examined the antineoplastic properties of tempo in the human hormone-dependent/hormone-independent prostate carcinoma models (LNCaP, DU-145, and PC-3). METHODS The apoptotic effects of tempo were examined by the flow cytometric analysis of cells labeled with fluorescein isothiocyanate-conjugated annexin-V, and by electron microscopy. Enzymatic assays were performed to measure the activities of 2 cysteine proteases, i.e., caspase-9 and caspase-3, in tempo-treated cells. The effects of tempo on cell proliferation and on cell cycle distribution profiles were measured by the flow cytometric assay using immunofluorescent staining of incorporated 5'-bromo-2'-deoxyuridine (BrdU) coupled with 7-amino-actinomycin D (7-AAD) staining of total DNA. The number of proliferating cells was also determined independently by enzyme-linked immunosorbent assay using chemiluminescent detection of incorporated BrdU. Subcutaneous growth of human prostate carcinoma in athymic mice was monitored after intratumoral administration of tempo into tumor-bearing mice. In addition, cell viability assays were performed to compare the cytotoxic effect of a combination of doxorubicin or mitoxantrone and tempo with single agents. RESULTS Tempo treatment of prostate carcinoma cells caused a significant increase in the number of apoptotic cells compared with control groups (tempo, 2.5 mM, 24 hours: DU-145, approximately 3.4-fold; PC-3, approximately 6,7-fold; tempo 1 mM, 24 hours: LNCaP, approximately 12-fold). Tempo-induced loss of cell viability was blocked partially or completely after pretreatment of cells with actinomycin-D or cycloheximide, suggesting a de novo macromolecule synthesis-dependent mechanism of cell death. Electron microscopy revealed aggregation and marginalization of chromatin in the nuclei of a large number of tempo-treated LNCaP cells. Tempo treatment of LNCaP cells resulted in enhanced activities of caspase-9 (tempo, 5 mM, 15 hours: approximately 2-fold) and caspase-3 (tempo, 2.5 mM, 24 hours: approximately 12-fold). Tempo treatment also led to an enhanced number of cells in G2/M phase of the cell cycle (tempo, 5.0 mM, 24 hours: DU-145, approximately 1.6-fold; PC-3, approximately 1.5-fold; LNCaP, approximately 5.3-fold), and decreased BrdU incorporation indicative of a decline in the number of proliferating cells (tempo, 2.5 mM, 24 or 48 hours; DU-145, approximately 2,3-fold; PC-3, approximately 1.2-fold; LNCaP, approximately 5,10-fold). Administration of tempo into LNCaP tumor-bearing mice resulted in a significant inhibition of tumor growth (percent initial tumor volume [Day 30, n = 4]: vehicle, 845.35 ± 272.83; tempo, 9.72 ± 9.72; tempo vs. vehicle, P < 0.02). In hormone-refractory prostate carcinoma cells, a combination of relatively low doses of tempo and doxorubicin or mitoxantrone caused enhanced cytotoxicity as compared with single agents. CONCLUSIONS These data demonstrated that nitroxide tempo induced apoptosis and activated a caspase-mediated signaling pathway in prostate carcinoma cells. Tempo treatment also caused cell cycle arrest in G2/M phase and decreased the number of proliferating cells (S phase). Tempo treatment of tumor-bearing mice led to inhibition of tumor growth, suggesting that tempo is a novel member of the small-molecule family of antineoplastic agents. Cancer 2005. © 2005 American Cancer Society. [source] Mutational analysis of caspase genes in prostate carcinomasAPMIS, Issue 4 2010MIN SUNG KIM Kim MS, Park SW, Kim YR, Lee JY, Lim HW, Song SY, Yoo NJ, Lee SH. Mutational analysis of caspase genes in prostate carcinomas. APMIS 2010; 118: 308,12. Evasion of apoptosis is one of the hallmarks of cancer. Of the components of apoptosis machinery, caspases are the main executioners of apoptosis that initiate and propagate the apoptosis, and finally degrade target molecules. Caspase-encoding genes have been reported to harbor inactivating mutations in many human cancers. However, mutational status of caspase genes in prostate carcinomas has not been identified. The aim of this study was to explore whether caspase genes are somatically mutated in prostate carcinomas. For this, we analyzed entire coding regions of 11 human caspase-encoding genes (CASP1,10 and 14) in 45 prostate carcinoma tissues by a single-strand conformation polymorphism (SSCP) assay. In this study, however, we detected no somatic mutation of CASP genes in the prostate carcinomas by the SSCP. This is the first report on systematic evaluation of caspase-encoding gene mutations in human prostate carcinomas, and our data indicate that CASP genes may not be mutated in prostate carcinomas. The data suggest that apoptosis evasion in prostate carcinoma may be dependent on other mechanisms besides genetic alteration of caspase-encoding genes. [source] | ||||||||||