Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of the JCA-1 prostate cells with different concentrations of microtubule inhibitors-taxol (paclitaxel) vinblastine, and estramustine-was accompanied by reduced cell growth and, correspondingly, characteristic morphological changes. The reduction of cellular proliferation was unlikely to be attributable to an inhibitory effect of the antimicrotubule agents on cell cycling, but was correlated with the decreased expression of the p53 gene. These results suggest that antimicrotubule agents may be considered as potentially complementary treatment modalities for patients with hormonally independent prostate cancer.
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PMID:Effects of microtubule inhibitors-taxol, vinblastine and estramustine on the growth and p53 gene expression in the hormone independent human prostatic JCA-1 cells. 904 36

This paper reviews the current advances in molecular genetics and biology of prostate cancer development. Many genetic alterations in prostate cancer have been identified. Some of these changes are early events and occur in prostatic intraepithelial neoplasia and primary cancer of prostate, some others occur in late stages of prostate cancer development. The significant genetic changes for prostate cancer include losses for chromosomes 8p, 5q, 13q, and so forth; gains for chromosomes 8q, 11p, 3q, and so forth; aneusomies of chromosomes 7 and 8; and allelic losses at chromosome regions 8p 12-21, 10q23-24, 16q22.1-24, and 7q31.1-31.2. The alteration of the p53 tumor-suppressor gene plays a role in a subset of advanced prostate cancer. Expressions of TGF-beta receptors, E-cadherin, C-CAM, KAI1, and some integrins have an inverse correlation with either prostatic carcinogenesis or progression of prostate cancer, or both. Protein expression of BCL-2 in prostate cancer is highly correlated with cancer progression and androgen-independent phenotype. More studies need to be performed to identify specific genes for those genetic alterations and to explore the clinical use of the known molecules in prostate cancer.
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PMID:Molecular advances in prostate cancer. 909 May 1

Insulin-like growth factor (IGF) binding protein-3 (IGFBP-3) is known to block IGF action and inhibit cell growth. IGFBP-3 is thought to act by sequestering free IGFs or, possibly, act via a novel IGF-independent mechanism. Supporting its role as a primary growth inhibitor, IGFBP-3 production has been shown to be increased by cell growth-inhibitory agents, such as transforming growth factor-beta (TGF-beta), and the tumor suppressor gene p53. In this paper, we demonstrate, for the first time, a novel function of IGFBP-3 as an apoptosis-inducing agent and show that this action is mediated through an IGF.IGF receptor-independent pathway. In the p53 negative prostate cancer cell line, PC-3, the addition of recombinant IGFBP-3 resulted in a dose-dependent induction of apoptosis. 125I-IGFBP-3 bound with high affinity to specific proteins in PC-3 cell lysates and plasma membrane preparations. These membrane-associated molecules may serve as receptors that mediate the direct effect of IGFBP-3 on apoptosis. In addition, in an IGF receptor-negative mouse fibroblast cell line, treatment with recombinant IGFBP-3 as well as transfection of the IGFBP-3 gene induced apoptosis, suggesting that neither IGFs nor IGF receptors are required for this action. Furthermore, treatment with TGF-beta1, a known apoptosis-inducing agent, resulted in the induction of IGFBP-3 expression 6-12 h before the onset of apoptosis. This effect of TGF-beta1 was prevented by co-treatment with IGFBP-3-neutralizing antibodies or IGFBP-3-specific antisense thiolated oligonucleotides. These findings suggest that IGFBP-3 induces apoptosis through a novel pathway independent of either p53 or the IGF.IGF receptor-mediated cell survival pathway and that IGFBP-3 mediates TGF-beta1 induced apoptosis in PC-3 cells.
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PMID:Insulin-like growth factor (IGF)-binding protein-3 induces apoptosis and mediates the effects of transforming growth factor-beta1 on programmed cell death through a p53- and IGF-independent mechanism. 911 91

Prostate cancer, like other types of cancer, is associated with the loss of cell cycle control, resulting in unregulated growth of cells. We report here on the inhibitory effects of interferon alpha (IFN alpha) on the cell cycle of prostate cancer cells, using the human prostate carcinoma cell line DU145 that has mutations in the tumor suppressor genes pRB, p53 and KAI1. IFN alpha inhibited growth and colony formation of DU145 cells and analysis by flow cytometry suggests that IFN alpha inhibited the progression of these cancer cells from the G1 through S phase of the cell cycle. IFN alpha treatment of DU145 cells reduced cyclin dependent kinase 2 (cdk2) activity. In particular, cyclin E dependent cdk2 activity was inhibited by IFN alpha treatment. IFN alpha treatment, however, did not affect the amount of cdk2 bound to cyclin E. Consistent with this data, IFN alpha was able to induce expression of the kinase inhibitor p21 in DU145 cells. Furthermore, IFN treatment increased the amounts of p21 complexed with cdk2 in these cells. These data support a role for p21 in mediating the antiproliferative action of IFN alpha. The induction of p21 and its growth inhibitory effects in DU145 cells appears independent of p53, pRB and KAI1 status.
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PMID:IFNalpha induces the expression of the cyclin-dependent kinase inhibitor p21 in human prostate cancer cells. 912 65

We have previously described potent growth-inhibitory effect of a recombinant adenovirus expressing wild type p53 (AdWTp53) in metastatic prostate cancer cells via activation of cellular p53 pathways. We have extended these observations to analyze the effects of AdWTp53 on primary cultures of radical prostatectomy specimens (RPS) and have also evaluated the gene therapeutic potential of the AdWTp53 in a nude mice model. Infection of primary cultures of prostate cancer specimens resulted in about 80% cell growth inhibition in comparison with cultures treated with control adenovirus dl312. Single injection of AdWTp53 into pre-established tumor nodules of DU145 prostate cancer cells suppressed tumor growth significantly (p = 0.0407) as determined by comparison of tumor volumes of the AdWTp53-treated vs. control vector (dl312) or PBS-treated groups. Moreover, there was no significant difference in tumor growth inhibition between single vs. multiple injections of AdWTp53. Our observations support the potential of AdWTp53 for gene therapy of prostate cancer.
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PMID:Inhibition of the growth of pre-established subcutaneous tumor nodules of human prostate cancer cells by single injection of the recombinant adenovirus p53 expression vector. 913 72

Prostate tumor initiation and progression to malignancy may involve upregulation of the androgen receptor known to stimulate prostate cell proliferation; other etiologic mechanisms may include dysfunction of the apoptotic pathway but also deregulation in signal transduction and control of the cell cycle in prostate tissue; such abnormalities could arise from overexpression or mutations in a number of oncogenes or down-regulation by inactivating mutations, allelic loss, or other epigenetic mechanisms in tumor suppressor genes. The advantages and drawbacks of various delivery systems (retroviral, adenoviral, liposomes) used for human gene therapy are being considered. Several ex vivo and in vivo as well as cell culture studies are suggested for the therapy of the human prostate cancer using transfer and expression of genes that might be implicated in prostate carcinogenesis especially of the tumor suppressor p53. Expression of suicidal genes in prostate cancer cells using prostate-specific promoter and enhancer elements as well as targeting of the androgen receptor or the insulin-like growth factor genes with triplex technology in prostate cancer cells and their metastases, is expected to be of therapeutic value.
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PMID:Gene therapy of prostate cancer: p53, suicidal genes, and other targets. 917 86

Prostate cancer and benign tumors of the prostate are the two most common neoplastic diseases in men in the United States, however, research on their causes and treatment has been slow because of the difficulty in obtaining fresh samples of human tissue and a lack of well characterized cell lines which exhibit growth and differentiation characteristics of normal prostatic epithelium. Non-neoplastic adult human prostatic epithelial cells from a white male donor were immortalized with human papillomavirus 18 which resulted in the establishment of the RWPE-1 cell line. Cells from the RWPE-1 cell line were further transformed by v-Ki-ras to establish the RWPE-2 cell line. The objectives of this study were to: (1) establish the prostatic epithelial origin and androgen responsiveness of RWPE-1 and RWPE-2 cell lines; (2) examine their response to growth factors; and (3) establish the malignant characteristics of the RWPE-2 cell line. Immunoperoxidase staining showed that both RWPE-1 and RWPE-2 cells express cytokeratins 8 and 18, which are characteristic of luminal prostatic epithelial cells, but they also coexpress basal cell cytokeratins. These cell lines show growth stimulation and prostate specific antigen (PSA) and androgen receptor (AR) expression in response to the synthetic androgen mibolerone, which establishes their prostatic epithelial origin. Both cell lines also show a dose-dependent growth stimulation by EGF and bFGF and growth inhibition when exposed to TGF-beta, however, the transformed RWPE-2 cells are less responsive. RWPE-1 cells neither grow in agar nor form tumors when injected into nude mice with or without Matrigel. However, RWPE-2 cells form colonies in agar and tumors in nude mice. In the in vitro invasion assay, RWPE-1 cells are not invasive whereas RWPE-2 cells are invasive. Nuclear expression of p53 and Rb proteins was heterogeneous but detectable by immunostaining in both cell lines. The RWPE-1 cells, which show many normal cell characteristics, and the malignant RWPE-2 cells, provide useful cell culture models for studies on prostate growth regulation and carcinogenesis.
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PMID:Androgen responsive adult human prostatic epithelial cell lines immortalized by human papillomavirus 18. 921 5

Mutations of the p53 gene are related to development of human cancers and their frequencies and spectra, the latter representing fingerprints left by carcinogens, provide information about the molecular epidemiology of the disease. Prostate cancer is the most common neoplasm in American males and although its incidence is still relatively low in Japanese people, it has recently been increasing with the westernization of life style. To assess the frequency and spectrum of p53 gene mutations in Japanese prostate cancers, we examined a series of 90 lesions using polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) analysis. The patients' mean age was 69.3 years (range 57-87). Of the total, six were well-, 34 moderately- and 50 poorly-differentiated adenocarcinomas, and the median Gleason score was 7.9. Eleven of the 90 cases (12%) had mutations in exons 2-11 of the p53 gene: none of the five clinical-stage A, one of 25 stage B (4%), three of 35 stage C (9%) and seven of 25 stage D (28%) cancers. The correlation with an advanced stage was statistically significant. One insertion and 10 base pair substitutions were encountered, comprising six transversions (55%) and four transitions (36%). Two of the latter involved methylated cytosine-guanine (CpG). These 11 mutations were combined with 18 other mutations in previous reports concerning Japanese prostate cancers to facilitate comparison of the p53 gene mutational spectrum with those reported for American and European prostate cancers. In the latter, 61% were transitions and 33% were transversions. The greater proportion of transversions in the Japanese population suggests that there are different factors responsible for carcinogenesis of the prostate glands in the various countries.
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PMID:Differences in the p53 gene mutational spectra of prostate cancers between Japan and Western countries. 923 Feb 79

The clinical course of prostate cancer (PCa), the most common cancer in Swedish men, is highly variable and difficult to predict. Consequently, there is an urgent need to distinguish tumours with a high risk of progression from those with a low risk. To investigate the prognostic implications of proliferation and apoptosis, two important processes in tumor biology, immunoreactivity for biomarkers associated with these processes was assessed, quantified in indexes, and related to cause-specific survival (CSS). A consecutive series of 186 men presenting with voiding symptoms and PCa were treated with transurethral resection and deferred endocrine therapy. After 13-21 years follow-up, 43% of these men had died of prostate cancer. In a subgroup of men with localised disease at the time of diagnosis, 27% succumbed to the disease. Immunoreactivity for p53 protein, indicative of a defective p53 function, predicted shorter CSS in univariate (52 vs 123 months, p < 0.0001), but not in multivariate analysis. Mean index for the apoptosis blocking bcl-2 protein was higher in foci of prostatic intraepithelial neoplasia, a putative precursor to PCa, than in manifest cancer areas (79 vs 12, p < 0.0001). This indicates that bcl-2 may be involved in early tumourigenesis. No prognostic value was found for the bcl-2 index. A high index for the proliferation marker Ki-67 predicted shorter CSS in univariate (53 vs 132 months p < 0.0001) and in multivariate analysis. To test if p53 is predictive for clinical radioresistance, as suggested by experimental models, p53 immunoreactivity was investigated in biopsies obtained before radical radiotherapy in an unrelated series of 60 PCa patients. Patients with p53 reactive tumours had longer CSS, indicating that p53 is not treatment-predictive for radiotherapy in Pca. Core biopsies were obtained before and a week after castration therapy in patients with advanced PCa. According to the serum prostate specific antigen (PSA) level 3 months after therapy, 15 responding tumours and 13 non-responding tumours were selected. Regressive morphology was seen in 14/15 responders after castration therapy, compared with 4/13 non-responders. Median apoptotic index increased significantly after castration therapy for responders (from 2.6 to 3.5, p < 0.05) whereas it was 2.8 before and after therapy in non-responders. This indicates that subsequent clinical response can be predicted by the induction of regressive morphology and an increase in apoptotic index. In conclusion, immunoreactivity for Ki-67 appeared to be a putative prognostic factor in PCa, whereas the prognostic value of p53 and bcl-2 was dubious. p53 immunoreactivity did not appear to be predictive of radioresistance in PCa. Cellular response in biopsies shortly after castration therapy might be treatment-predictive.
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PMID:Prognostic factors in prostate cancer. 924 5

To develop a syngeneic transplantable system to study immunotherapeutic approaches for the treatment of prostate cancer, three cell lines were established from a heterogeneous 32 week tumor of the transgenic adenocarcinoma mouse prostate (TRAMP) model. TRAMP is a transgenic line of C57BL/6 mice harboring a construct comprised of the minimal -426/+28 rat probasin promoter driving prostate-specific epithelial expression of the SV40 large T antigen. TRAMP males develop histological prostatic intraepithelial neoplasia by 8-12 weeks of age that progress to adenocarcinoma with distant metastases by 24-30 weeks of age. The three cell lines (TRAMP-C1, TRAMP-C2, and TRAMP-C3) express cytokeratin, E-cadherin, and androgen receptor by immunohistochemical analysis and do not appear to have a mutated p53. Although TRAMP-C1 and TRAMP-C2 are tumorigenic when grafted into syngeneic C57BL/6 hosts, TRAMP-C3 grows readily in vitro but does not form tumors. The T antigen oncoprotein is not expressed by the cell lines in vitro or in vivo. The rationale for establishing multiple cell lines was to isolate cells representing various stages of cellular transformation and progression to androgen-independent metastatic disease that could be manipulated in vitro and, in combination with the TRAMP model, provide a system to investigate therapeutic interventions, such as immunotherapy prior to clinical trials.
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PMID:Characterization of prostatic epithelial cell lines derived from transgenic adenocarcinoma of the mouse prostate (TRAMP) model. 926 88


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