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)

Decreased expression of the Ca(2+)-dependent cell adhesion molecule E-cadherin is observed in several poorly differentiated carcinomas and is presumably associated with an invasive phenotype of these tumors. Evidence accumulated so far indicates that decreased transcription is a major mechanism leading to defective E-cadherin function. Therefore, we isolated and characterized the human E-cadherin gene promoter and studied the transcriptional regulation of this gene in two human prostate cancer cell lines, one expressing E-cadherin (PC-3), the other one not expressing E-cadherin (TSU-pr1). We show that the E-cadherin promoter is not active in the non-expressing cells and that this may be due to the binding of a repressor protein to the promoter.
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PMID:Transcriptional regulation of the human E-cadherin gene in human prostate cancer cell lines: characterization of the human E-cadherin gene promoter. 809 45

The cadherins are a family of transmembrane glycoproteins responsible for calcium-dependent cell-cell adhesion. This adhesion is mediated by a group of cytoplasmic proteins, the catenins, which act inside the cell to couple the cadherin molecule to the microfilament cytoskeleton. Dysfunction of E-cadherin-dependent cell-cell adhesion has been demonstrated to contribute to the acquisition of invasive potential of malignant adenocarcinoma cells. The potential role of alterations of catenin expression in tumor cell invasion is largely unexplored. We have previously found that E-cadherin is frequently down-regulated in clinical samples of prostate cancer (Umbas, R., Schalken, J. A., Aalders, T. W., Carter, B. S., Karthaus, H. F. M., Schaafsma, H. E., Debruyne, F. M. J., and Isaacs, W. B. Cancer Res., 52: 5104-5109, 1992). In this study, we further investigate this adhesion system in both benign and malignant human prostate cells in culture. Using antibodies to E-cadherin and its cytoplasmic accessory protein, alpha-catenin, we find that 5 of 6 human prostate cancer cell lines have reduced or absent levels of one or the other or both of these molecules when compared to normal prostatic epithelial cells. Only the LNCaP prostate cancer cell line is indistinguishable from normal prostate epithelium with respect to its E-cadherin-alpha-catenin complement. Interestingly, the PC-3 line is characterized by the presence of E-cadherin, but the complete lack of alpha-catenin found at both the RNA and protein level. This lack of alpha-catenin gene expression is explained by Southern analysis, which reveals a homozygous deletion of a large portion of the alpha-catenin gene in PC-3 cells. This loss of alpha-catenin is functionally manifested by negligible Ca(2+)-dependent aggregation of these cells in vitro, when compared to LNCaP cells. These results confirm that E-cadherin-dependent cell-cell adhesion is frequently aberrant in prostate cancer cells, and suggest that in a subset of prostate cancers, this adhesion may be inactivated by loss of alpha-catenin rather than E-cadherin itself. Furthermore, these results demonstrate that mutational inactivation of the alpha-catenin gene is one mechanism responsible for the loss of normal cell-cell adhesion in prostate cancer.
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PMID:Reduction of E-cadherin levels and deletion of the alpha-catenin gene in human prostate cancer cells. 833 65

Immunohistochemical studies have suggested that E-cadherin may be a useful prognostic marker in prostate cancer. Previous studies have depended on cryostat sections of tissues selected grossly. Many prostate cancers, even when extensive, are not visible grossly; many others cannot be demarcated sharply grossly. The wide applicability of prognostic markers after total prostatectomy will depend upon methods that can be applied to tissue selected based upon the histopathological examination of the entire prostate. Our purpose was to investigate the possibility that E-cadherin could be demonstrated in paraffin-embedded whole prostates and metastatic prostate cancer. Microwaving in citrate buffer was the best of five methods tested for the demonstration of E-cadherin in paraffin-embedded prostate and was used to investigate 53 primary prostate cancers from 44 patients and lymph node metastases from 14 patients. Metastases of prostate cancer to lymph nodes expressed less (P = 0.008) E-cadherin than primary prostate cancers. The expression of E-cadherin correlated with the histopathological differentiation (Gleason grade) of primary prostate cancers (P = 0.03, Ptrend = 0.003). The use of monoclonal anti-human E-cadherin (HECD-1) with microwaving in citrate buffer followed by immunoperoxidase staining with heavy metal enhancement for the demonstration of E-cadherin in paraffin-embedded tissue will, for the first time, allow the use of archival tissue for prognostic studies of E-cadherin in prostate cancer and other tissue. Our results are consistent with the hypothesis that aggressive prostate cancers exhibit decreased expression of E-cadherin and demonstrate the feasibility of long-term prognostic studies of this molecule in the usually multiple prostate cancers found in whole, formalin-fixed, paraffin-embedded resected prostates.
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PMID:Expression of E-cadherin in primary and metastatic prostate cancer. 862 9

Using specific ELISA kits, we investigated the secretion of cytokines in five human prostate carcinoma cell lines: ALVA 31, DU145, LNCaP, ND1 and PC3. Three of the five cell lines investigated secreted granulocyte-macrophage colony-stimulating factor (GM-CSF); GM-CSF was not identified in ALVA31 or LNCaP. In addition, we have shown that conditioned media of DU145, ND1 and PC3 stimulated proliferation of the GM-CSF-dependent cell line MO7e indicating that these cells secrete biologically active GM-CSF. By flow cytometric analysis we determined that all five cell lines expressed the alpha-subunit of the GM-CSF receptor on the cell surface but only ALVA31 expressed both the alpha- and beta-subunits of the GM-CSF receptor. Varying concentrations of GM-CSF did not stimulate the proliferation rate of any of the prostate carcinoma cell lines. Thus, there does not appear to be autocrine loop of GM-CSF-induced proliferation. However, the expression of E-cadherin and endoglin (CD105) was modulated under GM-CSF treatment in ALVA31. In addition, GM-CSF decreased the level of soluble CD44 in ND1. These results suggest that the GM-CSF receptor alpha-subunit may play a role in metabolic activity of prostate cancer.
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PMID:Human prostate carcinoma cell lines secrete GM-CSF and express GM-CSF-receptor on their cell surface. 868 98

A number of genetic changes have been documented in prostate cancer, ranging from allelic loss to point mutations and changes in DNA methylation patterns. Up to now among the most consistent changes are those of allelic loss events, with the majority of tumours examined showing loss of alleles from at least one chromosomal arm. Chromosomes 8 and 13 appear to be the most frequently affected, with the former showing both loss of alleles from the short arm and gain of sequences on the long arm. Deletions of one copy of the RB gene are common, whereas deletion and/or point mutation of the TP53 gene is a less frequent event, at least in clinically localized tumours. Alterations in the E-cadherin/alpha catenin mediated cell-cell adhesion mechanism appear to be present in over one third of all prostate cancers and may be critical to the acquisition of metastatic potential of aggressive prostate cancers. In addition, altered DNA methylation patterns have been found in the majority of prostate cancers examined, suggesting an important role for methylation modulated gene expression in prostate carcinogenesis. Finally, the existence of prostate cancer susceptibility genes is suggested by study of familial clustering of prostate cancer, and it is expected that the identification of these genes will provide insight into critical rate limiting steps in the carcinogenic pathway of both inherited and sporadic disease.
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PMID:Molecular genetics of prostate cancer. 871 27

We have previously reported the development of a transgenic mouse model for prostate cancer derived from PB-Tag transgenic line 8247, henceforth designated the TRAMP (transgenic adenocarcinoma mouse prostate) model. We now describe the temporal and spatial consequences of transgene expression and report the identification and characterization of metastatic disease in the TRAMP model. TRAMP mice characteristically express the T antigen oncoprotein by 8 weeks of age and develop distinct pathology in the epithelium of the dorsolateral prostate by 10 weeks of age. Distant site metastases can be detected as early as 12 weeks of age. The common sites of metastases are the periaortic lymph nodes and lungs, with occasional metastases to the kidney, adrenal gland, and bone. By 28 weeks of age, 100% harbor metastatic prostate cancer in the lymph nodes or lungs. We have also demonstrated the loss of normal E-cadherin expression, as observed in human prostate cancer, as primary tumors become less differentiated and metastasize. The TRAMP model provides a consistent source of primary and metastatic tumors for histopathobiological and molecular analysis to further define the earliest molecular events involved in the genesis, progression, and metastasis of prostate cancer.
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PMID:Metastatic prostate cancer in a transgenic mouse. 879 72

Human prostate cancers frequently show loss of heterozygosity (LOH) at loci on the long arm of chromosome 16 (16q). In this study, we analyzed prostate cancer specimens from 48 patients (Stage B, 20 cases; Stage C, 10 cases; cancer death, 18 cases) for allelic loss on 16q, using either restriction fragment length polymorphism (RFLP)- or polymerase chain reaction (PCR)-based methods. Allelic losses were observed in 20 (42%) of 48 cases, all of which were informative with at least one locus. Detailed deletion mapping identified three distinct commonly deleted regions on this chromosome arm: q22.1-q22.3, q23.2-q24.1, and q24.3-qter. On the basis of a published sex-averaged framework map, the estimated sizes of the commonly deleted regions were 4.7 (16q22.1-q22.3), 17.2 (16q23.2-q24.1) and 8.4 cM (16q24.3-qter). Allelic losses on 16q were observed more frequently in the cancer-death cases (11 of 18; 61%) than in early-stage tumor cases (9 of 30; 30%; P < 0.05). In 7 of 11 patients from whom DNA was available from metastatic cancers as well as from normal tissues and primary tumors, the primary cancer foci had no detectable abnormality of 16q, but the metastatic tumors showed LOH. These results suggest that inactivation of tumor suppressor genes on 16q plays an important role in the progression of prostate cancer. We also analyzed exons 5-8 of the E-cadherin gene, located at 16q22.1, in tumor DNA by means of PCR-single strand conformation polymorphism and direct sequencing, but we detected no somatic mutations in this candidate gene.
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PMID:Three distinct commonly deleted regions of chromosome arm 16q in human primary and metastatic prostate cancers. 894 4

Cell adhesion molecules (CAMs) are important in cell-cell interaction and interactions between cells and components of the extracellular matrix. CAMs have been associated with invasion and metastasis in a wide variety of human malignancies, including tumors of the genitourinary tract. Cadherins are transmembrane glycoproteins that bind cells by homophilic, homotypic interactions. Loss of expression of E-cadherin has been associated with dedifferentiation, invasion, and metastasis in prostate cancer and transitional cell neoplasia of the urinary bladder. CD44, a family of transmembrane glycoproteins principally involved in cell-extracellular matrix interactions, also has been associated with invasion and metastasis in urologic malignancies. Through alternative splicing, a variety of CD44 isoforms can be expressed that can undergo extensive posttranslational modification. CD44 variants have been associated with metastasis in a variety of human malignancies, particularly in the gastrointestinal system. Although loss of expression of CD44 standard form has been associated with aggressive prostate gland and bladder cancers, no specific isoform has been associated with metastasis of these neoplasms. Integrins are transmembrane glycoproteins with wide cellular distribution that bind a variety of extracellular matrix components. Integrins have been studied extensively in prostate cancer in which altered integrin expression has been associated with malignant prostatic epithelium. Additional adhesion molecules that have been studied to a variable degree in urologic malignancies include selectins and the immunoglobulin super-family. CAMs are fundamental to diverse biologic processes and appear capable of regulating intracellular signaling events that appear to have significant importance in human malignancy, including cancers of the urogenital tract.
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PMID:Cellular adhesion molecules in urologic malignancies. 898 Mar 68

Adhesion molecules play an important role in organogenesis, would healing, inflammation, and progression of malignant tumors. Three major classes of adhesion molecules may be discriminated by function: (a) calcium-dependent homotypic adhesion molecules (e.g. cadherins), (b) substrate adhesion molecules (e.g. integrins) and (c) heterotypic adhesion molecules (e.g. ICAM-1). Molecules of each of the three classes have been identified in urologic tumors. Results of research on substrate adhesion molecules and heterotypic adhesion molecules have not yet led to new clinical concepts. In contrast, loss of E-cadherin in tumors of the bladder and prostate has been clearly associated with de-differentiation of tumors and diminished survival of patients. Loss of another adhesion molecule, C-CAM, has been observed in prostate cancer. This has led to new therapeutic approaches, which are in an experimental stage at present. It may be expected that, in the future, new therapeutic concepts will be based on research on adhesion molecules in urologic tumors.
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PMID:[Adhesion molecules in urologic tumors]. 899 27

Current androgen ablation therapies for advanced prostate cancer are not curative. Several recently identified critical biochemical pathways, including the E-cadherin/catenin complex, programmed cell death, telomerase activity, and receptor kinases, may represent targets for new therapeutic approaches. Different forms of gene therapy are also being investigated. Drug development is at the pre-clinical stage, but phase I and II clinical trials are planned, and may lead to a wider choice of therapeutic options for prostate cancer in the not too distant future.
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PMID:New perspectives in the treatment of prostate cancer. 907 7


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