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)

E-cadherin is a Ca(2+)-dependent cell adhesion molecule which plays an important role in normal growth and development via mediation of homotypic, homophilic cell-cell interaction. Recent studies suggest that E-cadherin may be important in neoplastic progression as well, particularly as a suppressor of invasion. We have previously demonstrated that the invasive phenotype of rat prostate cancer cells is associated with the decreased expression of E-cadherin (M. J. G. Bussemakers, R. J. A. Van Moorselaar, L. A. Giroldi, T. Ichikawa, J. T. Isaacs, F. M. J. Debruyne, and J. A. Schalken, Cancer Res., 52:2916-2922, 1992). This is of particular interest, since the locus to which the human E-cadherin gene is mapped is frequently involved in allelic loss in prostate cancer (B. S. Carter, C. M. Ewing, W. S. Ward, B. F. Treiger, T. W. Aalders, J. A. Schalken, J. I. Epstein, and W. B. Isaacs, Proc. Natl. Acad. Sci. USA, 87:8751-8755, 1990; U. S. Bergerheim, K. Kunimi, V. P. Collins, and P. Ekman, Genes, Chromosomes Cancer, 3: 215-220, 1991). Impaired E-cadherin function is likely to be associated with aberrant expression of the protein. We therefore analyzed E-cadherin expression in situ by immunohistochemistry in nonmalignant and malignant specimens of human prostatic tissue. Of 92 tumor samples of either primary or metastatic deposits of prostate cancer, 46 had reduced or absent E-cadherin staining when compared to nomalignant prostate, which uniformly stained strongly positive. There was a statistically significant correlation between the decreased expression of E-cadherin and loss of tumor differentiation. Additionally, certain tumors within a histologically similar group could be distinguished by the presence of mixed populations of E-cadherin-negative and -positive cells. The percentage of tumors with aberrant E-cadherin staining increased when clinically localized tumors were compared to either tumors with extensive local progression or metastatic deposits of prostate cancer, suggesting a correlation between loss of E-cadherin and tumor progression. Taken together, these findings suggest that further exploration of E-cadherin as a candidate invasion suppressor molecule in human prostate cancer is warranted.
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PMID:Expression of the cellular adhesion molecule E-cadherin is reduced or absent in high-grade prostate cancer. 151 67

Cadherins represent a family of Ca(2+)-dependent cell adhesion molecules involved in homotypic, homophilic cell-cell interactions. Recent studies have shown that the cadherins can play a role in invasive and metastatic behavior. Using the established Dunning R-3327 model system of serially transplantable rat prostate cancers, the expression of E- and P-cadherin in rat prostatic cancer was studied. Analysis within this system demonstrated that whereas E-cadherin was expressed in the normal rat prostate and the well- or moderately differentiated, noninvasive Dunning tumors, no expression, either at the mRNA or at the protein level, could be detected in the invasive sublines. Since not all invasive Dunning tumors studied have metastatic ability, these results suggest that a decreased expression of E-cadherin is correlated with invasive behavior rather than with metastatic ability. Recently, genetic instability occurred in an animal bearing the well differentiated, androgen-responsive, slow growing, nonmetastatic Dunning R-3327-H rat prostate cancer resulting in the progression to an anaplastic, androgen-independent, fast growing, highly metastatic state. This spontaneously arising tumor, termed the AT6 subline, in its original host was heterogeneously composed of both a well differentiated and an anaplastic population of cancer cells in which areas of squamous cell differentiation were occasionally observed. The original animal bearing this heterogeneous AT6 cancer developed multiple metastases, the lung metastases being heterogeneously composed of anaplastic and squamous cell populations. Cytogenetic analysis demonstrated that the lung metastases were derived from a specific subpopulation of cancer cells present in the original AT6 primary tumor. Immunohistochemical studies demonstrated that only the area of lung metastases displaying squamous morphology were positive for E-cadherin. In contrast, the anaplastic areas of the lung metastases and the metastases in other organs were E-cadherin negative. By the first passage of the AT6 tumor only the anaplastic cells were present and no detectable E-cadherin mRNA or protein was found in the primary tumor and metastatic deposits. These results suggest that a decreased expression of E-cadherin is associated with the progression of prostatic cancer.
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PMID:Decreased expression of E-cadherin in the progression of rat prostatic cancer. 158 9

Decreased levels of the cell-cell adhesion molecule E-cadherin are associated with loss of differentiation in a number of human carcinomas. However, the value of E-cadherin as a prognostic marker in these cancers is largely undetermined. A previous study of E-cadherin levels in prostate cancer revealed that almost 50% of tumors examined had reduced or absent levels of this protein (Umbas et al., Cancer Res., 52: 5104-5109, 1992). To determine the potential prognostic significance of this finding, prostate cancer specimens from 89 patients were evaluated immunohistochemically for E-cadherin expression, and the results were related to histopathological grade, tumor stage, presence of metastases, and survival. As previously observed, a significant inverse correlation was found between E-cadherin expression and tumor grade. Importantly, we also found significant correlations between E-cadherin expression and tumor stage and overall survival. Sixty-three percent of the tumors that extended beyond the prostate capsule (T3-4) versus 33% of the tumors confined to the prostate (T1-2) had aberrant expression (chi 2 = 8.1, P < 0.005). Seventy-six percent of the primary tumors from patients that presented with metastases showed aberrant staining compared to 32% from patients without metastases (chi 2 = 14.9; P < 0.001). The life table analysis showed a significantly higher survival rate for patients with normal staining compared to patients with aberrant expression (chi 2 = 20.4, P < 0.001 by log rank test). Moreover, abnormal expression of E-cadherin correlated significantly with progression after radical prostatectomy (P < 0.005). These results suggest that E-cadherin expression can serve as a prognostic indicator for the biological potential of prostate cancer.
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PMID:Decreased E-cadherin expression is associated with poor prognosis in patients with prostate cancer. 751 46

Considerable evidence now exists to support an important role for the E-cadherin-mediated cell-cell adhesion pathway as a suppressor of the invasive phenotype in adenocarcinoma cells. Previous studies have found that this pathway is frequently aberrant in prostate cancers, particularly those that are likely to metastasize. In this study, we report on the effects of re-establishment of this pathway in a prostate cancer cell line, PC-3, in which this adhesion system is dysfunctional by virtue of a deletion of the gene that codes for alpha-catenin, an E-cadherin-associated protein necessary for normal E-cadherin function. Re-expression of alpha-catenin was accomplished either by transfection of PC-3 cells with a copy of the alpha-catenin cDNA under the control of a heterologous promoter or by microcell-mediated transfer of chromosome 5, which contains the alpha-catenin gene and its normal regulatory elements. In both cases, re-expression of alpha-catenin is associated with a similar, dramatic alteration in cell morphology, whereby extensive cell-cell contact is observed. In the case of transfection of the cDNA, this expression is only transient, because the transfected cells either cease to proliferate or, more commonly, revert to the parental phenotype with concomitant cessation of alpha-catenin expression. In contrast, cells containing one or more copies of microcell-transferred chromosome 5 express alpha-catenin in a stable manner and continue to proliferate. Upon injection into nude mice, these latter cells are no longer tumorigenic, or form only slowly growing tumors with greatly extended doubling times when compared to the parental PC-3 cells. During passage in culture, clones that contain only one transferred copy of chromosome 5 reproducibly revert to the parental phenotype. This reversion is associated with loss of the chromosome 5 region containing the alpha-catenin gene and consequent loss of alpha-catenin expression, as well as re-emergence of tumorigenicity. Transfer of chromosome 5 into prostate cancer cells that are E-cadherin negative does not result in either morphological transformation or suppression of tumorigenicity, suggesting that these effects of alpha-catenin expression are dependent upon concomitant expression of E-cadherin. These data demonstrate the tumor suppressive ability of chromosome 5 in the PC-3 prostate cancer cells and suggest that re-expression of alpha-catenin with resultant restoration of E-cadherin function plays a critical role in this process.
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PMID:Chromosome 5 suppresses tumorigenicity of PC3 prostate cancer cells: correlation with re-expression of alpha-catenin and restoration of E-cadherin function. 758 12

A number of genetic changes have been documented in prostate cancer, ranging from allelic loss to point mutations and changes in DNA methylation patterns (summarized in Fig. 1). To date, the most consistent changes are those of allelic loss events, with the majority of tumors examined showing loss of alleles from at least one chromosomal arm. The short arm of chromosome 8, followed by the long arm of chromosome 16, appear to be the most frequent regions of loss, suggesting the presence of novel tumor suppressor genes. Deletions of one copy of the Rb and p53 genes are less frequent, as are mutations of the p53 gene, and accumulating evidence suggests the presence of an additional tumor suppressor gene on chromosome 17p, which is frequently inactivated in prostate cancer. Alterations in the E-cadherin/alpha-catenin-mediated cell-cell adhesion mechanism appear to be present in almost half of all prostate cancers and may be critical to the acquisition of metastatic potential of aggressive prostate cancers. Finally, altered DNA methylation patterns have been found in the majority of prostate cancers examined, suggesting widespread alterations in methylation-modulated gene expression. The presence of multiple changes in these tumors is consistent with the multistep nature of the transformation process. Finally, efforts to identify prostate cancer susceptibility loci are under way and may elucidate critical early events in prostatic carcinogenesis.
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PMID:Genetic alterations in prostate cancer. 758 26

A number of genetic changes have been documented in prostate cancer, ranging from allelic loss to point mutations and changes in DNA methylation patterns (summarized in Fig. 1). The most consistent changes seen are those of allelic loss events, with the majority of tumours examined showing loss of alleles from at least one chromosomal arm. The short arm of chromosome 8, followed by the long arm of chromosome 16, seem to be the most frequent regions of loss, suggesting the presence of novel tumour suppressor genes. Deletions of one copy of the RB and TP53 genes are less frequent as are mutations of the TP53 gene, and accumulating evidence suggests the presence of an additional tumour suppressor gene on chromosome 17p, which is frequently inactivated in prostate cancer. Alterations in the E-cadherin/alpha catenin mediated cell-cell adhesion mechanism appear to be present in almost half of all prostate cancers and may be critical to the acquisition of metastatic potential of aggressive prostate cancers. Finally, altered DNA methylation patterns have been found in the majority of prostate cancers examined, suggesting widespread alterations in methylation modulated gene expression. The presence of multiple changes in these tumours is consistent with the multistep nature of the transformation process. Finally, efforts to identify prostate cancer susceptibility loci are under way, which may elucidate critical early events in prostatic carcinogenesis.
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PMID:Molecular biology of prostate cancer progression. 762 57

There is convincing evidence that a reduced expression of the E-cadherin cell-cell adhesion molecule associates with low tumor grade and poor prognosis in prostate cancer patients. However, little is known on how E-cadherin levels are regulated in human prostate cancer cells. We have inspected the effect of both androgens and estrogen on the expression of E-cadherin in the hormone-responsive LNCaP prostate tumor cell line, which is endowed with both androgen and estrogen receptors. Using both Dot Blot analysis and immunocytochemistry we have observed that either steroid significantly increased E-cadherin levels in these cells; this effect was not reversed by the simultaneous addition of the relevant antagonist, hydroxyflutamide or ICI-182,780.
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PMID:Sex steroids up-regulate E-cadherin expression in hormone-responsive LNCaP human prostate cancer cells. 762 77

Decreased E-cadherin expression assessed by immunohistochemistry correlates with poor survival of bladder and prostate cancer patients. The clinical usefulness of this parameter should therefore be evaluated in a large-scale prospective study. E-cadherin is an epithelial cell-cell adhesion molecule and impaired function presumably leads to increased invasive capacity of the cells. It has been shown that defective function can result from several mechanisms: mutation of the gene, alteration of transcription, posttranslational modification or changes in the interaction of E-cadherin with cytoskeleton anchoring proteins--the catenins. A major mechanism leading to decreased E-cadherin expression in tumors lies in decreased transcription of the gene. Hence, a better understanding of the regulation of E-cadherin transcription might open avenues for therapy by restoring normal expression.
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PMID:Defective E-cadherin function in urological cancers: clinical implications and molecular mechanisms. 765 35

This report summarizes the current knowledge with respect to genetic changes associated with the development of prostate cancer. The relation between the occurrence of these changes and the stage of the disease is by far not clear yet, albeit that some tendencies become more or less evident. In Fig. 2 these are summarized. Whereas changes on 7q and loss or gain of the X chromosome are not consistently found by either RFLP or ISH analysis, other changes are (8p-, 10p-, 10q, 16q-, and 18q-). Clearly the picture is far from complete and even more the relevant genes on these chromosomes are not defined. E-cadherin was considered a good candidate and indeed the value as progression marker is great. However, the studies so far indicate that E-cadherin does not behave as a classical type I suppressor gene and the relation with 16q loss remains to be established. The data available to date regarding chromosomal changes in prostate cancer are limited. Many studies have to be pursued to identify the consistent changes, and moreover, to map the relevant loci harbouring the genes that are implicated in the development of this disease. This knowledge will be critical in the design of appropriate diagnostic methods and possibly clues towards therapy.
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PMID:Cytogenetics of prostate cancer. Consensus Conference on Diagnosis and Prognostic Parameters in Localized Prostate Cancer. Stockholm, Sweden, May 12-13, 1993. 781 61

A number of genetic changes have been documented in prostate cancer, ranging from allelic loss to point mutations and changes in DNA methylation patterns (summarized in Fig 1). To date, the most consistent changes are those of allelic loss events, with the majority of tumors examined showing loss of alleles from at least one chromosomal arm. The short arm of chromosome 8, followed by the long arm of chromosome 16 appear to be the most frequent regions of loss, suggesting the presence of novel tumor suppressor genes. Deletions of one copy of the Rb and p53 genes are less frequent as are mutations of the p53 gene, and accumulating evidence suggests the presence of an additional tumor suppressor gene on chromosome 17p, which is frequently inactivated in prostate cancer. Alterations in the E-cadherin/alpha catenin mediated cell-cell adhesion mechanism appear to be present in almost half of all prostate cancers, and may be critical to the acquisition of metastatic potential of aggressive prostate cancers. Finally, altered DNA methylation patterns have been found in the majority of prostate cancers examined, suggesting widespread alterations in methylation-modulated gene expression. The presence of multiple changes in these tumors is consistent with the multistep nature of the transformation process. Finally, efforts to identify prostate cancer susceptibility loci are underway and will hopefully elucidate critical early events in prostatic carcinogenesis.
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PMID:Molecular biology of prostate cancer. 793 45


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