Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0005684 (bladder cancer)
 16,431 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bladder cancer is one of the most important diseases associated with arsenic (As) exposure in view of its high prevalence and mortality rate. Experimental studies have shown that As exposure induces cell proliferation in the bladder of sodium arsenite (iAsIII) subchronically treated mice. However, there is little available information on its effects on the cell cycle of bladder cells. Thus, our purpose was to evaluate the effects of iAsIII on cell cycle progression and the response of p53 and p21 on the human-derived epithelial bladder cell line HT1197. iAsIII treatment (1-10 microM) for 24 h induced a dose-dependent increase in the proportion of cells in S-phase, which reached 65% at the highest dose. A progressive reduction in cell proliferation was also observed. BrdU was incorporated to cellular DNA in an interrupted form, suggesting an incomplete DNA synthesis. The time-course of iAsIII effects (10 microM) showed an increase in p53 protein content and a transient increase in p21 protein levels accompanying the changes in S-phase. These effects were correlated with iAs concentrations inside the cells, which were not able to metabolize inorganic arsenic. Our findings suggest that p21 was not able to block CDK2-cyclin E complex activity and was therefore unable to arrest cells in G1 allowing their progression into the S-phase. Further studies are needed to ascertain the mechanisms underlying the effects of iAsIII on the G1 to S phase transition in bladder cells.
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PMID:Effects of arsenite on cell cycle progression in a human bladder cancer cell line. 1559 Jan 21

Dysregulation of cell cycle control may lead to genomic instability, neoplastic transformation and tumor progression. In terms of the particular roles in regulation of the cell-cycle, p21(WAF1) causes growth arrest through inhibition of cyclin-dependant kinases required for G1/S transition. P16 (INK4A) and p15 (INK4B) are thought to act as tumor suppressors, since their inactivation and/or deletion are observable in various types of malignancies. Cyclin D1 is hypothesized to control cell cycle progression through the G1-S check point. The present study evaluated p21 expression, p16 and p15 gene deletion and cylin D1 expression in bladder carcinoma among Egyptian patients, in relation to different clinicopathological features of the tumors and presence or absence of bilharziasis. Tissue specimens were obtained from 132 patients with bladder carcinoma and 50 normal tissue samples from the same patients served as control. P21 was determined by Western blot (WB) and enzyme immunoassay (EIA), p16 and p15 gene deletions were examined by polymerase chain reaction (PCR) and Cyclin D1 was detected by WB. Levels of p21 were lower in malignant tumors than in normal tissues. Lower expression of p21 was evident in lymph node positive, well differentiated tumors and squamous cell carcinoma (SCC) than in lymph node negative, poorly differentiated tumors and transitional cell carcinoma (TCC). In all normal samples, p15 and p16 genes were detected while cyclin D1 was not detected. P16 and p15 genes were deleted in 38.7% (41/106) and 30.2% (32/106) of bladder tumors respectively. The deletion of both genes was associated with poor differentiation grade and presence of bilharziasis. P16 deletion was also correlated to advancing tumor stage. Cyclin D1 was expressed in 57.5% of bladder tumors (69/120), where its expression was correlated to early stage, well differentiation grade, schistomiasis, and low levels of p21. Cell cycle is dysregulated in bladder carcinoma. This was evident from the increased expression of cyclin D1, the decreased levels of p21 and the deletion of p15 and p16 genes. Moreover, p16 and p15 gene deletion was related to tumor progression and might have a role in bilharzial bladder carcinogenesis. Cyclin D1 over-expression appears to be an early event in bladder cancer and might explain bilharzial associated bladder carcinogenesis.
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PMID:Cell cycle regulators in bladder cancer: relationship to schistosomiasis. 1559 May 62

It is well known that dietary phenolic compounds can elicit vital cellular responses such as cytotoxicity, cell cycle arrest and apoptosis by activating a cascade of molecular events. Ellagic acid is one of these phenolic compounds, but the exact mechanism of its action is still unclear. The objective of this study was to investigate ellagic acid-induced cell cycle arrest and apoptosis in T24 human bladder cancer cells in vitro. Assays were performed to determine cell viability, cell cycle arrest, apoptosis, caspases-3 activity and gene expression, measured by flow cytometric assay, polymerase chain reaction (PCR) and determination of caspase-3 activity. Ellagic acid significantly reduced the viable cells, induced G0/G1-phase arrest of the cell cycle and apoptosis. Ellagic acid also increased p53 and p21 and decreased CDK2 gene expression, that may lead to the G0/G1 arrest of T24 cells. Ellagic acid also promoted caspase-3 activity after exposure for 1, 3, 6, 12 and 24 h, which led to induction of apoptosis. Furthermore, the ellagic acid-induced apoptosis on T24 cells was blocked by the broad-spectrum caspase inhibitor (z-VAD-fmk).
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PMID:Ellagic acid induced p53/p21 expression, G1 arrest and apoptosis in human bladder cancer T24 cells. 1586 36

Evaluation of cell cycle regulators has gained special interest in the effort to increase the amount of prognostic information in malignant tumors. Minichromosome maintenance proteins (MCMs) drive the formation of prereplicative complexes, which is the first key event during G1 phase. Therefore, altered MCM expression may be a hallmark of cell cycle deregulation, which is supposed to be the most essential mechanism in the development and progression of bladder cancer. Our aim was to investigate the value of MCMs as proliferation markers and prognostic indicators in detrusor muscle-invasive urothelial bladder carcinomas. We analyzed immunohistochemically the expression of MCM-2 and MCM-5 in 65 patients with detrusor muscle-invasive urothelial bladder carcinomas in relation with clinicopathologic parameters, patients' overall and disease-free survival, and the expression of the conventional proliferation index Ki-67 and other cell cycle modulators (p53, pRb, p21(WAF1), and p27(Kip1)). The levels of MCM-2 and MCM-5 were significantly higher in high-grade (P < .0001), advanced-stage (P = .001), and nonpapillary tumors (P < .0001). The expression of MCM-2 and MCM-5 significantly associated with the conventional proliferation index Ki-67 (P = .0001 for each protein). The expression of MCM-2 or MCM-5 positively correlated with p53 labeling index (P = .014 and P = .009, respectively). Also, median p21(WAF1) labeling index was higher in MCM-5 high expressors (P = .028). Finally, both MCM-2 and MCM-5 associated significantly with adverse patients' outcome in both univariate (P = .0072 and P = .0074, respectively) and multivariate (P = .0001) analysis. In conclusion, MCM-2 and MCM-5 appear to be reliable proliferation indexes and useful prognostic markers in patients with muscle-invasive urothelial bladder carcinomas.
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PMID:Minichromosome maintenance proteins 2 and 5 expression in muscle-invasive urothelial cancer: a multivariate survival study including proliferation markers and cell cycle regulators. 1611 7

1,1-Bis(3'-indolyl)-1-(p-substitutedphenyl)methanes containing p-trifluoromethyl (DIM-C-pPhCF3), p-t-butyl (DIM-C-pPhtBu), and phenyl (DIM-C-pPhC6H5) substituents have been identified as a new class of peroxisome proliferator-activated receptor gamma (PPARgamma) agonists that exhibit antitumorigenic activity. The PPARgamma-active C-DIMs have not previously been studied against bladder cancer. We investigated the effects of the PPARgamma-active C-DIMs on bladder cancer cells in vitro and bladder tumors in vivo. In this study, the PPARgamma-active compounds inhibited the proliferation of KU7 and 253J-BV bladder cancer cells, and the corresponding IC50 values were 5 to 10 and 1 to 5 micromol/L, respectively. In the less responsive KU7 cells, the PPARgamma agonists induced caveolin-1 and p21 expression but no changes in cyclin D1 or p27; in 253J-BV cells, the PPARgamma agonists did not affect caveolin-1, cyclin D1, or p27 expression but induced p21 protein. In KU7 cells, induction of caveolin-1 by each of the PPARgamma agonists was significantly down-regulated after cotreatment with the PPARgamma antagonist GW9662. DIM-C-pPhCF3 (60 mg/kg thrice a week for 4 weeks) inhibited the growth of implanted KU7 orthotopic and s.c. tumors by 32% and 60%, respectively, and produced a corresponding decrease in proliferation index. Treatment of KU7 cells with DIM-C-pPhCF3 also elevated caveolin-1 expression by 25% to 30%, suggesting a role for this protein in mediating the antitumorigenic activity of DIM-C-pPhCF3 in bladder cancer.
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PMID:Inhibition of bladder tumor growth by 1,1-bis(3'-indolyl)-1-(p-substitutedphenyl)methanes: a new class of peroxisome proliferator-activated receptor gamma agonists. 1639 56

Curcumin, a polyphenol compound derived from Curcuma longa Linn, has been recognized as a promising anti-cancer drug due to its multiple properties including anti-inflammatory, anti-oxidant and anti-carcinogenic activities. To elucidate the mechanisms by which curcumin inhibits human bladder carcinoma T24 cell proliferation, we tested the effects of curcumin on specific cell cycle pathways and on the expression of cyclooxygenases (COXs). Curcumin inhibited the growth of T24 cells and induced G2/M arrest in a concentration-dependent manner, effects associated with the down-regulation of cyclin A and up-regulation of cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1). However, other G2/M regulatory molecules, such as cyclin A, Cdc2, Cdk2, Wee1 and Cdc25C, were not modulated by curcumin treatment. Furthermore, curcumin decreased the levels of COX-2 mRNA and protein expression without significant changes in the levels of COX-1, which correlated with a decrease in prostaglandin E2 (PGE2) synthesis. These observations suggest that curcumin may have therapeutic potential for bladder cancer patients.
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PMID:Induction of G2/M arrest and inhibition of cyclooxygenase-2 activity by curcumin in human bladder cancer T24 cells. 1659 91

Transitional cell carcinoma of the bladder is a common tumor. While most patients presenting superficial disease can be expected to do well following treatment, still many patients will return to our office with muscle invasive and metastatic disease. Survival in advanced bladder cancer is less than 50%. Tumors of similar histologic grade and stage have variable behavior, suggesting that genetic alterations must be present to explain the diverse behavior of bladder cancer. It is hoped that through the study of the subtle genetic alterations in bladder cancer, important prognostic and therapeutic targets can be exploited. Many new diagnostic tests and gene therapy approaches rely on the identification and targeting of these unique genetic alterations. A review of literature published on the molecular genetics of bladder cancer from 1970 to the present was conducted. A variety of molecular genetic alterations have been identified in bladder cancer. Oncogenes (H-ras, erbB-2, EGFR, MDM2, C-MYC, CCND1), tumor suppressor genes (p53, Rb, p21, p27/KIP1, p16, PTEN, STK15, FHIT, FEZ1/LZTS1, bc10), telomerase, and methylation have all been studied in bladder cancer. Several have proven to be potentially useful clinical targets in the prognosis and therapy of bladder cancer such as staining for p53 and gene therapy strategies such as p53 and fez1. Clinical trials targeting HER2/neu and the EGFR pathways are underway. The UroVysion bladder cancer assay relies on FISH to detect genetic alterations in this disease. Continuing identification of the molecular genetic alterations in bladder cancer will enhance future diagnostic and therapeutic approaches to bladder cancer. Capitalizing on these alterations will allow early detection, providing important prognostic information and unique targets for gene therapy and other therapeutic approaches.
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PMID:Molecular genetics of bladder cancer: targets for diagnosis and therapy. 1691 24

The objective of this study was to determine the correlation of the expression of cyclin D1 and E1 with the expression of commonly altered cell cycle regulators and bladder cancer presence, staging, and clinical outcomes. We performed immunohistochemical staining for cyclin D1, cyclin E1, p53, p21, p27, and retinoblastoma protein (pRB) on serial cuts from normal urothelium from 9 controls, radical cystectomy specimens from 226 consecutive patients with advanced transitional cell carcinoma, and lymph nodes with metastasis from 50 of the 226 cystectomy patients. Cyclin D1 and E1 immunoreactivity were considered low when samples demonstrated less than 10% and 30% nuclear reactivity, respectively. Normal bladder urothelium from all 9 control patients showed uniformly intense expression of cyclin D1 and E1. Cyclin D1 expression was low in 99 (43.8%) of 226 cystectomy specimens and 25 (50.0%) of 50 metastatic lymph node specimens. Cyclin D1 immunoreactivity was not associated with any pathologic characteristics or clinical outcomes. Cyclin E1 expression was low in 125 (55.3%) of 226 cystectomy specimens and 22 (44.0%) of 50 metastatic lymph node specimens. Low cyclin E1 expression was significantly associated with advanced pathologic stage, lymphovascular invasion, and lymph node metastases. In multivariate analyses, low cyclin E1 expression was significantly associated with bladder cancer-specific mortality (P = .048), but not disease recurrence (P = .056). Low cyclin E1 expression was significantly associated with altered expression of pRB, p27, and cyclin D1. Low cyclin D1 expression was significantly associated with altered expression of pRB, p21, and cyclin E1. Cyclin E1 expression stratifies patients with bladder transitional cell carcinoma into those with more "indolent" behavior and those with features of biologically and clinically aggressive disease.
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PMID:Correlation of cyclin D1 and E1 expression with bladder cancer presence, invasion, progression, and metastasis. 1694 11

The long-term disease-free survival in patients with metastatic transitional cell carcinoma (TCC) is still considerably low. Novel chemotherapeutic agents are needed to decrease the morbidity and mortality of TCC. In this study, we have evaluated several epigenetic modifiers for their therapeutic application in bladder cancer. Both histone deacetylase inhibitors (FK228, TSA) and DNA hypomethylating agent (5-Azacytidine) were tested using in vitro assays such as cell viability, cell cycle analysis and western blot to determine their mechanisms of action. Drug combination experiments were also designed to study any additive or synergistic effects of these agents. In addition, two bladder cancer xenograft models (one subcutaneous and one orthotopic) were employed to assess the therapeutic efficacy of these agents in vivo. Three agents exhibited various growth inhibitory effects on 5 different TCC cell lines in a dose- and time-dependent manner. In addition to G2/M cell cycle arrest, FK228 is more potent in inducting apoptosis than the two other single agents, and combination of both FK228 and 5-Aza further enhances this effect. p21 induction is closely associated with FK228 or TSA but not 5-Aza, which is mediated via p53-independent pathway. Consistent with in vitro results, FK228 exhibited a significant in vivo growth inhibition of TCC tumor in both subcutaneous and orthotopic xenograft models. FK228 is a potent chemotherapeutic agent for TCC in vivo with minimal undesirable side effects. The elevated p21 level mediated via p53 independent pathway is a hallmark of FK228 mechanism of action.
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PMID:The use of histone deacetylase inhibitor FK228 and DNA hypomethylation agent 5-azacytidine in human bladder cancer therapy. 1723 May 11

More than 35% of human urinary bladder cancers involve oncogenic H-Ras activation. In addition to tumorigenic ability, oncogenic H-Ras possesses a novel proapoptotic ability to facilitate the induction of apoptosis by histone deacetylase inhibitors (HDACI). HDACIs are a new class of anticancer agents and are highly cytotoxic to transformed cells. To understand the connection between the selectivity of HDACIs on transformed cells and the proapoptotic ability of oncogenic H-Ras to facilitate HDACI-induced apoptosis, we introduced oncogenic H-Ras into urinary bladder J82 cancer cells to mimic an acquisition of the H-ras gene activation in tumor development. Expression of oncogenic H-Ras promoted J82 cells to acquire tumorigenic ability. Meanwhile, oncogenic H-Ras increased susceptibility of J82 cells to HDACIs, including FR901228 and trichostatin A, for inducing apoptosis. The caspase pathways, the B-Raf and extracellular signal-regulated kinase pathway, p21(Cip1) and p27(Kip1), and core histone contents are regulated differently by FR901228 in oncogenic H-Ras-expressed J82 cells than their counterparts in parental J82 cells, contributing to the increased susceptibility to the induction of selective apoptosis. Our results lead us to a suggestion that HDACIs activate the proapoptotic ability of oncogenic H-Ras, indicating a potential therapeutic value of this new class of anticancer agents in the control of human urinary bladder cancer that has progressed to acquire oncogenic H-Ras.
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PMID:Proapoptotic ability of oncogenic H-Ras to facilitate apoptosis induced by histone deacetylase inhibitors in human cancer cells. 1736 3


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