Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0005684 (
bladder cancer
)
16,431
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Studies in fibroblasts have shown that H2O2, as a model for oxidative damage, leads to a G1 growth arrest phenotypically similar to senescence. These observations as well as the observation that
bladder cancer
is associated with deletions of CDKN2, a gene important in normal senescence, led us to examine normal urothelial cell response to H2O2. We hypothesized that low dose H2O2 exposure would lead to p16 and/or p14arf mediated senescence. We show that H2O2 leads to endogenous beta-galactosidase expression similar to senescence, but instead of G1 arrest, it leads to G2/M growth arrest without induction of either p16 or p14arf. Lack of
p21
induction and a similar G2/M growth arrest in E6 immortalized uroepithelial cells suggests that this response is independent of p53 as well. An increased level of cdc2 tyrosine-15 phosphorylation following H2O2 treatment suggests that the observed growth arrest is mediated by a G2 checkpoint mechanism.
...
PMID:A G2/M growth arrest response to low-dose intermittent H2O2 in normal uroepithelial cells. 1093 79
Immunoreactivity of p21WAF1/CIP1 and cyclin D1 proteins was assessed in a cohort of 207 patients with superficial (pTa-pT1)
bladder cancer
followed up for a mean of 4.9 years. The results of the immunostainings were compared with T category, WHO grade, tumor cell proliferation rate (MIB-1 score), the expressions of p53 and bcl-2 as well as survival. Sixty-eight percent and 75% of the tumors were p21WAF1/CIP1 positive (> or = 5% of cells positive) and cyclin D1 positive (> or = 10% of cells positive), respectively. The p21WAF1/CIP1 expression was related to cyclin D1 immunolabelling (P < 0.001) but not to the other variables studied. The expression of cyclin D1 was inversely associated with T category (P = 0.001), WHO grade (P = 0.006), MIB-1 score (P = 0.014), p53 expression (P = 0.001), and bcl-2 (P = 0.011) immunoreactivity. In univariate analysis, T category (P = 0.0001), WHO grade (P < 0.0001), MIB-1 score (P < 0.0001), bcl-2 (P = 0.0092), p53 (P = 0.0016) and p21WAF1/CIP1 (P = 0.009) expressions were significant prognostic factors with regard to tumor progression, whereas cyclin D1 was without any prognostic significance (P = 0.1). Out of 123
p21
positive tumors 21 progressed, whereas only 2 out of 58
p21
negative tumors progressed. In multivariate analysis, the MIB-1 score was the only independent predictor of cancer-specific survival (P = 0.03), whereas tumor grade (P = 0.002) and cyclin D1 expression (P = 0.04) were independent predictors of tumor recurrence. Only the WHO grade (P = 0.04) retained its prognostic value indicating the risk of progression. We suggest that in superficial
bladder cancer
p21WAF1/CIP1 and cyclin D1 immunohistochemistry provide no additional prognostic information compared with already established prognostic factors for predicting the risk of progressive disease.
...
PMID:Evaluation of p21WAF1/CIP1 and cyclin D1 expression in the progression of superficial bladder cancer. Finbladder Group. 1112 4
The inhibitor of cyclin-dependent kinases WAF1 gene product
p21
is able to arrest mammalian cell cycle by mediating p53 and other factors. The prognostic value and interrelationships between
p21
expression and various parameters in
bladder cancer
have not been fully elucidated. We retrospectively investigated the immunohistochemical expression of p21 protein in consecutive paraffin sections from 131 transitional cell carcinomas (TCCs) and related it to p53 protein expression, clinicopathologic parameters, proliferative fraction, and survival. Positivity was displayed in 45% of cases, among which one fourth was accompanied by p53 accumulation.
p21
expression was statistically related to advanced T category. No association was shown between
p21
and p53 or proliferation rate. Low grade invasive TCCs tended to be more often
p21
positive than high grade invasive TCCs. Most superficial tumors displayed neither
p21
nor p53 expression, whereas the combined phenotypes p53/p21+ and p53+/
p21
- predominated among invasive tumors. P21 labeling index emerged by multivariate analysis as the single independent indicator of shortened overall (P = 0.0294) and disease-free (P = 0.0414) survival in superficial TCCs. Conversely, in invasive tumors, loss of
p21
expression was a predictor of shortened disease-free survival (P = 0.0234) and was associated with poor outcome when accompanied by p53 accumulation (P = 0.0033). In conclusion, our results indicate that
p21
activation occurs early in tumorigenesis, appears associated with invasiveness, and is capable of cell cycle control in TCCs mostly through p53-dependent pathways. Finally,
p21
expression, alone or in combination with p53 and irrespective of other clinicopathologic parameters, plays distinct roles in determining clinical outcome in superficial and invasive tumors, suggesting that urothelial
bladder cancer
represents two different diseases.
...
PMID:WAF1/p21 protein expression is an independent prognostic indicator in superficial and invasive bladder cancer. 1112 20
Adriamycin (ADM), widely used for systemic and local treatment of bladder tumors, triggers apoptosis in
bladder cancer
cells. Here we investigated the effect of ADM on cell cycle progression and expression of cell cycle regulating proteins in
bladder cancer
cell lines with various p53 and
p21
(WAF1/CIP1) status. Flowcytometric analysis was used to estimate the cell cycle distribution of T24, HT-1376, RT4, and SCaBER
bladder cancer
cell lines. Cell cycle regulating proteins were analyzed by Immunoblot. Treatment of RT4 cells, bearing wild type p53 and
p21
(WAF1/CIP1), with ADM induced expression of both proteins and cell cycle arrest, not in G1, as was anticipated, but in the G2 phase. Simultaneously, Retinoblastoma (Rb) protein expression was decreased. Expression of PCNA, which is a target gene of E2F, was not changed. The results suggest that even if the tumor cells bear wild type (wt) p53 and wt
p21
(WAF1/CIP1) and both proteins accumulate due to genotoxic stimuli, the cell cycle arrest might happen not in the G1 but in the G2 phase.
...
PMID:Adriamycin induced G2/M cell cycle arrest in transitional cell cancer cells with wt p53 and p21(WAF1/CIP1) genes. 1127 27
Sodium butyrate (NaBt), a physiologically occurring short-chain fatty acid, induces differentiation as well as apoptosis in numerous cell types, and this induction is partially regulated by Bcl-2 expression. The objectives of our study were to characterize the in vitro effects of NaBt and/or docetaxel on the growth, cell cycle and apoptosis of human
bladder cancer
cells, and to determine whether tumor growth in vivo is inhibited by isobutyramide, an orally bioavailable Bt analogue, and/or docetaxel by using Bcl-2-transfected human
bladder cancer
cell line KoTCC-1/BH and control vector only-transfected cell line KoTCC-1/C. NaBt caused a decrease in growth of both KoTCC-1/C and KoTCC-1/BH cells, however, its growth inhibitory effect was significantly greater in KoTCC-1/C cells. One mM NaBt resulted in G1 cell cycle arrest, accompanied by up-regulation of
p21
(waf1/cip1) and down-regulation of cyclin D1 in KoTCC-1/C cells, whereas KoTCC-1/BH showed resistance to G1 cell cycle arrest. An amount of 5 mM NaBt induced apoptosis, accompanied by up-regulation of Bak in KoTCC-1/C cells but failed to induce apoptosis in KoTCC-1/BH cells despite substantial down-regulation of Bcl-2. Oral administration of isobutyramide significantly reduced the KoTCC-1/C tumor volume compared with the KoTCC-1/BH tumor volume in nude mice. Furthermore, docetaxel induced Bcl-2 phosphorylation in KoTCC-1/BH cells and combined treatment with isobutyramide and docetaxel synergistically inhibited the growth of KoTCC-1/BH cells both in vitro and in vivo. These findings suggest that isobutyramide therapy could be a novel therapeutic strategy for patients with
bladder cancer
if docetaxel is combined according to the Bcl-2 expression status.
...
PMID:Overexpression of Bcl-2 regulates sodium butyrate- and/or docetaxel-induced apoptosis in human bladder cancer cells both in vitro and in vivo. 1139 17
The coxsackie and adenovirus receptor (CAR) is identified as a high-affinity receptor for adenovirus type 5. We observed that invasive
bladder cancer
specimens had significantly reduced CAR mRNA levels compared with superficial
bladder cancer
specimens, which suggests that CAR may play a role in the progression of
bladder cancer
. Elevated CAR expression in the T24 cell line (CAR-negative cells) increased its sensitivity to adenovirus infection and significantly inhibited its in vitro growth, accompanied by
p21
and hypophosphorylated retinoblastoma accumulation. Conversely, decreased CAR levels in both RT4 and 253J cell lines (CAR-positive cells) promoted their in vitro growth. To unveil the mechanism of action of CAR, we showed that the extracellular domain of CAR facilitated intercellular adhesion. Furthermore, interrupting intercellular adhesion of CAR by a specific antibody alleviates the growth-inhibitory effect of CAR. We also demonstrated that both the transmembrane and intracellular domains of CAR were critical for its growth-inhibitory activity. These data indicate that the cell-cell contact initiated by membrane-bound CAR can elicit a negative signal cascade to modulate cell cycle regulators inside the nucleus of
bladder cancer
cells. Therefore, the presence of CAR cannot only facilitate viral uptake of adenovirus but also inhibit cell growth. These results can be integrated to formulate a new strategy for
bladder cancer
therapy.
...
PMID:The mechanism of the growth-inhibitory effect of coxsackie and adenovirus receptor (CAR) on human bladder cancer: a functional analysis of car protein structure. 1152 59
pT1 G3 bladder carcinomas are heterogeneous with respect to tumor recurrence and progression. Whereas some urologists treat these carcinomas by repeated transurethral resections often followed by intravesical chemotherapy or BCG instillation, others recommend cystectomy after tumor recurrence or early cystectomy after the initial diagnosis. Our goal was to determine the prognostic value of p53,
p21
/WAF1, Bcl-2, Bax, Bak, and Ki-67 immunoreactivity in these tumors. There were 30 patients with a new histopathological diagnosis of pT1 G3 urothelial carcinoma based on a transurethral resection specimen. Representative sections of these specimens were examined for the above markers. All patients were followed up regularly and were classified as being tumor free or having tumor recurrence or progression. The mean follow-up period was 43 months (range: 8-102 months). Twenty-five patients underwent radical cystectomy and 7 of these (28%) suffered from tumor progression and died of
bladder cancer
. In 5 patients, surgery was limited to a transurethral resection and 4 of these patients developed superficial tumor recurrence. There was a significant difference in tumor-free survival between patients with p53-immunoreactive (mean: 30 months) and p53-negative tumors (mean: 82 months; p = 0.0341). Bcl-2 positivity was also associated with decreased tumor-free survival (p = 0.043). The other markers had no significant prognostic impact. We conclude that p53 and Bcl-2 immunoreactivity labels the most aggressive pT1 G3 bladder carcinomas.
...
PMID:Prognostic value of p53, p21/WAF1, Bcl-2, Bax, Bak and Ki-67 immunoreactivity in pT1 G3 urothelial bladder carcinomas. 1155 64
This study was designed to define the potential clinical relevance of identifying alterations affecting p53 pathway in
bladder cancer
and to test a new, low-cost, high-throughput, and array-based TP53 sequencing technology. Tumor samples from 140 evaluable patients with
bladder cancer
were analyzed with two methods to detect TP53 gene mutations, including single-stranded conformational polymorphism followed by direct sequencing and an oligonucleotide array-based sequencing method. Immunohistochemistry was used to assess patterns of expression of p53,
p21
/WAF1, and mdm2. Median follow-up time was 27.6 months. Results from the above analyses were correlated with clinicopathological parameters and outcome. Combining the mutation-detection assays, 79 cases (56.4%) were found to harbor TP53 gene mutations. Direct sequencing identified 66 point mutations and five frameshift mutations. The p53 oligonucleotide array detected 65 point mutations and four splice site mutations in different exons but missed all five frameshift mutations. p53 nuclear overexpression was observed in 71 cases (50.7%), lack of
p21
nuclear expression was found in 81 cases (57.9%), and mdm2 nuclear overexpression was seen in 64 cases (45.7%). In multivariate analysis, 17 patients (12.1%) had an altered p53 pathway, defined by the detection of mutant TP53 and/or p53 nuclear overexpression, loss of
p21
nuclear expression, and mdm2 nuclear overexpression, and exhibited the worst clinical outcome in the observation period (P = 0.015), and it appears to be a significant prognostic factor associated with patient survival.
...
PMID:Impact of alterations affecting the p53 pathway in bladder cancer on clinical outcome, assessed by conventional and array-based methods. 1180 55
Cyclin D1 contributes to regulate G1 progression by forming a complex with different cyclin-dependent kinases. It has oncogenic properties and is frequently overexpressed in several human tumor types. In our study, expression of cyclin D1 and Ki67, a proliferation marker, was evaluated by immunohistochemistry in human papillary superficial (pTa-pT1) bladder cancers and was correlated with p27(Kip1),
p21
(Waf1) and c-erbB-2 expression, with p53 gene status and protein expression, ploidy and cancer progression. Cyclin D1 expression was neither associated with tumor stage nor with tumor grade but high cyclin D1 expression (> or =25% positive nuclei) was significantly associated with p53 gene mutation (p = 0.012), low
p21
(Waf1) (p = 0.015) and high p27(Kip1) (p = 0.016) protein expression. Ki67 expression was not associated with tumor stage but a high proliferation index (> or =10% positive nuclei) was significantly associated with high tumor grade (p = 0.001) and with DNA aneuploidy (p = 0.005). There was no significant difference in proliferative activity between high and low cyclin D1 expressor tumors. Patients whose tumors showed high expression of cyclin D1 displayed a significantly longer disease-free survival (p < 0.001 by log-rank test). Increased Ki67 expression was significantly associated with shorter disease-free survival (p = 0.003). Both cyclin D1 (p = 0.027; RR = 1.898) and Ki67 (p = 0.047; RR = 1.932) protein expressions were independent predictors of reduced disease-free survival on a multivariate analysis that also included p27(Kip1) expression and tumor stage. The simultaneous presence of low cyclin D1, low p27(Kip1) and high Ki67 expression defined a "high-risk" group of patients who displayed a significantly increased risk of recurrence (p < 0.0001). These results suggest that evaluation of cell cycle-associated markers can help to identify high-risk patients and may affect the management of patients with papillary superficial
bladder cancer
.
...
PMID:Cyclin D1 expression in papillary superficial bladder cancer: its association with other cell cycle-associated proteins, cell proliferation and clinical outcome. 1180 96
Ras oncogenes are considered to play a key role in the carcinogenesis and progression of human
bladder cancer
. The oncogenes code for the Ras
p21
proteins, which localize in the internal part of the cell membrane and act as molecular switches to mediate downstream signaling from a variety of extracellular stimuli. Activation of Ras proteins induces the constitutive activation of downstream kinase cascades, which results in continuous mitogenic signaling and transformation of immortalized cells in human
bladder cancer
. Therefore inactivation of the activated Ras function might be effective for the development of a novel treatment strategy against human
bladder cancer
. Recently several ways to suppress Ras activities, including inhibitors of Ras signal transduction and a ras suppressor mutant, have been reported. Here we review the current concepts of the basic mechanisms of the intracellular Ras signaling pathway and ras activation in the carcinogenesis and progression of human
bladder cancer
and discuss clinical potentials of their therapeutic interventions.
...
PMID:Ras signal transduction in carcinogenesis and progression of bladder cancer: molecular target for treatment? 1238 14
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>