To determine whether the dysfunction of p53 caused either by mutation of the p53 gene itself or by binding to E6 protein of oncogenic HPVs is involved in the transitional cell carcinomas (TCCs) of the bladder, we analyzed 23 TCCs of the bladder.
Allelic losses in chromosome arm 17p, where the p53 gene resides, were found to be less frequent in squamous cell carcinomas (38%) than in invasive transitional cell carcinomas (60%).
Patients with transitional-cell carcinoma confirmed to the bladder that demonstrates nuclear p53 reactivity should be considered for protocols of adjuvant treatment.
The type and position of the mutations were not significantly different when compared with the spectra of p53 mutations previously reported for transitional cell carcinomas (TCCs).
Recent investigations have demonstrated alterations of the p53 tumor-suppressor gene in a considerable number of transitional-cell carcinoma (TCC) specimens.
One of these was a papillary nodular hyperplasia, indicating that p53 mutations can be present in low- as well as high-stage/grade bladder lesions. p53 mutations were not found in the exon 5-9 region in cells of any of eight bladder lesions induced by N-[4-(5-nitro-2-furyl)-2- thiazoly]formamide (FANFT), including five transitional cell carcinomas (TCCs), or either of two TCCs induced by N-methylnitrosourea.
Ninety-four patients with transitional cell carcinoma (TCC) of the renal pelvis and ureter, including dysplastic lesions, were studied for p53 and bcl-2 protein expression by immunohistochemistry.
To evaluate the expression of bcl-2 in transitional cell carcinoma (TCC) of the bladder; to compare bcl-2 expression with clinicopathological findings, p53 immunoreactivity, proliferating cell nuclear antigen (PCNA) expression, 2c deviation index (2cDI), 5c exceeding rate (5cER), and the mean nuclear area (MNA).
Allele loss in 29 surgically resected transitional cell carcinoma was examined by using the multiplex PCR with 7 and 1 microsatellite markers for 9p21 and TP53, respectively.
In addition, p53 mutations and loss of heterozygosity on various chromosomes have recently begun to shed light on the molecular pathways of transitional cell carcinomas of the bladder.
Alterations in the p53 gene are a predominant component in the development of transitional cell carcinoma (TCC), but the particular pathways distal to p53 alterations which contribute to urothelial transformation are not defined.
Overexpression of p53, normally secondary to gene mutation, in invasive uroepithelial neoplasms (transitional cell carcinoma) and a high percentage of transitional cell carcinoma in situ (CIS) has been described; however, the role of p53 before and after bacillus Calmette-Guérin (BCG) treatment of CIS needs to be defined.
Nuclear accumulations of p53 and mdm2 were examined immunohistochemically for 60 transitional cell carcinomas (primary lesions) and 13 accompanying (concomitant) carcinoma in situ lesions.
We immunohistochemically examined the expression of cyclin E and p53 proteins in 121 patients with transitional cell carcinoma (TCC) of the renal pelvis and ureter to determine their significance for tumour behaviour and patient prognosis.
Alterations of TP53 in microdissected transitional cell carcinoma of the human urinary bladder: high frequency of TP53 accumulation in the absence of detected mutations is associated with poor prognosis.
The p53 over expression was similar in all 3 tumor types with 82% for squamous cell carcinoma, and 73.7% for bilharzial and 81.3% for nonbilharzial transitional cell carcinoma (not significant, p = 0.5285).
The predictive value of p53 accumulation for tumor progression was further underlined by the finding that in a distinct group of 52 patients with progressive urothelial carcinoma 73% of the recurrent tumors displayed p53 accumulation.
Our results indicate that the frequency and pattern of p53 mutations are similar in transitional cell carcinomas of the bladder and the renal pelvis and do not reflect exposure to phenacetin and/or smoking.
These results suggest that the frequency of p53 nuclear overexpression in BBC is lower than that reported for conventional transitional cell carcinoma.
Thirteen of 28 patients (46%) with grade 2-3 multifocal transitional cell carcinoma (TCC) of the bladder were found to have p53 mutations using DNA sequence analysis.
To assess the value of p53 mutations in predicting the progression of superficial bladder cancer [transitional cell carcinoma (TCC)] and to define exactly when p53 mutations occur in the process of tumor progression, 80 consecutive bladder washings from 26 high-risk (indicated by quantitative karyometric analysis) superficial TCC patients were examined by single-strand conformation polymorphism.
We determined the roles of p53 status and the ratio of bcl-2/bax proteins for predicting the recurrence of bladder superficial transitional cell carcinoma that had been treated with intravesical chemotherapy after resection.
The presence and distribution of high-risk human papillomavirus (HPV) DNA type-16 and -18 or overexpression of the p53 protein were determined in 31 patients with renal pelvic and ureteral carcinoma in Saga prefecture of Japan, consisting of 28 transitional cell carcinomas (TCCs) and 3 squamous cell carcinomas (SCCs).
The objective of this study was to determine whether ploidy, MIB-1 proliferative activity, or p53 protein staining in inverted papilloma were predictive of urothelial carcinoma.