Expression of bcl-2 and p53 Protein, and Apoptosis in Transitional Cell Carcinoma of the Bladder

Chung, Myoung Ja; Kim, Sang Su; Choi, Ho Yeul

Abstract

This study examined the expression of the bcl-2 protein in 59 cases of transitional cell carcinomas (TCCs) of the bladder and evaluated the relationship of bcl-2 and p53 with apoptosis. The cases were divided into 41 low-grade TCCs, 18 high-grade TCCs, 32 superficial TCCs, and 27 invasive TCCs. p53 and bcl-2 protein were detected by the immunohistochemical method and apoptosis was analysed by using hematoxylin-eosin stained slide. The results were as follows: bcl-2 protein was detected in 8 (14%) TCCs and all of these cases were low grade TCCs. Expression of bcl-2 protein was not correlated with clinical stage. There was no correlation between bcl-2 and p53 protein. According to the immunohistochemical results of bcl-2 and p53 protein, the cases were divided 4 groups. Apoptotic index (AI) was higher in p53 positive/ bcl-2 negative group than other groups but the significance was recognized only between p53 positive/bcl-2 negative group and p53 negative/bcl-2 negative group (p<0.05). p53 protein was detected in 20 (36%) TCCs and its expression was correlated positively with histologic grade and clinical stage (p<0.05). AI correlated positively with histologic grade and clinical stage (p<0.01). These data indicate that overexpression of bcl-2 protein is rare in TCC of the bladder and associated with low grade TCCs. Overexpression of p53 is associated with the tumor progression in the TCCs. AI correlates with p53 positivity but does not correlate with bcl-2 positivity.