The Roles of P53, Rb and Ki-67 LI on Bladder Tumor

Lee, Hyung Lae; Kim, Tong Wook; Lee, Sang Cheol; Kim, Yong Tae; Kim, Wun Jae

Abstract

PURPOSE: This study was performed to evaluate whether the overexpression of p53 and Ki-67, and loss or overexpression of Rb were associated with clinical parameters of bladder tumor.
MATERIALS AND METHODS
Fifty-two archival tumor specimens from transitional cell carcinoma of the urinary bladder in 42 male and 10 female patients ranging from 30 to 83 years old (mean age : 63.5 years old) were investigated for the expression of mutant p53, Rb and Ki-67 immunohistochemically. They were divided into 36 superficial and 16 invasive bladder tumors, and grade I in 10, II in 25 and III in 17.
RESULTS
p53 positivity and Ki-67 LI were significantly associated with tumor stage and grade(p<0.05 in each), but not with tumor recurrence. Loss of Rb gene expression or Rb overexpression was only correlated with stage. All specimens with p53 positivity and overexpression or loss of Rb protein simultaneously expressed higher Ki-67 compared to other bladder tumors.
CONCLUSIONS
p53 positivity, loss or overexpression of Rb and the level of Ki-67 LI were significantly correlated with tumor stage and grade, but not with bladder tumor recurrence. Also, correlations existed among them, especially p53 positivity was tightly connected with Ki-67 LI(r=0.778) in linear regression analysis. These results suggest that changes of p53 and Rb expression may have an important role in aggressiveness of human bladder tumor.