Expression of p21(WAF1/CIP1) and p53 proteins in gastric carcinoma: its relationships with cell proliferation activity and prognosis

The expressions of p21(WAF1/CIP1), p53 proteins, and Ki-67 antigen were inv estigated immunohistochemic ally in 190 primary gastric carcinomas. Of the 190 tumors, 40.5% positively expressed p21(WAF1/CIP1) and 42.1% positively expressed p53. The expression of p21(WAF1/CIP1) was significantly associate d with clinicopathological factors including gender, tumor size, status of lymph node, and clinicopathological stage (P < 0.05 for all), but p21(WAF1/ CIP1) expression showed no clear correlation with Ki-67 labeling index. The mean Ki-67 labeling index was significantly higher in p53-positive cases t han p53-negative, cases (P < 0.0001). However, among the clinicopathologica l factors examined, expression of p53 correlated only with age. Univariate and multivariate survival analyses revealed that clinicopathological stage (P < 0.001) and expression status of p21(WAF1/CIP1) (P < 0.05) were indepen dent prognostic factors. Neither the expression status of p53 nor the Ki-67 labeling index, however, influenced the prognosis of patients with gastric cancer. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.