Expression of p53, p21WAF1/CIP1, p16INK4A and Ki-67 proteins in serous ovarian tumors.

AIM: The analysis of p53, p21(WAF1/CIP1), p16(INK4A) and Ki-67 expression in serous ovarian carcinomas of different grade.

MATERIALS AND METHODS: In total, 43 ovarian adenocarcinomas and 8 non-altered ovarian epithelial tissues were immunohistochemically investigated for expression of Ki-67, p53, p21(WAF1/CIP1) and p16(INK4A).

RESULTS: It has been shown that expression of Ki-67, p53, p21(WAF1/CIP1) and p16(INK4A) in non-altered ovarian epithelial tissue is absent. Serous ovarian carcinomas are characterized by high proliferative activity (PI Ki-67 = 30.0 +/- 0.3%), p53 and p16(INK4A) overexpression (LI is 40.3 +/- 0.3% and 31.1 +/- 0.6% respectively) and low expression of p21(WAF1/CIP1) (LI = 6.8 +/- 0.3%). The association between expression of these markers and ovarian tumor grade was defined: the maximal level of Ki-67, p53 and p16/(INK4A) and minimal of p21(WAF1/CIP1) expression were observed in G3 tumors. So, low p21(WAF1/CIP1) expression (LI < 7.0%) combined with p16(INK4A) overexpression is considered to be the factor for a poor prognosis in serous ovarian cancer.

CONCLUSIONS: The present study has indicated that biomolecular markers of cell proliferation along with traditional clinical and morphologic characteristics can be used for differential diagnostics of ovarian tumors.