p21(WAF1/CIP1) protein expression in primary ovarian cancer

p21(WAF1/CIP1) protein is a cyclin-dependent kinase inhibitor, able to prev ent the CDK2/cyclin E induced retinoblastoma protein (pRB) phosphorylation, thus inhibiting cell cycle progression at G1 phase. p21(WAF1/CIP1) protein levels were examined in a series of 102 ovarian tissue samples including n ormal ovary, primary ovarian tumors, omental metastasis, recurrent disease and residual tumor after chemotherapy exposure, by Western blot analysis. T he association of p21(WAF1/CIP1) status with clinicopathological parameters and clinical outcome was also investigated. p21(WAF/CIP1) protein was dete ctable in 76 out of 102 (74%) ovarian tissue samples. We observed a signifi cant trend of p21 levels to gradually increase from normal ovarian tissues (median 0 a.u.) through primary ovarian cancers (median 0.19 a.u.), omental metastases (median 0.33 a.u.) and recurrence of disease (median 0.44 a.u.) (p=0.015). In the group of stage III-IV ovarian cancer patients, p21-posit ive cases showed a more favourable prognosis with respect to p21-negative c ases: the 3-year time to progression (TTP) rate was 58% for p21-positive co mpared with 33% of p21-negative cases (p=0.036). In conclusion, p21(WAF1/CI P1) expression levels Seem to be correlated with tumor status at the time o f diagnosis and can predict TTP in a selected group of patients.