IMMUNOHISTOCHEMICAL EXPRESSION OF MDM2 AND P21(WAF1) IN INVASIVE CERVICAL-CANCER - CORRELATION WITH P53 PROTEIN AND HIGH-RISK HPV INFECTION

Aim-To investigate the immunocytochemical staining pattern of mdm2 and p21(WAF1) proteins in invasive cervical cancer and to determine its r elation with the expression of p53 and with the high risk HPV infectio n. Methods-Immunocytochemistry for p53, mdm2, and p21(WAF1) was perfor med in 31 paraffin embedded sections of invasive cervical cancer. The results were assessed by image analysis, evaluating for each protein t he optical density of the immunostained area, scored as percentage of the total nuclear area. The presence of high risk human papillomavirus (HPV) infection was detected by using the polymerase chain reaction. Results-Immunostaining for both mdm2 and p21(WAF1) was correlated with p53 expression; however, the correlation between p53 and mdm2 (R = 0. 49; p < 0.01) was more significant than between p53 and p21(WAFl) (R = 0.31; p < 0.05); the less stringent correlation between p53 and p21(W AF1) might reflect the p53 independent mechanisms of p21(WAF1) inducti on. Similar average levels of p53, mdm2, and p21(WAF1) immunostaining were found in the presence or absence of high risk HPV-DNA, without si gnificant differences between the two groups. Conclusions-These data s uggest that mdm2 and p21(WAF1) proteins are expressed in invasive cerv ical cancer and that their immunocytochemical staining pattern is not abrogated by the presence of high risk HPV genomic sequences.