Objective: To analyze the expression of the AP-2gamma transcription factor in ovarian borderline tumors, early-stage ovarian carcinoma and advanced-stage ovarian carcinoma, and to evaluate its prognostic role in advanced-stage tumors.
Methods: Sections from 14 normal ovaries, 75 borderline tumors, 22 FIGO stage I invasive ovarian carcinomas, and 306 advanced-stage (FIGO stages II-IV) ovarian carcinomas (42 primary tumors, 62 solid metastases, 202 effusions) were evaluated for expression of the transcription factor AP-2gamma using immunohistochemistry. Sixty-three effusions and two cell lines (SKOV-3 and OVCAR-3) were additionally studied using immunoblotting. The prognostic role of AP-2gamma in advanced-stage carcinomas was analyzed.
Results: AP-2gamma was detected in the nucleus of tumor cells in 28/75 (37%) borderline tumors, 13/22 (59%) FIGO stage I carcinomas, and 255/306 (83%) advanced-stage carcinomas (P < 0.001, Chi-square test). Benign ovaries were uniformly negative. Expression was largely limited to carcinoma cells in effusions. Solid lesions and effusions from advanced-stage carcinomas showed comparable expression. Immunoblotting showed AP-2gamma expression in 59/61 effusions and both cell lines. AP-2gamma expression did not correlate with survival.
Conclusions: AP-2gamma expression is upregulated in advanced-stage ovarian carcinoma compared to early-stage carcinomas, borderline tumors, and the ovarian surface epithelium, and AP-2gamma is specifically localized to cancer cells in effusions, suggesting a role in tumor progression. The lack of predictive value for this transcription factor in advanced-stage disease may be related to its frequent expression.