Ovarian Clear Cell Carcinomas: RHO GTPases May Explain Their Singular Biologic Behavior
B Canet, ML Romero, I Espinosa, J Pena, J Prat. Hospital de la Santa Creu i Sant Pau. Autonomous University of Barcelona, Barcelona, Spain
Background: The biologic behavior of clear cell carcinomas (CCCs) of the ovary differs from that of high-grade serous carcinomas(HGSCs). Although the former appear confined to the ovary (stage I) more often than the latter, their overall prognosis is poor and characterized by recurrence, metastasis, and poor response to chemotherapy. The RHO GTPase family of proteins is involved in tumor progression through regulation of the cytoskeleton.
Design: The expression of several RHO family genes, including RHOA, RHOC, CDC42, and ARHGDIG was studied by Real-Time PCR in 12 CCCs and 31 HGSCs.
Results: Four CCCs (4/12; 33%) were found at stage I. Postoperatively, all patients were treated with taxane and cisplatinum or carboplatinum.Of the 7 patients with advanced stage tumors and follow-up available, 3 died of tumor, 1 is alive with disease, and 3 are alive without evidence of disease after a short interval (mean 2.1 years). ARHGDIG (Rho GDP dissociation inhibitor gamma) mRNA expression was higher in CCCs than HGSCs (P=0.06). In contrast, CDC42 mRNA levels were lower in CCCs than HGSCs (P=0.01). Stage I CCCs were associated with high ARHGDIG mRNA expression (P=0.08). In advanced stage tumors (stages II, III, and IV), ARHGDIG expression tended to be higher in patients who responded to chemotherapy (median ΔΔCt: 30 vs. 3; P=0.1).
Conclusions: ARHGDIG expression contributes to explain the clinicopathological features of CCCs; that is, earlier stage at diagnosis compared with serous carcinomas and variable response to chemotherapy.
Category: Gynecologic & Obstetrics
Wednesday, March 24, 2010 1:00 PM
Poster Session VI # 156, Wednesday Afternoon