Oestrogen receptors and small nuclear ring finger protein 4 (RNF4) in malignant ovarian germ cell tumours

The peak incidence of malignant ovarian germ cell tumours occurs soon after puberty. Thus, gonadal steroids may play a role in their development. Oestrogen receptors (ER alpha and ER beta) and their co-regulators, including small nuclear ring finger protein 4 (SNURF/RNF4) mediate oestrogen actions. While ER beta and SNURF are down-regulated in testicular germ cell tumours, their role in the ovarian germ cell tumours remains unknown. We herein studied the different subtypes of malignant ovarian germ cell tumours, and found that they all express ER alpha, ER beta, and SNURF. Stimulation with oestradiol (E2), ER alpha, ER beta and SNURF significantly up-regulated mRNA expression in the human germinoma derived NCC-IT cells. Further, the effects of E2 were counteracted by an anti-oestrogen (ICI 182,780). Neither E2 nor ICI 182,780 had an effect on the proliferation of NCC-IT cells as assessed by flow cytometric analysis. our results suggest that oestrogen signalling has a role in malignant ovarian germ cell tumours. (C) 2009 Elsevier Ireland Ltd. All rights reserved.