RB1 and neoplasm: Several studies support a role for SF-1 as a suppressor of ovarian cancer: i) ectopic expression of SF-1 inhibits rat ovarian epithelial cell proliferation, causing cell cycle arrest and promoting apoptosis (7); ii) the tumor suppressor Rb1 synergizes with steroid receptor co-activator-2 (SRC-2) to enhance the activity of SF-1 as well as nuclear receptors ERα and ERβ (8); Rb1 may thus promote the transcription of target genes linked to cell differentiation; iii) SF-1 promotes differentiation of human and rat granulosa cells associated with the developing oocytes (9).