The fallopian tube epithelium responds to ovarian activin in vivo and is correlated with disease-free survival (DFS). A) Immunostaining or phospho-Smad2/3 in the fallopian tube and ovary of control and superovulated mice. Scale bar = 50 µm at 20x and 10 µm at 100x. B) Oncomine analysis for ACVR1B, ACVR2A, TGFBR3, and INHA in serous tumors relative to normal ovary across 4 studies as indicated. Top: overexpressed genes (red); Bottom: under-expressed genes (blue). C) Percentage of tumors with altered INHBA, ACVR2A, and ACVR1B in TCGA using cBioPortal. D–G) Disease Free Survival (DFS) Kaplan-Meier plots from OvMark for ACVR1B (D) and ACVR2B (E), INHBA (F), and ACVR2 + INHBA (G) in serous ovarian cancer patients.