Betaglycan blocks metastatic behaviors in human granulosa cell tumors by suppressing NFκB-mediated induction of MMP2.

Metastatic ovarian granulosa cell tumors (GCT) exhibit loss of betaglycan. Here we test the hypothesis that betaglycan blocks GCT metastasis by suppressing NFκB/TGFβ2-induced matrix metalloprotinease-2 (MMP2). Human GCT and a human GCT cell model demonstrated prominent MMP2 expression, which was dependent on NFκB activity and stimulated by TGFβ2 in an NFκB-dependent manner. Betaglycan suppressed both basal and TGFβ2-induced MMP2 expression and countered metastatic behaviors of GCT cells in non-adherent spheroid culture and in vivo xenograft models of metastasis. These data suggest that NFκB/TGFβ2 promotes, and betaglycan impedes, the early stages of GCT metastasis, when tumor cells first invade the peritoneum.