BMP-6 and SMAD4 gene expression are altered in the cumulus cells from women with endometriosis-associated infertility.

INTRODUCTION Oocyte competence and quality depend on communication between the oocyte and the cumulus and theca cells. In the preantral phase, the members of the transforming growth factor β (TGF-β) superfamily are responsible for this communication and playing an important role in folliculogenesis. Moreover, TGF-β superfamily are related to endometriosis (overexpression in the ectopic endometrium); however, few studies have explored these proteins as influencing fertility in this disease. Considering endometriosis related-infertility and to better understand the role of the TGF-β superfamily members in the antral phase in patients with endometriosis, this research investigated the gene expression of the ligands: AMH, BMP-6, GDF-9, INHA, INHBB and TGFβ3; receptors: AMHR2, BMPR2 and TGFβR3, and intracellular signaling: SMAD3 and SMAD4. MATERIAL AND METHODS The gene expression of the AMH, BMP-6, GDF-9, INHA, INHBB, TGFβ3, AMHR2, BMPR2, TGFβR3, SMAD3 and SMAD4 in cumulus cells were investigated through quantitative real-time PCR in a case-control study including infertile women with and without peritoneal endometriosis undergoing to IVF. RESULTS Age and outcomes of assisted reproduction were similar between the groups (P>0.05). However, patients with endometriosis showed reduced expression of BMP-6 and SMAD4 (P 0.05). CONCLUSIONS The reduced expression of BMP-6 and SMAD4 in patients with peritoneal endometriosis compared to the control group indicate that granulosa (cumulus) cell function could be altered in these patients.