Strong expression of steroid sulfatase in human cumulus cells in patients with endometriosis.

Objective To investigate the localization and expression of steroid sulfatase (STS) in cumulus cells obtained from subjects with and without endometriosis. Design Case-control study. Setting In vitro fertilization program at the Showa University School of Medicine. Patient(s) Cumulus cells (142 samples) were obtained from 49 patients for whom IVF was indicated. Some of these samples were taken from cases complicated by endometriosis (35 samples), polycystic ovary syndrome (PCOS; 16 samples), or latent hyperprolactinemia (16 samples). Intervention(s) Immunohistochemical staining for STS. Measurement of STS mRNA expression by real-time polymerase chain reaction (PCR). Main Outcome Measure(s) Expression of STS mRNA and localization of STS. Result(s) Steroid sulfatase was localized in the cytoplasm of the cumulus cells, and expression of STS mRNA was observed. The expression level of STS mRNA from patients with endometriosis was significantly higher (11.8-fold) than that of patients without endometriosis. Conclusion(s) These results suggest a local steroidal regulation mechanism in cumulus cells. Although the physiological role of STS in cumulus cells remains unclear, STS may be involved in the quality of eggs in patients with endometriosis.