A novel non-invasive molecular biomarker in ovarian endometriosis: estrogen-related receptor α

Purpose This study aimed to explore whether estrogen-related receptors alpha (ERR alpha) can prognosticate the occurrence and development of ovarian endometriosis (EMs) as a non-invasive biomarker. Methods The ectopic and its' correspond eutopic endometria from 47 patients with ovarian EMs and the control normal endometria from 32 cases were collected and detected the mRNA expression of ERR alpha by RT-qPCR. The serum protein of ERR alpha were tested by ELISA. The menstrual cycle, ovarian cyst sizes, relative clinical tumour markers, such as CA125, CA19-9 and HE-4, and other demographic data were also involved into analysis in these patients by SPSS 22.0 (IBM, Chicago, IL, USA). Results The ERR alpha mRNA expression in ectopic endometria were significantly lower than it in eutopic endometria (P < 0.05) and the normal endometria (P < 0.05). Similarly, the serum ERR alpha levels in patients with EMs were significantly lower than it in control group (P < 0.01). Moreover, the serum ERR alpha levels were decreasing with the increasing of the pathological stages and ovarian cyst sizes. While, the serum CA125, CA19-9, CA125/ERR alpha ratio and CA19-9/ERR alpha ratio in the study group were significantly higher than those in the control group (allP < 0.01). Conclusion The expression of ERR alpha is correlated with the development of ovarian EMs pathological stages and ovarian cyst sizes and can be used as a novel and non-invasive biomarker for evaluating the progression of ovarian EMs.