Seyed Hamidreza Mirabutalebi - Genetics Department, Faculty of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Fatemeh Montazeri - Abortion Research Center, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Farzaneh Fesahat - Reproductive Immunology Research Center, Shahid Sadoughi University of Medical Science, Yazd, Iran.
Mohammad Hasan Sheikhha - Research and Clinical Center for Infertility, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.

Background: The study of microRNA expression can be effective in the diagnosing and treating different diseases. miR-135a is one of the most important micro-ribonucleic acids involved in endometriosis. Among the genes that become the target of the miR-135a and are subjected to changes in the endometrium of patients with endometriosis is HOXA10 gene which is expressed in the endometrium in response to steroid hormones. Objective: The aim of this study was to evaluate the expression of miR-135a and its relationship with the level of HOXA10 gene expression in both endometrial ectopic and eutopic tissues in patients with endometriosis compared to the control samples. Materials and Methods: In this prospective case-control study, both case-eutopic and case-ectopic tissue samples were obtained from 17 women with endometriosis and the eutopic endometrial tissue was sampled from 17 women with normal endometrium as the control group. The gene s expression of miR-135a and HOXA10 were investigated using quantitative reverse transcription PCR (q-RT PCR). Results: A significant decrease in the expression of HOXA10 gene was detected in case-eutopic during the luteal phase compared to the control samples (p=0.001), while in the case-ectopic, the expression of this gene was increased (p=0.681) compared to the control samples. In addition, the expression miR-135a in the luteal phase showed a remarkable increase in the case-eutopic endometrial tissue (p=0.026) as well as a significant decrease in the case-ectopic endometrial tissue compared to the control samples (p=0.008). Conclusion: Considering the inverse relations between the over-expression of miR-135a and the reduction of HOXA10, it seems that miR-135a may be applied as an endometrial diagnostic and therapeutic biomarker.

Endometriosis, Gene expression, Micro-ribonucleic acid, HOXA10, miR-135a