Investigation of the relationship between DNA methylation dynamics and ten-eleven translocation genes and enzymes in endometriosis tissue

Endometriosis is the development of endometrial tissue outside the uterine cavity. The etiology of the disease is still unknown. Many recent studies have shown the relationship between epigenetic modifications and diseases. DNA methylation and demethylation of epigenetic alteration mechanisms have been the most researched subject. However, immunohistochemical expressions of TET enzymes in endometriosis has not been investigated. The aim of our study was to investigate the expression of Ten-eleven translocation (TET) genes and enzymes that catalyze DNA demethylation in endometriotic tissue implanted in ovarian tissue. The project compared endometrial tissue obtained from 15 healthy individuals and endometrioma tissue from 15 patients with endometriosis. Tissue samples collected at mid-follicular phase were examined using TET1, TET2 and TET3 primary antibodies, and expression levels between the control and experimental groups were studied by immunohistochemical labeling and RT-PCR. All the obtained results were statistically analyzed. While no significant difference was found between the TET1 and TET3 immunoreactivities of the samples collected at the middle proliferative stage, TET2 immunolabeling in the endometrial stroma was significantly decreased in the endometriosis group. There was no significant difference in mRNA expression between the groups. In view of our results, the TET enzyme family was found to be expressed in the endometrium, and it was suggested that low TET2 expression in endometriosis might be associated with progesterone resistance.