Analysis of mRNA expression and DNA methylation level of RAC1 gene encoding focal adhesion molecule in endometrial and peritoneal endometriosis

Abstract

Focal adhesion molecules involve in cellular migration, attachment, and play a role in endometriosis pathomechanisms. Recent studies showed that the expression of RAC1, a gene encoded focal adhesion molecule, was predominantly found in endometriosis. As gene expression may be regulated by DNA methylation. Therefore, this study aimed to analyze promoter methylation level of RAC1 gene and mRNA expression in endometrial and peritoneal endometriosis tissues. This study using 20 endometrial and 9 peritoneal tissues from the same patients and 20 normal endometrial. The DNA and RNA from samples were isolated, DNA was converted using sodium bisulfite and amplified using Methyl Specific Polymerase Chain Reaction (MSP) method. The methylation level was determined by the intensity measurement of the bands that arose in gel electrophoresis using ImageJ software, whereas mRNA expression level was measured by Reverse Transcription-quantitative PCR (RT-qPCR) method. The mRNA expression level of RAC1 gene in peritoneal endometriosis increased compared to normal endometrium, as well as compared to endometrial endometriosis, but there was no significant difference in endometrial endometriosis compared to normal. Promoter hypermethylation level of RAC1 gene in peritoneal endometriosis was significantly different compared to normal endometrium, however not significant to endometrial endometriosis. Methylation level of its gene in endometrial endometriosis shown no significant difference compared to normal. There was association between promoter hypermethylation level and its mRNA expression in endometrial endometriosis (R= 0.014; p=0.952). The elevation of mRNA expression of RAC1 gene plays a role in endometrial cell migration to peritoneum, and associated with promoter hypermethylation level of its gene.