Objective: Endometriosis affects 5-15% of women in the general population and 40% of women seeking infertility evaluation. Its etiology and pathogenesis is controversial. Abnormalities of genes involved in the regulation of apoptosis have been thought to play a role in origin. Hence, we investigated the expression of pro-apoptotic and anti-apoptotic genes in eutopic endometrium from women with endometriosis and healthy controls in relation to disease occurrence and severity.
Study design: A prospective study in women undergoing laparoscopic surgery for pelvic pain was conducted. In total, 45 women (30 healthy controls and 15 patients) matched inclusion criteria. The mRNA expression of apoptotic genes (p53, Bcl-x(L,S) and Bax) from eutopic endometrium was detected by RT-PCR.
Results: A significant increase in expression of mRNA p53 (1.42 versus 1.02; p<0.05), and Bcl-x(S) (0.41 versus 0.19; p=0.0006) was found in women with endometriosis compared to healthy controls. Insignificantly increased expression was found for Bax (1.22 versus 1.15). The expression of anti-apoptotic Bcl-x(L) was unchanged (1.08 versus 1.07). The Bcl-x(L)/Bcl-x(S) ratio was twofold higher (5.63 versus 2.63) in controls. By stratifying patients by disease stage we have revealed an increased mRNA expression of apoptotic genes in patients with grades III-IV endometriosis compared to those with grades I-II. However, the difference was significant only for Bcl-x(S) expression (p<0.05).
Conclusions: Results suggest that an increased transcription of pro-apoptotic genes (p53 and Bcl-x(S)) in eutopic endometrium is significantly associated with endometriosis, which indicates dysregulation of apoptotic gene transcription associated with disease.