Analysis of the Differential Expression of Genes Involved in Pathways of Cell Proliferation, Differentiation and Inflammatory Responses in the Eutopic Endometrium of Patients with and Without Endometriosis

An observational cross-sectional study was conducted in a university hospital to evaluate eutopic endometria from women who underwent a laparoscopy, comprising 20 patients with endometriosis and 25 without the disease (control group). The differential gene expression was analyzed between the groups by RT-qPCR for the genes FOS, FOSB, JUNB, and EGR1, which are involved in common pathways regulating cell differentiation and proliferation and the early response to inflammatory insults. In the endometriosis group, the mean patient’s age was 36.4 years, and 34.4 years in the control group. The groups were homogeneous with respect to clinical variables, except for the parity, which showed a higher frequency of nulliparous women among endometriosis patients. Most of the included patients in both groups were on hormonal medications. There was no difference between the groups in the expression of EGR1 (p = 0.9231), FOS (p = 0.1261), or FOSB (p = 0.8249). Concerning JUNB, we observed a higher expression in the control group in comparison with endometriosis patients (p = 0.0417). These results may reflect the paradoxical role of JUNB in modulating proliferation and apoptosis and highlight possible biological variability among different populations. Finally, analyzing only the eutopic endometrium may not shed light on the complexity of the endometriosis pathophysiology, since the endometrium undergoes critical modifications when present outside the uterus and in the context of already established disease. Future studies should aim to better understand the peritoneal microenvironment, prioritizing broader evaluations of post-transcriptional factors.