Shared biological features between ovarian cancer and endometriosis based on co-expression networks analysis

Abstract

Background: Endometriosis is a gynecologic disease common among younger females, impacts adversely the quality of life, and results in infertility. The evidence demonstrates that patients with endometriosis have a higher risk of developing ovarian cancer. Due to this similarity, we aimed to identify common molecular markers between ovarian cancer and endometriosis. Methods: We used publicly available microarray data (GSE9899) including ovarian tumor samples and alongside normal controls, common differentially expressed genes (DEGs) were identified in ovarian samples compared to controls. We constructed a co-expression network based on ovarian cancer and then extracted the hub genes. We validated the similarities between ovarian cancer and endometriosis by examining the expression of hub genes in endometriosis patients referred to Iranian Rasoul Akram Hospital. Results: In total 1000 DEGs were identified in grade 2 and grade 3 of ovarian cancer. We identified 34 co-expression modules in grade 3 ovarian cancer and 31 in grade 2. Modules were mostly enriched in inflammatory response and plasma membrane-bounded cell projection, mostly. To validate the comorbidity of ovarian cancer and endometriosis, we examined the expression of six significant hubs (resulting in an ovarian cancer co-expression network) in women with endometriosis. Conclusion: Our results suggest that patients with endometriosis have a higher risk of developing ovarian cancer. These findings will improve the diagnosis of ovarian cancer in endometriosis patients. More research is required to find the exact mechanism of hub genes affecting the development of ovarian cancer.