{"paper_id":"497ae8a1-4f84-4790-b7f8-a42c820bfe20","body_text":"Abstract\nObjective\nThe aim of this study was to examine the expression of G protein-coupled estrogen receptor (GPER) and Gankyrin in ovarian endometriosis, analyze their clinicopathological significance, and investigate their correlation.\nMethods\nQuantitative real-time polymerase chain reaction and Western blot were performed to testify mRNA and protein expression of GPER and Gankyrin in ovarian endometriosis. Immunohistochemical staining (streptavidin–peroxidase method) was conducted to determine the expression and distribution of GPER and Gankyrin protein in matched ectopic and eutopic endometrium of endometriosis and normal endometrium. We also investigated their associations with rASRM stages and the correlation between the two proteins.\nResults\nGPER and Gankyrin were found overexpressed in ectopic endometrium of endometriosis compared with either its eutopic counterpart or endometrium from normal patients. The immunohistochemical analysis also revealed that higher expression was observed in eutopic endometrium with or without endometriosis during proliferative phase in comparison to secretory phase. These two proteins were positively correlated with the stages of endometriosis. Moreover, a significant positive correlation was found between GPER and Gankyrin both in ectopic and eutopic endometrium of the ovarian endometriosis.\nConclusion\nGPER and Gankyrin might be implicated in the hormonal regulation of endometriosis and be associated with the severity of endometriosis. In addition, GPER and Gankyrin were found to be positively correlated, which could possibly serve as novel therapeutic targets for this disease.\nSimilar content being viewed by others\nReferences\nVercellini P, Viganò P, Somigliana E, Fedele L (2014) Endometriosis: pathogenesis and treatment. 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