Clinical Significance of Expression of PGP 9.5 in Eutopic Endometrium of Patients with Endometriosis-Related Chronic Pelvic Pain

Objective To study the expression of protein gene product 9.5(PGP 9.5)in the functional layer of eutopic endometrium and its relation to chronic pelvic pain(CPP)in patients with endometriosis(EMs),and to investigate the role of PGP 9.5expression and the curative efficacy of gonadotrophin-releasing hormone agonist(GnRHa)in EMs-related CPP.Methods The expression of PGP 9.5in the functional layer of eutopic endometrium was detected by immunohistochemistry in 40 patients treated with surgery for EMs(EMs group)and 40 women of childbearing age(control group).The degree of CPP and stage of endometriosis were evaluated by using visual analogue scale(VAS)and revised American Fertility Society(rAFS)classification system,respectively.The correlations of VAS and rAFS scores with PGP 9.5expression were analyzed by using Spearman method.In addition,the expression of PGP 9.5was detected in EMs patients before and after treatment with GnRHa.Results The expression of PGP 9.5in the functional layer of eutopic endometrium was 10.48±4.44 in EMs group.No PGP 9.5expression was found in control group.In patients with EMs-related CPP,PGP 9.5expression was positively correlated with VAS score(r=0.833,P0.01),but was not correlated with rAFS score(r=-0.094,P0.05).After operation,the treatment with GnRHa significantly reduced PGP 9.5expression and VAS score in patients with EMs(P0.01).Conclusion The PGP 9.5is expressed specifically in the functional layer of eutopic endometrium,suggesting that PGP 9.5may be a new biomarker for early diagnosis of EMs.The high expression of PGP 9.5in eutopic endometrium is positively correlated with CPP,but is not correlated with rAFS in EMs patients.The GnRHa can relieve the EMs-related CPP through reducing the density of endometrial nerve fibers.