Local Expression and Significance of Steroid Metabolizing Enzymes in Endometriosis

Objective:To investigate the estrogen metabolism in matched ectopic and eutopic tissue from patients with endometriosis and in normal endometrium.Methods:P450 aromatase(P450A) mRNA and protein、17β-Hydroxysteroid dehydrogenase 2(17β-HSDⅡ) mRNA expression in eutopic and ectopic endometrium of patients with endometriosis(n= 67) and in normal endometrium from control group(n=35) were detected by reverse transcription-polymerase chain reaction and immunohistochemistry.Results:①P450AmRNA was not expressed in control group,but 17β-HSDⅡ mRNA was detected weakly at late proliferative phase and gradually increased to peak in the late secretory phase.② P450AmRNA and protein were weakly expressed in eutopic tissue of endometriosis,while the expression of 17β-HSDⅡ mRNA in eutopic tissue was similar to that of control group,except its intensity was lower than that of normal control.③ All ectopic tissue in 67 cases of endometriosis presented P450AmRNA and protein expression,but the expression of 17β-HSDⅡ mRNA was absent.Conclusions:The ectopic endometrium of endometriosis can produce estrogen by itself,but the metabolism is defecit,so the local consistant estrogen concentration might be the reason of growth of ectopic endometrium.