Phosphorylation Of Human Estrogen Receptor-Beta At Serine 105 Suppresses The Development Of Endometriosis

As one of the chronic gynecological disease,endometriosis?EMs?remains a global threat to the reproductive-aged women.It is characterized by the presence of endometrium-like tissue outside of the normal location--mainly on ovaries or pelvic peritoneum,commonly associated with chronic pelvic pain,infertility,dysmenorrhea and may lead to increased risk of ovarian cancer.There is much controversy surrounding the underdiagnosis of Endometriosis due to its non-specific symptoms.Disruption of hormonal balance has been implicated in endometriosis manifested as estrogen-dependent disease.Estradiol-17 beta?E2?is demonstrated to trigger nuclear signaling primarily via two estrogen receptors isoform?ERa and ER??.Our previous research has shown that ER? was significantly over-expressed in endometriosis tissues and it is a repressor of ERa transcriptional activity,which may prevent E2 from exerting its biologic function through ERa.Phosphorylation is the most common PTMs process to the activation of ER,phosphorylation of ER? at S105 inhibited breast cancer cell invasion and migration in vitro.However,no studies to date have detected the presence of phosphorylated ER? in endometriosis.Therefore,identifying the functional phosphorylation sites of ER? in endometriosis is imperative.Objective:In this paper,we try to embark on phosphorylation of ER? p-S105 and explore the different level of ER? p-S105 in endometriosis.The effect of ER? p-S105 on endometriosis was then investigated.Finally,in vitro studies with human endometriotic cells was performed to underline the roles of the phosphorylation of estrogen receptor beta serine 105.Method:Endometriosis tissues and normal endometrium was collected from endometriosis patients and endometriosis-free patients.Western blot and IHC were used to demonstrate the expressions of ER? p-S105 in ectopic endometrial tissues,eutopic endometrial tissues and normal endometrial tissues.Site-directed mutagenesis was used to prepare a phosphor-defective mutant S105A?ER?-S105A?and a phospho-mimetic mutant S105E?ER?-S 105E?.Primary eutopic endometrium glandular epithelial cells from endometriosis patients?eutopic EECs?were treated with IL-1?,or pre-incubated with LXA₄ before treat with IL-1?.The MAPK inhibitor?SB203580,PD98059,SP600125?were used to study MAPK pathway involvement in phosphorylation of ER? S105 and anti-EMT effect on eutopic EECs.Result?s?:Higher levels of phosphorylation of ERP S105 was detected in endometriotic tissues.Phospho-defective ER?-S 105A influences cell proliferation,migration,invasion and regulated EMT progress in endometriosis and ER?-S 105E was found to exhibit higher transactivation activity than ER?.In vitro,LXA₄ decreased IL-1?-induced phosphorylation of ER? S105 and p38 MAPK of eutopic EECs and pS105-ER? as targets of p38 and JNK kinases.Conclusion?s?:Phosphorylation of human estrogen receptor-beta at serine 105 suppresse cell migration,cell invasion and cell growth by regulated the transactivation activity of ER?.