The Role Of C-fos And MMP-9 In The Pathogenesis Of Endometriosis

Endometriosis,the presence of viable endometrial tissue outside the uterus, affects 10-15%of reproductive age women.This disease is frequently associated with pelvic pain and has been recognized as a major cause of infertility among women in many industrialized nations.A variety of theories have been proposed to account for this susceptibility,including genetic predisposition,aberrant immunologic response and an altered peritoneal environment and so on.But the precise pathogenesis mechanism remains largely unknown up to date.Even though endometriosis is considered a benign disorder,it exhibits some characteristics of malignancy that are also seen in malignant lesions,such as cellular atypical hyperproliferation,invasion,metastasis,neoangiogenesis and genomic instability. Among these,invasion is the most important characteristic of malignancy.Some key moleculars which promote the invasion and metastasis of tumor might play the similar role in the ectopic transplantation of endometrium.In the past few years, some research focused on the importance of matrix metalloproteinases(MMPs)in the pathogenesis of endometriosis,but only a few tried to find out the upstream moleculars which control the expression of MMPs.c-fos represents an estrogen early response gene,because its expression is rapidly and dramatically induced by estrogen.Recent research showed that c-fos might promote cancer cell invasion by regulating the MMPs expression.MMP-9, an important enzyme for degradation of extracellular matrix,is reported to be involved not only in tumor invasion and metastasis,but also in progression of endometriosis.Interestingly,the MMP-9 gene is encoded on chromosome 20,and its expression is under the control of a 2.2-kb upstream regulatory sequence harboring binding sites for AP-1,implying the critical role played by AP-1 subunit c-fos in regulating MMP-9 expression.Recent studies have shown that there was a tight relationship between MMP-9 and c-fos expression in malignant tumor invasion.Because of the invasive characteristic shared by endometriosis and malignant tumor,it is possible that c-fos and MMP-9 might cooperate to promote the development of endometriosis.To the best of our knowledge,this is the first report to study the role of c-fos in the pathogenesis of endometriosis,and also the first report to demonstrate the relationship among c-fos,MMP-9 and estrogen during the ectopic transplantation of endometrium.Interiorly,Boyden transwell was used to detect the invasion ability of endometrial cell for the first time,providing a new method to study the mechanism of endometriosis.We first examined the protein expression of c-fos and MMP-9 in paired eutopic and ectopic endometria of the endometriotic patients and in eutopic endometria from the control patients,and the correlation of c-fos protein expression with MMP-9 protein expression and serum estrogen level was also studied.In the next in vitro experiment,the role of estrogen,c-fos and MMP-9 in the invasion of endometrial cell was examined by Boyden transwell combined with siRNA technique. Partâ… Protein expression of c-fos and MMP-9 in the ectopic and the eutopic endometria from women with or without endometriosisObjective:To investigate c-fos and matrix metalloproteinase-9(MMP-9) expression in the endometrium from women with or without endometriosis throughout the menstrual cycle,and to explore the correlation of c-fos expression with MMP-9 expression and E₂ levels in serum.Method:Localization of c-fos in the endometrium was examined by immunohistochemistry,c-fos and MMP-9 protein levels in the endometrium was detected by Western blotting,and E₂ levels in serum was determined by electro-chemiluminescence immunoassay,in fifty-five premenopausal women(25 with endometriosis and 30 without endometriosis)undergoing laparoscopic surgery or hysterectomy.Result(s):c-fos protein was predominantly located in the nuclei of glandular epithelial cells and stromal cells,c-fos and MMP-9 protein levels in paired eutopic and ectopic endometria from women with endometriosis were significantly higher than those in the endometrium from women without endometriosis.No significant difference in c-fos or MMP-9 protein levels was observed between paired eutopic and ectopic endometria.C-fos protein levels were higher in proliferative phase compared with secretory phase in all the three groups of endometria,and only the normal eutopic endometrium showed higher MMP-9 protein levels in proliferative phase.C-fos protein levels positively correlated with MMP-9 protein levels in all the endometria examined,and in proliferative phase,c-fos protein levels in the eutopic endometrium from women with or without endometriosis showed positive correlation with serum E₂ levels.Conclusion:The abnormal expression of c-fos and MMP-9 protein might be involved in the pathogenesis of endometriosis. Partâ…¡The role of Boyden transwell in the research of endometrial stromal cell invasion.Objective:To investigate the role of Boyden transwell in the research of endometrial stromal cell invasion.Method:Endometrial stromal cell was isolated and cultured from the eutopic endometrium of women without endometriosis.The role of estrogen and the receptor inhibitor in the invasion of endometrial stromal cell was examined by Boyden transwell.Result(s):All the four groups of cell showed invasion.Cells stimulated by estrogen showed larger invasion number compared with the control group, But the invasion cell number of the group affected by estrogen receptor inhibitor alone or with estrogen was the same with that of control group.Conclusion:The result from Boyden transwell method was consistent with the estrogen-dependent clinical performance of endometriosis and the research findings that estrogen receptor was located in the endometrial stromal cells, suggesting the importance of Boyden transwell as a model to study the invasion of endometrial cells and providing a new mehod to explore the pathogenesis of endometriosis. Partâ…¢The role of c-los and MMP-9 in the invasion promoting effect of estrogen on endometrial cellObjective:To investigate role of c-fos and MMP-9 in the invasion promoting effect of estrogen on endometrial cell.Method:Endometrial stromal cell was isolated and cultured from the eutopic endometrium of women without endometriosis;The effect of estrogen and the receptor inhibitor on c-fos and MMP-9 protein expression in endometrial stromal cell was examined by Western blotting;small interfering RNA(siRNA)was used to silence c-fos and MMP-9 gene expression respectively,then the invasion ability of c-fos or MMP-9 gene silenced cells under the stimulation of estrogen was determined by Boyden transwell.MMP-9 protein expression level in c-fos gene silenced cells under the stimulation of estrogen was also observed.Result(s):â‘ c-fos and MMP-9 protein levels in endometrial stromal cells were upregulated by estrogen,and this upregulation could be inhibited by estrogen receptor inhibitor;â‘¡All the groups of cell showed invasion,with the greatest invasion cell number in the estrogen group;invasion cell number of c-fos or MMP-9 gene silenced cells under the stimulation of estrogen was significantly reduced compared with the estrogen group,but was still higher than that of control group;â‘¢MMP-9 protein expression level in c-fos gene silenced cells under the stimulation of estrogen was the same with that in the control group.Conclusion:â‘ Estrogen and its receptor might cooperate in regulating c-fos gene expression,which controls MMP9 gene expression,and then promotes the invasion ability of endometrial stromal cell;â‘¡c-fos and MMP-9 was one of the key moleculars in mediating the cell invasion promoting effect of estrogen.