Expression and Signification of COX-2 in Ectopic and Eutopic Endometria in Ovarian Endometriosis
|Course||Obstetrics and Gynaecology|
|Keywords||Cyclooxygenase-2 ( COX-2 ) endometriosis endometrium prostaglandin|
Objective:Cyclooxygenase is an important speed limit enzyme toregulate the production of prostaglandins from arachidonic acid.One of its isoforms,COX-2,is mainly expressed at the cell plasmand the circumference of nucleolus. It works in the reticulationframework out of cells and the margin of nucleolus. It participatein the course of procreation and delivery in normal conditions andin the occurrence and progression of inflammation and carcinomaincluding the female genitalia in pathologic conditions. The overexpression of cox-2 maybe work in the course of shaping bloodvessel in endometriosis,accordingly arouses a lot of symptoms,such as dysmenorrhea and sterility. In this article,we are toexplore the expression of Cyclooxygenase-2(COX-2 ) in eutopicand ectopic endometria in endometriosis and in eutopic endometriain control women,and the effect to the occurence and progress ofendometriosis.Method:The subjects consisted of 90 women who were treated atthe Department of Obstetrics and Gynecology at the three hospitalpertaining to Jilin University. They were divided into two groups:(i) fertile controls(n = 45,the average age is 32.1) and (ii) theendometriosis group (n = 45,the average age is 33.3). Beforestarting any medication in the control group , or afterhysterectomy in the patients with endometriosis , eutopicendometrial tissue was obtained when it became available duringany phase of the menstrual cycle(15 in the proliferative phase,15in the secretory phase and 15 in the menses phase.). Ectopicendometrial tissues in ovarian chocolate cysts in endometriosiswere studied in the identical patients at the same time (20 in theproliferative phase and 30 in the secretory phase). Endometriosispatients associated with adenomyosis were excluded from thepresent study. The controls consisted of 45 fertile women withregular and biphasic menstrual cycles. None of controls hadidentifiable endometriosis confirmed. In the control and theendometriosis group,eutopic endometrial specimens were obtainedby curettage or by hysterectomy. The tissues were fixed inneutral-buffered 10% formalin solution. The samples were cut intoblocks,eparaffinized,serial 4-5 um sections of tissue were cut.The sections were stained immunohistochemically,stained withdiaminobenzidine (DAB) and counterstained with haematoxylin. Ineach run,a section of ovarian carcinoma with strong COX-2staining was routinely included as a positive control. Tennon-overlapping fields of view were examined per biopsy in asystematic random sampling pattern (magnification x400). Surfaceepithelial cells or endometrial glandular epithelial cells wereassessed. The frequency was defined as 1+,2+ or 3+ when thenumber of positive cells in the endometrium in each section was<10%,10–50% or >50% respectively.Result: The expression of COX-2 in surface and glandularepithelia of the control group varied markedly during the menstrualcycle. It was lowest in the early proliferative phase and graduallyincreased thereafter. It remained high throughout the secretoryphase. However, in patients with endometriosis,expression ofCOX-2 in glandular epithelium was higher than that in the controlgroup , though it varied throughout the menstrual cycle.Overexpression COX-2 was observed in glandular cells fromectopic endometrial tissue of ovarian chocolate cyst walls in allcases regardless of the menstrual phase.1. There was no difference in age from all groups. Age as a mixed factor was excluded.2. Variation in COX-2 expression during the menstrual cycle in eutopic endometrium in control group:Expression of COX-2 in the surface epithelium in the control group varied markedly during the menstrual cycle. It was lowest in the early proliferative phase and gradually increased thereafter. It remained high throughout the secretory phase and peaked in menses phase. P<0.01 among the seven phases eutopic endometrium in the control group by the Kruskal–Wallis test.3. Variation in COX-2 expression during the menstrual cycle in eutopic endometrium in ovarian endometriosis:In patients with endometriosis,it showed a similar tendency. However,it varied throughout the menstrual cycle,but expression of COX-2 wassignificantly more pronounced than that in the control group. P<0.01 among the seven phases eutopic endometrium in the endometriosis group by the Kruskal–Wallis test.COX-2 expression in ectopic endometrium in ovarianendometriosis:Expression of COX-2 was observed in ectopicendometrial tissue in all cases. COX-2 expression in glandularepithelium cells in ovarian chocolate cyst wall were higher thanthat in eutopic endometrium in the secretory phase and mensesphase of the control group or the ovarian endometriosis group.P<0.01 among the seven phases ectopic endometrium in theendometriosis group by the Kruskal–Wallis test. And P<0.01among eutopic endometrium the control group, eutopicendometrium in the endometriosis group and ectopic endometriumin ovarian endometriosis by the Kruskal–Wallis test.Conclusion :1. The expression of COX-2 in surface and glandular epithelia of the control group varied markedly during the menstrual cycle.2. Overexpression COX-2 was observed in glandular cells from ectopic endometrial tissue of ovarian chocolate cyst walls of endometriosis.3. There is some close relationship between the over expression of COX-2 and the occurrence and progression of ovarian endometriosis.The occurrence and progression of endometriosis is cooperatewith polygene many factors and many steps,it involves manyfactors such as gene breaking , immunology changing ,physiological and biochemistry chaging , hormone abnormityadjusting and etc. The over expression of COX-2 is only one facetof those. To lucubrate COX-2 maybe open out the mechanism ofendometriosis on the other hand,and can provide the therapy withnew tactics. On the other hand,the variety of COX-2 expression indifferent period of endometriosis,and how it expresses at theectopic endometrium in other position of endometriosis and inadenomyosis still need more research. NSAIDs and other COX-2inhibitors have been applied to treat endometriosis in foreign clinic.