The Vascularization In Endometriosis

Endometriosis is a disorder in which abnormal growths of endometrial tissue arepresent in locations other than the uterine lining and which most occurs in pelvicperitoneum, and is also found in ovarian (known as ovarian endometriosis), rectovaginalseptum, and ureter, occasionally appears in the bladder, pericardium, and pleura.Endometriosis is a kind of benign lesion, but can develop to be atypical hyperplasia, andeven carcinoma such as endetrial carcinoma of ovary or clear cell carcinoma with thestrong invasive and metastasis ability. Recent studies reveal that neovascularization mayplay an important role in the development of endometriosis．Vascular endothelial growthfactor (VEGF) and angiopoietin-2(Ang-2) as the important angiogenic factorshave beenidentified that they play the key role in the angiogenesis of malignant tumor，but their rolein the pathogenesis of endometriosis are not yet clear.Objective: To identify whether vascular endothelial cell growth factor (VEGF) andangiogetin-2are involved in the pathogenesis of endometriosis, we detected the expressionof VEGF and Ang-2in several histopathological specimens from the patients with ovarianendometriosis compared with which from the patients with tubal infertility as normalcontrols, analyzed their roles in the angiogenesis of ovarian endometriosis,and theirrelationships to the clinical pathological characteristics of ovarizan endometriosis, furtheranalyzed the correlation between VEGF and Ang-2, and attempted to discuss thecorrelation of VEGF and Ang-2to the development of ovarian endometriosis.Methods: Specimen collection: total60infertility cases accepted hysteroscopecombined with laparoscope inspections inJingjiang People’s Hospital from December of2010to December of2012were collected in this study. The endometrium tissues andperitoneal fluids from30ovarian endometriosis (ectopic endometrium) cases, which wereconfirmed by pathological reports, were examined in the following studies compared with those from the30tubal infertility cases as controls.. ELISA was used to detect theexpression of Ang2, VEGF, and MVD (to mark the microvascular density of positive bloodvessels) in the peritoneal fluid, and immunohistochemistry was applied to observe theexpression of above indicators in the tissue samples.Statistic analysis: The SPSS19.0software was used for statistic analysis. Chi-squaretest was applied to analyze the ratio between two samples, the Mann-Whitney rank sumtest was used to analyze the ranked data, spearman correlation analysis was used for thecorrelation analysis, and t-test or ANOVA was used to analyze the measurement data.P<0.05was considered as significant difference.Results：(1) The expression of VEGF is significantly higher in the peritoneal fluid from theendometriosis cases than those in the control group, which is increased as theendometriosis worsen (P<0.05).(2) VEGF is expressed mainly in the cytoplasm of endometrial epithelial cells andvascular endothelial cells, and dispersedly in the interstitial cells. VEGF and Ang-2areexpressed in the endometrium tissues from the endometriosis cases, and which aresignificantly higher than those from the control group (P <0.05). In the control groupexpression difference is not obvious, no statistical significance.(3) Expression of VEGF and Ang-2are significantly higher in the inner wall of theectopic cyst than those in the endometrium from the observation group or the control group.(P <0.05).(4) The results of linear correlation analysis show that the correlation coefficient (r)of Ang-2and VEGF E in the observation group, control group were0.658(P <0.05),0.912(P <0.01), and0.231(P>0.05) respectivelly; the “r” of Ang-2and MVD inobservation group, control group in the correlation coefficient r were0.932(P <0.01),0.648(P <0.05), and0.357(P>0.05) respectively; the “r” of VEGF and MVD in theobservation group, control group in the correlation coefficient r were0.661(P <0.05),0.851(P <0.01) and0.529(P <0.05) respectively. Conclusion:1. The expression of VEGF/Ang-2in ectopic endometrium and peritoneal fluid ofendometriosis cases are significantly higher than in control group. It indicatesthat they may play important roles in the development of endometriosis.2. The expression of VEGF in eutopic or ectopic endometrium is higher than that inthe control endometrium. It suggests that VEGF may act as a principal status inthe development of endometriosis.3. MVD in the ectopic endometrium is higher than that in the control endometrium.It suggests that vascular formation is existed during the implantation of ectopicendometrium and make it possible to implant successfully.4. The expression of VEGF is highly correlated with the expression of Ang-2, whichsuggests that they may function together to promote the development ofendometriosis. Therefore, they may become the new target in the dignosis andtherapy of endometriosis.