To study the expression of vasculogenic mimicry (VM) and matrix metalloproteinase(MMP)-2 in endometrial carcinoma (EC) tumor tissue and their clinical relationship with EC.

A total of 52 EC patients at the Jinan Military General Hospital from October 2010 to December 2013 were selected as EC group, which underwent hysterectomy and had complete clinical data. Another 21 cases over the same period as control group, which had hysterectomy because of the uterine fibroids or other benign diseases. Furthermore, 12 cases of pathological findings diagnosed as atypical endometrial hyperplasia(EIN) patients were selected as EIN group. Endometrial paraffin-embedded sections of all patients were taken for the study. All of the paraffin-embedded sections adopted staining of CD₃₄ and periodic acid-schiff (PAS) together, and observed the expression of VM in three groups, while the paraffin-embedded sections of EC group were stained by immunohistochemistry streptavidin-perosidase (SP) in order to observe the expression of MMP-2. The differences of the positive expression rates of VM and the high expression rates of MMP-2 in different clinical factors among 52 cases of EC patients, including age, International Federation of Gynecology and Obstetrics(FIGO) clinical stages, World Health Organization(WHO) pathological differentiated grading, the infiltrating depth of muscular layer and whether had lymph node metastasis, were statistically analyzed. Meanwhile, the correlation between the expression of VM and MMP-2 in EC group were analyzed. This study followed the Ethical Standards of the Human Trials Committee of the Jinan Military General Hospital, had the approval of the commission. Informed consent was obtained from each participant. There were no significant differences among three groups in general clinical data, such as the age, menopause, childbearing history, menstrual history, etc.(P>0.05).

①The positive rate of VM in the tumor tissue of EC group was 30.8%(16/52), but did not find VM express in endometrium in control group and EIN group. ②The positive expression rate of VM in stageⅠpatients of FIGO was lower than that of stage Ⅲ-Ⅳ(14.3%vs 70.0%), and the difference was statistically significant(P=0.002); WHO pathological differentiated grading between well, moderately and poorly differentiation of the EC patients had pairwise comparisons, showed the higher level of differentiation had a lower VM positive expression rate than the lower level of differentiation, and the differences were statistically significant(P<0.05); The VM positive expression rate in patients with lymph node metastasis was higher than that in patients without lymph node metastasis(66.7%vs 23.3%), and the difference was statistically significant(χ²=4.704, P=0.030); There were no significant differences of VM positive expression rate between ≤50 years and >50 years old patients, between patients with infiltrating depth of muscular layer <1/2 and ≥1/2(P>0.05). ③The high expression rate of MMP-2 in patients with lymph node metastasis was higher than that in patients without lymph node metastasis(88.9%vs 23.2%), and the difference was statistically significant(χ²=11.413, P=0.000); There were no significant differences of high expression rate of MMP-2 between patients ≤50 years and >50 years old, among FIGO clinical stageⅠ, Ⅱ and Ⅲ-Ⅳ, among WHO pathological differentiated grading of well, moderately and poorly, between the infiltrating depth of muscular layer <1/2 and ≥1/2(P>0.05). ④The correlation of expression level of VM and MMP-2 were positively correlated in the 52 cases tumor tissue in EC group(r=0.478, P=0.000).

VM exists in some EC tissues and was related to the severity of EC. MMP-2 may promotes the formation of VM. Both of VM and MMP-2 may together promote the lymph node metastasis of EC patients.