To investigate the correlation of aquaporin protein 1 (AQP1) expression and microvessel density (MVD) in adenocarcinoma endometrium, and discuss the roles of aquaporin protein 1 and microvessel density in the process of adenocarcinoma endometrium.

From June 2007 to June 2009, 55 cases who diagnosed as adenocarcinoma endometrium in Yantai Mountain Hospital of Yantai City were included into this study (AC group), including 50 patients underwent surgical resection and 5 patients underwent curettage diagnosis (they gave up surgery) specimens (stage Ⅲ or Ⅳ). Meanwhile, another 31 cases with atypical hyperplasia endometrial tissues were included into EIN group. Another 15 cases that underwent hysterectomy or subtotal hysterectomy were included into control group. Age distribution of patients among AC group, EIN group and control group had no significant difference (P>0.05). The study protocol was approved by the Ethical Review Board of Investigation in Human Being of Yantai Mountain Hospital of Yantai City. Informed consent was obtained from all participants. Expression of aquaporin protein 1 and microvessel density in adenocarcinoma endometrium were detected by immunohistochemistry.

Aquaporin protein 1 expressed mainly in the capillaries of the organizations and small vascular endothelial cells. With the development of endometrial lesions, aquaporin protein 1 expression and vascular density gradually increased. Aquaporin protein 1 expression among three groups had significant differences (P<0.001). In AC group, when histopathologic grade was G2/G3, depth of myometrial invasion > 1/2, clinical stage was Ⅱ, Ⅲ/Ⅳ with lymph node metastasis, aquaporin protein 1 had the high expression. In AC group, aquaporin protein 1 expression and vascular density was positively correlated (r=0.689, P< 0.001).

Aquaporin protein 1 in the development of adenocarcinoma endometrium is closely related with angiogenesis.