Overexpression of the αvβ6 Integrin in Endometrial Cancer

The alpha(v)beta(6) integrin (alpha v beta 6) has been shown to be Up-regulated in adenocarcinoma of the breast, colon, stomach, and ovary, generally reflecting a more aggressive phenotype. Expression ill endometrial cancer has not been reported. We analyzed alpha v beta 6 expression in the tissue from primary endometrial carcinomas (endometrioid type) using a mouse monoclonal antibody against human alpha v beta 6, and correlated the findings with grade, stage, and nodal involvement. Normal cycling endometrium was studied For comparison. alpha v beta 6 was only weakly expressed in normal epithelium and infrequently expressed in precancers, but up-regulated in the majority of endometrial carcinomas, especially with high grade. Nodal metastases strongly expressed alpha v beta 6, even when the primary tumor showed only focal expression. No correlation was found between expression and depth of invasion or the presence of metastases. Overexpression of alpha v beta 6 in endometrial carcinoma is common. Expression is high in metastatic lesions. The level of expression of the primary tumor was not indicative of the presence of nodal metastasis; however, the number of cases with nodal metastases was limited.