Fig. 2

MMR protein expression of the probands in the two families. A, B Hematoxylin–eosin staining of the proband’s tumor tissues. Histopathological examination of the tumor revealed villous-tubular adenoma accompanied by high-grade glandular intraepithelial neoplasia and focal sections of moderately and well-differentiated intramucosal adenocarcinoma. C–J Immunohistochemistry analysis. From the left to right, images show staining of the proband’s tumor tissues from families 1 and 2, respectively. From top to bottom, the antibodies in each line are specific for MLH1, MSH2, MSH6, and PMS2. Loss of expression of MSH6 in family 1 and loss of expression of MLH1/PMS2 in family 2 were observed. All images were captured at 200 × magnification