Importance of MutL homologue MLH1 and MutS homologue MSH2 expression in Turkish patients with sporadic colorectal cancer

Figure 1 MLH1 and MSH2 expression. A: Nuclear MLH1 expression detected in germinal centre of lymphoid follicule (dark arrows) and in epithelia of normal colonic mucosa (× 100); B: Crypt epithelia showing normal positive nuclear staining with MSH2 (× 200).

Figure 2 MLH1 and MSH2 expression. A: Extensive nuclear staining with MLH1 in adenocarcinoma of colon (× 200); B: Tumor cells showing strong positive nuclear staining with MSH2 (× 100).

Figure 3 Loss of MLH1 and MSH2 expression in colorectal cancer. A: Loss of staining with MLH1 in cancer cells, although lymphocytes (arrow) show positive staining (× 400); B: Adenocarcinoma with complete loss of MSH2 expression. Nuclear staining of lymphocytes (arrows) in the stroma served as internal positive control (× 200).