Fig. 2
From: Molecular genetics of microsatellite-unstable colorectal cancer for pathologists
Immunohistochemistry for mismatch repair proteins in a patient with sporadic hypermethylation of the MLH1 promoter. Hematoxylin & eosin (H&E) stain of the adenocarcinoma (a). Tumor cells show loss of MLH1 nuclear expression (b) and loss of PMS2 nuclear expression (c) while the stroma and lymphocytes shows strong intact staining. Conversely, tumor cells show intact nuclear expression of MSH2 (d) and MSH6 (e). This tumor showed BRAF V600E mutation by PCR consistent with sporadic microsatellite-unstable colorectal carcinoma