MLH1 and neoplasm: Immunohistochemical staining of tumor cells (III-1 and II-2) demonstrated moderate positivity for MLH1 (Figures 2A,I) and PMS2 (Figures 2C,K) proteins, weak positivity for MSH6 (Figures 2D,L), and lack of expression of MSH2 protein (Figures 2B,J).