Immunohistochemical staining for MMR proteins showed a loss of PMS2 expression in tumor cells and vascular endothelial cells (Additional file 3: Figure S2a) and preserved expression of MLH1 (Additional file 3: Figure S2b), MSH2 (Additional file 3: Figure S2c) and MSH6 (Additional file 3: Figure S2d) in both tumor cells and vascular endothelial cells. Here, MSH6 is linked to neoplasm.