As for MHC molecules, we found the MHC class II molecules including HLA-DPA1, HLA-DPB1, HLA-DRA, HLA-DRB1, HLA-DQA1, HLA-DQB1 showed a stronger relation with PD-1 than other MHC molecules in some cancer types. This evidence concerns the gene HLA-DQA1 and cancer.