HLA-DOA and neoplasm: HLA-C, which belongs to HLA-I and can present endogenous tumor antigens to kill tumor cells effectively, was less expressed in the high-risk group, while HLA-II, such as HLA-DPB2, HLA-DQB2, HLA-DOA, and HLA-DQA2, showed an increase in the high-risk group (Figure 9D).