MMR defects led to a higher rate of somatic cell mutation, which increased the tumor antigen load and the number of tumor-infiltrating lymphocytes of these tumors with MMR defects, corresponding to the increased expression of PD-1 as well as PD-L1 (du Rusquec et al., 2019; Howitt et al., 2015). The gene discussed is CD274; the disease is neoplasm.