A 2017 study by Dong et al25 found that GTPase (KRAS) (OMIM 190070) mutation, a TP53 and KRAS proto-oncogene, may boost PD-L1 expression, T-cell infiltration, and augment tumor immunogenicity, resulting in a response to programmed cell death protein 1 and PD-L1 inhibitor. This evidence concerns the gene PDCD1 and neoplasm.