KRAS and cancer: It has been found that mutations in cancer driver genes, KRAS, EGFR, ALK, human epidermal growth factor receptor 2 (HER2), STK11, CDKN2A, TP53, etc. [7], dysregulate the expression of the PD-1 and PD-L1 and PD-1/PD-L1 signaling pathways, which are associated with resistance in immunotherapy [219,220,221].