KLRK1 and malignant colon neoplasm: Regarding the most resistant colon cancer lines, some evidence has demonstrated that Colo 205 cells are generally resistant to killing by natural killer cells due to high expression of HLA‐A, HLA‐B, and HLA‐C molecules (ligands of KIR receptors, [74]), CD155 (ligand for CD96 and TIGIT, inhibitory receptors; [75]), and low expression of MICA (ligand for NKG2D, one of the main activating NK receptors; [76]).