Previous studies suggested that these NK cell marker genes involve immune regulatory processes (For example, NINL and KDM6B in gastric cancer72,73, PLAAT4 in pancreatic carcinoma59, SKIL in non-small cell lung cancer74, MT1E in liver cancer75, ASCL2 in colorectal cancer)76 in solid malignant tumors. The gene discussed is PLAAT4; the disease is colorectal cancer.