LILRB2 and colorectal carcinoma: Based on the mean serum expression levels of LILRB2 and APE1 (LILRB2: 402.18; APE1: 0.48), the 100 CRC patients were stratified into high- and low-expression groups for each marker (LILRB2: n = 51 high, n = 49 low; APE1: n = 50 high, n = 50 low).