SPINK1 and hepatocellular carcinoma: We performed a subpopulation analysis on the HCC cells and obtained seven subpopulations, including APOA1+ HCC, SPINK1+ HCC, APOA1+SPINK1+PLA2G2A+ HCC, DDX5+ HCC, APOC2+ HCC, AIF1+ HCC, and CLDN10+ HCC (Figures 2A, B).