We combined the above two HCC patient cohorts and collected a total of 22 clinicopathological variables (Supplemental Table 3), from which we screened the four most useful predictors including tumor size, gamma-glutamyl transferase (γ-GT), neutrophil to lymphocyte ratio (NLR) and CCL21, with non-zero coefficients in the LASSO regression model (Fig. 2A, B and Supplemental Table 4). This evidence concerns the gene CCL21 and hepatocellular carcinoma.