RAP2A and hepatocellular carcinoma: LASSO regression analysis selected the combination of 8 genes related to HCC survival to produce the final prognostic classification model (Fig. 3A, B): risk score = 0.136 × BMI1 + 0.088 × AGPS + 0.076 × RAP2A + 0.162 × FAM83D + 0.085 × SKP2 + (− 0.122 × SLC2A2) + 0.109 × SGCB + (− 0.064 × SPP2).