To analyze the association between these 14 differentially expressed apoptotic genes and OS in HCC patients, we performed a univariate Cox regression analysis and screened four apoptotic genes (CASP8, BMF, BAK1, CSE1L) closely associated with OS in HCC patients (P < 0.05) (Figure 1D). This evidence concerns the gene CASP8 and hepatocellular carcinoma.