Kaplan-Meier survival analysis showed that increased E2F2 was significantly associated with poor OS (p = 7.468e− 05), PFI (p = 3.183e− 05), DFI (p = 0.001), DSS (p = 4.172e− 05), which indicated that HCC patients with high-E2F2 may have a worse prognosis than that with low-E2F2 (Fig. 3a-d). The gene discussed is E2F2; the disease is hepatocellular carcinoma.