E2F4 and hepatocellular carcinoma: E2F1, E2F2, E2F3, E2F4, and E2F8 are shown to be upregulated human HCC and promote cancer progression (Palaiologou et al., 2012; Liu et al., 2003a; Liu et al., 2003b; Deng et al., 2010; S et al., 2021).