E2F1 and cancer: To much better understand the potential molecular mechanism of CENPN in HepG2 and Huh7 cells, we focused on three signaling pathways according to the GSEA results—P27, P21 and Rb/E2F1, which play a vital role in HCC and various cancers (Gartel, 2009; Razavipour, Harikumar & Slingerland, 2020; Rubin, Sage & Skotheim, 2020).