RPAP2 and neoplasm: To further investigate whether RPAP2 promotes the in vivo growth of HCC cells, we used a xenograft mouse model and found that lentiviral shRNA‐mediated knockdown of RPAP2 (Figure 1I; Figure S2A, Supporting Information) almost completely inhibited the growth of Huh7 and Hep3B cells in vivo, as evidenced by the decreased tumor volume and weight (Figure 1J–L; Figure S2B–D, Supporting Information).