MAD1L1 and hepatocellular carcinoma: In order to further analyze the functional enrichment of NEK2 and its interacting proteins (MAD1L1, CEP250, MAPK1, NDC80, NEK11, PPP1CA and PPP1R2) in HCC, GO and KEGG pathways were investigated based on DAVID [27] and KOBAS 3.0 [28] databases.