CCNB1 and cancer: At present, many studies have shown that the hub genes CDC20, CDK1, BUB1, CCNB1, and BUB1B identified in our PPI network are involved in cancer progression (Zhang et al., 2018; Piao et al., 2019; Li et al., 2020; Zhang et al., 2020; Gao et al., 2021).