PLK1 and breast carcinoma: Other genes such as BUB1, NUF2, CDC20, ASPM, KIF2C, and PRC1 have biological relevance to breast cancer progression, and PLK1, NDC80, and CCNB2 only to TNBC progression, and these genes predict worse prognosis (Wang et al., 2015; Tang et al., 2019; Yang et al., 2019; Lv et al., 2020; Ren et al., 2020; Chen et al., 2021; Jiang et al., 2021; Koyuncu et al., 2021); likewise, we also found that these genes correlated negatively with prognosis in the TNBC subtype.