PBK/TOPK is highly expressed in several types of cancer including lung adenocarcinoma (Xiao et al., 2019), ovarian cancer (Ikeda et al., 2016), gastric carcinoma (Ohashi et al., 2017), breast cancer (Park et al., 2006), nasopharyngeal carcinoma (Wang et al., 2016), and colon cancer (Zhu et al., 2007). Here, PBK is linked to breast cancer.