Due to its distribution, protein kinase activity, and specific roles in the mitotic progression and cellular proliferation of actively proliferative cells, PBK/TOPK has drawn the attention of many scientists and clinicians seeking to understand its involvement in tumor proliferation, metastasis, and chemoresistance and to elucidate its potential as a diagnostic and prognostic marker, as well as a therapeutic target in various types of cancers. Here, PBK is linked to cancer.