PBK and cancer: Furthermore, in the analyzed data set of cancer patients, it was found that MELK expression was strongly correlated with that of TOPK in various types of cancers such as prostate adenocarcinoma and renal clear cell carcinoma (Pearson's correlation coefficient R values are 0.82 and 0.81, respectively), and moderately correlated with lung adenocarcinoma (R = 0.55) (Supplementary Figure 6).