PBK and esophageal squamous cell carcinoma: In esophageal squamous cell carcinoma, TOPK was positively correlated with tumor metastasis (Seol et al., 2017; Zykova et al., 2017; Ma et al., 2019) by activating Src/GSK3β/STAT3 signaling pathway (Jiang et al., 2019).