Baicalin suppresses lung cancer growth by targeting PDZ-binding kinase/T-LAK cell-originated protein kinase

Baicalin is the main bioactive components extracted from the traditional Chinese medicine Baical Skullcap Root, and its anti-tumor activity had been studied in previous studies. PDZ-binding kinase/T-LAK cell-originated protein kinase (PBK/TOPK), a serine/threonine protein kinase, is highly expressed in many cancer cells and stimulates the tumorigenic properties, and so, it is an pivotal target for agent to cure cancers. Nowadays, we reported for the first time that baicalin suppressed PBK/TOPK activities by directly binding with PBK/TOPK in vitro  and in vivo . E x vivo  studies showed that baicalin suppressed PBK/TOPK activities in JB6 Cl41 cells and H441lung cancer cells. Moreover, knockdown of PBK/TOPK in H441 cells decreased their sensitivities to baicalin. I n vivo study indicated that injection of baicalin in H441 tumor-bearing mice effectively suppressed cancer growth. The PBK/TOPK downstream signaling molecule Histone H3 and ERK2 in tumor tissues was also decreased after baicalin treatment. Taken together, baicalin can inhibit proliferation of lung cancer cells as a PBK/TOPK inhibitor both in vitro  and in vivo .