Dissecting the phenotypes of Plk1 inhibition in cancer cells using novel kinase inhibitory chemical CBB2001.
Polo-like kinase 1 (Plk1) is a mitotic serine/threonine kinase and its kinase activity is closely interrelated to cell cycle progression, various types of cancer development and often correlates with poor prognosis. Thus, it is of prime importance to characterize the phenotypes of Plk1 inhibition in cells for drug development and clinical application. Here, we report a novel kinase inhibitory chemical, CBB2001, which specifically inhibited Plk1 kinase activity in vitro with an IC(50) of 0.39 μM. In cervical carcinoma HeLa cells, we found that treatment of CBB2001 caused mitotic cell cycle arrest (EC(50)=0.72 μM) and induction of 'polo' cells (EC(50)=0.32 μM). Interestingly, the cell cycle arrest induced by CBB2001 was associated with accumulation of Plk1 (EC(50)=0.61 μM) and Geminin (EC(50)=0.43 μM) proteins, but distinct from the phenotypes induced by Aurora kinase inhibitors. The inhibitory effects of CBB2001 were phenocopied by RNA interferences of Plk1. We also confirmed the cell cycle inhibitory effects of CBB2001 in other cancer cells. Moreover, CBB2001 inhibited the growth of HeLa cells with an IC(50) of 0.85 μM in MTT assays, which is better than that of reported Plk1 inhibitory chemicals ON01910 (IC(50)=6.46 μM) and LFM-A13 (IC(50)=37.36 μM). CBB2001 also inhibited mouse xenograft tumor growth. Furthermore, CBB2001 inhibited mitotic exit and delayed degradation of APC/C substrates, Geminin, Cyclin B1 and Aurora A. These specific phenotypes may serve as specific features for Plk1 inhibition and for Plk1-based clinic trials.
Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China.
Rongfeng
R
Lan
Guimiao
G
Lin
Feng
F
Yin
Jun
J
Xu
Xiaoming
X
Zhang
Jing
J
Wang
Yanchao
Y
Wang
Jianxian
J
Gong
Yuan-Hua
YH
Ding
Zhen
Z
Yang
Fei
F
Lu
Hui
H
Zhang
D000577:Amides / Q000494:pharmacology; D000818:Animals; D064096:Aurora Kinase A; D064127:Aurora Kinases; D001562:Benzimidazoles / Q000737:chemistry / Q000494:pharmacology*; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D056744:Cyclin B1 / Q000378:metabolism; D005260:Female; D064248:Geminin; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D020128:Inhibitory Concentration 50; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009369:Neoplasms / Q000201:enzymology* / Q000473:pathology; D009570:Nitriles / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D013450:Sulfones / Q000494:pharmacology; D013844:Thiazoles / Q000737:chemistry / Q000494:pharmacology*; D000097869:Polo-Like Kinase 1
D000577:Amides; D064096:Aurora Kinase A; D064127:Aurora Kinases; D001562:Benzimidazoles; D018797:Cell Cycle Proteins; D056744:Cyclin B1; D064248:Geminin; D005998:Glycine; D009570:Nitriles; D047428:Protein Kinase Inhibitors; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D013450:Sulfones; D013844:Thiazoles; D000097869:Polo-Like Kinase 1; C577235:CBB2001; C577995:GMNN protein, human; C118451:LFM A13; C507134:ON 01910; C576918:Aurka protein, mouse