7-O-Methylwogonin from Scutellaria baicalensis Disturbs Mitotic Progression by Inhibiting Plk1 Activity in Hep3B Cells

Abstract

Polo-like kinase 1, a mitotic Ser/Thr kinase, has emerged as a molecular target for the development of anticancer drugs. In this study, we found that polo-like kinase 1 activity was inhibited by 7-O-methylwogonin and related flavones, including baicalein, dihydrobaicalein, and viscidulin II, isolated from Scutellaria baicalensis. Although dihydrobaicalein exhibited the highest polo-like kinase 1 inhibitory activity among the four compounds, it also inhibited other kinases, such as vaccinia-related kinase 2 and polo-like kinase 2. Baicalein and viscidulin II also showed low selectivity to polo-like kinase 1 since they inhibited polo-like kinase 3 and polo-like kinase 2, respectively. However, 7-O-methylwogonin exhibited selective polo-like kinase 1 inhibitory activity, as evidenced from in vitro kinase assays based on fluorescence resonance energy transfer assays and ADP-Glo kinase assays. In addition, examination of mitotic morphology and immunostaining using specific antibodies for the mitotic markers, p-histone H3 and mitotic protein monoclonal 2, in Hep3B cells showed that 7-O-methylwogonin treatment increased mitotic cell populations due to inhibition of mitotic progression as a result of polo-like kinase 1 inhibition. The pattern of 7-O-methylwogonin-induced mitotic arrest was similar to that of BI 2536, a specific polo-like kinase 1 inhibitor. Thus, it was suggested that 7-O-methylwogonin disturbed mitotic progression by inhibiting polo-like kinase 1 activity. These data suggest that 7-O-methylwogonin, a polo-like kinase 1 inhibitor, may be a useful anticancer agent because of its polo-like kinase 1 selectivity and effectiveness.

Key words

7-O-methylwogonin - polo-like kinase 1 - Scutellaria baicalensis - Lamiaceae - anticancer - mitosis

^* These two authors contributed equally to this work.

• References

• 1 DeVita jr. VT, Chu E. A history of cancer chemotherapy. Cancer Res 2008; 68: 8643-8653
• 2 Che W, Liu B, Nie F, Wei Y, Li W, Chen W, Xu Y. Association of TNF-alpha with left ventricular diastolic dysfunction in patients with hepatitis C virus infection. Int J Cardiol 2013; 168: 2903-2904
• 3 Peng B, Hayes M, Resta D, Racine-Poon A, Druker BJ, Talpaz M, Sawyers CL, Rosamilia M, Ford J, Lloyd P, Capdeville R. Pharmacokinetics and pharmacodynamics of imatinib in a phase I trial with chronic myeloid leukemia patients. J Clin Oncol 2004; 22: 935-942
• 4 Gross S, Rahal R, Stransky N, Lengauer C, Hoeflich KP. Targeting cancer with kinase inhibitors. J Clin Invest 2015; 125: 1780-1789
• 5 Yim H, Erikson RL. Plk1-targeted therapies in TP53- or RAS-mutated cancer. Mutat Res Rev Mutat Res 2014; 761: 31-39
• 6 Liu X, Lei M, Erikson RL. Normal cells, but not cancer cells, survive severe Plk1 depletion. Mol Cell Biol 2006; 26: 2093-2108
• 7 Yim H, Erikson RL. Polo-like kinase 1 depletion induces DNA damage in early S prior to caspase activation. Mol Cell Biol 2009; 29: 2609-2621
• 8 Liu X, Erikson RL. Polo-like kinase (Plk)1 depletion induces apoptosis in cancer cells. Proc Natl Acad Sci U S A 2003; 100: 5789-5794
• 9 Dietzmann K, Kirches E, von Bossanyi P, Jachau K, Mawrin C. Increased human polo-like kinase-1 expression in gliomas. J Neurooncol 2001; 53: 1-11
• 10 Eckerdt F, Yuan J, Strebhardt K. Polo-like kinases and oncogenesis. Oncogene 2005; 24: 267-276
• 11 Knecht R, Elez R, Oechler M, Solbach C, von Ilberg C, Strebhardt K. Prognostic significance of polo-like kinase (PLK) expression in squamous cell carcinomas of the head and neck. Cancer Res 1999; 59: 2794-2797
• 12 Knecht R, Oberhauser C, Strebhardt K. PLK (polo-like kinase), a new prognostic marker for oropharyngeal carcinomas. Int J Cancer 2000; 89: 535-536
• 13 Weichert W, Kristiansen G, Schmidt M, Gekeler V, Noske A, Niesporek S, Dietel M, Denkert C. Polo-like kinase 1 expression is a prognostic factor in human colon cancer. World J Gastroenterol 2005; 11: 5644-5650
• 14 Takai N, Yoshimatsu J, Nishida Y, Narahara H, Miyakawa I, Hamanaka R. Expression of polo-like kinase (PLK) in the mouse placenta and ovary. Reprod Fertil Dev 1999; 11: 31-35
• 15 Yim H. Current clinical trials with polo-like kinase 1 inhibitors in solid tumors. Anticancer Drugs 2013; 24: 999-1006
• 16 Nuthalapati S, Zhou Q, Guo P, Lv H, Cosenza S, Reddy MV, Reddy EP, Gallo JM. Preclinical pharmacokinetic and pharmacodynamic evaluation of novel anticancer agents, ON01910.Na (Rigosertib, Estybon) and ON013105, for brain tumor chemotherapy. Pharm Res 2012; 29: 2499-2511
• 17 Sebastian M, Reck M, Waller CF, Kortsik C, Frickhofen N, Schuler M, Fritsch H, Gaschler-Markefski B, Hanft G, Munzert G, von Pawel J. The efficacy and safety of BI 2536, a novel Plk-1 inhibitor, in patients with stage IIIB/IV non-small cell lung cancer who had relapsed after, or failed, chemotherapy: results from an open-label, randomized phase II clinical trial. J Thorac Oncol 2010; 5: 1060-1067
• 18 Olmos D, Barker D, Sharma R, Brunetto AT, Yap TA, Taegtmeyer AB, Barriuso J, Medani H, Degenhardt YY, Allred AJ, Smith DA, Murray SC, Lampkin TA, Dar MM, Wilson R, de Bono JS, Blagden SP. Phase I study of GSK461364, a specific and competitive Polo-like kinase 1 inhibitor, in patients with advanced solid malignancies. Clin Cancer Res 2011; 17: 3420-3430
• 19 Schoffski P, Awada A, Dumez H, Gil T, Bartholomeus S, Wolter P, Taton M, Fritsch H, Glomb P, Munzert G. A phase I, dose-escalation study of the novel Polo-like kinase inhibitor volasertib (BI 6727) in patients with advanced solid tumours. Eur J Cancer 2012; 48: 179-186
• 20 Ye F, Xui L, Yi J, Zhang W, Zhang DY. Anticancer activity of Scutellaria baicalensis and its potential mechanism. J Altern Complement Med 2002; 8: 567-572
• 21 Ye F, Jiang S, Volshonok H, Wu J, Zhang DY. Molecular mechanism of anti-prostate cancer activity of Scutellaria baicalensis extract. Nutr Cancer 2007; 57: 100-110
• 22 Nan JX, Park EJ, Kim YC, Ko G, Sohn DH. Scutellaria baicalensis inhibits liver fibrosis induced by bile duct ligation or carbon tetrachloride in rats. J Pharm Pharmacol 2002; 54: 555-563
• 23 Shin SB, Woo SU, Lee YJ, Yim H. Comparative analysis of a FRET-based PLK1 kinase assay to identify PLK1 inhibitors for chemotherapy. Anticancer Res 2017; 37: 1177-1183
• 24 Akiyama T, Ishida J, Nakagawa S, Ogawara H, Watanabe S, Itoh N, Shibuya M, Fukami Y. Genistein, a specific inhibitor of tyrosine-specific protein kinases. J Biol Chem 1987; 262: 5592-5595
• 25 Degenhardt Y, Greshock J, Laquerre S, Gilmartin AG, Jing J, Richter M, Zhang X, Bleam M, Halsey W, Hughes A, Moy C, Liu-Sullivan N, Powers S, Bachman K, Jackson J, Weber B, Wooster R. Sensitivity of cancer cells to Plk1 inhibitor GSK461364A is associated with loss of p53 function and chromosome instability. Mol Cancer Ther 2010; 9: 2079-2089
• 26 Guan R, Tapang P, Leverson JD, Albert D, Giranda VL, Luo Y. Small interfering RNA-mediated Polo-like kinase 1 depletion preferentially reduces the survival of p53-defective, oncogenic transformed cells and inhibits tumor growth in animals. Cancer Res 2005; 65: 2698-2704
• 27 Spankuch B, Matthess Y, Knecht R, Zimmer B, Kaufmann M, Strebhardt K. Cancer inhibition in nude mice after systemic application of U6 promoter-driven short hairpin RNAs against PLK1. J Natl Cancer Inst 2004; 96: 862-872
• 28 Steegmaier M, Hoffmann M, Baum A, Lénárt P, Petronczki M, Krssák M, Gürtler U, Garin-Chesa P, Lieb S, Quant J, Grauert M, Adolf GR, Kraut N, Peters JM, Rettig WJ. BI 2536, a potent and selective inhibitor of polo-like kinase 1, inhibits tumor growth in vivo . Curr Biol 2007; 17: 316-322
• 29 Danovi D, Folarin A, Gogolok S, Ender C, Elbatsh AM, Engström PG, Stricker SH, Gagrica S, Georgian A, Yu D, U KP. Harvey KJ, Ferretti P, Paddison PJ, Preston JE, Abbott NJ, Bertone P, Smith A, Pollard SM. A high-content small molecule screen identifies sensitivity of glioblastoma stem cells to inhibition of polo-like kinase 1. PLoS One 2013; 8: e77053
• 30 Choi YO, Song HH, Kim YM, Kang NS, Han SY, Chin YW. c-Met and ALK inhibitory constituents from Scutellaria baicalensis and their ATP binding analyses. Bull Kor Chem Soc 2015; 36: 402-405
• 31 Shin SB, Woo SU, Chin YW, Jang YJ, Yim H. Sensitivity of TP53-mutated cancer cells to the phytoestrogen genistein is associated with direct inhibition of Plk1 activity. J Cell Physiol 2017; 232: 2818-2828