The effect of ionizing radiation on the subcellular localization and kinase activity of protein kinase CK2 in human non-small cell lung cancer cells

Abstract

Protein kinase CK2 is a ubiquitously expressed kinase in eukaryotes, which is known to phosphorylate many protein substrates. Because CK2 is involved in the regulation of various signaling pathways, we wondered whether CK2 participated in the regulation of ionizing radiation (IR) induced biological process. In this study, we investigated the effect of IR on the subcellular localization and kinase activity in human non-small cell lung cancer (NSCLC) cells. Immunofluorescent results showed that CK2 subunits shuttle into the nucleus mostly beginning 1 h after IR and lasting more than 6 h. We also conducted in vitro kinase assay and observed an increase in CK2 kinase activity at 6 h after IR. Furthermore, an increase in S phase was observed at 6 h after IR. Colony formation assay results demonstrated that CK2 inhibitor CX-4945 significantly enhanced the effect of irradiation in NSCLC cells. These results indicated that CK2 may be implicated in the regulation of IR-induced biological process.

Keywords:

• Protein kinase CK2
• ionizing radiation
• non-small cell lung cancer

Acknowledgement

We sincerely thank Prof. Dr. Mathias Montenarh from Medizinische Biochemie und Molekularbiologie, Universität des Saarlandes, Germany for his time, support, and valuable suggestions throughout the development of this paper.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This research was supported by National Nature Science Foundation of China for Young Scholar [NSFC, No. 81101690], Natural Science Foundation of Hubei Province of China [NO. 2016cfb426], Wuhan Key Talent Training Project (2016), and Applied Basic Research Foundation of Wuhan Science and Technology Committee [NO. 2014060101010034].

Notes on contributors

Qianwen Li

Qianwen Li, PhD, Physician in Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Ke Li

Ke Li, PhD, Pharmacist in Pharmacy Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Sheng Zhang

Sheng Zhang, PhD, Associate Chief Physician & Associate Professor, Director of Radiation Oncology Department of Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Yu Zhou

Yu Zhou, Technologist of Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Jiaxin Hong

Jiaxin Hong, PhD, Physician in Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Xiaoshu Zhou

Xiaoshu Zhou, PhD, Physician in Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Zhenyu Li

Zhenyu Li, PhD, Physician in Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Bian Wu

Bian Wu, PhD, Physician in Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Gang Wu

Gang Wu, PhD, Chief Physician & Professor, Director of Oncology Department of Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.

Rui Meng

Rui Meng, MD, PhD, Associate Chief Physician & Associate Professor, Deputy Director of Thoracic Oncology Department of Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology.