Inhibition of DNA-PKcs enhances radiosensitivity and increases the levels of ATM and ATR in NSCLC cells exposed to carbon ion irradiation

doi:10.3892/ol.2015.3730

	Inhibition of DNA-PKcs enhances radiosensitivity and increases the levels of ATM and ATR in NSCLC cells exposed to carbon ion irradiation
	Yang, Lina 1,2,3; Liu, Yuanyuan2 ; Sun, Chao 2; Yang, Xinrui 1,2; Yang, Zhen 1,2; Ran, Juntao ; Zhang, Qiuning 3; Zhang, Hong2 ; Wang, Xinyu 1; Wang, Xiaohu 1,2,3
刊名	Oncology Letters
	2015-11-01
卷号	10 页码:2856-2864
关键词	ATM ATR carbon ion DNA-PKcs radiosensitivity
ISSN号	1792-1074
DOI	10.3892/ol.2015.3730
英文摘要	Non-small cell lung cancer (NSCLC) exhibits radioresistance to conventional rays, due to its DNA damage repair systems. NSCLC may potentially be sensitized to radiation treatment by reducing those factors that continuously enhance the repair of damaged DNA. In the present study, normal lung fibroblast MRC-5 and lung cancer A549 cells were treated with NU7026 and CGK733, which are inhibitors of the DNA-dependent protein kinase catalytic subunit (PKcs) and ataxia telangiectasia mutated (ATM) and ataxia telangiectasia and Rad3-related (ATR), respectively, followed by exposure to X-rays and carbon ion irradiation. The cytotoxic activity, cell survival rate, DNA damage repair ability, cell cycle arrest and apoptosis rate of the treated cells were analyzed with MTT assay, colony formation assay, immunofluorescence and flow cytometry, respectively. The transcription and translation levels of the ATM, ATR and DNA-PKcs genes were detected by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. The results indicated that the radiosensitivity and DNA repair ability of A549 cells were reduced, and the percentages of apoptotic cells and those arrested at the G(2)/M phase of the cell cycle were significantly increased, following ionizing radiation with inhibitor-pretreatment. The expression levels of ATM, ATR, DNA-PKcs and phosphorylated histone H2AX, a biomarker for DNA double-strand breaks, were all upregulated at the transcriptional or translational level in A549 cells treated with carbon ion irradiation, compared with the control and X-rays-treated cells. In addition, the treatment with 5-50 mu M NU7026 or CGK733 did not produce any obvious cytotoxicity in MRC-5 cells, and the effect of the DNA-PKcs-inhibitor on enhancing the radiosensitivity of A549 cells was stronger than that observed for the ATM and ATR-inhibitor. These findings demonstrated a minor role for ATM and ATR in radiation-induced cell death, since the upregulation of ATM and ATR did not rescue the A549 cells subjected to ionizing irradiation. Therefore, future studies on DNA-PKcs, ATM and ATR may lead to novel specific therapies that supplement general radiotherapy for the treatment of lung cancer.
资助项目	National Laboratory of Heavy Ion Accelerator ; Gansu Province Tumor Hospital ; Central Laboratory of the School of Life Sciences of Lanzhou University (Lanzhou, China) ; National Natural Science Foundation of China (Beijing, China)[81160283]
WOS关键词	DOUBLE-STRAND BREAKS ; IONIZING-RADIATION ; MAMMALIAN-CELLS ; GAMMA-H2AX FOCI ; CANCER STATISTICS ; DAMAGE RESPONSE ; HISTONE H2AX ; LUNG-CANCER ; REPAIR ; RADIORESISTANCE
WOS研究方向	Oncology
语种	英语
出版者	SPANDIDOS PUBL LTD
WOS记录号	WOS:000364324800028
资助机构	National Laboratory of Heavy Ion Accelerator ; Gansu Province Tumor Hospital ; Central Laboratory of the School of Life Sciences of Lanzhou University (Lanzhou, China) ; National Natural Science Foundation of China (Beijing, China)
内容类型	期刊论文
源URL	[http://119.78.100.186/handle/113462/40976]
专题	中国科学院近代物理研究所
通讯作者	Wang, Xinyu
作者单位	1.Lanzhou Univ, Sch Life Sci, Inst Cell Biol, Lanzhou 730000, Gansu, Peoples R China 2.Chinese Acad Sci, Inst Modern Phys, Dept Heavy Ion Radiat Med, Lanzhou 730000, Gansu, Peoples R China 3.Gansu Prov Tumor Hosp, Dept Radiotherapy, Lanzhou 730005, Gansu, Peoples R China
推荐引用方式 GB/T 7714	Yang, Lina,Liu, Yuanyuan,Sun, Chao,et al. Inhibition of DNA-PKcs enhances radiosensitivity and increases the levels of ATM and ATR in NSCLC cells exposed to carbon ion irradiation[J]. Oncology Letters,2015,10:2856-2864.
APA	Yang, Lina.,Liu, Yuanyuan.,Sun, Chao.,Yang, Xinrui.,Yang, Zhen.,...&Wang, Xiaohu.(2015).Inhibition of DNA-PKcs enhances radiosensitivity and increases the levels of ATM and ATR in NSCLC cells exposed to carbon ion irradiation.Oncology Letters,10,2856-2864.
MLA	Yang, Lina,et al."Inhibition of DNA-PKcs enhances radiosensitivity and increases the levels of ATM and ATR in NSCLC cells exposed to carbon ion irradiation".Oncology Letters 10(2015):2856-2864.