title: [Effect of protein kinase CK2 gene silencing on radiosensitization in human nasopharyngeal carcinoma cells].
abstract: OBJECTIVE
  To investigate the effect of protein kinase CK2 gene silencing on the radiosensitization in human nasopharyngeal carcinoma (NPC) cells and its possible mechanism.
  
  
  METHODS
  RNA interference (RNAi) technique was used to down-regulate the protein kinase CK2alpha expression in 5-8F cells, and clonogenic assay was employed to observe the changes in the radiosensitivity of the cells. DNA double-strand break was assessed by immunofluorescence staining of gamma-H2AX foci, and the cell apoptosis was examined using Annexin V-FITC/PI double-staining flow cytometry.
  
  
  RESULTS
  CK2alpha protein was successfully silenced by siRNA. CK2alpha knockdown significantly decreased the clonogenic activity and increased the radiosensitivity of the NPC cells. After a 15-min exposure of the cells to 1 Gy radiation, significant difference occurred in the gamma-H2AX foci between CK2alpha knockdown cells and the control cells (P<0.01). CK2alpha silencing significantly increased the cell apoptosis after the exposure (P<0.01).
  
  
  CONCLUSIONS
  Protein kinase CK2 plays an important role in the radiosensitivity of the NPC cells, and suppression of its expression might be a potential therapeutic approach of cancer.
authors.affiliation: Department of Health Management, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. liuli@fimmu.com
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Jin-jin
authors.initials: JJ
authors.lastname: Zou
authors.forename: He-san
authors.initials: HS
authors.lastname: Luo
authors.forename: De-hua
authors.initials: DH
authors.lastname: Wu
mesh_terms: D000818:Animals; D017304:Annexin A5 / Q000378:metabolism; D047390:Casein Kinase II / Q000172:deficiency* / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D006657:Histones / Q000235:genetics; D006801:Humans; D009303:Nasopharyngeal Neoplasms / Q000235:genetics / Q000473:pathology*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D011836:Radiation Tolerance / Q000235:genetics*; D014162:Transfection
chemical_list: D017304:Annexin A5; C468783:H2AX protein, human; D006657:Histones; D034741:RNA, Small Interfering; D047390:Casein Kinase II