title: miR-34b inhibits nasopharyngeal carcinoma cell proliferation by targeting ubiquitin-specific peptidase 22.
abstract: OBJECTIVE
  This study aimed to investigate the precise role of miR-34b in nasopharyngeal carcinoma (NPC).
  
  
  METHODS
  The expression of miR-34b and transcription of ubiquitin-specific peptidase 22 (USP22) were examined using quantitative reverse transcription-polymerase chain reaction. Western blot analysis was used to measure the protein expression of USP22. A dualluciferase assay was used to investigate the interaction between miR-34b and USP22. Cell viability was determined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. The cell cycle was analyzed by propidium iodide staining followed by flow cytometry analysis.
  
  
  RESULTS
  miR-34b was significantly downregulated in NPC tissues and NPC cell lines. Overexpression of miR-34b in NPC SUNE-6-10B cells inhibited cell viability and proliferation. USP22 was highly expressed in NPC cells and promoted cell viability and proliferation. Restoration of USP22 expression could reverse the effect of miR-34b on NPC cell viability and proliferation.
  
  
  CONCLUSIONS
  miR-34b acts as a tumor suppressor in NPC, which is mediated via repression of the oncogene USP22.
authors.affiliation: Department of Biochemistry, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Jianyong
authors.initials: J
authors.lastname: Xiao
authors.affiliation: Department of Internal Medicine, Guangzhou Eighth People's Hospital, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Biochemistry, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Wenyin
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Yanni
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Department of Pathology, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Biaoyan
authors.initials: B
authors.lastname: Du
authors.affiliation: Department of Biochemistry, Guangzhou University of Chinese Medicine, Guangzhou, People's Republic of China.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Tan
keywords: USP22; cell proliferation; miR-34b; nasopharyngeal carcinoma; overexpression