title: The predictive effect of overexpressed miR-34a on good survival of cancer patients: a systematic review and meta-analysis.
abstract: BACKGROUND
  MicroRNA-34a (miR-34a) is a potential prognostic factor for survival in patients with several types of cancer according to previous clinical researches. We conducted a systematic review and meta-analysis to summarize the significance of increased miR-34a expression in the prognosis of patients' overall survival.
  
  
  METHODS
  The present systematic review and meta-analysis of 15 researches included 2,597 patients. Overexpression of miR-34a may predict good overall survival ([OS], HR =0.76, 95% confidence interval: 0.55-1.06, P=0.105), but the effect was not significant enough. Subgroup analysis results showed miR-34a was an ideal predictor for digestive system cancer (OS, HR =0.50, 95% confidence interval: 0.25-0.99, P=0.048). The predictive effects of elevated expression of miR-34a on the OS of untreated and treated patients were not of obvious differences.
  
  
  CONCLUSIONS
  This systematic review and meta-analysis showed that miR-34a has a predictive effect on overall survival of patients with digestive system cancer.
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Guorong
authors.initials: G
authors.lastname: Dan
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Jiqing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Nephrology, Xinqiao Hospital, Shapingba District, Chongqing, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Ye
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Huiqin
authors.initials: H
authors.lastname: Sun
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Fan
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Jin
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Department of Nephrology, Xinqiao Hospital, Shapingba District, Chongqing, People's Republic of China.
authors.forename: Fahuan
authors.initials: F
authors.lastname: Yuan
authors.affiliation: Institute of Toxicology, School of Preventive Medicine, The Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Zou
keywords: cancer; meta-analysis; miR-34a; prognosis; systematic review