title: Association of leukocyte mitochondrial DNA content with glioma risk: evidence from a Chinese case-control study.
abstract: BACKGROUND
  Increasing evidence suggests that alterations in mitochondrial DNA (mtDNA) content may be implicated in the tumorigenesis of several malignancies. However, the association between mtDNA content in peripheral blood lymphocytes (PBLs) and glioma risk has not been investigated.
  
  
  METHODS
  Real-time PCR was used to examine the mtDNA content in PBLs of 414 glioma patients and 414 matched controls in a hospital-based case-control study. The association between mtDNA content and glioma risk was evaluated using an unconditional multivariate logistic regression model.
  
  
  RESULTS
  We found that glioma patients exhibited a significantly higher median mtDNA content than healthy controls (0.99 vs. 0.71, P < 0.001). Unconditional multivariate logistic regression analysis adjusting for age, gender, smoking status, and family cancer history showed that there was an S-shaped association between mtDNA content and glioma risk. Higher mtDNA content was significantly associated with an elevated risk of glioma. Compared with the first quartile, the odds ratio (95% confidence interval) for subjects in the second, third, and fourth quartiles of mtDNA content were 0.90 (0.52-1.53), 3.38 (2.15-5.31), and 5.81 (3.74-9.03), respectively (P for nonlinearity = 0.009). Stratified analysis showed that the association between mtDNA content and glioma risk was not modulated by major host characteristics.
  
  
  CONCLUSIONS
  Our findings demonstrate for the first time that a higher mtDNA content in PBLs is associated with an elevated risk of glioma, which warrants further investigation in larger populations.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Deyang
authors.initials: D
authors.lastname: Li
authors.forename: Falin
authors.initials: F
authors.lastname: Qu
authors.forename: Yibing
authors.initials: Y
authors.lastname: Chen
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.forename: Hequn
authors.initials: H
authors.lastname: Jiang
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Huang
authors.forename: Hushan
authors.initials: H
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Cancer Biology & Experimental Teaching Center of Basic Medicine, Fourth Military Medical University, Xi'an 710032, China. xingjinliang@163.com.
authors.forename: Jinliang
authors.initials: J
authors.lastname: Xing
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics*; D014408:Biomarkers, Tumor / Q000235:genetics*; D016022:Case-Control Studies; D002681:China; D056915:DNA Copy Number Variations; D004272:DNA, Mitochondrial / Q000097:blood* / Q000235:genetics*; D005260:Female; D005910:Glioma / Q000097:blood* / Q000235:genetics; D006801:Humans; D007962:Leukocytes / Q000378:metabolism; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060888:Real-Time Polymerase Chain Reaction; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; D004272:DNA, Mitochondrial