title: The relationship between altered mitochondrial DNA copy number and cancer risk: a meta-analysis.
abstract: Currently, a comprehensive assessment between mitochondrial DNA (mtDNA) content and cancer risk is lacking. We designed this meta-analysis to test the hypothesis that altered mtDNA copy number might influence genetic susceptibility to some specific types of cancer. The processes of literature search, eligibility appraisal and data retrieval were independently completed in duplicate. The mtDNA copy number which was dichotomized or classified into tertiles was compared between cancer cases and controls. Twenty-six articles with 38 study groups were analyzed among 6682 cases and 9923 controls. When dichotomizing mtDNA copy number at the median value, there was an 11% increased cancer risk for carriers of high mtDNA content (P = 0.320). By cancer type, high mtDNA content was associated with an increased risk for lymphoma (OR = 1.76; P = 0.023) but a reduced risk for skeleton cancer (OR = 0.39; P = 0.001). Carriers of the 2(nd) and 3(rd) tertiles of mtDNA copy number had an 1.74-fold (P = 0.010) and 2.07-fold (P = 0.021) increased risk of lymphoma, respectively. By contrast, there was correspondingly a 56% (P < 0.001) and 80% (P < 0.001) reduced risk of skeleton cancer. Our findings suggested that elevated mtDNA content was associated with a higher risk for lymphoma, but a lower risk for skeleton cancer.
authors.affiliation: Medicine and Pharmacy Research Center.
authors.forename: Jia
authors.initials: J
authors.lastname: Mi
authors.affiliation: Medicine and Pharmacy Research Center.
authors.forename: Geng
authors.initials: G
authors.lastname: Tian
authors.affiliation: Medicine and Pharmacy Research Center.
authors.forename: Shuang
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Clinical Medicine.
authors.forename: Xianglin
authors.initials: X
authors.lastname: Li
authors.affiliation: Basic Medical Department.
authors.forename: Tianhui
authors.initials: T
authors.lastname: Ni
authors.affiliation: Yantai Affiliated Hospital.
authors.forename: Liwei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Institute of Molecular Imaging, Binzhou Medical University, Yantai, Shandong, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
mesh_terms: D016022:Case-Control Studies; D056915:DNA Copy Number Variations; D004272:DNA, Mitochondrial; D018628:Gene Dosage; D020022:Genetic Predisposition to Disease; D006801:Humans; D009369:Neoplasms / Q000235:genetics*; D016017:Odds Ratio; D012306:Risk
chemical_list: D004272:DNA, Mitochondrial