title: Quantitative analysis of mitochondrial DNA 4977-bp deletion in sporadic breast cancer and benign breast diseases.
abstract: The mitochondrial DNA (mtDNA) 4977-bp deletion (DeltamtDNA(4977) mutation) is one of the most frequently observed mtDNA mutations in human tissues and may play a role in carcinogenesis. Only a few studies have evaluated DeltamtDNA(4977) mutation in breast cancer tissue, and the findings have been inconsistent, which may be due to methodological differences. In this study, we developed a quantitative real-time PCR assay to assess the level of the DeltamtDNA(4977) mutation in tumor tissue samples from 55 primary breast cancer patients and 21 patients with benign breast disease (BBD). The DeltamtDNA(4977) mutation was detected in all of the samples with levels varying from 0.000149% to 7.0%. The DeltamtDNA(4977) mutation levels were lower in tumor tissues than in adjacent normal tissues in both breast cancer and BBD subjects. The differences, however, were not statistically significant. No significant difference between breast cancer and BBD patients was found in the DeltamtDNA(4977) mutation levels of tumor tissues and adjacent normal tissues. The DeltamtDNA(4977) mutation levels were not significantly associated with clinicopathological characteristics (age, histology, tumor stage, and ER/PR status) in breast cancer or BBD patients. These results do not support the notion that the mitochondrial DNA 4977-bp deletion plays a major role in breast carcinogenesis.
authors.affiliation: Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt University School of Medicine and Vanderbilt Ingram-Cancer Center, Nashville, TN 37232, USA.
authors.forename: Chuanzhong
authors.initials: C
authors.lastname: Ye
authors.forename: Xiao-Ou
authors.initials: XO
authors.lastname: Shu
authors.forename: Wanqing
authors.initials: W
authors.lastname: Wen
authors.forename: Larry
authors.initials: L
authors.lastname: Pierce
authors.forename: Regina
authors.initials: R
authors.lastname: Courtney
authors.forename: Yu-Tang
authors.initials: YT
authors.lastname: Gao
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.forename: Qiuyin
authors.initials: Q
authors.lastname: Cai
mesh_terms: D001941:Breast Diseases / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000379:methods*; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D017384:Sequence Deletion
chemical_list: D004272:DNA, Mitochondrial