title: ROS-generating mitochondrial DNA mutations can regulate tumor cell metastasis.
abstract: Mutations in mitochondrial DNA (mtDNA) occur at high frequency in human tumors, but whether these mutations alter tumor cell behavior has been unclear. We used cytoplasmic hybrid (cybrid) technology to replace the endogenous mtDNA in a mouse tumor cell line that was poorly metastatic with mtDNA from a cell line that was highly metastatic, and vice versa. Using assays of metastasis in mice, we found that the recipient tumor cells acquired the metastatic potential of the transferred mtDNA. The mtDNA conferring high metastatic potential contained G13997A and 13885insC mutations in the gene encoding NADH (reduced form of nicotinamide adenine dinucleotide) dehydrogenase subunit 6 (ND6). These mutations produced a deficiency in respiratory complex I activity and were associated with overproduction of reactive oxygen species (ROS). Pretreatment of the highly metastatic tumor cells with ROS scavengers suppressed their metastatic potential in mice. These results indicate that mtDNA mutations can contribute to tumor progression by enhancing the metastatic potential of tumor cells.
authors.affiliation: Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Keizo
authors.initials: K
authors.lastname: Takenaga
authors.forename: Miho
authors.initials: M
authors.lastname: Akimoto
authors.forename: Nobuko
authors.initials: N
authors.lastname: Koshikawa
authors.forename: Aya
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Hirotake
authors.initials: H
authors.lastname: Imanishi
authors.forename: Kazuto
authors.initials: K
authors.lastname: Nakada
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Honma
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Hayashi
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D045744:Cell Line, Tumor; D004272:DNA, Mitochondrial; D004273:DNA, Neoplasm; D042967:Electron Transport Complex I / Q000235:genetics / Q000378:metabolism; D016166:Free Radical Scavengers / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D006822:Hybrid Cells; D051379:Mice; D009154:Mutation; D009245:NADH Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D009362:Neoplasm Metastasis / Q000235:genetics*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D004272:DNA, Mitochondrial; D004273:DNA, Neoplasm; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D009245:NADH Dehydrogenase; C508029:NADH dehydrogenase subunit 6, mouse; D042967:Electron Transport Complex I; D000111:Acetylcysteine