alexa Mitochondrial mutations in cancer.


Immunotherapy: Open Access

Author(s): Brandon M, Baldi P, Wallace DC, Brandon M, Baldi P, Wallace DC, Brandon M, Baldi P, Wallace DC, Brandon M, Baldi P, Wallace DC

Abstract Share this page

Abstract The metabolism of solid tumors is associated with high lactate production while growing in oxygen (aerobic glycolysis) suggesting that tumors may have defects in mitochondrial function. The mitochondria produce cellular energy by oxidative phosphorylation (OXPHOS), generate reactive oxygen species (ROS) as a by-product, and regulate apoptosis via the mitochondrial permeability transition pore (mtPTP). The mitochondria are assembled from both nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) genes. The mtDNA codes for 37 genes essential of OXPHOS, is present in thousands of copies per cell, and has a very high mutations rate. In humans, severe mtDNA mutations result in multisystem disease, while some functional population-specific polymorphisms appear to have permitted humans to adapt to new environments. Mutations in the nDNA-encoded mitochondrial genes for fumarate hydratase and succinate dehydrogenase have been linked to uterine leiomyomas and paragangliomas, and cancer cells have been shown to induce hexokinase II which harnesses OXPHOS adenosine triphosphate (ATP) production to drive glycolysis. Germline mtDNA mutations at nucleotides 10398 and 16189 have been associated with breast cancer and endometrial cancer. Tumor mtDNA somatic mutations range from severe insertion-deletion and chain termination mutations to mild missense mutations. Surprisingly, of the 190 tumor-specific somatic mtDNA mutations reported, 72\% are also mtDNA sequence variants found in the general population. These include 52\% of the tumor somatic mRNA missense mutations, 83\% of the tRNA mutations, 38\% of the rRNA mutations, and 85\% of the control region mutations. Some associations might reflect mtDNA sequencing errors, but analysis of several of the tumor-specific somatic missense mutations with population counterparts appear legitimate. Therefore, mtDNA mutations in tumors may fall into two main classes: (1) severe mutations that inhibit OXPHOS, increase ROS production and promote tumor cell proliferation and (2) milder mutations that may permit tumors to adapt to new environments. The former may be lost during subsequent tumor oxygenation while the latter may become fixed. Hence, mitochondrial dysfunction does appear to be a factor in cancer etiology, an insight that may suggest new approaches for diagnosis and treatment. This article was published in Oncogene and referenced in Immunotherapy: Open Access

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version