Abstract 5980: Cancer therapeutic and prevention strategy targeting mutated mitochondria DNA

Abstract

Abstract As the energy factory for the cell, the mitochondrion, through its role of ATP production by oxidative phosphorylation, can be regarded as the guardian of well regulated cellular metabolism; the integrity of mitochondrial functions, however, is particularly vulnerable in cancer due to the lack of superstructures such as histone and lamina folds to protect the mitochondrial genome from unintended exposure, which consequently elevates risks of mutation. In cancer, mechanisms responsible for enforcing quality control surveillance for identifying and eliminating defective mitochondria are often poorly regulated, and certain uneliminated mitochondrial DNA (mtDNA) mutations and polymorphisms can be advantageous for the proliferation, progression, and metastasis of tumor cells and disseminated into microenvironment cells through extracellular vesicle and tunnel nano tube. Such pathogenic mtDNA aberrations are likely to increase and frequently be homoplasmic in metastatic cancer cells and, intriguingly, in normal cells in the tumor microenvironments as well. Distinct characteristics of these abnormalities in mtDNA may provide a new path for cancer therapy. We recently tested this hypothesis with a few PIP-TPP conjugates targeting mtDNA mutations to induce mutants reduction in heteoplasmic cells or apoptosis in homoplasmic or near homoplasmic cells in vivo model without major adverse effects. This finding reaffirms the feasibility of such a PIP-TPP-based mtDNA-targeting approach for anticancer therapy as well as perhaps cancer risk prevention. However, the absence of known mtDNA mutation hotspots limits the clinical application of somatic mutation-targeted PIP-TPPs. Thus, we designed CCCh-1005-TPP to selectively target a frequent ATP6 gene variant and often oncogenically homoplasmic in the associated with hypertrophic cardiomyopathy, colon, breast and ovarian cancer risk and found its anticancer effect in mouse xenograft models. Here we study preclinical trial of CCCh-1005-TPP, a promising novel anti-cancer agent for clearing abnormal mtDNA by reactivating mitochondrial quality control surveillance of mitophagy. Given those mechanistic insights may provide a promising therapeutic or maybe preventive approach of the pathogenic mtDNA removal in homoplasmic or heteroplasmic cells. Additional caveat is that this strategy may also use not only for cancer but also many other mitochondria related diseases, such as neurodegenerative, diabetic, renal, muscle and hearing loss diseases as well as aging. Citation Format: Hiroki Nagase. Cancer therapeutic and prevention strategy targeting mutated mitochondria DNA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5980.