MtCytb transcripts and mitochondrial morphology as possible markers of breast tumor progression, in murine model subjected to physical exercise

Abstract

Modifications of intracellular signaling pathways in which mitochondria take part are considered an important pathophysiological component when it comes to understanding the carcinogenic process. Changes in the mitochondrial genetic content play an important role in this context, since mitochondrial DNA (mtDNA) is closely related to cell metabolism and overall cell functioning, by encoding sequences related to vital electron transport chain (ETC) components and non-coding RNAs (ncRNAs), which are also related to intracellular communication. In this research project, an experimental animal model of spontaneous breast cancer development, using MMTV-PyMT mice, is going to be used in order to evaluate the expression of both Cytb mitochondrial gene and the long non-coding RNA Cytb (lncCytb), at different stages of the carcinogenic progression. Morphological features of the tumor mitochondria are also going to be studied. The experimental animals are going to be subjected to different aerobic activity regimens, making it possible to compare whether physical exercise impacts or not on both the structure of the mitochondria and the RNA expression patterns of mtDNA, regarding Cytb gene and lncCytb. At the end of this research, it is expected to find different RNA expression and mitochondria patterns that correlate specifically with each of the phases of tumor progression, and also that physical activity impacts, in some way, on the analyzed parameters. (AU)