Metabolism and Cancer: Let’s Not ROS to Judgment

by Nicholas Maxwell and Kylie Woodley
Faculty advisor: Dr. Brian Lenzmeier

Scientists have speculated that Reactive oxygen species (ROS) created during normal metabolism in the mitochondria might be linked to cancer. Although ROS have been experimentally demonstrated to cause damage to mitochondrial DNA, the connection between ROS made in the mitochondria and nuclear DNA damage has been primarily speculative in nature. We are using the Baker’s Yeast Saccharomyces cerevisiae to study directly the effects of reactive oxygen species (ROS) on nuclear DNA. Using a genetic assay, we are determining nuclear chromosome breakage rates under two conditions that involve changes in ROS levels. First, we are exposing yeast cells to paraquat, which is a chemical that increases ROS formation in the mitochondria. Second, we are exposing yeast cells to high levels of the amino acid proline, which our lab has shown to decrease ROS levels and promote cell survival in the presence of peroxide and paraquat. We will present our preliminary findings for these experiments and hope that our research more directly addresses the question of whether or not ROS generated by the mitochondria are causing the type of DNA damage events in the nucleus that are associated with cancer.