This Master's thesis explores the important relationship between cancer metabolism and genome stability. Specifically, the research investigates how the IDO1 enzyme influences the regulation of R-loops, which are unique DNA-RNA structures that can affect overall DNA stability. To test the hypothesis, laboratory experiments were conducted using two different breast cancer cell lines. These cells were analyzed using a combination of global R-loop detection and a specialized molecular technique called DRIP-qPCR. The findings provide new and meaningful insights into how IDO1-related metabolic pathways impact the genome. Overall, this study builds a solid foundation for future research aiming to better understand the underlying biology of cancer.