P5091 is primarily used in research settings to study the mechanisms of protein degradation, particularly through the ubiquitin-proteasome pathway. It acts as an inhibitor of USP7, a deubiquitinating enzyme, making it valuable in understanding the role of USP7 in cellular processes such as DNA repair, apoptosis, and tumor suppression. This compound is often utilized in cancer research to explore its potential in targeting cancer cells, as USP7 is known to regulate key tumor suppressors like p53. By inhibiting USP7, P5091 can help researchers investigate its effects on cell cycle regulation and cancer cell survival. Additionally, it is used in biochemical assays to study protein-protein interactions and ubiquitin dynamics, providing insights into disease mechanisms and potential therapeutic strategies.