PAC-1 is primarily used in cancer research due to its ability to activate procaspase-3, a protein involved in triggering apoptosis (programmed cell death) in damaged or abnormal cells. Many cancer cells evade apoptosis by keeping procaspase-3 in an inactive state, allowing uncontrolled growth. PAC-1 restores the activity of procaspase-3, promoting cell death in tumor cells. It has shown promising results in preclinical studies against various cancers, including melanoma, neuroblastoma, and certain types of leukemia. Researchers are exploring its use both as a standalone agent and in combination with other therapies to enhance cancer cell killing. Due to its mechanism, PAC-1 represents a novel approach in anticancer drug development, focusing on reactivating the body’s natural cell death pathways rather than directly damaging cancer cells.