 PAC-1 was discovered in Professor Paul Hergenrother's laboratory at the University of Illinois at Urbana–Champaign during a process that screened many chemicals for anti-tumor potential.This molecule, when delivered to cancer cells, signals the cells to self-destruct by activating an "executioner" protein, procaspase-3.Then, the activated executioner protein begins a cascade of events that destroys the machinery of the cell.