The work, led by Hermann Steller, Strang Professor and head of the Laboratory of Apoptosis and Cancer Biology, is the first to reveal the mechanism by which a class of proteins called IAPs regulates cell death. By exposing the mechanism in a living animal, the finding also marks a breakthrough in the field and opens the door for developing a new class of drugs that could aid in cancer therapy and prevention.

“In a way, these mice are guiding clinical trials,” says Steller, who is also a Howard Hughes Medical Institute investigator. “We now can study how IAPs contribute to the development of cancer in a living animal and develop drugs to prevent or thwart the disease.”

IAP stands for “inhibitor of apoptosis protein,” and these proteins do exactly what their name implies. By inhibiting apoptosis, or programmed cell death, they keep cells alive by directly binding to executioner enzymes called caspases. But until now, precisely how IAPs save cells from death has remained unclear.