Researchers point out how targeted shape change affects the stability of proteins Pin1 regulates the stability of the tumor suppressor: if Pin1 is active, p53 is stabilized and protects against proteasomal degradation (left), while inactive Pin1 degrades the tumor suppressor (right). © Siepe / Jentsch / MPI of Biochemistry Read out Cell biologists have clarified how a targeted change in shape affects the stability of proteins that suppress, for example, the formation of tumors in humans (tumor suppressors).