Multivalent DR5 peptides activate the TRAIL death pathway and exert tumoricidal activity.

Abstract Ongoing clinical trials are exploring anticancer approaches based on signaling by TRAIL, a ligand for the cell death receptors DR4 and DR5. In this study, we report on the selective apoptotic effects of multivalent DR5 binding peptides (TRAILmim/DR5) on cancer cells in vitro and in vivo. Surface plasmon resonance revealed up to several thousand-fold increased affinities of TRAILmim/DR5-receptor complexes on generation of divalent and trivalent molecules, the latter of which was achieved with a conformationally restricted adamantane core. Notably, only multivalent molecules triggered a substantial DR5-dependent apoptotic response in vitro. In tumor models derived from human embryoni…