Cancer-Selective Targeting of the NF-κB Survival Pathway with GADD45β/MKK7 Inhibitors
Laura Tornatore, Annamaria Sandomenico, Domenico Raimondo, Caroline Low, Alberto Rocci, Cathy Tralau-Stewart, Daria Capece, Daniel D』Andrea, Marco Bua, Eileen Boyle, Mark van Duin, Pietro Zoppoli, Albert Jaxa-Chamiec, Anil K. Thotakura, Julian Dyson, Brian A. Walker, Antonio Leonardi, Angela Chambery, Christoph Driessen, Pieter Sonneveld, Gareth Morgan, Antonio Palumbo, Anna Tramontano, Amin Rahemtulla, Menotti Ruvo, Guido Franzoso.
Constitutive NF-κB signaling promotes survival in multiple myeloma (MM) and other cancers; however, current NF-κB-targeting strategies lack cancer cell specificity. Here, we identify the interaction between the NF-κB-regulated antiapoptotic factor GADD45β and the JNK kinase MKK7 as a therapeutic target in MM. Using a drug-discovery strategy, we developed DTP3, a D-tripeptide, which disrupts the GADD45β/MKK7 complex, kills MM cells effectively, and, importantly, lacks toxicity to normal cells. DTP3 has similar anticancer potency to the clinical standard, bortezomib, but more than 100-fold higher cancer cell specificity in vitro. Notably, DTP3 ablates myeloma xenografts in mice with no apparent side effects at the effective doses. Hence, cancer-selective targeting of the NF-κB pathway is possible and, at least for myeloma patients, promises a profound benefit.