SMIP-016 in action: CD37 as a death receptor.

CD37 is a tetraspannin that triggers cell death and is a potential therapeutic target in cancers. In this issue of Cancer Cell, Lapalombella et al. show that CD37 is tyrosine phosphorylated following engagement by a bivalent engineered antibody fragment that binds CD37 and activates both SHP-1-dependent apoptotic signaling and PI3K-AKT-mediated survival signaling.