An AKT2-specific nanobody that targets the hydrophobic motif induces cell cycle arrest, autophagy and loss of focal adhesions in MDA-MB-231 cells

The AKT kinase family is a high-profile target for cancer therapy. Despite their high degree of homology the three isoforms (AKT1, AKT2 and AKT3) are non-redundant can even have opposing functions. Small-molecule inhibitors affect all which severely limits usefulness as research tool or therapeutic. Using AKT2-specific nanobodies we examined function endogenous in breast cells. Two (Nb8 Nb9) modulate reduce MDA-MB-231 cell viability/proliferation. Nb8 binds hydrophobic motif reduces IGF-1-induced phosphorylation this site. This nanobody also affects and/or expression levels wide range proteins downstream AKT, resulting G0/G1 cycle arrest, induction autophagy, reduction focal adhesion count loss stress fibers. While progression likely to be regulated by more than one isoform, our results indicate that both effects on autophagy cytoskeleton specific AKT2. By using an isoform-specific were able map part pathway. Our confirm targets used study signalling events aid design inhibitor.