A new way of blocking enzymes that destroy faulty proteins could fight the blood cancer multiple myeloma.

Proteasomes are enzyme complexes that degrade misfolded proteins, and disrupting them can stop some cancers from proliferating. But cancer cells quickly become resistant to such inhibition, so Thomas Kodadek of the Scripps Research Institute in Jupiter, Florida, and his colleagues targeted a different part of this system to try to avoid resistance. They showed an anti-cancer effect from blocking a receptor called Rpn13, which is present in elevated amounts in cancer cells but is not targeted by traditional proteasome inhibitors. The blocking molecule binds selectively to Rpn13 and is toxic to multiple-myeloma cells.

Their work confirms an earlier report that it is possible to bind a drug-like compound specifically to the Rpn13 receptor.

J. Am. Chem. Soc. http://doi.org/372 (2015)