A few years ago the Cantley lab published a beautiful  study showing the oxidation (in response to ROS) of a key cysteine residue in PKM2 regulated cancer cell metabolism by promoting the accumulation of NADPH, via the pentose phosphate pathway, and GSH.  A new probe report suggests that the small molecule ML285 protects PKM2 from oxidation, eliminating this feedback regulatory mechanism and resulting in enhanced cell death.