Symmetric naphthoflavone degraders clear CYP1B1 and boost anti-PD-L1 response in colon tumor models
- Two copies of an α-naphthoflavone CYP1B1 ligand flank a PEG linker, so whichever end is not bound in the active site can act as a hydrophobic degradation tag.
- The lead degrades CYP1B1 selectively over CYP1A1 with no hook effect, through misfolding, HSP70/HSP90 recruitment and proteasomal clearance.
- At a low dose it synergized with anti-PD-L1 in colon tumor models; a CDK4/6 degrader using the same tag hints at wider use.
💡 Points Based on the abstract
The symmetric design is neat, but the second ligand roughly doubles molecular weight and lipophilicity, so I'd worry about solubility, permeability and in vivo exposure before efficacy. Hydrophobic tags usually give only partial depletion compared with VHL/CRBN PROTACs. The missing controls are a CYP1B1 PROTAC at matched dose and the parent inhibitor, to separate degradation from enzymatic inhibition.