Targeting CYP4A11: Discovery of Isocyanide-Containing Inhibitors for Triple-Negative Breast Cancer

Cytochrome P450 enzymes of the family 4 are increasingly recognized as key players in cancer progression through the production of pro-tumorigenic lipids. Despite this relevance, selective CYP4 inhibitors remain scarce. Herein, we report the rational, structure-based design of a novel class of CYP4A11 inhibitors featuring an isocyanide warhead at the ω-position of fatty acid analogs. This underexplored functional group enables direct and selective coordination with the heme iron, conferring potent inhibition of CYP4A11 (compound 51, IC₅₀ = 45 nM) with minimal off-target activity on major hepatic CYPs. Biochemical, spectroscopic, and kinetic analyses validate the binding mode and specificity of our lead compound. In breast cancer models, 51 selectively impaired cancer stem cell (CSC) populations, reducing spheroid formation, clonal expansion, stemness markers, and cell migration in 3D cultures. Its high metabolic stability and effective prodrug conversion support its therapeutic potential in CSC-targeted cancer therapy and, more generally, as a chemical blueprint for a new generation of selective CYP4 inhibitors.