CHD1 Loss Hijacks SREBP2-mediated Cholesterol Biosynthesis to Fuel SPOP-deficient Prostate Cancer and Confers Resistance to Castration

Androgen receptor (AR) is an important driver in the disease progression of castration-resistant prostate cancer (CRPC). Speckle-type BTB/POZ protein (SPOP) mutations stabilize AR and frequently co-occur with the loss of chromodomain helicase DNA-binding protein 1 (CHD1). We generated a new genetically engineered mouse model and prostate cancer cells model containing CHD1 deletion and SPOP mutation to study the underlying mechanism. We found CHD1 loss–induced cholesterol production supplies intratumoral androgen biosynthesis and retains AR transcriptional activity in SPOP-mutated prostate tumors, leading to castration resistance.