Ketone drink enhances therapeutic efficacy in prostate cancer by targeting EZH2.

It is well established that EZH2, a lysine methyltransferase, is upregulated in most aggressive cancers, highlighting the importance of EZH2 in cancer progression. Recent research has shown that metabolic reprogramming is pivotal in various biological processes, including cancer. Despite this, evidence of EZH2's role in regulating cancer metabolism remains limited. Our study reveals a negative correlation between EZH2 and HMGCS2, a gene belonging to the HMG-CoA synthase, in prostate and breast cancers. Interestingly, HMGCS2 is inversely related to cancer progression and prognosis in these cancers. Furthermore, HMGCS2 is epigenetically repressed by EZH2 both in vitro and in vivo. Notably, restored EZH2 reduces the elevated HMGCS2 levels observed upon EZH2 depletion. Overexpression of HMGCS2 decreases tumorigenesis in both prostate and breast cancers. Additionally, β-hydroxybutyrate (BHB), a downstream metabolite of HMGCS2, impedes prostate cancer progression by targeting EZH2 via direct protein-compound interaction-mediated protein degradation. More importantly, the ketone drink of BHB administration dramatically reduces tumor size and weight in a therapy-resistant, castration-resistant prostate cancer patient-derived xenograft model. Combining a ketone drink with FDA-approved drugs enzalutamide and Tazemetostat further suppresses tumor progression. Overall, the EZH2-HMGCS2-BHB regulatory network plays a critical role in the progression of prostate cancer, and a ketone drink is a novel therapeutic tool for patients with aggressive prostate cancer.