Clear cell renal cell carcinoma (ccRCC) is characterized by profound lipid metabolic dysregulation, yet the mechanisms linking peritumoral adipose tissue (PAT)-derived lipid metabolites to tumor aggressiveness remain poorly defined. Here, we identified lysophosphatidylethanolamine 18:1 (LPE18:1), a lipid metabolite enriched in PAT and the arterial blood of ccRCC patients, as a critical driver of tumor growth and lipid deposition. Through multiomics analyses and functional studies, we demonstrated that LPE18:1 upregulates F-actin-capping protein subunit alpha-1 (CAPZA1), which recruits ubiquitin-specific peptidase 48 (USP48) to stabilize the NAD-dependent protein deacetylase sirtuin-6 (SIRT6) by inhibiting its proteasomal degradation. Increased SIRT6 epigenetically promotes acetyl-CoA acetyltransferase 2 (ACAT2) expression, redirecting lipid metabolism toward free cholesterol accumulation-a hallmark of ccRCC aggressiveness. Clinically, CAPZA1 and SIRT6 levels correlate with advanced tumor stage and poor prognosis in ccRCC cohorts. Genetic or pharmacological inhibition of the CAPZA1/SIRT6 axis can reverse LPE18:1-induced lipid deposition and tumor progression in xenograft models. Notably, targeting this axis with the SIRT6 inhibitor OSS-128167 combined with CAPZA1 depletion significantly suppresses ccRCC cell growth. Our study reveals a PAT-derived lipid metabolite-fuelled signaling cascade that reprograms lipid metabolism in ccRCC, identifying CAPZA1/USP48/SIRT6 as actionable therapeutic targets for metabolic malignancies.
© 2025. The Author(s).