Lysophosphatidylethanolamine 18:1 drives clear cell renal cell carcinoma by stabilizing SIRT6 to reprogram lipid metabolism

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.