Lipid removal from the <10 kDa filtrate with the lipid adsorption reagent (CleanasciteTM) abolished the activity (Supplementary Fig. 3d), suggesting lipid LTB4R2 ligands are released SCD-dependently by aHSC to activate LRB4R2-YAP1 pathway in HCC cells. Here, LTB4R2 is linked to hepatocellular carcinoma.