Metabolic profiling of fatty acid derived from PIWIL1-overexpressing tumors suggested an increased C16 intermediate compared with that from wild type tumors (Fig. 2h).27 FAO assay using oleate as a substrate further confirmed that PIWIL1 could promote fatty acid metabolism in HCC cells (Supplementary Fig. S2g). Here, PIWIL1 is linked to hepatocellular carcinoma.