Besides, the treatment of etomoxir could significantly reduce the xenograft growth rate of PIWIL1-overexpressing HCC in mice (Supplementary Fig. S3c), as well as the size of the tumor (Supplementary Fig. S3d), although treating etomoxir may also restrict the tumor growth in wild type HCC. The gene discussed is PIWIL1; the disease is hepatocellular carcinoma.