To investigate the role of YY1 in regulating HCC cell lipid metabolism under hypoxic condition, we knocked down YY1 expression in the HCC cell lines HepG2 and MHCC-97H using short-hairpin RNAs (shRNAs), and confirmed that both shYY1 vectors efficiently knocked down YY1 mRNA expression (Figure S1B). This evidence concerns the gene YY1 and hepatocellular carcinoma.