Our data showed 3-hydroxyanthranilic acid (3-HAA), a structural analog of kynurenine, was reduced in HCC cells and exogenous 3-HAA enhanced apoptosis in HCC (Shi, et al. Kynurenine derivative 3-HAA is an agonist ligand for transcript factor YY1). This evidence concerns the gene YY1 and hepatocellular carcinoma.