SIRT4 and hepatocellular carcinoma: SIRT4 deacetylates glycerol O-acyltransferase (GNPAT) (64), expression of which is upregulated and which promotes FA synthesis in HCC cells at the K128 residue, while acetyl-CoA acetyltransferase 1 (ACAT1) (65), which is a mitochondrial enzyme, acetylates GNPAT at K128.