FASN and hepatocellular carcinoma: TRIM21 inhibits fatty acid (FA) synthesis by ubiquitination and degradation of fatty acid synthase (FASN) in hepatocellular carcinoma [8], and further studies found that the ubiquitination of FASN by TRIM21 could be inhibited by glyceronephosphate O-acyltransferase (GNPAT) [9].