PEMT and hepatocellular carcinoma: The elevation of PE and LPE and reduction of PC and LPC levels in our metabolomics and lipidomics studies could be due to the reduced expression of PE N-methyltransferase 2 (PEMT2) enzyme which catalyzes the conversion of PE to PC in the liver when dietary choline supply is low and found to be reduced or missing in HCC [25,38].