Copyright ©2009 The WJG Press and Baishideng.
World J Gastroenterol. Jan 21, 2009; 15(3): 257-263
Published online Jan 21, 2009. doi: 10.3748/wjg.15.257
Figure 1
Figure 1 Folate, in the form of methyltetrahydrofolate (methyl-THF), is involved in remethylation of homocysteine to methionine, which is a precursor of SAM, the primary methyl group donor for most biological methylation reactions, also in DNA[64]. Folate deficiency may thus enhance CRC through an induction of genomic DNA hypomethylation. Expression of several enzymes (GHMT, MTHFR, BHMT, MAT, SAHH, CBS) involved in methyl metabolism can be regulated by diet such as availability of nutrients including essential amino acids, vitamins B2, B6 and B12, and Zinc (Zn).