Inadequate dietary intake of methyl groups leads to
hypomethylation in many important pathways, including 1) disturbed hepatic protein (methionine) metabolism as determined by elevated plasma homocysteine concentrations and decreased S - adenosylmethionine concentrations, and 2) inadequate hepatic fat metabolism, which leads to steatosis (fatty accumulation) and subsequent plasma dyslipidemia.
However, he did not mention that we also know that
hypomethylation in DNA synthesis, which can occur with inadequate folate intake, can also cause DNA synthesis errors and chromosome breakage, which can initiate cancer formation.
This unbiased approach revealed global
hypomethylation in the cancer cell line (HCC1954) relative to epithelial cells (HMEC), and some specific patterns:
Veland N, Hardikar S, Zhong Y, Gayatri S, Dan J, Strahl BD, Rothbart SB, Bedford MT, Chen T. (2017) The Arginine Methyltransferase PRMT6 Regulates DNA Methylation and Contributes to Global DNA
Hypomethylation in Cancer.
Not exact matches
Such epigenetic mechanisms have already been exploited for diagnosis and treatment; for example, DNA
hypomethylation therapy with 5 - azacytidine is approved for MDS and is
in clinical trials for some other cancers.
In regions of DNA
hypomethylation, H3K27me3 and H3K9me3 form repressive chromatin domains.
Global DNA
hypomethylation coupled to repressive chromatin domain formation and gene silencing
in breast cancer Genome Research, 22 (2), 246 - 258 DOI: 10.1101 / gr.125872.111
The authors looked at gene expression
in a panel of 50 ERBB2 (Her2) positive breast tumors and found that this pattern held up: DNA
hypomethylation is associated with decreased gene expression
in breast cancer.
Non-CpG island promoter
hypomethylation and miR - 149 regulate the expression of SRPX2
in colorectal cancer.
12:30 PM Defects of the maintenance methyltransferase DNMT1 lead to progressive neurological phenotypes
in association with global
hypomethylation.