The influence of one-carbon metabolism on gene promoter methylation in a population-based breast cancer study

Figures & data

Figure 1 Example of epigenetically active micro-nutrients for association between gene promoter methylation status and dietary intake of one-carbon related nutrients. Odd ratios (ORs) and 95% confidence intervals are shown on the y-axis, comparing medium and high intake to the low intake group. p values are of the test for liner trend of ORs.

Figure 2 Example of dietary sensitive genes for association between gene promoter methylation status and dietary intake one-carbon related nutrients. Odds ratios and 95% confidence intervals were shown on the y-axis, comparing medium and high intake to the low intake group. p values are of the test for liner trend of ORs.

Table 1 Genes selected for methylation analysis and their putative functions

Gene	Full name	Group	Function	Assayed sample no.	Methylated samples (%)
ESR1	estrogen receptor 1	steroid hormone receptor	hormone binding, DNA binding and activation of transcription	851	44.8
PGR	progesterone receptor	steroid hormone receptor	mediates the physiological effects of progesterone	851	11.9
BRCA1	breast cancer 1, early onset	tumor suppressor	maintaining genomic stability	851	59.0
APC	adenomatous polyposis coli	tumor suppressor	an antagonist of the Wnt signaling; Defects cause familial adenomatous polyposis	800	48.4
p16/CDKN2A	cyclin-dependent kinase inhibitor 2A	tumor suppressor	cell cycle control	777	3.6
HIN1/SCGB3A1	secretoglobin, family 3A, member 1	tumor suppressor	growth-inhibitory cytokine, regulates epizthelial cell differentiation.	765	62.9
RASSF1A	Ras association domain family member 1	tumor suppressor	involved in cell cycle control	765	85.2
DAPK1	death-associated protein kinase 1	tumor suppressor	a positive mediator of gamma-interferon induced programmed cell death	765	14.1
GSTP1	glutathione S-transferase pi 1	detoxification	xenobiotic metabolism	765	27.8
CCND2	cyclin D2	oncogene	regulators of CDK kinases	765	19.6
TWIST1	twist homolog 1	transcription factors	cell lineage determination and differentiation	765	15.3
CDH1	E-cadherin	tumor suppressor	cell proliferation, invasion and/or metastasis	765	5.8
RARβ	retinoic acid receptor, beta	steroid hormone receptor	mediates cellular signalling in embryonic morphogenesis, cell growth and differentiation	765	27.6

Table 2 Summary of significant trends between one-carbon micronutrient intake and gene promoter methylation status

_↑ indicates positive association, i.e., higher intake is associated with higher likelihood for a case to possess a methylated promoter for the gene of interest; _↓ indicates inverse association, i.e., higher intake is associated with lower likelihood for a case to possess a methylated promoter for the gene of interest. Cells without an arrow are those with insignificant trend test results.