Overall, no significant association was found between the MTHFRC677T polymorphism and colorectal cancer in Asian populations (for T vs. C: OR=1.03; 95% CI= 0.92-1.5; p= 0.64; for TT vs CC: OR=0.88; 95%CI= 0.74-1.04; p= 0.04; for CT vs. CC: OR = 1.02; 95%CI= 0.93-1.12; p=0.59; for TT+ CT vs. CC: OR=1.07; 95%CI= 0.94-1.22; p=0.87).
Our findings indicate that the MTHFR genotype does not change adenoma risk in a manner similar to its effect on colorectal cancer, and does not modify the effect of folate supplementation on metachronous adenoma risk.
We evaluated MTHFR genetic susceptibility and common environmental risk factors in the development of colon and rectal cancer, and assessed the interactions between gene and environmental factors with colorectal cancer in a case-control study in the Indian population.
Relationship of the methylenetetrahydrofolate reductaseC677T polymorphism with microsatellite instability and promoter hypermethylation in sporadic colorectal cancer.
In most studies, MTHFR 677TT (10 studies, >4,000 cases) and 1298CC (four studies, >1,500 cases) are associated with moderately reduced colorectal cancer risk.
Certain common polymorphisms within the MTHFR gene (C677T, A1298C) result in reduced enzymatic activity and have been associated with reduced risk for a variety of cancers such as acute lymphocytic leukemia, lung and colorectal cancer.
This meta-analysis suggests that MTHFRC677T polymorphism is associated with decreased risk of colorectal cancer in East Asians, and MTHFR 677T variant has a protective effect on colorectal cancer.
In summary, this meta-analysis suggests that MTHFRA1298C polymorphism is associated with increased cervical cancer and lymphoma risk in Asians, and MTHFRA1298C polymorphism is associated with decreased colorectal cancer risk in Asians.
Overall homozygosity for MTHFR variant genotypes is associated with a reduced risk of colorectal cancer, the opposite of what might have been expected a priori.
In summary, this meta-analysis suggests that MTHFRC677T polymorphism is associated with increased breast cancer, gastric cancer, and hepatocellular cancer risk in Asians, is associated with increased gastric cancer, multiple myeloma, and NHL risk in Caucasians, is associated with decreased AALL risk in Caucasians, is associated with decreased CALL risk in Asians, is associated with increased breast cancer risk in Asians, is associated with decreased colon cancer risk, and is associated with decreased colorectal cancer risk in male population.
Factor V Leiden (rs6025), prothrombin G20210A (rs1799963), PAI-1 4G/5G (rs1799889), MTHFR 677C>T (rs1801133), fibrinogen gamma 10034C>T (rs2066865), and factor XIII Val34Leu (rs5985) were genotyped in 1,801 patients with colorectal cancer and 1,853 healthy controls from a large German population-based study.
Subjects with the RFC1 80AA genotype in combination with low plasma folate concentrations or the MTHFR 677TT genotype had a reduced risk of colorectal cancer of borderline statistical significance.
Relevance of methylenetetrahydrofolate reductase gene variants C677T and A1298C with response to fluoropyrimidine-based chemotherapy in colorectal cancer: a systematic review and meta-analysis.
Whereas our results do not support an association of high enzyme activity and increased risk of colorectal cancer in general, we can not exclude an association of patients with hereditary disease and the MTHFR 1298A --> C variant.