Association of Dietary Intake of Folate, Vitamin B6 and B12 and MTHFR Genotype with Breast Cancer Risk

Aim: We aimed to investigate the associations of dietary intake of folate, vitamin B6 and B12 and MTHFRgenotype with breast cancer in a Chinese population.
Methods: A matched case-control study was conducted, and435 patients with newly diagnosed and histologically confirmed breast cancer and 435 controls were collected. Thefolate intake, vitamin B6 and vitamin B12 were calculated, and MTHFR C665T, C677T and A1298C were analyzedby PCR-RFLP.
Results: We found vitamin B12 was likely to reduce the risk of breast cancer, and MTHFR 665TTwas associated with increased risk of breast cancer. Folate intake, vitamin B12 intake and variants of MTHFRC677T and MTHFR A1298C demonstrated no association with risk of breast cancer. However, we found patientswith low intake of vitamin B6 and MTHFR 665TT genotype had a higher risk of breast cancer (OR=1.87, 95%CI=1.29-2.77), the association being less pronounced among subjects with a moderate intake of vitamin B6 andMTHFR 665TT genotype (OR=1.58, 95% CI=1.03-2.49, P=0.03).
Conclusion: Our study indicated that theMTHFR C665T polymorphism and vitamin B6 are associated with risk of breast cancer, which indicated rolesfor nutrients in developing breast cancer.