Bassett JK, et al. - In view of the involvement of B-group vitamins, as components of the one carbon metabolism pathway, in DNA synthesis, repair and methylation, researchers investigated how circulating plasma levels of B vitamins are associated with urothelial cell carcinoma (UCC). For this purpose, a nested case–control study of UCC was conducted within the Melbourne Collaborative Cohort Study. Outcomes revealed no strong associations between UCC risk and pre-diagnostic levels of plasma B vitamins. In UCC risk, they noted No heterogeneity by subtype (invasive or superficial), sex, smoking status or alcohol intake. No heterogeneity by country of birth for most B vitamins, except for folate, was observed.