Maternal supplementation with vitamins B₂, B₆, B₁₂ and folate led to a lower incidence of small intestinal tumours in mice offspring than those whose mothers had received no supplementation and those whose mothers were deficient in the vitamins, reports a study in Gut.

Epidemiological data and animal studies have suggested a protective role for dietary folate and related B vitamins against colorectal cancer. The critical importance of exposure timing promoted Jimmy Crott and colleagues from Tufts University (Boston, Massachusetts, USA) to consider exposure during foetal life. Maternal diet and environmental exposure, the authors write, is becoming recognised as an increasingly important determinant of the risk of chronic disease in offspring.

In the current study Crott and colleagues fed female wildtype mice diets mildly deficient, replete or supplemented with vitamins B₂, B₆, B₁₂ and folate for four weeks prior to mating. The females remained on their diets throughout pregnancy and until weaning.

Results at 8 months showed that the tumour incidence among the offspring off supplemented mothers was 21%, compared with 59% for mothers who did not undergo supplementation and 55% for those whose mothers were deficient (p=0.03). Furthermore, the results showed that tumours arising in the offspring of deficient mothers were more likely to be invasive (p=0.03).

The investigators also found that the expression of Apc, Sfrp1, Wif1 and Wnt5a, (all of which are negative regulatory elements of the Wnt signalling cascade), were decreased in the small intestinal mucosa of offspring whose mothers had no supplementation. This data, say the authors, indicates a plausible mechanism whereby maternal B vitamin intakes could be modulating tumour growth in offspring.

"These data indicate that maternal B vitamin supplementation may not only protect offspring against birth defects but also against colorectal cancer in adulthood," wrote the authors, adding that mild deficiencies of vitamins B₂, B₆ and B₁₂ persist in 10 to 50% of the populations of industrialised nations wrote the authors.

Reference

E D Ciappio, Z Liu, R S Brooks, et al. Maternal B vitamin supplementation from preconception through weaning suppresses intestinal tumorigenesis in Apc 1638N mouse offspring, Gut Doi: 10.1136/gut.2011.240291