Effect of Vitamin B 12 -Deficiency in Colon Carcinogenesis

Abstract

Summary

The effect of vitamin B₁₂ deficiency on intestinal carcinogenesis with azoxymethane was studied in male F344 rats. Upon weekly injection of 0.2 mmol/kg body wt of azoxymethane, most of the rats on vitamin B₁₂-deficient diet failed to produce small intestinal or colon tumors, whereas, all of the rats on vitamin B₁₂-deficient diet supplemented with 100 μg/kg vitamin B₁₂ developed adenoma or adenocarcinoma of duodenum or colon. The vitamin B₁₂-adequate diet was more effective in producing colon tumors in F344 rats than mixed commercial diet. It appears that vitamin B₁₂ is necessary for intestinal carcinogenesis with azoxymethane.