Role of flavonoids and vitamins in cancer.

Flavonoids are naturally occurring polyphenolic plant compounds that are capable of inhibiting histamine and cytokine release from several cells. Many studies suggest that flavonoids are anticancer agents with an apoptotic effect on tumor cells. Studies with animal tumour models have found vitamin deficiency to enhance susceptibility to chemical carcinogenesis and large doses of anti-oxidant vitamins and flavonoids to inhibit carcinogenesis. In some studies flavonoids and/or vitamins were found to reduce the predisposition to develop tumours in animals and humans. In conclusion, in this review we describe the role of flavonoids and vitamins in cancer.

Expression of the iron-activated nspA and secY genes in Neisseria meningitidis group B by Fur-dependent and -independent mechanisms.

Our whole-genome microarray studies of Neisseria meningitidis MC58 previously identified a set of 153 genes whose transcription was activated during growth in iron. In this study, Fur-mediated regulation of the iron-activated nspA gene was confirmed, whereas iron-activated regulation of the secY gene was demonstrated to be Fur independent. Analysis of the Fur binding sequences in the nspA gene and an additional iron-activated and Fur-regulated gene identified a hexameric (G/T)ATAAT unit in the operator regions of these genes similar to that observed in Fur- and iron-repressed genes. These studies indicate that the expression of the iron-activated nspA and secY genes in N. meningitidis occur by Fur-dependent and -independent mechanisms, respectively.