Inositol phosphates have novel anticancer function.
Inositol hexaphosphate (InsP6, phytic acid) is ubiquitous in the plant kingdom and is abundant in cereals and legumes. In much smaller amounts InsP6 and its lower phosphorylated forms (InsP1-5) are contained in most mammalian cells, where they are important in regulating vital cellular functions. Both in vivo and in vitro experiments have suggested striking anticancer potential (preventive as well as therapeutic) for InsP6 with and without inositol. In addition to reduce cell proliferation, InsP6 increases differentiation of malignant cells often resulting in reversion to the normal phenotype. InsP6 is quickly absorbed from the rat stomach and upper intestine and distributed as inositol and InsP1. In vitro it is instantaneously taken up by malignant cells undergoing variable dephosphorylation to inositol and InsP1-5, pointing toward their role in mediating the action of InsP6. Because InsP6 is high in high-fiber diets, our studies also may explain, at least in part, the epidemiologic observation showing high-fiber diets are associated with a lower incidence of certain cancers. Although further studies are needed to elucidate the mechanism(s) of this action, inclusion of InsP6 in our strategies for cancer prevention and therapy is warranted.
Shamsuddin
A M
AM
Department of Pathology, University of Maryland School of Medicine, Baltimore 21201-1192.
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000592:standards / Q000627:therapeutic use*; D002455:Cell Division / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D004043:Dietary Fiber / Q000592:standards / Q000627:therapeutic use; D006801:Humans; D007295:Inositol Phosphates / Q000494:pharmacology / Q000592:standards / Q000627:therapeutic use*; D051379:Mice; D009369:Neoplasms / Q000178:diet therapy / Q000473:pathology / Q000517:prevention & control*; D009374:Neoplasms, Experimental / Q000178:diet therapy / Q000473:pathology / Q000517:prevention & control*; D010833:Phytic Acid / Q000494:pharmacology / Q000592:standards / Q000627:therapeutic use; D051381:Rats; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D004043:Dietary Fiber; D007295:Inositol Phosphates; D010833:Phytic Acid