Inositols as adjuvant treatments in oncology

Inositols are a complex family of biomolecules. The most phosphorylated form of myo-inositol (myo-Ins), inositol hexakisphosphate (InsP6), is of particular interest. This naturally occurring polyphosphorylated carbohydrate is abundantly present in many plant sources and in certain high-fiber foods, such as cereals and legumes. In addition to being found in plants, InsP6 is contained, although in much smaller amounts, in almost all mammalian cells where it is important in regulating vital cellular functions such as signal transduction, cell proliferation, and differentiation. For a long time, InsP6 has been recognized as a natural antioxidant. In the last several decades, inositols and InsP6 have received much attention for their unique and enigmatic role in cancer prevention, and control of tumor growth, progression, and metastasis. In this chapter, we show the efficacy of inositols and InsP6, discussing the molecular mechanisms under their anticancer action. A striking anticancer role of these molecules was demonstrated in different experimental models. Because they are abundantly present in regular diet, efficiently absorbed from the gastrointestinal tract, and safe, inositols and InsP6 hold great promise in our strategies for the prevention and therapy of cancer. Extensive laboratory and emerging clinical data accumulated so far strongly suggest their role either as an adjuvant or as an “alternative” to current chemotherapy for cancer.