The chemopreventive power of isothiocyanates

Isothiocyanates are derived from their naturally-occurring glucosinolate precursors, which are abundant in cruciferous vegetables. Numerous scientific studies beginning more than half a century ago have documented the chemoprotective activities of these compounds. Isothiocyanates have numerous protein targets through which they exert protection in the context of various diseases such as cancer, neurodegeneration, inflammatory disease, metabolic disease and infection. The major mechanisms by which the isothiocyanates confer protection involve induction of stress response pathways that restore the cellular redox and protein homeostasis, and contribute to resolution of inflammation. However, high concentrations of isothiocyanates cause cell cycle arrest and selectively kill cancer cells by inducing apoptosis, autophagy or necrosis. In this review, we present readers with a detailed overview of isothiocyanates functions and discuss their molecular targets and antineoplastic effects. Furthermore, we provide an up-to-date summary of the evidence on the chemoprotective activities of the most widely-studied isothiocyanates: sulforaphane, phenethyl isothiocyanate (PEITC) and benzyl isothiocyanate (BITC).