New cancer cases are expected to surge 57% worldwide in the next two decades. The greatest burden will be in low- and middle-income countries that are ill equipped to face this epidemic. Similarly, in the United States, low-income populations are at greater risk for cancer. As most cancers contain over 50 genetic alterations, and as these alterations define dysregulation of over 10 different critical cellular signaling pathways, a "silver bullet" treatment is not effective against most cancers. Instead, the latest World Cancer Report (2012) suggests a research shift toward developing prevention strategies for cancer. Accumulating evidence suggests that a diet high in plant-based foods is preventive of a variety of chronic diseases, including cancer. A plethora of bioactive compounds-such as polyphenols, glucosinolates and carotenoids in fruits, vegetables, grains, and legumes-are shown to suppress a variety of biological capabilities required for tumor growth. While much research has shown that plant bioactive compounds can suppress sustained proliferative signaling, angiogenesis, and metastasis, as well as promote cancer stem cell apoptosis, public health campaigns to increase fruit and vegetable consumption have, overall, been less effective than desired. Thus, there is a need for innovative strategies to support increased consumption of bioactive compounds for cancer prevention particularly in vulnerable populations. Many practices of the farm-to-fork continuum, including preharvest practices, postharvest storage, and processing and consumer practices, affect a food's bioactive compound content, composition, and chemopreventive bioactivity. Food system practices may be adjusted to reduce the toxic compound levels (e.g., glycoalkaloids in potatoes) and improve the bioactive compound profile, thus, elevate the cancer fighting properties of fruits, vegetables, and other food products. This review presents current scientific evidence outlining farm-to-fork effects on fruit and vegetable bioactive compounds in order to aid the development of new and reasonable strategies for cancer prevention.
Keywords: Food systems; cancer prevention; cancer stem cells; carotenoids; flavonoids; glucosinolates; polyphenols; processing.