Foodstuffs for preventing cancer: the preclinical and clinical development of berries

Abstract

Laboratory research involving berries is a promising example of food-based cancer prevention. Berries contain many known chemopreventive agents such as anthocyanins and ellagitannins that can be greatly concentrated in freeze-dried berry powders. Based on our program of berry research, this commentary presents the first reported stepwise scheme for the preclinical and clinical development of foodstuffs for cancer prevention. Our preclinical work within this scheme includes promising approaches for assessing the chemopreventive potential of berry powder and berry extracts in preclinical model systems, for determining the mechanisms of action of these agents, and for identifying the active constituents in berries. The commentary also presents preliminary results of clinical trials in the oral cavity, esophagus, and colon using various formulations of freeze-dried berries. The relative merits of berry powders, extracts, or individual constituents (anthocyanins) for cancer prevention are also discussed.

Figures

Fig. 1

Scheme for assessing berries (or other foodstuffs) for chemopreventive efficacy.

Fig. 2

Effects of black raspberries on cellular events and associated genes in the N-nitrosomethylbenzylamine (NMBA)-treated rat esophagus. PCNA, proliferating cell nuclear antigen; COX-2, cyclooxygenase-2; PGE2, prostaglandin E2; TUNEL, terminal deoxynucleotidyl transferase dUTP nick end labeling; iNOS, inducible nitric oxide synthase; NF-κB, nuclear factor kappa B; VEGF-1, vascular endothelial growth factor-1; HIF-1α, hypoxia-inducible factor-1α.