Strawberries contain a wide array of components that have been studied for their chemopreventive potential, including vitamins C and E, dietary fiber and phytochemicals such as ellagic acid, shown in laboratory studies to exhibit the ability to prevent cancers of the skin, bladder, lung, esophagus and breast.
Researchers from The Ohio State University investigated the effects of strawberries on tumor formation in an animal model of oral cancer developed to mimic conditions found in human oral mucosa after exposure to carcinogens such as tobacco and alcoholic beverages. Hamsters were given 5% or 10% lyophilized strawberries (LS) in their diet prior to, during and following or only following 12 weeks of carcinogen treatment. After 12 weeks of treatment, there were significantly fewer tumors found in the LS-treated groups as compared with the carcinogen controls, and histological examination revealed a significant reduction in the number of early lesions. The fact that little or no reduction in the size of large tumors was seen suggests that the maximum effect of LS was on early-developing tumors. Also, adding LS following 12 weeks of carcinogen treatment did not result in the reduction of any pre-existing dysplastic lesions, suggesting that the progression to malignancy of both pre-existing and newly-arising dysplasia was inhibited by LS. Researchers also noted a modification in gene expression related to the development of oral cancer.
These data show for the first time that incorporating strawberries (as LS) in the diet is effective in inhibiting the development of oral cancer in an experimental model.
Casto BC, Knobloch TH, Galioto RL, Yu Z, Accurso BT, Warner BM. Chemoprevention of oral cancer by lyophilized strawberries. Anticancer Res. 2013;33(11): 4757-4766. http://ar.iiarjournals.org/content/33/11/4757.abstract?sid=351203f5-4c50-41f0-967d-c0f3b5a7f8e9