Epidemiological studies show that the consumption of fruits and vegetables, rich in polyphenols, is linked to reduced cancer risk. Elderly men in France consuming the Mediterranean diet rich in vegetables, fruits, nuts, olive oil and also red wine, have a lot lower risk of developing prostate cancer than their counterparts in the US. Most studies about the anti-cancer effects of anthocyanins involved cyandin or malvidin. Feng and co-workers that cyanidin glycoside extracted from black raspberries killed leukemia cells in a dose-dependent manner but showed no cytotoxic effects in normal cells . A study with mice demonstrated cyanidin 3-glucoside and a bilberry extract significantly reduced the formation of intestinal adenoma  and study with human vulva cancer cells also confirmed the inhibitory action of cyanidin on overexpressing of the epidermal growth factor (EGF) receptor . Muñoz-Espada and Watkins investigated the protective effects of cyanidin and kaempferol in cultured prostate cancer cells and found that both phytochemicals reduced the production of cyclooxygenases-2 by mediating the actions of the nuclear factor kappaB and peroxisome proliferator-activated receptor gamma . Serafino and co-workers came to the conclusion that cyanidin 3-O-beta-glucopyranoside was candidate molecule for the treatment of melanoma . The demonstrated that cyanidin 3-O-beta-glucopyranoside reversed the melanoma cells from proliferating to the differentiated state. Treatment of the cancer cells with this anthocyanin decreased cell proliferation without inducing apoptosis.
A study by Faria and co-workers conducted at Faculty of Medicine of the University of Porto found that blueberry anthocyanins demonstrated anticancer properties by inhibiting cancer cell proliferation and invasion as well as acting chemoinhibitors . The scientists investigated the anticancer properties of an anthocyanin extract and an anthocyanin-pyruvic acid adduct extract on two breast cancer cell lines. They found that both extracts significantly reduced cell proliferation and showed significant anti-invasive potential in both cell lines.
 Cyanidin-3-rutinoside, a natural polyphenol antioxidant, selectively kills leukemic cells by induction of oxidative stress. J Biol Chem. 2007 May 4;282(18):13468-76.
 Effect of cyanidin-3-glucoside and an anthocyanin mixture from bilberry on adenoma development in the ApcMin mouse model of intestinal carcinogenesis--relationship with tissue anthocyanin levels. Int J Cancer. 2006 Nov 1;119(9):2213-20.
 Meiers S, Kemény M, Weyand U, Gastpar R, von Angerer E, Marko D. "The anthocyanidins cyanidin and delphinidin are potent inhibitors of the epidermal growth-factor receptor." J Agric Food Chem. 2001 Feb;49(2):958-62.
 Cyanidin attenuates PGE2 production and cyclooxygenase-2 expression in LNCaP human prostate cancer cells. J Nutr Biochem. 2006 Sep;17(9):589-96.
 Serafino A, Sinibaldi-Vallebona P, Lazzarino G, Tavazzi B, Rasi G, Pierimarchi P, Andreola F, Moroni G, Galvano G, Galvano F, Garaci E. " Differentiation of human melanoma cells induced by cyanidin-3-O-beta-glucopyranoside." FASEB J. 2004 Dec;18(15):1940-2.
 Blueberry anthocyanins and pyruvic acid adducts: anticancer properties in breast cancer cell lines. Phytother Res. 2010 Jun 17.