Suppression of oncoprotein Her-2 and DNA damage after treatment with Flavan-3- ol vitis labrusca extract.

Hepatocellular carcinoma and breast cancer are the most prevalent cancers in the world with high morbidity and mortality. Although there are effective drugs for treating advanced stages of liver and breast cancers, the prognosis for patients with liver cancer remains poor, and patients with breast cancer show considerable mortality. Therefore, it is crucial to explore new therapeutic agents for the inhibition of carcinogenesis. This study examined the anti-carcinogenic effect of Vitis labrusca seed extract (VLE), which is a component of winery waste, on liver (HepG2) and breast cancers (MCF-7) cells. The results found in this study demonstrated VLEinduced DNA damage in liver and breast cancer cells. VLE treatment in both cell lines was accompanied by high NO production and upregulation of p53. A significant decrease in total PARP expression was also found in HepG2 cells. In the MCF-7 cell line, VLE treatment increased the expression of Bax and AIF, and decreased total PARP expression. Surprisingly, VLE suppressed Her-2 expression in HepG2 cells and caused a subtle, but significant downregulation of Her-2 in MCF-7 cells. The possible anti-carcinogenic effect of VLE reported in this study suggests the potential of this extract to be used for the development of novel therapeutic agents for the treatment of different kinds of cancers.