Mulberry anthocyanins, cyanidin 3-rutinoside and cyanidin 3-glucoside, exhibited an inhibitory effect on the migration and invasion of a human lung cancer cell line.

Anthocyanins, present in various fruits and vegetables as natural colorant, have been well characterized to be involved in various bioactive properties and are wildly used for their antioxidant properties. Furthermore, recent studies have revealed pleiotropic anticancer and antiproliferative capabilities of anthocyanin. Berry extract contains high amounts of anthocyanins and is commonly used in diet or in some therapeutic applications. In this study, we first observed that cyanidin 3-rutinoside and cyanidin 3-glucoside (extracted from Morus alba L.) exerted a dose-dependent inhibitory effect on the migration and invasion, of highly metastatic A549 human lung carcinoma cells in absence of cytotoxicity. The results showed that cyanidin 3-glucoside and cyanidin 3-rutinoside treatments could decrease the expressions of matrix matalloprotinase-2 (MMP-2) and urokinase-plasminogen activator (u-PA) in a dose-dependent manner and enhance the expression of tissue inhibitor of matrix matalloprotinase-2 (TIMP-2) and plasminogen activator inhibitor (PAI). Further analysis with semi-quantitative RT-PCR showed that these alterations were all on the transcriptional level. Further, a treatment of cyanidin 3-rutinoside and cyanidin 3-glucoside also resulted in an inhibition on the activation of c-Jun and NF-kappaB. Together, these result suggested that anthocyanins could decrease the in vitro invasiveness of cancer cells and therefore, may be of great value in developing a potential cancer therapy.