Mollugin inhibits proliferation and induces apoptosis by suppressing fatty acid synthase in HER2-overexpressing cancer cells through modulation of a HER2/Akt/SREBP-1c signaling
Menée sur des lignées cellulaires humaines de cancer du sein et de cancer de l'ovaire, cette étude montre qu'une naphto-hydroquinone présente dans les racines de la Rubia cordifolia, en supprimant l'activité de l'acide gras synthase via un mécanisme impliquant la voie de signalisation HER2/Akt/SREBP-1c, induit l'apoptose des cellules tumorales surexprimant le récepteur HER2 et inhibe leur prolifération
Mollugin is a naphthohydroquine found in the roots of Rubia cordifolia, and has been reported to have a variety of biological activities, including anti-inflammatory and apoptotic effects. In the present study, we investigated the molecular mechanisms by which mollugin exerts anti-tumor effect in HER2-overexpressing cancer cells. Our results showed that mollugin exhibited potent inhibitory effects on cancer cell proliferation, especially in HER2-overexpressing SK-BR-3 human breast cancer cells and SK-OV-3 human ovarian cancer cell lines in a dose- and time-dependent manner without affecting immortalized normal mammary epithelial cell line MCF-10A. Furthermore, we found that a blockade of Akt/SREBP-1c signaling through mollugin treatment significantly reduced FAS expression and subsequently suppressed cell proliferation and induced apoptosis in HER2-overexpressing cancer cells. Mollugin treatment caused a dose-dependent inhibition of HER2 gene expression at the transcriptional level, potentially in part through suppression of NF-kappaB activation. The combination of mollugin with a MEK1/2 inhibitor may be required in order to achieve optimal efficacy in HER2-overexpressing cancers. These data provide evidence that mollugin inhibits proliferation and induces apoptosis in HER2-overexpressing cancer cells by blocking expression of the FAS gene through modulation of a HER2/Akt/SREBP-1c signaling pathway. Our findings suggest that mollugin is a novel modulator of the HER2 pathway in HER2-overexpressing cancer cells with a potential role in the treatment and prevention of human breast and ovarian cancer with HER2 overexpression. J. Cell. Physiol. (c) 2012 Wiley Periodicals, Inc.
http://onlinelibrary.wiley.com/doi/10.1002/jcp.24258/abstract