Format

Send to

Choose Destination
Biochem Biophys Res Commun. 2011 Oct 28;414(3):551-6. doi: 10.1016/j.bbrc.2011.09.115. Epub 2011 Oct 1.

Green tea polyphenol epigallocatechin-3-gallate suppresses melanoma growth by inhibiting inflammasome and IL-1β secretion.

Author information

1
Department of Dermatology, University of Colorado School of Medicine, Aurora, CO 80045, USA.

Abstract

Epigallocatechin-3-gallate (EGCG), the major polyphenolic component of green tea, has been demonstrated to possess anti-inflammatory, antioxidant, anti-mutagenic and anti-carcinogenic properties. The anti-melanoma effect of EGCG has been previously suggested, but no clear mechanism of action has been established. In this study, we demonstrated that EGCG inhibits melanoma cell growth at physiological doses (0.1-1 μM). In the search for mechanisms of EGCG-mediated melanoma cell suppression, we found that NF-κB was inhibited, and that reduced NF-κB activity was associated with decreased IL-1β secretion from melanoma cells. Since inflammasomes are involved in IL-1β secretion, we investigated whether IL-1β suppression was mediated by inflammasomes, and found that EGCG treatment led to downregulation of the inflammasome component, NLRP1, and reduced caspase-1 activation. Furthermore, silencing the expression of NLRP1 abolished EGCG-induced inhibition of tumor cell proliferation both in vitro and in vivo, suggesting a key role of inflammasomes in EGCG efficacy. This paper provides a novel mechanism for EGCG-induced melanoma inhibition: inflammasome downregulation→decreased IL-1β secretion→decreased NF-κB activities→decreased cell growth. In addition, it suggests inflammasomes and IL-1β could be potential targets for future melanoma therapeutics.

PMID:
21982776
PMCID:
PMC3430966
DOI:
10.1016/j.bbrc.2011.09.115
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center