present study exhibit that ecotopically muting IR-induced NFkB with DIkBa robustly induced cell death in HNSCC cells demonstrating that IR-induced NFkB regulates cell death at least in this setting. Furthermore, to causally delineate that EKB-569 dependent silencing of NFkB mediates the induced radiosensiti- zation, we analyzed their effect on NFkB overexpressed cells. For the first time, the results of the present study imply that EKB-569 inhibits HNSCC cell survival and viability by selectively targeting NFkB. In summary, these results demonstrate that EKB-569 signifi- cantly inhibits IR-induced NFkB activity in human HNSCC cells. Furthermore, this study identifies the EKB-569-associated inhibi- tion of NFkB pathway survival signaling blue print, more precisely to the regimen of the treatment modality, in this case IR. Evidently, treatment with EKB-569 profoundly conferred IR- inhibited HNSCC cell survival and viability. 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PLoS ONE | www.plosone.org 11 December 2011 | Volume 6 | Issue 12 | e29705