Consequences of Nkiras deficiency for the EGF response

Cancer is a disease of aberrant intracellular signaling. The NF-κB family of transcription factors and the Ras family of small GTPases have emerged as particularly important mediators of the pro-proliferative signaling that drives tumorigenesis and carcinogenesis. The κB-Ras proteins, encoded by the genes Nkiras1 and Nkiras2, were previously shown to inhibit both NF-κB and Ras pathway activation through independent molecular mechanisms, implicating them as tumor suppressors with potentially broad relevance to human cancers. In mice, each κB-Ras protein can compensate fully for loss of the other, making the functionally redundant in the context of Ras signaling. To understand the global effects of full κB-Ras deficiency in the context of Ras activation, we use microarray analysis to compare the transcriptome of MEFs lacking only κB-Ras 1 (Nkiras1-/- Nkiras2+/+, 1SKO) and MEFs lacking both isoforms of κB-Ras (Nkiras1-/- Nkiras2-/-, DKO) with and without EGF stimulation. Mouse embyronic fibroblasts (MEFs) of the genotype Nkiras1-/- Nkiras2+/+ and Nkiras1-/- Nkiras2-/- were either left untreated or stimulated with 100 ng/ml EGF for 5 h. Total RNA was isolated and submitted to Arraystar for hybridization to a Nimblegen microarray.