As 50% of human NSCLC carry mutations in genes that encode activators of the mitogenic cascade (RAS-RAF-MEK-ERK) [12] and this cascade is known to induce a target gene of ß-catenin, c-MYC [13], we decided to directly examine the ability of c-MYC to promote tumor progression in our RAF-driven murine lung cancer model. This evidence concerns the gene RAF1 and non-small cell lung carcinoma.