However, a recent study by Kaufman et al. using an LKB1 loss-associated gene expression signature suggested that human lung cancer differs substantially from the expression profile of the krasG12D/lkb1 floxed GEM model [33], therefore raising the concern that the sensitivity to MEK inhibition observed in GEM models may not be extrapolated to human lung cancer with LKB1 mutation. This evidence concerns the gene MAP2K7 and lung cancer.