In sharp contrast, activation of the reduced levels of MycERT2 from only a single Rosa26 promoter (equivalent to levels of endogenous Myc in hypomorphed MR animals) in the indolent tumours of hemizygous KR26MT2/+ (lung) and KCR26MT2/+ (pancreas) mice elicited no discernible change in lung adenoma/PanIN morphology, proliferation or stroma (Fig. 3a, b). This evidence concerns the gene MYC and lung adenoma.