In order to accelerate BCC carcinogenesis in these studies, Ptchneo12/+ mice were crossed to K14-Cre-ER p53fl/fl mice and p53 was deleted in the Ptchneo12/+K14-Cre-ER p53fl/fl offspring at the age of 6 weeks by injection of 100 μg tamoxifen on 3 consecutive days. This evidence concerns the gene KRT14 and skin basal cell carcinoma.