While tumours readily develop in mice following DMBA/TPA treatment, conditional deletion of floxed Grhl3 in the differentiated cell-rich suprabasal epidermis using a tamoxifen-inducible Cre recombinase, driven by the IVL promoter (IVL–Cre–ERT2), confers an increased susceptibility to tumour formation similar to that seen with K14Cre Grhl3 cKO mice. Here, MAPK3 is linked to neoplasm.