The histopathological features of K14:BRAFV600E-SOX2fl/fl and Ivl:BRAFV600E-SOX2fl/fl tumours were similar to those expressing the wild-type Sox2 allele, including an enlarged epidermis displaying vertical columns of keratinocytes, incomplete maturation of keratinocytes, increased proliferation and MYC and pSTAT3 activation (Supplementary Fig. 9a). Here, KRT14 is linked to neoplasm.