In skin tumour mouse model, Tan et al. showed, PPARβ/δ‐knockout fibroblasts remarkably increased the H2O2 production in the adjacent epidermis, subsequently triggering an RAF/MEK‐mediated NRF2 activation that elicits a strong antioxidant and cytoprotective response, which resulted in fewer and smaller skin tumours when comparing to wild‐type mice exposed to topical carcinogens.68 This evidence concerns the gene MAP2K7 and skin neoplasm.