PPARD and skin neoplasm: 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