NOX4 and neoplasm: However, while the role of NOX4 in favouring TGF-β-induced fibroblast transdifferentiation has been undisputed over the years in different pathologies, including several cancers,15,42–44 a very recent study indicated that NOX4 is dispensable for skin myofibroblast differentiation and wound healing.16 In that report, NOX4-/- mice did not display differences compared to WT mice in terms of wound healing, similar to the lack of impact of NOX4 invalidation on iCCA tumours in the SB1 syngeneic model found in our study.