NOX4 and neoplasm: In light of the immunosuppressive effects employed by CAFs in resistance to PD-1/PD-L1 immunotherapy, therapeutic interventions targeting key molecules within the underlying mechanism such as TGF-β, NOX4 and exosome, are being explored in clinical trials to augment tumor immune efficacy against PD-1/PD-L1 (Pan et al., 2020; Kato et al., 2021; Li et al., 2023).