APEX1 and neoplasm: Relative to HCC827R‐CSC‐EVs shNC, HCC827R‐CSC‐EVs shAPE1 resulted in down‐regulated levels of APE1, IL‐6 and p‐STAT3/STAT3 in tumour tissues of Erlotinib‐treated mice (all p < .01) (Figure 6C,D).