SERPINE1 and neoplasm: Several reports showed that CAFs promote tumour progression and resistance to chemotherapy by secreting various growth factors and inflammatory chemokines.4, 5 In this study, the level of PAI‐1 and TGF‐β secreted after suppression of the MF characteristics of CAFs by PAI‐1 inhibition was significantly lower than that from CAFs without PAI‐1 inhibition.