SERPINE1 and esophageal squamous cell carcinoma: In addition, PAI-1 could promote the recruitment and polarization of macrophages in TME.32 The high infiltration of macrophages in pretreatment samples was found to be associated with a poor response to neoadjuvant chemotherapy.33 Therefore, the specific role of PAI-1 in the process of nCRT of ESCC requires further exploration.