IL33 and esophageal squamous cell carcinoma: Furthermore, upon recognition of its receptor ST2, IL-33 attracts a significant number of Foxp3+Tregs to congregate in the stroma of ESCC, thereby initiating the IL-33/ST2/Foxp3+Treg/COX-2/PGs regulatory pathway, encouraging Foxp3+Treg secretion of cyclooxygenase-2 (COX-2) and enabling the conversion and production of prostaglandins (PGs).