TGFB1 and esophageal squamous cell carcinoma: To confirm whether TGF-β1 secreted by M2-TAMs directly influenced ESCC cisplatin resistance, ESCC cells were pretreated with recombinant human TGF-β1 (rhTGF-β1) protein. The CCK-8 results showed that the IC50 values of EC109 and E9706 cells that had been pretreated with rhTGF-β1 increased significantly (Fig. 2F).