APEX1 and esophageal squamous cell carcinoma: Collectively, we propose the following scientific hypothesis: In ESCC patients undergoing radical resection with adjuvant chemotherapy, elevated APE1 expression (1) promotes increased tumor infiltration depth and advanced T-stage, and (2) induces significant enrichment of CAFs and Tregs, fostering an immunosuppressive tumor microenvironment that ultimately contributes to poor chemotherapeutic outcomes.