Additionally, CXCL2 suppressed tumor growth and enhanced the efficacy of anti-PD-1 antibody therapy in ESCC mouse models.<h4>Conclusion</h4>Macrophage-specific CXCL2 represents a novel biomarker for predicting immunotherapy efficacy and may potentiate the efficacy of anti-PD-1 therapy in ESCC patients. Here, CXCL2 is linked to esophageal squamous cell carcinoma.