School of Life Sciences;
Zhengzhou University;
Zhengzhou 450001;
China;
Thoracic Surgery Department;
National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital;
Chinese Academy of Medical Sciences and Peking Union Medical College;
Beijing 100021;
China;
School of Pharmaceutical Sciences(Shenzhen);
Sun Yat-sen University;
Shenzhen 518107;
China;
Tryptophan 2; 3-dioxygenase 2; M2 macrophage; Esophageal squamous cell carcinoma; IL-8; KYN;