1. Department of Gastroenterology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China
2. Department of Gastroenterology, First Affiliated Hospital, Zhengzhou University, Henan, Zhengzhou 450000, China
3. State Key Laboratory of Cancer Biology and Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China