Southern Medical University - Department of Gastroenterology, Southern Medical University - Department of Gastroenterology, Southern Medical University - Department of Gastroenterology, National University of Singapore, Cancer Science Institute of Singapore, Guangdong Second Provincial General Hospital, Department of Gastroenterology, Southern Medical University - Department of Gastroenterology, Southern Medical University - Department of Gastroenterology, Memorial University of Newfoundland, Faculty of Medicine, National University of Singapore, Department of Physiology and Southern Medical University - Guangdong Provincial Key Laboratory of Gastroenterology