1. Cancer Research Institute, Central South University, Changsha, Hunan, People's Republic of China; Disease Genome Research Center, Central South University, Changsha, Hunan, People's Republic of China; Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education; Key Laboratory of Carcinogenesis, Ministry of Health.
2. Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China.