1. Department of Medical Oncology, The First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
2. Department of Gastroenterology, The Central Hospital of Ankang City, Ankang, Shaanxi 725000, P.R. China
3. Department of Pathology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, P.R. China
4. Department of Oncology, Shangluo Central Hospital, Shangluo, Shaanxi, 726000, P.R. China
5. Center for Translational Medicine, The First Affiliated Hospital of Xian Jiaotong University, Xi'an, Shaanxi 710061, P.R. China