S-Z Liu1, X Zhou1, A Song2, Z Huo3, Y-P Wang1, Y Liu1. 1. Department of Orthopaedic Surgery, Peking Union Medical College, Beijing, China. 2. Key Laboratory of Endocrinology, Department of Endocrinology, National Health and Family Planning Commission, Peking Union Medical College, Beijing, China. 3. Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, China.