1. The Third School of Clinical Medicine, Southern Medical University, Guangzhou, Guangdong 510500, P.R. China
2. Department of Obstetrics and Gynecology, Fengxian Hospital, Southern Medical University, Shanghai 201499, P.R. China
3. State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200240, P.R. China
4. Department of Obstetrics and Gynecology, The Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, Changzhou, Jiangsu 213000, P.R. China