Corresponding authors: Qinjun Wei, Ph.D., Department of Biotechnology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu 210029, China, Tel(Fax): +86-25-86862837. E-mail: wqj@ njmu.edu.cn; Gnangqian Xing, M.D., Department of Otolaryngology, the First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu 210029,China. Tel: +86-25- 83718836. E-mail: xing-gq@ 163.com.