1. College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
2. Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
3. Department of Biological Sciences, Lehman College, The City University of New York, Bronx, NY 10468, USA
4. Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong