1. School of Life Sciences, Tianjin University, Weijin Road 92, Tianjin 300072, China
2. School of Medicine, Nankai University, Tianjin, P.R. China
3. Cancer Hospital of Tianjin Medical University, Tianjin, P.R. China
4. State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, 300350, China