1. Department of Natural Products Chemistry; School of Traditional Chinese Materia Medica; Shenyang Pharmaceutical University; Shenyang; China
2. The State Key Laboratory of Biotherapy and Cancer Center; West China Hospital; Sichuan University; Chengdu; China
3. Department of Pharmacology and The Penn State Cancer Institute; The Pennsylvania State University College of Medicine; Milton S. Hershey Medical Center; Hershey; Pennsylvania; USA