Xiao Dan1, Shi Yuankai2, Wang Chen3. 1. Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China; Beijing Institute of Respiratory Medicine, Beijing, China. Electronic address: danxiao@263.net. 2. Department of Medical Oncology, Cancer Institute Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, National Center for Anti-cancer Drugs Clinical Study, Beijing Key Laboratory of Clinical Study on Anticancer Molecular Targeted Drugs, Beijing, China. 3. Beijing Institute of Respiratory Medicine, Beijing, China; National Clinical Research Centre for repiratory disease, Beijing Hospital, Beijing, China.