1. Hunan Province Key Laboratory of Tumor Cellular and Molecular Pathology, Cancer Research Institute, School of Medicine, University of South China, Hengyang, P.R. China
2. Department of Radiotherapy, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
3. Department of Respiratory, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, P.R. China