1. Department of Otolaryngology/Head and Neck Surgery, Hamamatsu University School of Medicine, Shizuoka, Japan
2. Department of Otolaryngology/Head and Neck Surgery, Jichi Medical University, Tochigi, Japan
3. Department of Otolaryngology/Head and Neck Surgery, Laboratory of Head and Neck Cancer Biology, University of Michigan, Ann Arbor, MI, USA