1. Department of Dentistry and Oral Surgery, Unit of Sensory and Locomotor Medicine, Division of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui 910‑1193, Japan
2. Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812‑8582, Japan
3. Department of Tumor Pathology, Unit of Pathological Sciences, Division of Medicine, Faculty of Medical Sciences, University of Fukui, Fukui 910‑1193, Japan