1. Department of Breast Oncology, National Hospital Organization Kyushu Cancer Center, Fukuoka 811‑1395, Japan
2. Department of Cellular and Molecular Biology, Hiroshima University Institute of Biomedical and Health Sciences, Hiroshima 734‑8553, Japan
3. Department of Breast Surgery, Japan Agricultural Co‑operatives Hiroshima General Hospital, Hatsukaichi, Hiroshima 738‑8503, Japan
4. Section of Pathological Research and Laboratory, Japan Agricultural Co‑operatives Hiroshima General Hospital, Hiroshima 738‑8503, Japan
5. Department of Surgery, Nishiki Hospital, Yamaguchi 741‑0061, Japan