1. Experimental Pathology and Chemotherapy Division, National Cancer Center Research Institute, Tokyo,
2. Department of Urology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba,
3. Department of Urology, Hitachi Inc. Mito General Hospital, Ibaraki,
4. Electron Microscopy Laboratory, National Cancer Center Hospital and
5. Chromosome Research Center, Olympus Optical Co. Ltd, Tokyo, Japan