1. Department of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, 1-37-1 Kami-Ikebukuro, Toshima, Tokyo 170-8455, Japan, CREST, JST, Toshima, Tokyo 170-8455, Japan, and Department of Molecular Cell Biology, Institute of DNA Medicine, The Jikei University School of Medicine, Minato, Tokyo, Japan