Division of Mathematical Oncology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.|Division of Molecular Cell Signaling, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.|Division of Molecular Cell Signaling, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.|Division of Cell Signaling and Molecular Medicine, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.|Division of Mathematical Oncology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.