Bortezomib reduces the tumorigenicity of multiple myeloma via downregulation of upregulated targets in clonogenic side population cells. oleh Miho Nara, Kazuaki Teshima, Atsushi Watanabe, Mitsugu Ito, Keiko Iwamoto, Atsushi Kitabayashi, Masaaki Kume, Yoshiaki Hatano, Naoto Takahashi, Shinsuke Iida, Kenichi Sawada, Hiroyuki Tagawa