Hisafumi Okabe
Hoffmann-La Roche
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Hisafumi Okabe.
Cancer Science | 2003
Kazuhiro Suganuma; Tetsuro Kubota; Yoshiro Saikawa; Sadanori Abe; Yoshihide Otani; Toshiharu Furukawa; Koichiro Kumai; Hirotoshi Hasegawa; Masahiko Watanabe; Masaki Kitajima; Hironobu Nakayama; Hisafumi Okabe
To identify chemoresistance‐related genes of gastric cancer, we utilized cDNA microarray technology. Thirty‐five gastric cancer specimens surgically resected at our institute between 1998 and 1999 were studied for quantification of expression of 6300 genes by means of oligonucleotide microarray methods, and the results were evaluated in comparison with the chemoresistance of the specimens, which was determined by MTT (tetrazolium‐based 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay. Inhibition rates (IR) were determined for cisplatin (DDP), 5‐fluorouracil (5‐FU), mitomycin C or doxorubicin. IR of 60% or more was regarded as sensitive to each agent, and IR of less than 40% was defined as resistant. Clustering was successfully completed for DDP, resulting in selection of 23 candidates as DDP‐resistance‐related genes, including vascular permeability factor, 2 membrane transporting subunits, and retinoblastoma‐binding protein‐1. In addition, further selection of DDP‐resistance‐related genes was performed according to these criteria: 1) Expression of the gene can be detected in more than 70% of resistant tumors. 2) Expression can be detected in less than 30% of sensitive tumors. 3) Expression in tumors is more than twice that of normal mucosa in more than 50% of specimens. Then, metallothionein‐IG and heparin‐binding epidermal growth factor‐like growth factor (HB‐EGF) were identified as candidate DDP‐resistance‐related genes. When known DDP‐resistance‐related genes were analyzed according to the MTT assay result, families of glutathione‐S‐transferase and cydooxygenase‐2 genes were also evaluated as resistance‐related genes. For 5‐FU resistance, dihydropyrimidine dehydrogenase and HB‐EGF‐like growth factor genes were also suggested to be resistance‐related genes. The present study demonstrated that oligonucleotide microarrays can provide information regarding chemoresistance factors in cancer. (Cancer Sci 2003; 94: 355–359)
Bioorganic & Medicinal Chemistry Letters | 2000
Kazunao Masubuchi; Mikio Taniguchi; Isao Umeda; Kazuo Hattori; Hitomi Suda; Yasunori Kohchi; Yoshiaki Isshiki; Toshiya Sakai; Masami Kohchi; Michio Shirai; Hisafumi Okabe; Masayuki Sudoh; Toshikazu Yamazaki; Nobuo Shimma
A novel Candida albicans chitin synthase 1 (CaChs1) inhibitor, RO-41-0986 (1) was discovered by random screening. Systematic modification led to the identification of a highly potent CaChs1 inhibitor, RO-09-3024 (2), having strong antifungal activity against Candida spp. in vitro.
Blood | 2004
Hidenori Sasaki; Ichiro Nishikata; Toshiyuki Shiraga; Ena Akamatsu; Takeshi Fukami; Tomonori Hidaka; Yoko Kubuki; Akihiko Okayama; Kenji Hamada; Hisafumi Okabe; Yoshinori Murakami; Hirohito Tsubouchi; Kazuhiro Morishita
Archive | 2002
Hideo Ishitsuka; Hisafumi Okabe; Nobuo Shimma; Takuo Tsukuda; Isao Umeda
Archive | 2001
Masaaki Oka; Yoshihiko Hamamoto; Hisafumi Okabe
Archive | 2003
Masaaki Oka; Yoshihiko Hamamoto; Norio Iizuka; Hisafumi Okabe; Kenji Hamada
Chimia | 2008
Ruth Duncan; Iwao Ojima; Dario Neri; Nobuo Shimma; Hisafumi Okabe; Hideo Ishitsuka; Hans Peter Märki
Archive | 2002
Hideo Ishitsuka; Hisafumi Okabe; Nobuo Shimma; Takuo Tsukuda; Isao Umeda
Archive | 2001
Yoshiko Ube-shi Hamamoto; Masaaki Oka; Hisafumi Okabe
Archive | 2001
Yoshiko Ube-shi Hamamoto; Masaaki Oka; Hisafumi Okabe