@article{oai:repo.qst.go.jp:00046185,
 author = {Kato, Takamitsu and Tsuda, Akihisa and Uesaka, Mitsuru and Fujimori, Akira and Kamada, Tadashi and Tsujii, Hirohiko and Okayasu, Ryuichi and 加藤 宝光 and 津田 晃久 and 上坂 充 and 藤森 亮 and 鎌田 正 and 辻井 博彦 and 岡安 隆一},
 journal = {Radiation Oncology (Online only URL:http://www.ro-journal.com/)},
 month = {Sep},
 note = {BACKGROUND: Chordoma, a rare cancer, is usually treated with surgery and/or radiation. However, very limited characterizations of chordoma cells are available due to a minimal availability (only two lines validated by now) and the extremely long doubling time. In order to overcome this situation, we successfully derived a cell line with a shorter doubling time from the first validated chordoma line U-CH1 and obtained invaluable cell biological data.
\nMETHOD: After isolating a subpopulation of U-CH1 cells with a short doubling time (U-CH1-N), cell growth, cell cycle distribution, DNA content, chromosome number, p53 status, and cell survival were examined after exposure to X-rays, heavy ions, camptothecin, mitomycin C, cisplatin and bleocin. These data were compared with those of HeLa (cervical cancer) and U87-MG (glioblastoma) cells.
\nRESULTS: The cell doubling times for HeLa, U87-MG and U-CH1-N were approximately 18 h, 24 h and 3 days respectively. Heavy ion irradiation resulted in more efficient cell killing than x-rays in all three cell lines. Relative biological effectiveness (RBE) at 10% survival for U-CH1-N was about 2.45 for 70keV/micro m carbon and 3.86 for 200keV/micro m iron ions. Of the four chemicals, bleocin showed the most marked cytotoxic effect on U-CH1-N.
\nCONCLUSION: Our data provide the first comprehensive cellular characterization using cells of chordoma origin and furnish the biological basis for successful clinical results of chordoma treatment by heavy ions.},
 title = {In vitro characterization of cells derived from chordoma cell line U-CH1 following treatment with X-rays, heavy ions and chemotherapeutic drugs},
 volume = {6},
 year = {2011}
}