Comparative analysis of G2 arrest after irradiation with 75 keV carbon-ion beams and 137Cs gamma-rays in a human lymphoblastoid cell line.
Heavy-ion beams are more effective than gamma-rays in causing G2 arrest. In this study, we investigated the expression of Wee1 and Cdc2 protein levels in order to analyze the G2 arrest caused by carbon-ion beam irradiation. Human lymphoblastoid TK6 cells were exposed to a 75 keV carbon-ion beam or 137Cs gamma-rays. Although the levels of Wee1 and Cdc2 protein were increased after exposure to either beam, Wee1 protein levels were influenced more by carbon-ion beam irradiation than by gamma-rays. To the contrary, Cdc2 protein levels were increased more by gamma-rays than by carbon-ion beams. These findings suggest that the G2 arrest produced by heavy-ion beams, such as the carbon-ion irradiation used in this study, might be associated with the overexpression of the Wee1 protein and of Cdc2 phosphorylation regulated by Wee1. Together, these events may act to prolong the length of G2 arrest.
Matsumura
Satoko
S
Division of Multidisciplinary Radiotherapy, Biomedical Research Center, Osaka University Graduate School of Medicine (D10), 2-2 Yamadaoka, Suita, Osaka 5650871, Japan. matumura@radonc.med.osaka-u.ac.jp
Matsumura
Tatsushi
T
Ozeki
Shuji
S
Fukushima
Shoko
S
Yamazaki
Hideya
H
Inoue
Takehiro
T
Inoue
Toshihiko
T
Furusawa
Yoshiya
Y
Eguchi-Kasai
Kiyomi
K
D016203:CDC2 Protein Kinase / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism; D019926:Cyclin B / Q000378:metabolism; D056744:Cyclin B1; D004307:Dose-Response Relationship, Radiation; D016195:G2 Phase / Q000528:radiation effects*; D005720:Gamma Rays; D020450:Heavy Ions; D006801:Humans; D066298:In Vitro Techniques; D009687:Nuclear Proteins; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D012062:Relative Biological Effectiveness; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000528:radiation effects; D020687:cdc25 Phosphatases / Q000378:metabolism
C534699:CCNB1 protein, human; D018797:Cell Cycle Proteins; D019926:Cyclin B; D056744:Cyclin B1; D009687:Nuclear Proteins; D016159:Tumor Suppressor Protein p53; D011505:Protein-Tyrosine Kinases; C499349:WEE1 protein, human; D016203:CDC2 Protein Kinase; C517008:CDC25B protein, human; C517009:CDC25C protein, human; D020687:cdc25 Phosphatases