Expression of Ku80 correlates with sensitivities to radiation in cancer cell lines of the head and neck.
The Ku protein is essential for the repair of a majority of DNA double-strand breaks in mammalian cells. The purpose of this study was to investigate the relationship between the expression of Ku70/80 and sensitivity to radiation in cancer cell lines of the head and neck. The sensitivity to radiation in various head and neck cancer cell lines (AMC-HN-1 to -9) was analyzed by colony forming assay. Of the nine cell lines examined, the most radiosensitive cell line (AMC-HN-3) and the most radioresistant cell line (AMC-HN-9) were selected for this experiments. The expression of Ku70/80 was examined after irradiation using real time PCR, Western blotting and immunofluorescence in two different cell lines. Cell cycle distribution after irradiation were analysed. A differential radioresponse was demonstrated by expression of Ku70/80 in AMC-HN-3 and AMC-HN-9 cells. While the expression of Ku70 was slightly increased in the radioresistant AMC-HN-9 cell line, the expression of Ku80 was remarkably increased, suggesting a correlation between Ku80 expression and radiation resistance. Overexpression of Ku80 plays an important role in the repair of DNA damage induced by radiation. Ku80 expression may provide an effective predictive assay of radiosensitivity in head and neck cancers.
Chang
Hyo Won
HW
Department of Otolaryngology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Republic of Korea.
Kim
Sang Yoon
SY
Yi
So-Lyoung
SL
Son
Se-Hee
SH
Song
Do Young
DY
Moon
Su Young
SY
Kim
Jong Hoon
JH
Choi
Eun Kyung
EK
Ahn
Seung Do
SD
Shin
Seong Soo
SS
Lee
Kang Kyoo
KK
Lee
Sang-Wook
SW
D034961:Antigens, Nuclear / Q000378:metabolism*; D017209:Apoptosis / Q000528:radiation effects; D015153:Blotting, Western; D002470:Cell Survival / Q000528:radiation effects; D004249:DNA Damage; D004260:DNA Repair; D004273:DNA, Neoplasm / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D006258:Head and Neck Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D000072200:Ku Autoantigen; D009363:Neoplasm Proteins / Q000378:metabolism*; D014411:Neoplastic Stem Cells / Q000473:pathology / Q000528:radiation effects; D011836:Radiation Tolerance; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D014407:Tumor Cells, Cultured
D034961:Antigens, Nuclear; D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; C000606509:Xrcc6 protein, human; D000072200:Ku Autoantigen