Relationship of HepG2 cell sensitivity to continuous low dose-rate irradiation with ataxia-telangiectasia mutated phosphorylation / 南方医科大学学报
Journal of Southern Medical University
;
(12): 1391-1395, 2007.
Article
Dans Chinois
| WPRIM
| ID: wpr-283122
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the changes of ataxia-telangiectasia mutated (ATM) phosphorylation in HepG(2) cells in relation to HepG(2) cell survival under continuous low dose-rate irradiation.</p><p><b>METHODS</b>HepG(2) cells were exposed to equivalent irradiation doses delivered at either a continuous low dose-rate (7.76 cGy/h) or a high dose-rate (4500 cGy/h), and the phosphorylated ATM proteins and surviving fraction of HepG(2) cells after the exposures were compared.</p><p><b>RESULTS</b>The phosphorylation of ATM protein was maximal at 0.5 Gy irradiation delivered at either a high doserate or a continuous low doserate. As the radiation dose increased, ATM protein phosphorylation decreased under continuous low dose-rate irradiation, but remained stable under high dose-rate irradiation. With comparable ATM protein phosphorylation induced by continuous low dose-rate irradiation and high dose-rate irradiation, there was no significant difference in the surviving fraction of HepG(2) cells (P>0.05), but at a significantly lower ATM protein phosphorylation level than that induced by high dose-rate irradiation, continuous low dose-rate irradiation resulted in increased cell killing (P<0.01).</p><p><b>CONCLUSION</b>Continuous low dose-rate irradiation increases HepG(2) cells radiosensitivity as compared with high dose-rate irradiation. Increased cell killing following continuous low dose-rate irradiation is associated with reduced phosphorylated ATM protein, and inhibition of ATM phosphorylation may increase the radiosensitivity of HepG(2) cells.</p>
Texte intégral:
Disponible
Indice:
WPRIM (Pacifique occidental)
Sujet Principal:
Phosphorylation
/
Effets des rayonnements
/
Radiotolérance
/
Facteurs temps
/
Survie cellulaire
/
Protein-Serine-Threonine Kinases
/
Protéines du cycle cellulaire
/
Protéines suppresseurs de tumeurs
/
Lignée cellulaire tumorale
/
Protéines de liaison à l'ADN
Type d'étude:
Etude diagnostique
Limites du sujet:
Animaux
/
Humains
langue:
Chinois
Texte intégral:
Journal of Southern Medical University
Année:
2007
Type:
Article
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