Iliakis G, Okayasu R, Seaner R
Thomas Jefferson University, Department of Radiation Oncology and Nuclear Medicine, Philadelphia, PA 19107.
Int J Radiat Biol. 1988 Jul;54(1):55-62. doi: 10.1080/09553008814551501.
The purpose of this work was to investigate a possible correlation between DNA elution dose-response and cell radiosensitivity. For this purpose neutral (pH 9.6) DNA filter elution dose-response curves were measured with radiosensitive xrs-5 and the parental Chinese hamster ovary (CHO) cells in the logarithmic and plateau phase of growth. No difference was observed between the two cell types in the DNA elution dose-response curves either in logarithmic or plateau phase, despite the dramatic differences in cell radiosensitivity. This observation indicates that the shape of the DNA elution dose-response curve and the shape of the cell survival curve are not causally related. It is proposed that the shoulder observed in the DNA elution dose-response curve reflects either partial release of DNA from chromatin, or cell cycle-specific alterations in the physicochemical properties of the DNA.
本研究的目的是调查DNA洗脱剂量反应与细胞放射敏感性之间可能存在的相关性。为此，使用对辐射敏感的xrs-5细胞和处于对数生长期及平台期的亲代中国仓鼠卵巢（CHO）细胞，测量了中性（pH 9.6）DNA滤膜洗脱剂量反应曲线。尽管两种细胞类型的放射敏感性存在显著差异，但在对数期或平台期的DNA洗脱剂量反应曲线中，未观察到两者之间存在差异。这一观察结果表明，DNA洗脱剂量反应曲线的形状与细胞存活曲线的形状没有因果关系。有人提出，在DNA洗脱剂量反应曲线中观察到的肩部反映了DNA从染色质中的部分释放，或者是DNA物理化学性质的细胞周期特异性改变。
