Apoptosis induced by high-LET radiations is not affected by cellular p53 gene status
Apoptosis induced by high-LET radiations is not affected by cellular p53 gene status
复制标题
DOI：
10.1080/09553000500280484
复制
发表时间：
2005-08-01
影响因子：
2.6
通讯作者：
Ohnishi, T
中科院分区：
文献类型：
--
作者：
Takahashi, A;Matsumoto, H;Ohnishi, T
为了进一步了解高线性能量传递（LET）辐射的生物学效应，我们研究了野生型、突变型和p53基因缺失型细胞在高线性能量传递（LET）辐射下的辐射诱导凋亡。使用了三种人类肺癌细胞系。除了p53基因外，这些细胞系具有相同的基因型。细胞暴露于x射线或高let辐射（13-200 keV μ m(-1)）使用不同的核离子束。细胞辐射敏感性用集落形成测定法测定。荧光显微镜下Hoechst 33342染色检测细胞凋亡并定量。结果发现：(1)细胞对高let辐射的敏感性（485 keV μ m(-1)）无显著差异，尽管野生型p53细胞对x射线的敏感性高于突变型p53或p53-null细胞；(2)与突变型p53和p53-null细胞相比，野生型p53细胞x射线诱导的凋亡频率更高；(3) 200 keV μ m（-1）的Fe束以p53不依赖的方式诱导细胞凋亡。结果表明，高let辐射诱导人肺癌细胞凋亡的方式似乎不依赖于细胞的p53基因状态。
To learn more about the biological effects of high-linear energy transfer (LET) radiations, we examined radiation-induced apoptosis in response to high-LET radiations in cells with wild-type, mutated and null p53 gene. Three human lung cancer cell lines were used. These lines had identical genotypes, except for the p53 gene. Cells were exposed to X-rays or high-LET radiations (13-200 keV mu m(-1)) using different nuclei ion beams. Cellular radiation sensitivities were determined with the use of colony-forming assays. Apoptosis was detected and quantified using Hoechst 33342 staining with fluorescence microscopy. It was found that (1) there was no significant difference in cellular sensitivity to high-LET radiation (485 keV mu m(-1)), although the sensitivity of wild-type p53 cells to X-rays was higher than that of mutated p53 or p53-null cells; (2) X-ray-induced apoptosis at higher frequencies in wild-type p53 cells when compared with mutated p53 and p53-null cells; and (3) Fe beams (200 keV mu m(-1)) induced apoptosis in a p53-independent manner. The results indicate that high-LET radiations induces apoptosis in human lung cancer cells in a manner that does not seem to depend on the p53 gene status of the cells.