Yang C H, Craise L M
NASA Johnson Space Center, Houston, TX 77058, USA.
Adv Space Res. 1994;14(10):115-20. doi: 10.1016/0273-1177(94)90459-6.
The most important health effect of space radiation for astronauts is cancer induction. For radiation risk assessment, an understanding of carcinogenic effect of heavy ions in human cells is most essential. In our laboratory, we have successfully developed a human mammary epithelial cell system for studying the neoplastic transformation in vitro. Growth variants were obtained from heavy ion irradiated immortal mammary cell line. These cloned growth variants can grow in regular tissue culture media and maintain anchorage dependent growth and density inhibition property. Upon further irradiation with high-LET radiation, transformed foci were found. Experimental results from these studies suggest that multiexposure of radiation is required to induce neoplastic transformation of human epithelial cells. This multihits requirement may be due to high genomic stability of human cells. These growth variants can be useful model systems for space flight experiments to determine the carcinogenic effect of space radiation in human epithelial cells.
太空辐射对宇航员最重要的健康影响是诱发癌症。对于辐射风险评估而言，了解重离子在人体细胞中的致癌作用至关重要。在我们实验室，我们成功开发了一种用于研究体外肿瘤转化的人乳腺上皮细胞系统。从经重离子辐照的永生化乳腺细胞系中获得了生长变体。这些克隆的生长变体能够在常规组织培养基中生长，并保持贴壁依赖性生长和密度抑制特性。在用高传能线密度辐射进一步辐照后，发现了转化灶。这些研究的实验结果表明，需要多次辐射暴露才能诱导人上皮细胞发生肿瘤转化。这种多次击中的需求可能是由于人体细胞具有较高的基因组稳定性。这些生长变体可作为太空飞行实验的有用模型系统，以确定太空辐射对人上皮细胞的致癌作用。
