Schueller Patrick, Puettmann Sylvia, Micke Oliver, Senner Volker, Schaefer Ulrich, Willich Normann
Department of Radiotherapy and Radiation Oncology, University Hospital of Muenster, Germany.
Anticancer Res. 2004 Sep-Oct;24(5A):2913-7.
A radioprotective effect of low selenium doses on normal tissue and a possible radiosensitization of tumor cells at higher concentrations have been previously suggested. However, systematic experimental and clinical data are scarce.
C6 cells were cultured for 14 days at different selenite concentrations (0 microM, 2 microM, 3 microM and 3.6 microM) and irradiated with 0 Gy to 20 Gy. Plating efficiency and survival were determined using the colony assay.
The overall radiosensitivity was low (D0,control=6.1 Gy). Irradiated cells exposed to increasing selenite concentrations showed a lower plating efficiency and, for doses > 2 Gy, a lower survival than the control. For Se concentrations of 0 microM, 2 microM and 3 microM, respectively, SF2 amounted to 0.72, 0.48 and 0.46, and SF5 to 0.37, 0.25 and 0.12. Student's t-test yielded a significant difference between the 0 microM and 3 microM curves at 5 Gy (p=0.02) and 10 Gy (p=0.009).
Our experiments suggest a radiosensitizing effect of selenite in glioma cells at concentrations of 2-3 microM.
先前有研究表明，低剂量硒对正常组织具有辐射防护作用，而在较高浓度下可能会使肿瘤细胞产生放射增敏作用。然而，系统的实验和临床数据却很匮乏。
将C6细胞在不同亚硒酸盐浓度（0微摩尔/升、2微摩尔/升、3微摩尔/升和3.6微摩尔/升）下培养14天，然后用0 Gy至20 Gy的剂量进行照射。使用集落形成试验测定接种效率和存活率。
总体放射敏感性较低（对照组D0 = 6.1 Gy）。随着亚硒酸盐浓度升高，照射后的细胞接种效率降低，且对于剂量>2 Gy的情况，其存活率低于对照组。对于硒浓度分别为0微摩尔/升、2微摩尔/升和3微摩尔/升的情况，SF2分别为0.72、0.48和0.46，SF5分别为0.37、0.25和0.12。学生t检验显示，在5 Gy（p = 0.02）和10 Gy（p = 0.009）时，0微摩尔/升和3微摩尔/升曲线之间存在显著差异。
我们的实验表明，浓度为2 - 3微摩尔/升的亚硒酸盐对胶质瘤细胞具有放射增敏作用。
