【摘要】 为考察恶性肿瘤细胞的分次照射效应,选取5种具有高辐射抗性的恶性肿瘤细胞系分别进行单次和分次的γ射线照射,比较它们的剂量存活曲线的α/β值及D50、D10值。结果表明,D50的分次照射效应的高-低排列次序为:SMMC-7721、HeLa、A549、HT29和PC3细胞,D10的分次照射效应的高-低排列次序为:SMMC-7721、HeLa、PC3细胞、A549和HT29细胞。5种肿瘤细胞的α/β值的低-高排列次序为:SMMC-7721、PC3、HeLa、A549和HT29细胞;除PC3细胞外,其余四种细胞的辐射敏感性和分次效应均与α/β值相关,α/β值越小,细胞越不敏感且分次效应越明显。不同组织来源的肿瘤细胞的辐射敏感性差异较大,其修复功能和分次照射的生物学效应也有相应的差异,部分肿瘤细胞的辐射敏感性和分次照射的生物学效应与其修复能力相关,单次照射剂量存活曲线的参数α/β值可作为检测肿瘤细胞的辐射敏感性和分次照射的生物学效应的标准。更多还原

【Abstract】 Five kinds of malignant human tumor cells, i.e. SMMC-7721, HeLa, A549, HT29 and PC3 cell lines, were irradiated by 60Co γ-rays to 1—6 Gy in a single irradiation or two irradiations of half dose. The radiosensitivity was compared with the dose-survival curves and D50 and D10 values. Differences in the D50 and D10 between the sin-gle and fractional irradiation groups showed the effect of fractional irradiation. Except for PC3 cells, all the cell lines showed obvious relationship between radiosensitivity and biologic effect of fractional irradiation and the α/β value . A cell line with bigger α/β was more radiation sensitive, with less obvious effect of fractional irradiation. The results in-dicate that there were obvious differences in radiosensitivity, repair ability and biologic effect of fractional irradiation between tumor cells from different tissues. To some tumor cell lines, the relationship between radiosensitivity, bio-logic effect of fractional irradiation and repair ability was attested. The α /β value of single irradiation can be regarded as a parameter to investigate the radiosensitivity and biologic effect of fractional irradiation of tumor cells.更多还原