【摘要】 目的观察两种人恶性肿瘤细胞-人肝癌细胞SMMC-7721和人黑色素瘤细胞A375对高LET12C6+离子和γ射线照射的敏感性及分次效应,观察重离子治疗肿瘤的可行性及优势。方法以两种体外培养的来源于人体不同组织的具有高辐射抗性的恶性肿瘤细胞为实验对象,分别进行12C6+和γ射线0~6Gy内不同剂量点的单次和分次照射,采用克隆存活法统计细胞的存活分数。结果无论是单次还是分次照射,12C6+照射后两种细胞的存活分数均明显低于γ射线照射的细胞,而且重离子的分次效应明显降低。结论结果显示重离子在肿瘤治疗中的两个重要优势,即具有高的肿瘤杀伤力和低的分次效应,显示重离子照射引发的低修复现象,可使肿瘤放疗具有更高的效率。更多还原

【Abstract】 Objective We should be wise to the feasibility and advantages of tumor therapy with heavy ions by observing the radiosensitivity and the effect of fractional irradiation of two kinds of malignant human tumor cell lines which were respectively irradiated with ⁶⁰Co γ-rays and ¹²C⁶⁺ ions with high LET.Methods We chose two kinds of malignant human tumor cell line which derived from different tissues and had low radiosensitivity,namely A375 and SMMC-7721.After respectively irradiated with ⁶⁰Co γ-rays and ¹²C⁶⁺ in dose range 0～6Gy,the survival fractions of single irradiation and fractional irradiation were studied by colony-formation assays.Results The results showed that: as to each cell lines involved in the assay,the survival fractions of cells irradiated with ¹²C⁶⁺ were much lower than that of cells irradiated with γ-rays not only when singly irradiated but also when fractionally irradiated.Which was more fascinating was that the effect of fractional irradiation was impaired to both two cell lines when irradiated with ¹²C⁶⁺.Conclusion The assay showed some captivating properties of ¹²C⁶⁺ in tumor therapy that ¹²C⁶⁺ could kill tumor cells more efficiently than γrays,as well as ¹²C⁶⁺ may lead a weakened repair which would make the therapy more efficient.更多还原