Elgqvist Jörgen, Timmermand Oskar Vilhelmsson, Larsson Erik, Strand Sven-Erik
Department of Medical Radiation Physics, Institute of Clinical Sciences, Lund University, Lund, Sweden
Department of Medical Radiation Physics, Institute of Clinical Sciences, Lund University, Lund, Sweden.
Anticancer Res. 2016 Jan;36(1):103-9.
The purpose of the present study was to investigate the radiosensitivity of the prostate cancer cell lines LNCaP, DU145, and PC3 when irradiated with beta particles emitted from (177)Lu, and to compare the effect with irradiation using alpha particles or gamma rays.
Cells were irradiated with beta particles emitted from (177)Lu, alpha particles from (241)Am, or gamma rays from (137)Cs. A non-specific polyclonal antibody was labeled with (177)Lu and used to irradiate cells in suspension with beta particles. A previously described in-house developed alpha-particle irradiator based on a (241)Am source was used to irradiate cells with alpha particles. External gamma-ray irradiation was achieved using a standard (137)Cs irradiator. Cells were irradiated to absorbed doses equal to 0, 0.5, 1, 2, 4, 6, 8, or 10 Gy. The absorbed doses were calculated as mean absorbed doses. For evaluation of cell survival, the tetrazolium-based WST-1 assay was used. After irradiation, WST-1 was added to the cell solutions, incubated, and then measured for level of absorbance at 450 nm, indicating the live and viable cells.
LNCaP, DU145, and PC3 cell lines all had similar patterns of survival for the different radiation types. No significant difference in surviving fractions were observed between cells treated with beta-particle and gamma-ray irradiation, represented for example by the surviving fraction values (mean±SD) at 2, 6, and 10 Gy (SF2, SF6, and SF10) for DU145 after beta-particle irradiation: 0.700±0.090, 0.186±0.050 and 0.056±0.010, respectively. A strong radiosensitivity to alpha particles was observed, with SF2 values of 0.048±0.008, 0.018±0.006 and 0.015±0.005 for LNCaP, DU145, and PC3, respectively.
The surviving fractions after irradiation using beta particles or gamma rays did not differ significantly at the absorbed dose levels and dose rates used. Irradiation using alpha particles led to a high level of cell killing. The results show that the beta-particle emitter (177)Lu as well as alpha-particles are both good candidates for radionuclide-therapy applications in the treatment of prostate cancer.
本研究旨在探讨前列腺癌细胞系LNCaP、DU145和PC3在受到¹⁷⁷Lu发射的β粒子照射时的放射敏感性，并将其与使用α粒子或γ射线照射的效果进行比较。
细胞分别受到¹⁷⁷Lu发射的β粒子、²⁴¹Am发射的α粒子或¹³⁷Cs发射的γ射线照射。一种非特异性多克隆抗体用¹⁷⁷Lu标记，并用于对悬浮细胞进行β粒子照射。使用先前描述的基于²⁴¹Am源的自制α粒子辐照器对细胞进行α粒子照射。使用标准的¹³⁷Cs辐照器进行外部γ射线照射。细胞被照射至吸收剂量等于0、0.5、1、2、4、6、8或10 Gy。吸收剂量计算为平均吸收剂量。为评估细胞存活情况，使用基于四氮唑的WST - 1检测法。照射后，将WST - 1加入细胞溶液中，孵育，然后测量450 nm处的吸光度水平，以指示存活和有活力的细胞。
LNCaP、DU145和PC3细胞系对于不同辐射类型均具有相似的存活模式。在β粒子照射和γ射线照射处理的细胞之间，未观察到存活分数有显著差异，例如以DU145在β粒子照射后2、6和10 Gy时的存活分数值（平均值±标准差）为例：分别为0.700±0.090、0.186±0.050和0.056±0.010。观察到对α粒子有很强的放射敏感性，LNCaP、DU145和PC3的SF2值分别为0.048±0.008、0.018±0.006和0.015±0.005。
在所用的吸收剂量水平和剂量率下，使用β粒子或γ射线照射后的存活分数无显著差异。使用α粒子照射导致高水平的细胞杀伤。结果表明，β粒子发射体¹⁷⁷Lu以及α粒子都是前列腺癌放射性核素治疗应用的良好候选者。
