Radioresponsiveness of human glioma, sarcoma, and breast cancer spheroids depends on tumor differentiation.

摘要: Abstract Purpose: Differences in the intrinsic radiosensitivity within and between different tumor classes have been noticed for human cell lines using clonogenic assay. By far, most of studied up to now were derived from poorly differentiated tumors. In this study, influence differentiation on radiation doses necessary control 50% small oxic spheroids (SCD 50 ) was determined. Evidence a distinct dependence radioresponsiveness progression provides background an investigation underlying mechanisms. Methods Materials: Spheroids aggregated 1000–1500 cells agarose coated 24 multi-well plates. Their diameters ranged 156 405 μm, depending line. irradiated with graded 60 Co single spheroid as end point minimum follow-up period 3 months. Results: Cell three low grade gliomas 10 malignant The group mean SCD values 6.1 ± 1.6 Gy 13.1 3.3 Gy, respectively. Four 2 soft tissue sarcomas had value 6.2 0.5 one undifferentiated sarcoma line 11.0 Gy. Three well-differentiated breast cancer expressed adhesion molecule E-cadherin, epitheloid morphology monolayer culture, estrogen receptor positive or contact inhibited multicellular spheroids. Two fibroblastoid marker negative. former 10.5 1.0 while that 14.8 2.8 Analysis variance revealed significant effect type well dedifferentiation after irradiation fraction 2Gy/fraction. surviving fractions at (SF2), obtained rates fractionation schedules by approximation linear quadratic model assuming Poisson statistics significantly dependent ( p = 0.001, ANOVA F-test) but not 0.27). αβ ratios did depend 0.08, F-Test) increased 0.03). Conclusion: is suitable measuring very colony forming efficiencies. Tumor important factor recovery capacity cells.