Overview of Radiosensitivity of Human Tumor Cells to Low-Dose-Rate Irradiation

摘要: Purpose We compared clonogenic survival in 27 human tumor cell lines that vary genotype after low-dose-rate (LDR) or high-dose rate (HDR) irradiation. measured susceptibility to LDR-induced redistribution the cycle eight of these lines. Methods and Materials up 96 hours LDR (0.25 Gy/h) with HDR irradiation (50 Gy/h). Using flow cytometry, we as a function time during Results Coefficients describe both segregate into four radiosensitivity groups associate genotype: mutant (mut)ATM, wild-type TP53, mutTP53, an unidentified gene radioresistant glioma cells. The correlates at lower doses (∼2 Gy HDR, ∼6 LDR), but not higher (HDR > 4 Gy; 6 Gy). loss changes approximately 24 hours; TP53 cells become more resistant mutTP53 sensitive. Redistribution induced by also hours. Conclusions Radiosensitivity is dependent. Analysis coefficients cellular segregates statistically distinct groups, each associating specific genotypes. Changes are strongly Our data establish genotype-dependent time-dependent model predicts survival, explains inverse dose-rate effect, suggests possible clinical applications.