Abstract:

Objective To investigate the application of ¹⁸F-fluoro-3´-Deoxy-3´-L-fluorothymidine (¹⁸F-FLT) and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) in evaluation of tumor proliferation of nude mouse models of chronic myelogenous leukemia(K562 cell lines). Methods ¹⁸F-FLT was synthesized and K562 cells were traditionally cultured. The in vitro experiment of ¹⁸F-FLT and ¹⁸F-FDG uptake assay was performed in K562 cells at 15 min, 30 min, 60 min and 120 min. After tumorbearing mouse models of leukemia were successfully established by injection of K562 cells, positron emission computed tomography (PET) was performed 30 min, 60 min and 120 min after injection of ¹⁸F-FLT and ¹⁸F-FDG. The region of interest was drawn over the tumor and background to calculate the ratio of tumor to non-tumor (T/NT). Results High-performance liquid chromatography indicated that the radiochemical purity of ¹⁸F-FLT was over 95% within 6 h. Pathological examination revealed that tumor-bearing nude mouse models of leukemia were successfully established by subcutaneous inoculation of K562 cells. A significantly higher uptake of ¹⁸F-FLT than that of ¹⁸F-FDG was observed in K562 cells in the tracer uptake experiment at various time points (P＜0.05). And ratios of T/NT of ¹⁸F-FLT PET were significantly higher than those of ¹⁸F-FDG PET at different time points after injection (P＜0.05). Conclusion Compared with ¹⁸F-FDG, ¹⁸F-FLT may have better performance in evaluation of tumor proliferation of nude mouse models of leukemia.

Key words: thymidine, deoxyglucose, tomography, emission-computed, leukemia, mice, nude