Evaluation Of Apoptosis Of Tumor Cell By Tracer Of ¹⁸F-ML-10

Objective:The use of cisplatin-induced apoptosis in human lung adenocarcinoma A549 cell established apoptotic model. In this model, intake of F-ML-10 to apoptotic cells was detected. A biology distribution of 18F-ML-10 in healthy kunming mice were performed. To observe intake of 18F-ML-10 in tumor-burdened mice, PET imaging was performed. Furthermore, evaluate the feasibility of early detection of tumor response after therapy by 18F-ML-10.Methods:We cultured human lung adenocarcinoma A549 cells in vitro. The apoptosis rate was measured by Annexin v-FITC/PI quantitative assay after chemotherapy, as well as intake of 18F-ML-10 was measured.25 healthy mice were randomly divided into 5 groups, intake of various organs of mice at different time points to evaluate the biodistribution was detected after injection of 18F-ML-10. Tumor bearing model of mice was successively prepared, and the mice were performed by PET imaging at different time point after injection of 18F-ML-10.6 tumor-burdened mice were divided into control group and experimental group. Irradiation to tumor location were performed by gamma rays (5Gy) in experimental group, PET imaging were measured after waiting for 24h.Results:The apoptosis rate were ranged from 23.02±3.37 to 37.31±2.48% after chemotherapy by different cisplatin dosage, differences have statistical significance compared to the control group; The intake levels were ranged from 1.91±0.21 to 3.08±0.20%ID/105 after chemotherapy by different cisplatin dosage. The apoptosis rate were ranged from 0.64±0.26 to 63.10±14.00% after chemotherapy by different cisplatin action time, differences have statistical significance compared to the control group; The intake levels were ranged from 0.07±0.01 to 4.97±1.03%ID/105 after chemotherapy by different cisplatin action time. The apoptosis rate and the intake of 18F-ML-10 were the linear correlation. In biological distribution in kunming mice, the blood concentrations of F-ML-10 was quickly achieved maximum, and rapid distribution to the whole body organs, mainly from urine excreted by the kidney. PET imaging results showed that the maximum of intake levels was 0.28±0.10%ID/g after the injection of 18F-ML-10 of 60 minutes. After radiotherapy of Tumor-burdened tumors in mice, the intake of 18F-ML-10 was 1.25±0.13%ID/g and T/M was 5.95.Conclusion:Cisplatin induced apoptosis in human lung adenocarcinoma A549 cells, the rate of apoptosis was associated with cisplatin dosage and action time, there were the linear correlation between the intake of 18F-ML-10 and the rate of apoptosis. The best time of detected the intake of 18F-ML-10 was 60-90min after the injection. There was a preferred biological distribution in kunming mice. PET imaging demonstrated an clearly show the outline of the tumor, and partial accumulation in tumor tissue in a tumor-burdened mice. There may be certain feasibility for monitoring radiation effect by 18F-ML-10 in mice.