Efficacy of Gefitinib Combined with 125I Radioactive Particles in the Treatment of Transplanted Lung Cancer Tumors in Nude Mice

Abstract

To investigate the efficacy of gefitinib combined with iodine-125 (125I) radioactive particles in the treatment of transplanted tumors of the lung cancer cell line A549 in nude mice. Twenty-four nude mice were inoculated with A549-luc human lung adenocarcinoma cells stably expressing luciferase. The tumor size was approximately 8-10mm after 20days. The mice were randomly divided into four groups: a control group (n = 6), an 125I particles group (n = 6), a gefitinib group (n = 6) and a gefitinib combined 125I particles implantation group (n = 6). Tumor growth was observed, and changes in tumor size were continuously measured. Bioluminescence imaging was used to detect the bioluminescence activity of human lung adenocarcinoma A549-luc cells containing the luciferase reporter gene in vivo. After 35days, the nude mice were sacrificed, and a tumor growth curve was drawn. Before treatment, the tumor volumes of the four groups were not significantly different. The tumor volume difference was statistically significant in the four groups (control group, 125I radioactive particles, gefitinib group and combined drug group) at 5weeks after treatment (F = 10.305, P < 0.05). The tumor size in the gefitinib combined with 125I particles group was significantly smaller than that in the gefitinib, 125I particles and control groups and significantly smaller than that before treatment. There was no significant difference in the bioluminescence signal intensity between the four groups before treatment. The numbers of biofluorescence photons difference were statistically significant in the four groups (F = 28.975, P < 0.05). The bioluminescence signal intensity in the gefitinib combined with 125I particles group was significantly lower than that in the 125I particles, gefitinib and control groups and significantly lower than that before treatment. Gefitinib combined with 125I radioactive particles brachytherapy can significantly inhibit tumor growth.