Mannatide enhances the efficacy of fractionated and unfractionated radiotherapy in mice bearing Lewis lung cancer / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of mannatide injection (MI) in enhancing the efficacy of radiotherapy in two therapeutic schedules in mice bearing Lewis lung cancer.</p><p><b>METHODS</b>C57BL/6 mice bearing Lewis lung cancer xenograft were assigned randomly into control group, fractionated schedule (FS) group, nonfractionated schedule (NFS) group, MI group, FS+MI group, and NFS+MI group (n=10). MI (4.5 mg/kg) or saline was given intraperitoneally for 14 consecutive days in the corresponding groups. Radiation with 8 MeV electron beam was delivered in a single 4 Gy dose in NFS and in 4 fractions (total dose 4 Gy) in FS. Tumor inhibition rate and the spleen and thymus index were calculated after the treatments.</p><p><b>RESULTS</b>MI significantly enhanced the efficacy of radiotherapy with a tumor inhibition rate reaching 70% in FS+MI group (P<0.01). FS resulted in a significantly higher tumor inhibition rate than NFS (P<0.05), but the rates were comparable between FS+MI and NFS+MI groups. The spleen index and thymus indices were significantly higher in FS+MI and NFS+MI groups than in FS and NFS groups (P<0.05).</p><p><b>CONCLUSION</b>MI can enhance the efficacy of radiotherapy with different therapeutic schedules in mice bear Lewis lung cancer, and MI plus fractionated radiation produces the optimal effect.</p>