[Mannatide enhances the efficacy of fractionated and unfractionated radiotherapy in mice bearing Lewis lung cancer].
OBJECTIVE
To investigate the effect of mannatide injection (MI) in enhancing the efficacy of radiotherapy in two therapeutic schedules in mice bearing Lewis lung cancer.


METHODS
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.


RESULTS
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).


CONCLUSIONS
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.
Department of Radiotherapy, Zhengzhou University, Zhengzhou, China. fanruitai@126.com
Rui-tai
RT
Fan
Yong
Y
Hu
Jun-qi
JQ
Liu
Jing-jing
JJ
Zhang
Rui
R
Song
Hao
H
Gu
D000818:Animals; D001688:Biological Products / Q000627:therapeutic use*; D018827:Carcinoma, Lewis Lung / Q000188:drug therapy* / Q000532:radiotherapy*; D003131:Combined Modality Therapy; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D011838:Radiation-Sensitizing Agents / Q000627:therapeutic use*; D013291:Streptococcus
D001688:Biological Products; D011838:Radiation-Sensitizing Agents