THE EFFECT OF LOW-DOSE RADIATION ON EPO AND VEGF OF TUMOR IN S180 SARCOMA-BEARING MICE

Objective To observe the effect of low-dose radiation(LDR) on general condition of sarcoma-bearing mice and investigate its effect on EPO and VEGF as well as its tumor inhibition.Methods Subcutaneous inoculation with S180 sarcoma cells was done in Kunming mice,which were randomized to sham-radiation(SR) group and LDR group on day 12 after tumor formation.The mice in LDR group were given 75 mGy total-body γ-ray radiation,and those in SD group received no-ray radiation.The mice in SD group were sacrificed six hours after the radiation,and those in LDR group killed at 6h(group B),12 h(group C),24 h(group D),48 h(group E) and 72 h(group F),respectively.The tumor weight was measured,and the expressions of EPO and VEGF were detected immunohistochemically.Results The tumor weight of mice in groups E and F was statistically different compared to that in group A(F=3.90;q=4.525,4.551;P0.05).A comparison between the positive EPO in tumor of group A and that of groups E and F showed significant difference(F=16.26;q=6.600,7.554;P0.01);the VEGF expressions in LDR groups were different as compared with that in group A(F=47.27,q=2.777-14.668,P0.05).Conclusion LDR can lower the weight of tumor,indicating that LDR,in some extent,inhibit the expressions of EPO and VEGF,thus restrain angiogenesis,the growth and metastasis of the tumor.