Low Doses Of Radiation On Mice Bearing S180 Sarcoma Tumor Tissue Mmp-2 And Timp-2 Expression

Objective To observe the effect of low-dose radiation (LDR) on daily condition of mice and its tumor-inhibition effect; to study the effect of low-dose radiation on MMP-2 and TIMP-2 of tumor in S180 sarcoma-bearing-mice; to investigate further the mechanism of action of low-dose radiation.Method The subcutaneous transplantable tumor model of S180 sarcoma-bearing-mice in Kunming stain mice were established and then were divided at random into sudo-shaming group(N) and the LDR group; a week after implantation,the mice in group LDR were given 75mGy total-body y-ray radiation. The mice were sacrificed on 12h(group LDR-12h),24h(group LDR-24h),48h(group LDR-48h),72h(group LDR-72h) respectively, observed tumor weight, and then detected the MMP-2 expression and TIMP-2 expression in tumor by P-V immunohistochemical method.Results The tumor growth was significantly slowed down in LDR group (t=2.19,P<0.05). After the low dose radiation, the difference of TIMP-2 expression between sudo-shaming group and LDR group is not significant (P>0.05). The decrease of MMP-2 expression is significant statistically in group LDR-24h(u=2.15,p<0.05) and group LDR-48h(u=2.04,p<0.05) in contrast to that in group N.Conclusion The growth of tumor was suppressed significantly after low dose total-body radiation, and the expression MMP-2 was reduced.