Experimental study of 125I seeds inhibiting angiogenesis of transplanted hepatocellular carcinoma / 中华放射医学与防护杂志

ABSTRACT

Objective:To investigate the effect of radioactive 125I seed on angiogenesis of subcutaneously transplanted hepatocellular carcinoma in nude mice and underlying mechanism. Methods:The subcutaneous transplanted tumor model of human hepatocellular carcinoma Huh7 cells was established in nude mice. Twelve nude mice were randomly divided into observation group and control group with 6 mice in each group. The 125I seed with activity of 2.96×10 7Bq was implanted into the transplanted tumor of observation group and another with 0 Bq as control group, respectively. The volume of the transplanted tumor was measured every 4 d and the growth curve of the tumor was recorded. The microvessel density (MVD) of the transplanted tumor was evaluated by immunohistochemical detection of CD31. VEGF-A and HIF-1α protein and mRNA were detected by immunohistochemistry and RT-PCR, respectively. Results:The growth rate of tumor in the observation group was slower than that in the control group, and the difference of tumor volume between two groups at 12 d after 125I seed implantation was significantly different( t=3.167, P<0.05). At 28 d after transplantation, the tumor volumes of control and observation group approached to (963.61 ± 89.56) mm 3and (602.10±75.98) mm 3, respectively. The MVD of the observation group was significantly lower than that of the control group ( t=6.361, P<0.05). The relative expression of VEGF-A and HIF-1α mRNA in the observation group was significantly lower than that in the control group ( t=10.480, 6.414, P<0.05). Protein expression levels of VEGF-A and HIF-1α in the observation group were lower than those in the control group ( t=10.890, 12.250, P<0.05). Conclusions:Radioactive 125I seed can inhibit the growth of HCC xenografts by reducing tumor microvessels, which may be related to the decrease of VEGF-A and HIF-1α expression.