Effect Of Hsv-tk Gene Expression In Residual Liver Cancer By Different Microbubble Concentration After HIFU

Objective: To get the best contrast agent concentration through observing the TK gene expression in residual liver tissue impacted by different concentrations of lipid bubbles loaded HSV1-TK gene after high intensity focused ultrasound(HIFU) treatment of VX2 liver cancer in rabbit.Methods: Twenty rabbits borne VX2 tumor After HIFU were randomly divided into 4 groups, Group A: The concentration of microbubbles loaded gene was 0.025 mg/ml; Group B: The concentration of microbubbles loaded gene was 0.05 mg/ml; Group C: The concentration of microbubbles loaded gene was 0.075 mg/ml; Group D: The concentration of microbubbles loaded gene was 0.1 mg/ml. 5 ml/kg microbubbles loaded gene injected via rabbit ear vein and ultrasound irradiation, ultrasound was used at 300 KHz, 2 W/cm2, irradiation 10 s, interval 10 s, a total of 20 min. All rabbits were killed after 48 h, TK gene expression was detected by RT-PCR. TK protein expression was detected by immunohistochemistry.Results: The results of Immunohistochemistry showed the TK expression of group B,C,D than group A(p<0.05), TK expression of group C,D than group B(p<0.05), TK expression of group C and group D was not significant(p>0.05). The results of RT-PCR showed the TK gene expression of group B,C,D than group A(p<0.05), TK gene expression of group C,D than group B(p<0.05), TK gene expression of group C and group D was not significant(p>0.05).Conclusions: When concentration of microbubbles loaded gene less than 0.075 mg/ml, the expression of TK mRNA and protein dependent on concentration.When concentration of microbubbles loaded gene more than 0.075 mg/ml, the gene expression has no correlation between the concentration of microbubbles. Therefore, the best concentration of microbubbles loaded gene is 0.075 mg/ml. It provides a reliable experimental evidence for follow-up study.