超声造影剂在肝癌基因治疗中的靶向性实验研究

目的 探讨结合了肝细胞配体的超声造影剂在超声辐照下介导目的 基因转染肝癌细胞的可行性,寻找一种新的基因靶向导入方法.方法 制备肝细胞表面特异性配体半乳糖基化多聚赖氨酸(GPLL),并对产物进行红外光谱分析.将c-myc基因反义寡核苷酸(ASODN)、G-PLL与SonoVue微泡三者偶联,在超声波介导下,促使c-myc ASODN转染人肝细胞癌SMMC-7721细胞及肺腺癌A-549细胞(作对照),实验结束后行半定量逆转录聚合酶链式反应(RT-PCR)以观察不同组问c-myc基因的表达情况.结果 超声介导微泡破裂可增加c-myc ASODN在SMMC-7721细胞和A-549细胞中的表达;SMMC-7721细胞加入G-PLL组中c-myc基因表达水平显著降低,差异有统计学意义(P＜0.01),而A-549细胞中加入与未加入G-PLL组间c-myc基因表达量的差异无统计学性意义(P＞0.05).结论 超声介导微泡造影剂破裂的方法可促进基因的转染,而超声联合肝细胞受体介导的微泡造影剂则更具有肝细胞靶向性,能有效地促进目的 基因在肝癌细胞中的表达,为肝癌基因治疗提供了新的途径.

Experimental study on targeted ultrasound contrast agent in the gene therapy of liver cancer

Objective To develop a novel approach of transfecting the objective gene tagetedly mediated by ultrasound contrast agent conjugated ligand of hepatocyte with ultrasound irradiation.Methods C-myc ASODN and galactosylation polylysine which was specific ligand of hepatocyte and the surface of SonoVue microbbule were coupled by electrostatic interaction.Liver cancer cells SMMC-7721 and lung cancer cells A-549 were transfected with c-myc ASODN in vitro by ultrasound-mediated microbubble destruction.The c-myc gene expression of SMMC-7721 cells and A-549 cells was detected by semiquantitative RT-PCR.Results Ultrasound mediated microbubble destruction can enhance antisense c-myc gene expression in SMMC-7721 cells and A-549 cells.C-myc expression was decreased in transfected SMMC-7721 cells with G-PLL(P＜0.01).C-myc expression in A-549 cells with G-PLL was similar to without G-PLL(P＞0.05).Conclusions Ultrasound mediated microbubble destruction method can enhance gene transfection,ultrasound and hepatocellular receptor-mediated microbubble destruction have target to liver cells,in which the gene expression level was increased.It is a promising method in gene therapy of liver cancer.