MicroRNA基因递送系统抗激素非依赖型前列腺癌增殖作用研究

目的：采用分枝状聚乙烯亚胺（BPEI）、线型的聚乙烯亚胺（LPEI）和树枝状聚合物聚酰胺-胺（PAMAM）与具有抑制激素非依赖型前列腺癌细胞PC3增殖的miRNA-15a和miRNA-16-1质粒结合，构建了MicroRNA基因递送系统。考察形成的三种纳米复合物的粒径、zeta电位、细胞内摄取，以及对PC3细胞的抑制作用。方法：利用粒径分析仪测定形成的三种纳米复合物的粒径和电位，凝胶电泳实验测定三种材料对miRNA的结合能力; 利用FAM标记的NC-miRNA考察PC3细胞对三种复合的摄取情况；通过CCK8 法测定三种材料与miRNA-15a和miRNA-16-1形成的复合物对PC3细胞的抑制作用；PCR法测定三种材料与miRNA-15a和miRNA-16-1结合后对PC3细胞中Bcl-2，Cylin D1和Wnt3a表达的阻滞作用。结果：BPEI，LPEI和PAMAM三种材料与miRNA可结合形成稳定的纳米级复合物，在N/P=5时，PC3细胞对BPEI/miRNA-FAM的摄取高于LPEI/miRNA-FAM和PAMAM/miRNA-FAM，具有统计学意义（P<0.01）。BPEI、LPEI和PAMAM都可以携带miRNA-15a和miRNA-16-1进入PC3细胞，并且阻滞PC3细胞中Bcl-2，Cylin D1和Wnt3a蛋白的表达。结论：BPEI，LPEI和PAMAM三种材料包裹miRNA-15a和miRNA-16-1可对激素非依赖型前列腺癌细胞PC3细胞产生抑制作用。并可以有效阻滞PC3细胞中Bcl-2，Cylin D1和Wnt3a蛋白的表达。

MicroRNA delivery system inhibits proliferation of androgen-independent prostate cancer

Objective To prepare a microRNA (miRNA) delivery system using the branched polyethyleneimine (BPEI), linear polyethylenimine (LPEI) and polyamidoamine dendrimers (PAMAM) loaded with miRNA-15a and miRNA-16-1, which can inhibit prostate cancer PC3 cell proliferation, and to examine the zeta potential, intracellular uptake, and the inhibition effect on PC3 cells of the three constructed nano-complexes. Methods Particle size analyzer was used to determine the size and potential of the three kinds of nano-complexes, and the miRNA affinity capability of them was determined by agarose gel electrophoresis retardation assay. The uptake efficiency of the nano-complexes by PC3 cells was examined by NC-miRNA labeled with FAM. CCK8 method was used to determine the inhibitory effect of the nano-complexes loaded with miRNA-15a and miRNA-16-1 against PC3 cells, and PCR was used to analyze their inhibitory effect on expression of Bcl-2, Cylin D₁ and Wnt3a gene in PC3 cells. Results BPEI, LPEI and PAMAM loaded with miRNA could form stable nano-complexes. When N/P=5, the intracellular uptake of BPEI/miRNA-FAM by PC3 cells was significantly higher than that of LPEI/miRNA-FAM and PAMAM/miRNA-FAM (P<0.05). BPEI, LPEI and PAMAM could all carry miRNA-15a and miRNA-16-1 into PC3 cells and block Bcl-2, Cylin D₁ and Wnt3a expression in PC3 cells. Conclusion BPEI, LPEI and PAMAM loaded with miRNA-15a and miRNA-16-1 can suppress proliferation of prostate cancer PC3 cells and block Bcl-2, Cylin D₁ and Wnt3a expression.