纳米分子PAMAM作为miR药物载体靶向胃腺癌的功能研究

【摘要】目的检测纳米级生物材料聚酰胺-胺（PAMAM）作为微小RNA（miR）基因投递载体对胃腺癌细胞的功能作用，为研发高效小分子靶向投递药物奠定基础。方法透析法制备叶酸（FA）/PAMAM络合物；分别以FA/PAMAM络合物和脂质体为载体转染miR-7至胃腺癌细胞株SGC-7901，荧光显微镜观察络合物转染效率，实时定量聚合酶链式反应（qRT-PCR）方法检测miR-7水平；细胞免疫荧光法检测miR-7靶基因表皮生长因子受体（EGFR）、蛋白激酶B（PKB）和细胞增殖活性抗原（PCNA）的表达；Transwell体系检测瘤细胞迁移能力。结果与脂质体相比较，FA/PAMAM络合物可显著提高SGC-7901细胞miR-7表达水平，降低瘤细胞EGFR、PKB和PCNA的水平，降低瘤细胞迁移百分率（均P＜0.05）。结论PAMAM可以作为小分子药物miR的靶向投递载体，有望进一步推动新的基因靶向药物研发。

Function Study of the Nano-Molecular PAMAM as miR Carrier Targeting Gastric Adenocarcinoma

[Abstract]Objective To study the function of the nano-molecular polyamide-amine (PAMAM) as microRNA(miR)carrier targeting gastric adenocarcinoma, and the foundation of developing an efficient delivery of small molecule drugs targeting gastric cancer thereof.MethodsThefolic acid (FA) /PAMAM comoles compound was prepared by dialysis method. After transfection of miR-7or liposomes into SGC-7901cell line, fluorescence microscope was used to detect the gene transfect efficiency. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the miR-7level. The immunocytochemistry assay was used to test the protein expressions of epidermal growth factor receptor (EGFR), protein kinase B (PKB) and proliferating cell nuclearantigen (PCNA). The transwell system was utilized to explore the migration ability of tumor cells.Results Compared with liposme, FA/PAMAN complex compound can significantly improve the level of miR-7 in SGC-7901cells，reduce the protein levels of EGFR, PKB and PCNA in SGC-7901cells, and also reduce the percentage of cancer cell migration (P＜0.05).ConclusionPAMAM can effectively transfect miR into gastric cancer cells, which is expected to become an efficient delivery of small molecule drugs.