纳米分子PAMAM作为miR药物载体靶向胃腺癌的功能研究

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

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。

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 tar-geting gastric cancer thereof. Methods The folic acid （FA）/PAMAM comoles compound was prepared by dialysis method. After transfection of miR-7 or liposomes into SGC-7901 cell line, fluorescence microscope was used to detect the gene trans-fect efficiency. Real-time quantitative polymerase chain reaction （qRT-PCR） was used to detect the miR-7 level. The immu-nocytochemistry 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 tu-mor cells. Results Compared with liposme, FA/PAMAN complex compound can significantly improve the level of miR-7 in SGC-7901 cells,reduce the protein levels of EGFR, PKB and PCNA in SGC-7901 cells, and also reduce the percentage of cancer cell migration （P〈0.05）. Conclusion PAMAM can effectively transfect miR into gastric cancer cells, which is expected to become an efficient delivery of small molecule drugs.