载TK基因PEG-PEI Fe_3O_4纳米磁流体体外肿瘤细胞抑制的研究

Study of encapsulation of suicide gene in PEG-PEI/Fe_3O_4 nano-magnetic fluid and its characteristics in vitro

目的:研究载TK基因PEG-PEIFe3O4纳米磁流体体外肿瘤细胞抑制特性。方法:以RT-PCR方法鉴定其在各细胞系中mRNA水平上的表达状况。采用MTT法研究载TK基因纳米颗粒体外抑制肿瘤细胞的生长作用。结果:PEG-PEIFe3O4纳米磁流体能有效的转染pAFP-TK进入AFP阳性的HepG2细胞,并在细胞内得以正常表达。MTT法显示,AFP阳性的细胞在转染pAFP-TK后对GCV的敏感性大大提高,细胞存活率明显下降。结论:PEG-PEIFe3O4纳米磁流体能高效转染pAFP-TK质粒进入细胞,并在AFP阳性肝癌细胞中获得特异性表达,加用GCV后,还可高效杀伤AFP阳性肝癌细胞。

AIM： To prepare PEG-PEI Fe3O4 nano-magnetic fluid and invest its characteristics. METHODS： PEG-PEI Fe3O4 nano-magnetic fluid was prepared by chemical co-deposition as gene delivery vector. Then DNA of plasmid pAFP-TK was wrapped into PEG-PEI Fe3O4 nano- magnetic fluid. At the same time, we invest its characteristics with MTT assay. RESULTS： PEG-PEI Fe3O4 nano-magnetic fluid-DNA complexes could protect the DNA from degradation of DNasel, serum and sonication. AFP positive cells transfected by pAFP-TK were highly sensitive to the GCV treatment, and the survival of cells declined obviously. HSV-TK/GCV suicide gene therapy system had direct cell toxicity. CONCLUSION： This new target strategy of pAFP-TK/GCV suicide gene therapy system in which PEG-PEI Fe3O4 nano-magnetic fluid are used as gene delivery vectors explores a promising area for AFP positive HCC and associated carcinoma therapy.