Preparation of microsphere encapsulating recombinant TIMP-1 adenovirus and its inhibitory effects against hepatocellular carcinoma cells / 中国肿瘤生物治疗杂志

ABSTRACT

Objective:Toprepare poly-DL-lactide-poly (PELA) microspheres encapsulating recombinant tissue inhibitors of metalloproteinase-1 (TIMP-1) adenovirus, and to investigate their effects on the proliferation of hepatocellular carcinoma HepG2 cells. Methods: The microsphere was constructed by encapsulating recombinant adenovirus containing TIMP-1 in biodegradable PELA. The diameter of the microsphere, quantity of virus encapsulated, loading rate, and releasing kinetics were measured. HepG2 cells were infected with the microspheres; the infection efficiency was examined by fluorescent microscope; and the ultrastructure was observed by TEM. The expression of TIMP-1 mRNA in HepG2 cells was examined by semi-quantitative RT-PCR, and the proliferation of HepG2 cells was detected by MTT assay. Results: The microsphere encapsulating recombinant TIMP-1 adenovirus was successfully constructed, with its diameter, entrapment efficiency, and virus loading rate being 1.965, 60.0%, and 10.5×10~8/mg, respectively. About 60% of the viruses were released within 120 h, and the total releasing time was longer than 240 h. Infection with rAdTIMP-1 PELA microsphere efficiently induced TIMP-1 expression in HepG2 cells, and significantly inhibited the proliferation of HepG2 cells, with the inhibitory rate being 47%. Conclusion: PELA microsphere encapsulating recombinant TIMP-1 adenovirus can markedly inhibit the proliferation of HepG2 cells, which provides an experimental basis for the combining macromolecular chemistry and gene therapy for treatment of hepatocellular carcinoma.