Construction of recombinant adenovirus vector expressing EGFP gene specifically in AFP producing liver cancer cells

AIM: To construct a recombinant adenovirus vector carrying AFP promoter to specifically express a targeting gene in hepatocellular carcinoma HepG2 cells. METHODS: Based on the Adeno-X~TM Expression system, the CMV promoter was replaced by a 300 bp a-fetoprotein promoter. The EGFP(enhanced green fluorescent protein) gene as a report gene was inserted to the multiple-cloning site(MCS). The normal liver LO2 cells, hepatocellular carcinoma HepG2 cells and HeLa cells were infected by the recombinant adenovirus, respectively. Northern blotting and fluorescence microscope were used to detect the transcription level of EGFP gene and its protein expression, respectively. RESULTS: Northern blotting showed that the target gene was markedly transcribed in HepG2 cells, but slightly in LO2 and HeLa cells. Under the fluorescence microscope, strong EGFP expression was seen in HepG2 cells but very weakly in HeLa and LO2 cells. CONCLUSION: Under the control of the 300 bp human AFP promoter, the target gene carried by the recombinant adenovirus was expressed in the AFP-producing HepG2 cells at a very high level, but not or very weakly in AFP negative cells. This adenovirus system can be used as a new, potent and specific approach for the gene-targeting therapy for the AFP producing primary hepatoma. [