Expression Patterns of Adenoviral Green Fluorescent Protein Gene in Human Cancer Cell Lines

Many methods have been developed for more efficient gene delivery and expression in human cells. A number of studies have been performed in achieving successful gene delivery and expression conditions. We investigated differential gene expression patterns after delivery adenoviral vector containing green fluorescent protein(GFP) gene into human cancer cell lines. We constructed recombinant adenoviral Ad-CMV-GFP containing CMV promoter and GFP gene. The efficiency of gene expression was assessed by observation GFP expressing cells using fluorescent microscopy after transfer of Ad-CMV-GFP in concentrations of 0.1μl. 1μl. 10μl. At first, we evaluated expression patterns of gene in several human cancer cell lines, gastric adenocarcinoma cell line AGS was showed high level of GFP expression compared with colorectal adenocarcinoma cell line HT-29. After transfer 0.1μl of Ad-CMV-GFP in AGS, we could found that GFP expression cells were observed in next day and highly increased 2 days. While, small number of GFP expressing cells were examined in HT-29 and SNU-C4. Therefore, these data showed that AGS was expressed the highest level of GFP and almost AGS cells seems to express GFP in concentration of 1μl of Ad-CMV-GFP. GFP expression pattern in HT-29 reveal that expression was low in next day after gene transfer but significantly increase expression level in 2 days. In case of SNU-C4, GFP expression increased with increasing concentration of Ad-CMV-GFP and transfer times. For examine effects of transfer times in small amount gene, we transfer in concentration of 0.1μl Ad-CMV-GFP and detected GFP expression patterns after 2 days or 4 days. As a result, expression level of GFP in AGS was increase about 2 fold after 4 days compared with 2 days, but any difference of GFP expression levels were not showed in HT-29 and SNU-C4. Our study suggested that adenovirus was very efficient gene transfer vector for gene expression in human cancer cell lines. In addition to, we also demonstrated that gene expression patterns was dependent on each human cell lines. Therefore, further studies will be needed to confirm the optimum conditions for efficient gene delivery and expression in each target cell lines with consideration to cellular properties.