Tumor cell-specific gene expression by 5'-flanking DNA of murine Q5 gene in an adenoviral vector system.

Background: Regulatory DNA that would induce tumor cell-specific gene expression of arbitrary genes in human cells has been sought. We previously reported that the transcription of mouse Q5 gene was tumor-selective and hypothesized that Q5 5'-flanking DNA had a key role in tumor-selective transcription.

Materials And Methods: Isolation of 3.9 kb Q5 5'-flanking DNA was carried out and the sequence characteristics determined. Reporter plasmids, recombinant reporter adenoviruses and recombinant reporter lentiviruses were prepared that contained the Q5 5'-flanking DNA fragments of various lengths. Expression of these reporter genes was examined in various murine cells in vitro and in vivo and in various human cells in vitro.

Results: Adenovirus vectors that had Q5 5'-flanking DNA contained a regulatory region and induced tumor cell-specific gene expression not only in mouse cells but also in human cells.

Conclusion: Our newly constructed vector system could be utilized in gene therapy of human cancer.