Synergistic therapeutic effect in gastric cancer cells produced by oncolytic adenovirus encoding Drosophila melanogaster deoxyribonucleoside kinase.

Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK), a novel suicide kinase, was applied as a cancer gene therapeutic approach. To improve the antitumor effect of Dm-dNK and its substrate with the selectivity and safety control in consideration, the conditionally replicative gene-viral system ZD55-dNK, which includes the replicationselective adenovirus ZD55 armed with the Dm-dNK, was used to further explore the potential of this approach. When ZD55-dNK was combined with BVDU it produced a synergistic inhibitive effect of adenovirus replication in vitro while maintaining specific cancer cell killing activity. From a clinical standpoint, this approach is promising for its considerably low toxic side effects.