Patent ID: 6943026

Claim:
A composition comprising a first nucleic acid construct comprising a first gene encoding an antitumor agent whose expression is controlled by a first promoter whose function is suppressed by a wild-type p53 allele in non-tumour cells relative to tumor cells in which wild-type p53 tumor suppressor function is abrogated, and a second nucleic acid construct comprising a second gene whose gene product suppresses expression of said firs gene, wherein the expression of said second gene is controlled by a second promoter comprising the sequence 5′-PuPuPuC(A/T)(A/T)GPyPyPy-3′ (SEQ ID NO:1) and whose function is up-regulated by wild type p53 in non-tumor cells relative to tumor cells in which wild-type p53 tumor suppressor function is abrogated, such that said first gene is expressed in tumor cells and suppressed in non-tumor cells.