Enhanced therapeutic effect of cisplatin on the prostate cancer in tumor-bearing mice by transfecting the attenuated Salmonella carrying a plasmid co-expressing p53 gene and mdm2 siRNA

• Prostate cancer urgently needs an efficient therapy.
• Cisplatin with p53/MDM2 gene therapy synergistically inhibits prostate cancer.
• The synergistic therapy is related to increased Bax-associated apoptotic cell death.

Prostate cancer urgently needs an efficient therapy. Here we demonstrated that cisplatin combined with gene therapy by transfecting the attenuated Salmonella that carry a plasmid containing p53 gene and MDM2 siRNA provided a super-synergistic effect on the inhibition of prostate cancer growth in vivo. This synergistic therapy was associated with the induction of apoptotic cell death with a decreased Bcl2 to Bax expression ratio and increased expression of cleaved caspase 3 and caspase 9 in the prostate cancer xenograft. These results indicate that cisplatin-chemotherapy in combination with targeting the MDM2/p53 axis is an attractive strategy to treat prostate cancer.