Gene Therapy for Prostate Cancer Radiosensitization Using Mutant Poly (ADP-Ribose) Polymerase.

摘要

During the first year of funding we have developed a recombinant plasmid (pPSA (e/p)-DBD/F) comprised of the coding region of the PARP-DBD linked to 5'-flanking sequences (1.3 kb upstream enhancer/ 0.6 kb minimal promoter) of the human PSA gene. The present study reports the development and characterization of LNCaP prostate carcinoma cell sublines expressing the human PARP-DBD protein in constitutive and androgen-inducible fashion. Tissue specificity of PARP-DBD expression in human tumor cells was confirmed using the PSA-positive (LNCaP) and PSA-negative (PC-3) prostate cancer cells and cells of non-prostate origin, Ewing's sarcoma (A4573 cells). We found that exposure of LNCaP cells stably transfected with pPSA (e/p)-DBD/F to synthetic androgen (R1881) resulted in dose-dependent stimulation of PARP-DBD expression at levels of mRNA and protein. Androgen-dependent fashion of PARP-DBD expression in LNCaP cells was further confirmed by in situ immunodetection of DBD-Flag fusion protein using fluorescence microscopy. Established cell lines provide a convenient experimental model to study effects of the PARP-DBD expression on prostate tumor responses to ionizing radiation and genotoxic drugs.