Anti-tumor effects of a recombinant anti-prostate specific membrane antigen immunotoxin against prostate cancer cells. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Meng, Ping; Dong, Qing-chuan; Tan, Guang-guo; Wen, Wei-hong; Wang, He; Zhang, Geng; Wang, Yan-zhu; Jing, Yu-ming; Wang, Chen; Qin, Wei-jun; Yuan, Jian-lin
• Is Part Of: BMC urology. Volume 17:Issue 1(2017)
• Page Start: 1
• Page End: 7
• Publication Date: 2017-12
• Subjects: Gene therapy -- Prostate cancer -- Prostate-specific membrane antigen -- Recombinant protein -- Apoptosis; Urology -- Periodicals; 616.6005
• DOI: 10.1186/s12894-017-0203-9
• Languages: English
• ISSNs: 1471-2490

Abstract

Abstract Background To evaluate anti-prostate cancer effects of a chimeric tumor-targeted killer protein. Methods We established a novel fusion gene, immunocasp-3, composed of NH2-terminal leader sequence fused with an anti-prostate-specific membrane antigen (PSMA) antibody (J591), the furin cleavage sequences of diphtheria toxin (Fdt), and the reverse coding sequences of the large and small subunits of caspase-3 (revcaspase-3). The expressing level of the immunocasp-3 gene was evaluated by using the reverse transcription-PCR (RT-PCR) and western blot analysis. Cell viability assay and cytotoxicity assay were used to evaluate its anti-tumor effects in vitro. Apoptosis was confirmed by electron microscopy and Annexin V-FITC staining. The antitumor effects of immunocasp-3 were assessed in nude mice xenograft models containing PSMA-overexpressing LNCaP cells. Results This study shows that the immunocasp-3 proteins selectively recognized and induced apoptotic death in PSMA-overexpressing LNCaP cellsin vitro, where apoptotic cells were present in 15.3% of the cells transfected with the immunocasp-3 expression vector at 48 h after the transfection, in contrast to 5.5% in the control cells. Moreover, LNCaP cells were significantly killed under the condition of the co-culture of the immunocasp-3-secreting Jurkat cells and more than 50% of the LNCaP cells died when the two cell lines were co-cultured within 5 days. In addition, The expression of immunocasp-3 also significantly suppressed tumor growth and greatly prolonged the animal survival ratein vivo . Conclusion A novel fusion gene, immunocasp-3, may represent a viable approach to treating PSMA-positive prostate cancer.