Anti-tumor Effects Of A Dual Cancer-specific Oncolytic Adenovirus Carried Apoptin And HTERT Promoter On Breast Cancer In Vivo And Vitro

Breast cancer is the most common malignancy in women, has the biggest number of patients of malignant tumors, and the trend continues to increase. It is not only a serious threat to the health and quality of life of women, but also is a heavy burden to the global health system. Currently, surgery and chemotherapy are the primary methods of treatment of breast cancer, but these methods have their drawbacks, and it is difficult to cure patients. With the development of molecular biology, cell biology and virology, gene therapy has become a new means of cancer therapies, and adenoviral vector treatment showed a huge advantage.Constructed the recombinant adenovirus Ad-Apoptin-hTERTp-ElA (Ad-VT), and the control virus Ad-hTERTp-Ela (Ad-T), Ad-Apoptin (Ad-VP3) and Ad-mock by RAPAd. I adenoviral vector systems. The adenoviral vector was deleted the adenoviral genome backbone left arm inverted terminal repeat (ITR), packaging signals and early gene region 1 (E1) to minimize contamination of wild-type adenovirus during virus packaging process. The cytomegalovirus(CMV) promoter specific drived tumor suppressor gene Apoptin, hTERTp drived adenovirus type 5 early region 1A gene (early region 1A, E1a), such recombinant adenovirus Ad-Apoptin-hTERTp-Ela had the dual-specific anti-tumor effect of specific cytotoxicity and specific replication.Here, explored the inhibitory effects on MCF-7 cells and MCF-10A cells of recombinant adenovirus by MTS assay and crystal violet staining assay. The results showed that the recombinant adenovirus Ad-VT had obviously specific inhibition on human breast cancer MCF-7 cells, significantly enhanced inhibition compared with Ad-mock group(P<0.05), the inhibition had aging and dose effect relationship; and the recombinant adenovirus Ad-VT on normal human mammary cells MCF-10A did not have a significant inhibitory effect; We explored the inhibition way on MCF-7 cells of recombinant adenovirus by AO/EB, DAPI, Annexin V experiments, the results showed that the mainly inhibition on MCF-7 cells of recombinant adenovirus Ad-VT, Ad-T, Ad-VP3 was apoptosis, and the amount of apoptosis has aging and dose effect relationship; Explored the inhibitory effects of cells migration and invasion on MCF-7 cells of recombinant adenovirus by wound healing assay and the Transwell migration and invasion assay. The results showed that the migration and invasion ability of Ad-VT infected MCF-7 cells were greatly suppressed, the inhibition was stronger than Ad-mock (P<0.05), having a time-effect relationship; explored the anti-tumor effect in vivo of recombinant adenovirus by Establishing nude mice subcutaneous transplantation tumors model and vein metastasis tumors model of MCF-7 cells, and BABL/c mice subcutaneous transplantation tumors model and vein metastasis tumors model of 4T1 cells. The results showed that Ad-VT can significantly prolong the survival of nude mice models, inhibition BABL/c mice subcutaneous and intravenous tumor growth; The comprehensive results of the experiment showed that the dual-specific anti-tumor adenovirus Ad-VT were inhibited breast cancer in vitro and in vivo, having a value of clinical development in the treatment of breast cancer, and this study will provide a theoretical basis on clinical application of the dual-specific anti-tumor adenoviruses Ad-VT.