Cloning and expression of human HER2 protein on eukaryotic cell surface by transfection and transduction techniques for tumorogenesis in a mouse model

Abstract

Background and Objective: Breast cancer is the fifth common cause of death in the world and is considered as the leading cause of cancer related death among females. HER2 is a surface antigen which is overexpressed in 30% of breast cancer cases. The aim of this study was cloning of HER2 receptor gene in pCDNA3.1Hygro+ expression vector, expression of this protein in LL2 eukaryotic cell line and production of a breast cancer mouse model.


Materials and Methods: The construct expressing HER2 gene was synthesized by RNA extraction, HER2 gene amplification and its cloning into pCDNA3.1Hygro+  vector. The accuracy of cloning was approved by sequencing. In the next step, the construct was transfected into LL2 mouse cancer cells. To establish a stable cell line, transfected LL2 cells were cultured in hygromycine enriched medium for 1 month. The resultant cells had a very low growth rate. Having repeated the process three times, 106 cells were eventually produced. Injection of these cells into mice led to no tumor formation. Moreover, LL2 cells transducted by HER2 containing lenti-viruse were used collaterally to form tumors. Meanwhile, 106 transducted LL2 cells were injected subcutaneously into C57BL/6 mice. A tumor nodule was tangible 10 to 12 days post injection.       


Results: The HER2 gene was successfully amplified and cloned into pcDNA3.1Hygro+. Injection of transfected and transduced LL2 cells into mice demonstrated that only the LL2 cells transduced by the viral vector pLEX HER2 were able to express human HER2 gene stably.


Conclusion: By cloning and expression of HER2 on the LL2 cells, we could produce breast cancer model in mice expressing human HER2 on cells surface.

Keywords


1. Cancer-Its various types along with causes, symptoms, treatments and stages, in: cancer info guide. 2009. 2. Bookman MA, Darcy KM, Clarke-Pearson D, Boothby RA, Horowitz IR. Evaluation of monoclonal humanized anti-HER2 antibody, trastuzumab, in patients with recurrent or refractory ovarian or primary peritoneal carcinoma with overexpression of HER2: a phase II trial of the Gynecologic Oncology Group. Journal of Clinical Oncology 2003; 21(2): 283-90. 3. Tai W, Mahato R, Cheng K. The role of HER2 in cancer therapy and targeted drug delivery. Journal of Controlled Release 2010; 146(3): 264–75. 4. Olayioye MA. Update on HER-2 as a target for cancer therapy: intracellular signaling pathways of ErbB2/HER-2 and family members”. Breast Cancer Research 2001; 3(6): 385-9. 5. Garcia-Solis P, Yahia EM, Morales-Tlalpan V, Diaz-Munoz M. Screening of antiproliferative effect of aqueous extracts of plant foods consumed in Mexico on the breast cancer cell line MCF-7. International Journal of Food Sciences and Nutrition 2009; 60(6): 39-46. 6. Coussens L, Yang-Feng TL, Liao YC, Chen E, Gray A, McGrath J, Seeburg PH, Libermann TA, Schlessinger J, Francke U, et al. Tyrosine kinase receptor with extensive homology to EGF receptor shares chromosomal location with neu oncogene. Science 1985; 230(4730): 1132-9. 7. Ross JS, Slodkowska EA, Symmans WF, Pusztai L, Ravdin PM, HortobagyiGN. The HER-2 receptor and breast cancer: ten years of targeted anti-HER-2therapy and personalized medicine. Oncologist 2009; 14(4): 320-68. 8. Arteaga CL. ERBB receptors in cancer: signaling from the inside. Breast Cancer Research 2011; 13(2):304. 9. Yarden Y, Sliwkowski MX. Untangling the ErbB signalling network. Nature reviews. Molecular Cell Biology 2001; 2(2):127-37. 10. Heppner GH, Miller FR, Shekhar PM. Nontransgeni c models of breast cancer. Breast Cancer Research 2000; 2(5): 331-4. 11. Jonkers J, Derksen PW. Modeling metastatic breast cancer in mice. Journal of Mammary Gland Biology and Neoplasia 2007; 12(2-3): 191-203. 12. Xanthopoulos JM, Romano AE, Majumdar SK. Response of Mouse Breast Cancer Cells to Anastrozole, Tamoxifen, and the Combination. Journal of Biomedicine and Biotechnology 2005; 2005(1): 10-9. 13. Duś D, Budzyński W, Radzikowski C. LL2 cell line derived from transplantable murine Lewis lung carcinoma--maintenance in vitro and growth characteristics. Archivum Immunologiae et Therapiae Experimentalis (Warsz) 1985; 33(6):817-23. 14. Hoffman J, Schirner M, Menrad A. A highly sensitive model for quantification of in vivo tumor angiogenesis induced by alginate- encapsulated tumor cell. Cancer Research 1997; 57: 3847- 51. 15. Mcpherson MJ. PCR the basics from background to bench, Springer-Vergle Telos. 2003. 16. .Li R, Zheng H, Luo RC. Cloning and expression of the HER2 gene in MCF-7 cells. Di 1 jun yi da xue xue bao: Academic Journal of the First Medical College of PLA 2005; 25(10):1264-7. 17. O'Connor S, Li E, Majors BS, He L, Placone J, Baycin D, Betenbaugh MJ, Hristova K. Increased Expression of the Integral Membrane Protein ErbB2 in Chinese Hamster Ovary Cells Expressing the Anti-apoptotic Gene Bcl-xL. Protein Expression and Purification 2009; 67(1): 41–7. 18. Aigner A, Juhl H, Malerczyk C, Tkybusch A, Benz CC, Czubayko F. Expression of a truncated 100 kDa HER2 splice variant acts as an endogenous inhibitor of tumour cell proliferation. Oncogene 2001; 20, 2101-11. 19. Xu TF, Zhang WQ, Yu H, Li D. Construction of an eukaryotic plasmid encoding HER2 and screening of a cell line stably expressing clones. Xi bao yu fen zi mian yi xue za zhi: Chinese Journal of Cellular and Molecular Immunology 2009; 25(3): 226-8. 20. Dus D, Budzynski W, Radzikowski C. LL2 cell line derived from transplantable murine Lewis lung carcinoma-maintenance in vitro and growth characteristics. Archivum Immunologiae et Therapiae Experimentalis (Warsz) 1985; 33(6): 817-23. 21. Ramírez BS, Pestana ES, Hidalgo GG, García TH, Rodríguez RP, Ullrich A, Férnandez LE. Active antimetastatic immunotherapy in Lewis lung carcinoma with self EGFR extracellular domain protein in VSSP adjuvant. International Journal of Cancer 2006; 119(9): 2190-9. 22. Lu Y, Wei YQ, Tian L, Zhao X, Yang L, Hu B, Kan B, Wen YJ, Liu F, Deng HX, Li J,Mao YQ, Lei S, Huang MJ, Peng F, Jiang Y, Zhou H, Zhou LQ, Luo F. Immunogene therapy of tumors with vaccine based on xenogeneic epidermal growth factor receptor. Journal of Immunology 2003: 15; 170(6): 3162-70. 23. Ghaem Maghami M. Tumor inhibitory effects of immunization with nano phage particle displaying super mimotope of EGFR on pVIII in animal model. [Dissertation]. Tarbiat Modares University: 2010.