Objective: To construct eukaryotic expression vector of myc-tagged human HER2 and investigate its role in breast cancer cell proliferation and drug resistance.
Methods: Human HER2 gene was amplified by PCR and cloned into the pXJ-40-myc vector. The recombinant myc-HER2 was identified by enzyme digestion and sequencing, transfected into breast cancer cell line ZR75-1, and then was detected by Western blotting. Next, CCK8 assay was performed to investigate myc-Her2 transfected cell proliferation. Trastuzumab, anti-Her2 antibody, was added to determine the sensitivity of cells transfected with myc-Her2.
Results: Enzyme digestion and sequencing confirmed the myc-HER2 vector was constructed successfully. Western blotting showed the expression of myc-HER2 in the ZR75-1 cells. The result of cell growth curve showed that cells transfected with myc-her2 grew significantly faster than the control cells. Moreover, trastuzumab obviously suppressed the growth of ZR75-1 cells transfected with myc-HER2.
Conclusion: The myc-HER2 vector was successfully constructed which lays an experimental foundation for the study of HER2 drug resistance to trastuzumab.