Influenza is an infectious disease that affects millions of people worldwide. Due to rapid antigenic drift, new influenza vaccines are formulated every year. Currently, trivalent inactivated viral vaccines are manufactured from chicken embryonated eggs and this production process requires extensive planning, laborious preparations, and reliable egg supplies. Although egg-based production has been used for more than 60 years, its inadequacies in response to a pandemic outbreak have prompted many studies to pursue the development of cell-based platforms. Several advantages of cell-based vaccines include rapid scale-up and the retention of viral antigenic properties. Among the tested continuous cell lines, Madin Darby Canine Kidney (MDCK) cells are one of the most promising cell substrates for influenza virus propagation. However, for commercially viable processes, cell lines are typically adapted or transformed to suspension cultures so they can be easily grown in industrial-scale bioreactors. In the current work, a fill-length gene encoding the sialyltransferase 7E enzyme was stably transfected in the MDCK cells to modify its cell-cell and cell-matrix adhesion properties. Subsequently, these genetically modified cells were tested in shake flask culture and were found to be able to survive and proliferate under anchorage-independent conditions. These cells were extensively characterized both in the effects of siat7e over-expression and its ability to support high-titer viral replication. Current vaccinating influenza viruses were tested in these modified cells and the results indicated that, under an optimized infection strategy, high titers of biologically active hemagglutinin that are comparable to the egg-based system can be obtained in bench-scale productions. Moreover, in signaling transduction analyses, it was observed that MDCK-siat7e cells exhibited many hallmarks of an epthelial-mesenchymal transition. This work demonstrates that suspension MDCK-siat7e cell line has promising applications not only in cell-based influenza vaccines but also in serving as a model cell line for metastasis research.