BACKGROUND: Reports show that ultrasound-targeted microbubble destruction (UTMD) is a promising method of gene therapy, and metadherin (MTDH) is related to the development of breast cancer. Thus, we investigated the role of MTDH in breast cancer and compared the effect of suppressing MTDH by shRNA using liposome, UTMD, or the combination of these 2 methods.

MATERIAL AND METHODS: Graphing of survival curves of MTDH was analyzed by bioinformatics. UTMD was conducted using an ultrasonic therapeutic apparatus. Cell counting kit-8 (CCK-8) assay was used to measure cell viability. Migration and invasion rates were measured by wound healing test and Transwell invasion assay, respectively. The expression of MTDH, E-cadherin, metastasis-associated protein-1 (MTA-1), matrix metalloproteinase (MMP)-2, and MMP-9 were measured by Western blot and qPCR.

RESULTS: The prognosis of breast cancer can be decreased by the high expression of MTDH, and elevated expression of MTDH was discovered in MCF-7, MCF-10A, and T47D cell lines. UTMD combined with liposome is most efficient in transfecting shRNA, clearly suppressing the expression of MTDH and thereby decreasing cell viability, migration, invasion rate, and epithelial- mesenchymal transition (EMT) processes in the MCF-7 cell line.

CONCLUSIONS: UTMD combined with liposome could be used as a more efficient way to transfect shRNA into cells to suppress the expression of MTDH and thus lead to the downregulation of proliferation, migration, and EMT processes of the MCF-7 cell line, showing the potential for use in gene therapy.

Keywords: 14-3-3 Proteins, Transfection, Breast Neoplasms, Cell Adhesion Molecules, Down-Regulation, Liposomes, Membrane Proteins, Microbubbles, RNA, Small Interfering, RNA-Binding Proteins, Ultrasonics, Wound Healing