Effect of NET-1 siRNA conjugated sub-micron bubble complex combined with low-frequency ultrasound exposure in gene transfection

// Bolin Wu 1 , Xitian Liang 1 , Hui Jing 1 , Xue Han 1 , Yixin Sun 1 , Cunli Guo 1 , Ying Liu 1 and Wen Cheng 1 1 Department of Ultrasound, Harbin Medical University Cancer Hospital, Nangang, Harbin, 150081, Heilongjiang Province, China Correspondence to: Wen Cheng, email: chengwen69@yahoo.com Keywords: sub-micron bubbles; low-frequency ultrasound; NET-1 siRNA; hepatocellular carcinoma; gene silencing Received: April 21, 2017      Accepted: December 14, 2017      Published: December 23, 2017 ABSTRACT The present study evaluated the effect of NET-1 siRNA-conjugated sub-micron bubble (SMB) complexes combined with low-frequency ultrasound exposure in gene transfection. The NET-1 gene was highly expressed level in SMMC-7721 human hepatocellular carcinoma cell line. The cells were divided into seven groups and treated with different conditions. The groups with or without low-frequency ultrasound exposure, groups of adherent cells, and suspension cells were separated. The NET-1 siRNA-conjugated SMB complexes were made in the laboratory and tested by Zetasizer Nano ZS90 analyzer. Flow cytometry was used to estimate the transfection efficiency and cellular apoptosis. Western blot and quantitative real-time polymerase chain reaction (qPCR) were used for the estimation of the protein and mRNA expressions, respectively. Transwell analysis determined the migration and invasion capacities of the tumor cells. The results did not show any difference in the transfection efficiency between adherent and suspension cells. However, the NET-1 siRNA-SMB complexes combined with low-frequency ultrasound exposure could enhance the gene transfection effectively. In summary, the NET-1 siRNA-SMB complexes appeared to be promising gene vehicle.