title: Combined treatment of PC-3 cells with ultrasound and microbubbles suppresses invasion and migration.
abstract: The aim of the present study was to investigate whether ultrasound treatment combined with microbubbles inhibits cell invasion and migration in androgen-independent prostate cancer (PCa) cells and to identify the probable mechanism. Ultrasound was used in continuous wave mode at a frequency of 21 kHz and with a spatial-average temporal-average intensity of 46 mW/cm2. Ultrasound combined with microbubbles (200 μl; SonoVue) was administered to androgen-independent human PCa PC-3 cells for 30 sec. The PC-3 cells were divided into three groups: The control group, the ultrasound group (US) and the ultrasound combined with microbubbles group (US + MB). Following treatment for 12, 24, 48 and 72 h, cell counting kit-8 was used to assess cell viability. Cell invasion and migration was measured 12 h after treatment using Transwell migration assays. Quantitative polymerase chain reaction and western blot analysis were used to evaluate the expression of the migration-associated proteins, matrix metalloproteinase (MMP)-2 and MMP-9. Cell reproduction levels in the US and US + MB groups were significantly suppressed when compared with the control group (P<0.01) following 24 h of treatment and this suppression was significantly higher in the US + MB group than in the US group (P<0.01). However, no significant differences in cell reproduction levels between the three groups were identified at 12 h (P>0.05). Ultrasound combined with microbubbles significantly suppressed the level of invasion and migration in the PC-3 cells compared with the control group (190.83±14.63 vs. 509.67±18.62, P<0.01; and 86.67±10.60 vs. 271.33±65.14; P<0.01, respectively). Furthermore, combined treatment with ultrasound and microbubbles suppressed the expression of MMP-2 and MMP-9. In conclusion, it was found that ultrasound combined with microbubbles suppressed invasion and migration in human PCa PC-3 cells via downregulation of MMP-2 and MMP-9.
authors.affiliation: Department of Ultrasound in Medicine, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Institute of Ultrasound in Medicine, Shanghai 200233, P.R. China.
authors.forename: Cong
authors.initials: C
authors.lastname: Wei
authors.affiliation: Department of Ultrasound in Medicine, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Institute of Ultrasound in Medicine, Shanghai 200233, P.R. China.
authors.forename: Wen-Kun
authors.initials: WK
authors.lastname: Bai
authors.affiliation: Department of Ultrasound in Medicine, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Institute of Ultrasound in Medicine, Shanghai 200233, P.R. China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Ultrasound in Medicine, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Institute of Ultrasound in Medicine, Shanghai 200233, P.R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Hu
keywords: invasion; low-frequency ultrasound; matrix metalloproteinase-2; matrix metalloproteinase-9; microbubble; migration