Downregulation of SS18-SSX1 expression in synovial sarcoma by small interfering RNA enhances the focal adhesion pathway and inhibits anchorage-independent growth in vitro and tumor growth in vivo

作者：Takenaka Satoshi; Naka Norifumi; Araki Nobuhito; Hashimoto Nobuyuki; Ueda Takafumi; Yoshioka Kiyoko; Yoshikawa Hideki; Itoh Kazuyuki^*

来源：International Journal of Oncology, 2010, 36(4): 823-831.

DOI：10.3892/ijo_00000559

• synovial sarcoma
• SS18-SSX
• morphology

Synovial sarcoma (SS) is an aggressive soft-tissue malignancy characterized by a unique t(X;18) translocation resulting in expression of SS18-SSX fusion protein. In order to investigate the biological function of this fusion protein and to develop a novel therapeutic option, we examined downregulation of SS18-SSX1 expression by small interfering RNA targeting SS18-SSX1 in three human SS cell lines. Microarray analysis comparing SS18-SSX1-silenced cells with control cells in three SS cell lines showed that SS18-SSX1 mainly affected the focal adhesion pathway. In accord with the array data, silencing of SS18-SSX1 enhances adhesion to the extracellular matrix through the induction of expression of myosin light-chain kinase. Furthermore, the silencing of SS18-SSX1 inhibits anchorage-independent growth in vitro and systemic delivery of siRNA against SS18-SSX1 using a nanoparticle system inhibited tumor growth in a nude mouse xenograft model. Our results demonstrate that siRNA targeting of SS18-SSX1 has therapeutic potential for the treatment of SS.

• 出版日期2010-4