tailieunhanh - Báo cáo khoa học: Inhibition of urokinase receptor gene expression and cell invasion by anti-uPAR DNAzymes in osteosarcoma cells

The urokinase-type plasminogen activator (uPA) receptor (uPAR) has been implicated in signal transduction and biological processes including cancer metastasis, angiogenesis, cell migration, and wound healing. It is a specific cell surface receptor for its ligand uPA, which catalyzes the formation of plasmin from plasminogen, thereby activating the proteolytic cascade that contributes to the breakdown of extracellular matrix, a key step in cancer metastasis. | iFEBS Journal Inhibition of urokinase receptor gene expression and cell invasion by anti-uPAR DNAzymes in osteosarcoma cells Charles E. de Bock Zhen Lin Takashi Itoh David Morris George Murrell and Yao Wang Orthopaedic Research Institute Department of Medicine St George Hospital University of New South Wales Sydney NSW Australia Keywords DNAzyme gene expression osteosarcoma cell invasion urokinase receptor Correspondence Y. Wang Orthopaedic Research Institute St George Hospital University of New South Wales Sydney NSW 2217 Australia Fax 61 2 9350 3967 Tel 61 2 9350 1422 E-mail These authors contributed equally to this work Received 11 October 2004 revised 28 February 2005 accepted 18 May 2005 doi The urokinase-type plasminogen activator uPA receptor uPAR has been implicated in signal transduction and biological processes including cancer metastasis angiogenesis cell migration and wound healing. It is a specific cell surface receptor for its ligand uPA which catalyzes the formation of plasmin from plasminogen thereby activating the proteolytic cascade that contributes to the breakdown of extracellular matrix a key step in cancer metastasis. We have synthesized three different DNA enzymes Dz372 Dz483 and Dz720 targeting uPAR mRNA at three separate purine A or G -pyrimidine U or C junctions. Two of these DNAzymes Dz483 and Dz720 cleaved uPAR transcript in vitro with high efficacy and specificity at a molar ratio uPAR to Dz as low as 1 . When analyzed over 2 h with a 200-fold molar excess of DNAzymes to uPAR transcript Dz720 and Dz483 were able to decrease uPAR transcript in vitro by w 93 and 84 respectively. They also showed an ability to cleave uPAR mRNA in the human osteosarcoma cell line Saos-2 after transfection. The DNA-zyme Dz720 decreased uPAR mRNA within 4 h of transfection and inhibited uPAR protein concentrations by 55 in Saos-2 cells. The decrease in uPAR mRNA and protein concentrations caused by Dz720