Intraperitoneal injection of a hairpin RNA-expressing plasmid targeting urokinase-type plasminogen activator (uPA) receptor and uPA retards angiogenesis and inhibits intracranial tumor growth in nude mice.
OBJECTIVE
The purpose of this study was to evaluate the therapeutic potential of using plasmid-expressed RNA interference (RNAi) targeting urokinase-type plasminogen activator (uPA) receptor (uPAR) and uPA to treat human glioma.


METHODS
In the present study, we have used plasmid-based RNAi to simultaneously down-regulate the expression of uPAR and uPA in SNB19 glioma cell lines and epidermal growth factor receptor (EGFR)--overexpressing 4910 human glioma xenografts in vitro and in vivo, and evaluate the i.p. route for RNAi-expressing plasmid administered to target intracranial glioma.


RESULTS
Plasmid-mediated RNAi targeting uPAR and uPA did not induce OAS1 expression as seen from reverse transcription-PCR analysis. In 4910 EGFR-overexpressing cells, down-regulation of uPAR and uPA induced the down-regulation of EGFR and vascular endothelial growth factor and inhibited angiogenesis in both in vitro and in vivo angiogenic assays. In addition, invasion and migration were inhibited as indicated by in vitro spheroid cell migration, Matrigel invasion, and spheroid invasion assays. We did not observe OAS1 expression in mice with preestablished intracranial tumors, which were given i.p. injections of plasmid-expressing small interfering RNA--targeting uPAR and uPA. Furthermore, the small interfering RNA plasmid targeting uPAR and uPA caused regression of preestablished intracranial tumors when compared with the control mice.


CONCLUSIONS
In conclusion, the plasmid-expressed RNAi targeting uPAR and uPA via the i.p. route has potential clinical applications for the treatment of glioma.
Gondi
Christopher S
CS
Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine at Peoria, Peoria, Illinois 61605, USA.
Lakka
Sajani S
SS
Dinh
Dzung H
DH
Olivero
William C
WC
Gujrati
Meena
M
Rao
Jasti S
JS
D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology* / Q000517:prevention & control; D045744:Cell Line, Tumor; D005910:Glioma / Q000517:prevention & control; D006801:Humans; D007274:Injections, Intraperitoneal; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D010957:Plasmids; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics*; D055293:Receptors, Urokinase Plasminogen Activator; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014183:Transplantation, Heterologous; D014568:Urokinase-Type Plasminogen Activator / Q000235:genetics*
D020533:Angiogenesis Inhibitors; C524898:PLAUR protein, human; C524899:Plaur protein, mouse; D034741:RNA, Small Interfering; D011956:Receptors, Cell Surface; D055293:Receptors, Urokinase Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator