Antisense inhibition of urokinase: Effect on malignancy in a human osteosarcoma cell line
Expression of urokinase‐type plasminogen activator (u‐PA) strongly correlates with a malignant tumor cell phenotype. In the multistep process of metastasis, different cellular functions are influenced by urokinase. The enzyme is known to be effective via both proteolytical and signal transduction me...
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Published in | International journal of cancer Vol. 77; no. 1; pp. 153 - 160 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
New York
Wiley Subscription Services, Inc., A Wiley Company
03.07.1998
Wiley-Liss |
Subjects | |
Online Access | Get full text |
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Summary: | Expression of urokinase‐type plasminogen activator (u‐PA) strongly correlates with a malignant tumor cell phenotype. In the multistep process of metastasis, different cellular functions are influenced by urokinase. The enzyme is known to be effective via both proteolytical and signal transduction mechanisms. In the present study, the osteosarcoma cell line MNNG/HOS was transfected with a vector capable of expressing an antisense transcript, complementary to 1,021 bases of the 3′ end of u‐PA cDNA. This construct was most effective in reducing u‐PA expression in previous experiments. Stably transfected antisense (as) cell lines were characterized and compared with the parental MNNG/HOS. Antisense transfection of MNNG/HOS gave the following results: (1) stable incorporation of the construct into the genome of as‐clones, as detected by Southern blot analysis; (2) decreased mRNA level of u‐PA, as detected by Northern blot analysis; (3) approximately 50% reduced enzyme expression in cell culture medium and cell homogenate; and (4) unchanged cellular proliferation activity and u‐PAR expression. In further functional analysis, as‐clones showed (1) significantly reduced invasion and motility in modified Transwell chambers (random migration and chemotaxis with collagen I as a chemoattractant); (2) significantly reduced adhesion on matrices of collagen I and vitronectin; (3) unchanged adhesion properties on Matrigel matrix; and (4) reduced metastatic potential to lungs and especially liver in chick embryos after i.v. infection into chorioallantoic membrane veins. Our data show that in MNNG/HOS urokinase influences cellular malignancy by promoting migration and selective adhesion. These specific functions were notable in addition to the effects on invasion and basement membrane degradation. Int. J. Cancer 77:153–160, 1998.© 1998 Wiley‐Liss, Inc. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0020-7136 1097-0215 |
DOI: | 10.1002/(SICI)1097-0215(19980703)77:1<153::AID-IJC23>3.0.CO;2-E |