Abstract
We have investigated the effects of laminin, on the plasminogen-activator system of MCF-7 breast-carcinoma cells. MCF-7 cells were incubated on plastic or laminin-coated wells, and medium and cell lysate aliquots were assayed for tissue-type (tPA) and urokinase-type plasminogen activator (uPA) by a chromogenic assay in combination with anti-uPA antibodies. Cells cultured on laminin displayed a 5-fold increase in tPA activity and a 2-fold decrease in uPA activity relative to cells on plastic. These effects could be mimicked by laminin fragment P1 but not by collagen I or fibronectin. tPA activity of cells treated with estradiol (10 nM) was 3-fold higher, that of cells on laminin treated with estradiol was 15-fold higher, than that of control. Northern-blot analysis showed that tPA mRNA levels were up-regulated by estradiol and laminin, whereas PAI-1 mRNA levels were down-regulated by laminin and not affected by E2. Concomitant treatment with laminin and estradiol, decreased PAI-1 mRNA and increased tPA mRNA levels, accounting for the synergistic increase in tPA activity. Laminin exerted only a modest (approx. 2-fold) inhibitory effect on uPA mRNA levels. In the breast-carcinoma cell line MDA-MB-231, down-regulation of PAI-1 and ...Continue Reading
References
Oct 1, 1992·Current Opinion in Cell Biology·C H Damsky, Z Werb
Apr 1, 1991·International Journal of Cancer. Journal International Du Cancer·R Mira-y-LopezL Ossowski
Oct 1, 1990·The Journal of Cell Biology·R N TamuraV Quaranta
Feb 15, 1989·Journal of the National Cancer Institute·N Pourreau-SchneiderP M Martin
Jul 1, 1989·The Journal of Cell Biology·Y Takada, M E Hemler
May 1, 1988·In Vitro Cellular & Developmental Biology : Journal of the Tissue Culture Association·A NoelC M Lapiere
Jun 1, 1983·Cell·L Ossowski, E Reich
Jul 1, 1995·Clinical & Experimental Metastasis·M MaemuraR B Dickson
May 1, 1995·The Journal of Cell Biology·C H StreuliM J Bissell
May 1, 1995·The Journal of Steroid Biochemistry and Molecular Biology·M D DavisS C Brooks
Jan 1, 1993·Physiological Reviews·P Mignatti, D B Rifkin
Oct 11, 1996·The Journal of Biological Chemistry·C C YaoR H Kramer
Nov 1, 1996·Cell Adhesion and Communication·A ArcangeliM Olivotto
Nov 1, 1995·Trends in Cell Biology·A M Mercurio
Citations
Jul 4, 2006·Journal of Cellular Biochemistry·Sineenat SiriThomas T Chen
May 9, 2001·Biochimica Et Biophysica Acta·T IypeP R Sudhakaran
Oct 31, 2000·Microscopy Research and Technique·S Ghosh, M S Stack
Aug 24, 1999·Journal of Cellular Physiology·C Y SasakiA Passaniti
Sep 26, 2003·Journal of Dairy Science·S D K BerryR M Akers
Oct 19, 2001·The Journal of Biological Chemistry·J ChenS Huang
Feb 17, 2000·Clinica Chimica Acta; International Journal of Clinical Chemistry·J E KoblinskiB F Sloane