Role of the β1-integrin subunit in the adhesion, extravasation and migration of T24 human bladder carcinoma cells

Abstract

The abilities of tumor cells to extravasate from the blood vessel system and to migrate through the connective tissue are prerequisites in metastasis formation. Both processes are chiefly mediated by integrins, which mediate both cell-cell and cell-matrix interactions. We investigated the role of integrin subunits in the adhesion, extravasation and migration of the highly invasive human bladder carcinoma cell line T24. Here we show that inhibition of the beta(1)-integrin subunit using the specific beta(1)-integrin blocking antibody 4B4 significantly reduces the adhesion to HUVEC and transmigratory activity of T24 cells. The blockade of the beta(1)-integrin subunit also resulted in a significantly reduced locomotory activity of T24 cells. A detailed cell migration analysis on a single cell level revealed that blockade of the beta(1)-integrin subunit leads to an altered migration pattern of single cells but does not influence migration per se. Migration parameters such as time active, velocity and distance migrated were significantly reduced as compared to untreated control cells. Our observations strongly suggest a central role for the beta(1)-integrin subunit in forming the cell-cell and cell-matrix bonds necessary for adhesion, extravasation and migration.

Alteration in the gene expression pattern of primary monocytes after adhesion to endothelial cells

“…HUVECs were isolated from freshly dissected umbilical cords as described previously (41). HUVECs were maintained in endothelial cell growth medium ECGM (Promocell, Heidelberg, Germany) containing 2% FCS, 0.4% endothelial cell growth supplement/heparin, 0.1 ng/ml epidermal growth factor, 1 ng/ml basic fibroblast growth factor, and 1 g/ml hydrocortisone (SupplementMix; Promocell).…”

DNAzymes to mouse β1 integrin mRNA in vivo: targeting the tumor vasculature and retarding cancer growth

“…The first strand cDNA was synthesized according to the manufacturer's instruction using (dT) 20 primer. Then, b1 mRNA was determined by relative quantitative RT-PCR using glyceraldehyde-3-phosphate dehydrogenase mRNA (GAPDH mRNA) as an internal standard.…”

“…Regulation of integrin expression at the level of protein synthesis, either by synthetic oligodeoxynucleotides 15,16 or the viral-mediated infection of endothelial cells to express the antisense RNA endogenously, 18 has been suggested as an alternative method to inhibit angiogenesis in vivo. In addition to avb3, the collagen receptors a1b1 and a2b1 19 and other b1 integrin receptors 20 have been shown to play important roles in angiogenesis and tumor growth. 21 Integrin receptors play a primary role in the motility of cancer cells.…”

Analysis of Cell Migration within a Three-dimensional Collagen Matrix

“…Cell migration is a complex, not yet fully understood process that is directed by the interplay of several signal transduction pathways initiated by various ligand (e.g., cytokines, chemokines, growth factors, hormones, extracellular matrix components) receptor (e.g., receptor tyrosine kinases, chemokine receptors, integrins) interactions 5 ultimately causing the reorganization of the actin cytoskeleton concomitant with de-and reassembly of focal adhesion complexes and integrin-mediated signaling 6 .…”

“…Conjointly, due to time-lapse video microscopy real cell migration is measured allowing the determination of several migration parameters as well as their alterations in response to pro-migratory factors or inhibitors. Various cell types could be analyzed using this technique, including lymphocytes and leukocytes 11,20 , hematopoietic stem/ progenitor cells [21][22][23][24] , and tumor cells 5,[25][26][27][28][29] . In addition to single cells also cell clusters or spheroids could be embedded within the collagen matrix concomitant with analysis of the emigration of single cells from the cell cluster/ spheroid into the collagen lattice 30,31 .…”