Human breast adenocarcinoma cell lines promote angiogenesis by providing cells with uPA-PAI-1 and by enhancing their expression.

During angiogenesis, endothelial cells use uPA and PAI-1 to migrate and degrade the basement membrane surrounding capillary blood vessels. Invasive tumor cells produce a large amount of uPA that could bind uPAR present at the endothelial cell surface to facilitate their invasion. To verify this hypothesis, endothelial cells were incubated with conditioned medium (CM) from two breast cancer cell lines (MCF7 and MDA MB 231 cells).

Induction of SPARC by VEGF in human vascular endothelial cells.

SPARC/osteonectin/BM-40 is a matricellular protein that is thought to be involved in angiogenesis and endothelial barrier function. Previously, we have detected high levels of SPARC expression in endothelial cells (ECs) adjacent to carcinomas of kidney and tongue. Although SPARC-derived peptide showed an angiogenic effect, intact SPARC itself inhibited the mitogenic activity of vascular endothelial growth factor (VEGF) for ECs by the inhibiting phosphorylation of flt-1 (VEGF receptor 1) and subsequent ERK activation.

Down-regulation of vascular endothelial growth factor by tissue inhibitor of metalloproteinase-2: effect on in vivo mammary tumor growth and angiogenesis.

The tissue inhibitor of metalloproteinases-2 (TIMP-2) has at least two independent functions, i.e., regulation of matrix metalloproteinases and growth promoting activity.

Induction of endothelial cell apoptosis by solid tumor cells.

The mechanisms by which tumor cells extravasate to form metastasis remain controversial. Previous studies performed in vivo and in vitro demonstrate that the contact between tumor cells and the vascular wall impairs endothelium integrity. Here, we investigated the effect of breast adenocarcinoma MCF-7 cells on the apoptosis of human umbilical vein endothelial cells (HUVEC).

Inhibition of stromal matrix metalloproteases: effects on breast-tumor promotion by fibroblasts.

Co-injection of fibroblasts with human epithelial breast-tumor MCF7 cells in the presence of Matrigel enhances tumor growth in nude mice. While most of the matrix metalloproteinases (MMPs) have been shown to be produced by stromal cells, tumor cells such as MCF7 cells are unable to produce MMPs. We therefore, hypothesized that the tumor-promoting effect of fibroblasts could be related to their production of MMPs.

Endothelial cell intracellular Ca2+ concentration is increased upon breast tumor cell contact and mediates tumor cell transendothelial migration.

Tumor cell extravasation is a determinant step in the process of hematogenous metastasis. The signal transduction pathways involved in the interactions between tumor cells and the vascular endothelium during transendothelial migration are still undefined. In the present study, we have investigated the influence of human breast adenocarcinoma cells (MCF7) on human umbilical vein endothelial cell (HUVEC) intracellular Ca2+ concentration ([Ca2+]i).

Alteration of interendothelial adherens junctions following tumor cell-endothelial cell interaction in vitro.

The integrity of the vascular endothelium is mainly dependent upon the organization of interendothelial adherens junctions (AJ). These junctions are formed by the homotypic interaction of a transmembrane protein, vascular endothelial cadherin (VE-cadherin), which is complexed to an intracellular protein network including alpha-, beta-, and gamma-catenin. Additional proteins such as vinculin and alpha-actinin have been suggested to link the VE-cadherin/catenin complex to the actin-based cytoskeleton.

Emerging roles for proteinases in cancer.

Metalloproteinases and serine proteinases have been associated with tumor invasion and formation of metastasis which represent the major obstacles to cancer cure. The contribution of proteinases in these processes was initially thought to be the destruction of extracellular matrices. However, recent evidence suggests that they mainly affect tumor growth rather than invasion.

Wavelet analysis of olfactory nerve response to stimulus.

Multiunit electrophysiological activity recorded by gross electrodes from the olfactory nerve was analyzed by wavelet decomposition, a relatively new method of signal processing. The analysis was run on data from the unstimulated olfactory system as well as on data evoked in response to six different odorant stimuli. Like Fourier analysis, wavelet analysis provides a spectral decomposition of the signal.

Plasma membrane-dependent activation of gelatinase A in human vascular endothelial cells.

The initiation of the angiogenic process requires a locally confined and time-limited proteolysis of the basement membrane (BM) components at the site of new vessel sprout. Gelatinase A, a member of the matrix metalloproteinase family, degrades BM type IV collagen and is involved in the BM breakdown by migrating tumor cells and endothelial cells (EC). Gelatinase A is synthesized as latent proenzyme and must be activated in order to express its proteolytic activity.

Thrombospondin modulates human breast adenocarcinoma cell adhesion to human vascular endothelial cells.

Thrombospondin (TSP), a M(r) 450,000 cytoadhesive glycoprotein, has been shown to potentiate tumor cell metastasis in mice by a mechanism that involves the hemostatic system of the host. In this study, the potential involvement of TSP in the interaction of human mammary adenocarcinoma MCF-7 cells with human umbilical vein endothelial cells (HUVECs) in culture was investigated. Using an ELISA, preconfluent HUVECs synthesized 100-fold more TSP than did MCF-7 cells during 24 h of culture (20 versus 0.

Coordinate enhancement of gelatinase A mRNA and activity levels in human fibroblasts in response to breast-adenocarcinoma cells.

Gelatinases/type-IV collagenases are metalloproteinases involved in some carcinoma invasion and metastatic processes. The exact cellular source of the 72-kDa gelatinase A is controversial. We have analyzed the expression of mRNA coding for gelatinase A in vivo by in situ hybridization on breast-cancer tissues.

[Coracoid process abutment according to Latarjet versus the Bankart operation. A comparative study of the results in 50 cases].

The authors have analyzed the postoperative results in 50 patients of two surgical techniques used for the treatment of anterior recurrent dislocation of the shoulder. The study only concerns "virgin" shoulders having formally presented numerous anterior recurrent dislocations treated by the Bankart procedure or the Bristow-Latarjet operation. This work consists of a clinical evaluation with objective and subjective results on one hand, and a radiological evaluation on the other hand.

[Dislocation of the tibialis posterior tendon].

The authors report a case of traumatic dislocation of the tibialis posterior tendon on the medial malleolus. They describe the treatment applied and made a review of the literature about this rare pathology.

Rat chromosome 5 (q22-23) contains elements that control cell morphology and interactions with the extracellular matrix: a study of normal fibroblast x malignant hepatoma cell hybrids.

Cell interactions with the extracellular matrix are consistently modified in neoplasia. Malignant transformation has been correlated with modifications in the synthesis and distribution of matrix components and with alterations of cell adhesive properties to these components. A particular class of genes, able to suppress the transformed phenotype in normal cells, may be involved in those phenotypic changes.

Malignant cell attachment to endothelium of ex vivo perfused human umbilical vein. Modulation by platelets, plasma and fibronectin.

The success of blood-born metastatic spread depends upon a key event: the tumor cell arrest and attachment to the host organ vasculature. In the present study, we have investigated interactions between several normal and cancer cell lines and vascular endothelium in a model of ex vivo perfusion of human umbilical vein. In this system, hydrodynamic parameters are monitored and endothelial cells are kept in their original environment known to modulate their phenotype.

[Multicenter Belgian study of the results of total arthroplasty for persistent congenital hip dislocation].

The SO.B.C.

[The Herbert screw in the treatment of fractures and pseudarthrosis of the carpal scaphoid. Review of 25 cases].

The Authors have reviewed the charts of 25 patients with scaphoid lesions treated with the Herbert screw and this study reports their personal experience. Between September 1983 and December 1986, 4 fresh fractures, 5 delayed unions and 16 pseudarthrosis were treated by means of this osteosynthesis procedure. The mean follow-up was 22 months.