Faculty Opinions recommendation of Tumor angiogenesis in the absence of fibronectin or its cognate integrin receptors.

The relative roles of adhesion and locomotion in malignancy have yet to be clearly established. In a tumor, subpopulations of cells may be recognized according to their capacity to invade neighbouring tissue,or to enter the blood stream and metastasize. The mechanisms of adhesion and locomotion are themselves tightly linked to the cytoskeletal apparatus and cell surface topology, including expression of integrin receptors. In our studies on melanomas with Fluorescent Microscopy (FM) and Cell Sorter(FACS), we noticed that cells in cultures derived from metastases had more numerous actin bundles, then cells from primary foci. Following this track, we attempted to develop technology allowing to compare ultrastructure of these cells using correlative Transmission Electron Microscopy(TEM) and Low Voltage Scanning Electron Microscopy(LVSEM).

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Distribution of VLA-5 and VLA-4 fibronectin receptors in human monocytes demonstrated by immunofluorescence, immunocytochemistry, and autoradiography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147375 ◽

1993 ◽

Vol 51 ◽

pp. 306-307

Author(s):

Robert Williams ◽

Che-Hung Lee ◽

Sara E. Quella ◽

David M. Harlan ◽

Yuan-Hsu Kang

Keyword(s):

Present Report ◽

Matrix Proteins ◽

Extracellular Matrices ◽

Human Monocytes ◽

Integrin Receptors ◽

Morphological Evaluation ◽

The Matrix ◽

Specific Receptors ◽

Cytokine Stimulation ◽

Monocyte Adherence

Monocyte adherence to endothelial or extracellular matrices plays an important role in triggering monocyte activation in extravascular sites of infection, chronic inflammatory disorders, and tissue damage. Migration of monocytes in the tissues involves the response to a chemoattractant and movement by a series of attachments and detachments to the extracellular matrices which are regulated by expression and distribution of specific receptors for the matrix proteins such as fibronectin (FN). The VSAs (very late antigens or beta integrins), a subfamily of the transmembrane heterodimeric integrin receptors, have been thought to play a major role in monocyte adherence to the extracellular matrices and cells. In this subfamily, VLA-5 and VLA-4 are believed to be the most essential integrins mediating monocyte adherence to FN. In the present report, we have established and compared different procedures for morphological evaluation of the expression and distribution of the FN receptors on human monocytes in order to investigate their response to endotoxin or cytokine stimulation.

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Extracellular matrix: the gatekeeper of tumor angiogenesis

Biochemical Society Transactions ◽

10.1042/bst20190653 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1543-1555 ◽

Cited By ~ 10

Author(s):

Maurizio Mongiat ◽

Simone Buraschi ◽

Eva Andreuzzi ◽

Thomas Neill ◽

Renato V. Iozzo

Keyword(s):

Extracellular Matrix ◽

Tumor Angiogenesis ◽

Signaling Cascades ◽

Cancer Growth ◽

Cell Behavior ◽

Metastatic Progression ◽

Surface Receptors ◽

The Matrix ◽

Multiple Signaling

Abstract The extracellular matrix is a network of secreted macromolecules that provides a harmonious meshwork for the growth and homeostatic development of organisms. It conveys multiple signaling cascades affecting specific surface receptors that impact cell behavior. During cancer growth, this bioactive meshwork is remodeled and enriched in newly formed blood vessels, which provide nutrients and oxygen to the growing tumor cells. Remodeling of the tumor microenvironment leads to the formation of bioactive fragments that may have a distinct function from their parent molecules, and the balance among these factors directly influence cell viability and metastatic progression. Indeed, the matrix acts as a gatekeeper by regulating the access of cancer cells to nutrients. Here, we will critically evaluate the role of selected matrix constituents in regulating tumor angiogenesis and provide up-to-date information concerning their primary mechanisms of action.

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