Recent advances in research on fibronectin and other cell attachment proteins

Abstract

Fibronectin and other cell attachment proteins provide molecular models for beginning to unravel the complex interactions of the cell surface with the extracellular matrix. This area has been reviewed in considerable detail previously [I-lo]. Our brief review will therefore be selective rather than comprehensive, and it will focus on some recent generalizations about this class of proteins, as well as on recent advances in the molecular analysis of the functions of these proteins and their receptors. We shall also present various popular or provocative hypotheses and speculations about future work in the field. CLASSES AND SPECIFICITY OF ATTACHMENT PROTEINS of 1)An emerging generalization about this class of proteins is that they are composed separable functional regions, each specialized for specific binding activities (Fig. . Each appears to have one or more regions essential for binding to the cell surface. Fibronectin (Fig. 2) interacts with the fibroblast cell surface primarily through a region termed the cell-binding or cell-recognition site; recent molecular analysis of the function of this site will be discussed below. Although this site appears to be required for cell interactions with fibronectin [ 11,121, interactions at a heparin-binding domain may provide substantial strengthening of this interaction [ 131. In addition, neuronal cells may be capable of interacting with a heparin-binding domain elsewhere in the molecule in the process of axonal elongation; fibronectin-independent interactions with extracellular materials such as heparan-sulfate-containing molecules appear to be important in some aspects of this process [ 14,151.

The role of colon fibroblasts in malignant large bowel obstruction – an experimental in vitro model

“…The extracellular matrix is composed largely of collagen, and cell-collagen binding is thought to be mediated by glycoprotein attachment molecules and proteoglycans (Yamada et al, 1985). Human colon carcinomas in organ culture have been found to synthesise proteoglycans and their production in the neoplastic colon appears to be localised to the stromal cell compartment rather than the epithelial compartment lozzo & Wight, 1982).…”

“…Although the mechanisms involved in fibroblast-collagen attachments have not been fully elucidated they are thought to involve non-collagenous glycoproteins and proteoglycans (Yamada et al, 1985). In colon cancer, tumour cells cultured in vitro have been shown not only to synthesise proteoglycans themselves but also to induce proteoglycan synthesis by normal colon fibroblasts (Iozzo, 1984(Iozzo, , 1985.…”

“…One possibility is that malignant large bowel obstruction is related to tumour fibrosis since the latter has also been associated with a worse prognosis in rectal cancer (Jass et al, 1986). Although the mechanism of the fibrotic response observed in colorectal cancer remains unclear it is likely to involve not only deposition of new matrix, but also re-organisation of existing stroma.The extracellular matrix is composed largely of collagen, and cell-collagen binding is thought to be mediated by glycoprotein attachment molecules and proteoglycans (Yamada et al, 1985). Human colon carcinomas in organ culture have been found to synthesise proteoglycans and their production in the neoplastic colon appears to be localised to the stromal cell compartment rather than the epithelial compartment lozzo & Wight, 1982).…”

Cellular fibronectin concentration in the plasma of patients with malignant and benign diseases: a comparison with CA 19-9 and CEA

“…FNs have a role in various biological phenomena, such as tissue organization, cell adhesion, mobility and differentiation, as well as in tumour invasion and metastasis (Yamada et al, 1985;Humphries et al, 1988;Coachman et al, 1990;Schwarzbauer, 1991). In many studies, total FN in plasma and other body fluids has been evaluated as a marker for cancer or other diseases (Parsons et al, 1979a,b;Webb and Linn, 1980;Stathakis et al, 1981;Choate and Mosher, 1983;Siri et al, 1984;Boccardo et al, 1986;Ruelland et al, 1988; Katayama et al, 1991).…”

Mast cell modulation of tumour cell proliferation in rat mammary adenocarcinoma 13762NF

“…Tumour cell interactions with the interstitial stroma or specific host cells may be of prime importance in determining invasive and metastatic behaviour (Yamada et al, 1985;Woolley, 1984;Dabbous et al, 1986a). Stromal changes including extensive collagen degradation have been observed, and there is substantial evidence for the release of collagenolytic enzymes by invasive tumour cells (Dabbous et al, 1983;1986a and b;Liotta et al, 1982;Woolley 1982).…”