In inflammation, cells interact with extracellular matrices or neighboring cells by a spatiotemporal intervention pattern of specific cell surface receptors and adhesion molecules. Resident cells of the injured tissue communicate with circulating effector cells by cytokines and direct cell-cell contact. These cytokines stimulate expression of the adhesion molecules ICAM-1, VCAM-1, and E- and P-selectin on endothelial cell surfaces and up regulate beta(2)-integrins and ICAM-1 on luminal leukocytes. White blood cells then adhere to the activated endothelial cells, migrate through the vessel wall, and penetrate areas of infection or tissue damage. The basis for a cellular immune response is formed by the interaction between T lymphocytes and antigen-presenting cells amplified by adhesion molecule LFA-1,2,3 to ICAM-1 binding. Proteins, glycoconjugates, and carbohydrate polymers are implicated in extracellular matrix formation and express multifunctionality as well as high versatility in both physiological and pathological processes, as for instance cytokine sequestration, basement membrane scaffolding, and tumor invasion and metastasis. The supramolecular architecture of basement membranes is largely dominated by self-assembly processes and specific heterophilic interactions between type IV collagen, perlecan, laminin, and entactin. These flexible thin mats are the strategic sites at which cells traverse this surface, subbase, and interfacial structure in inflammation and tumor invasion. Growth factors and other cytokines stored and cross-complexed at syndecan/perlecan low-affinity as well as PTKR-SF high-affinity binding sites interfere into these pathological scenarios. The three-step development of the invasive phenotype of cancer cells comprises cell attachment, local proteolysis, and cell migration. Adhesion is mediated by a contribution pattern of several classes of cell adhesion molecules such as vitronectin and laminin receptors amplified and ispersed over the entire cell surface. In addition, cytokine-inducible members of the immunoglobulin superfamily and the cell surface hyaluronan receptor facilitate the metastatic process in serving as tumor cell attachment sites to the vascular or lymphatic endothelium. Molecules of the cadherin family, however, suppress tumor invasion. Overexpression of E-cadherin in highly invasive clones resulted in a loss of invasive potency. Matrix metalloproteinases, constitutively overexpressed or induced by cytokines in tumor cell invasion, promote the extracellular matrix proteolysis. Growth factors such as EGF, TGF alpha, and PDGF up-regulate the transcription of interstitial collagenase and stromelysin. Moreover, the balance of active enzymes and their inhibitors (TIMPs) has shifted in favor of proteolysis. Tumor cell motility and metastatic spread are dominated by chemokinesis, chemotaxis, and haptotaxis. Matrix proteolysis and directional migration are prerequisites for intravasation, extravasation, and propagation into the target tissue. While the initial stages of metastasis encompass haptotactic migration over insoluble matrix proteins, chemotactic responses to partially degraded matrix components characterize the migratory phenotype later. Cell locomotion in eukaryotic cells resides in the cortical actin cytoskeleton which is interwoven with the cytoplasmic syndecan as well as the cell-and matrix-binding perlecan domains. Therefore, the actin-based cytoskeletal proteins a-actinin, filamin, and desmin were adsorbed as monomolecular layers to a hydrophobic silica surface in order to investigate the effect of Ca2+ ions by ellipsometry. Ca2+ ions in a concentration of 10(-4), 10(-3) and 2.52 mmol/l had no effect on the adsorbed amount, refractive index and molecular length of these individual intermediate filament proteins. Cross-linked filamin-desmin, however, reacted drastically upon calcium addition with a change in refractive index and molecular length. The 92.5 nm long filamin-desmin complex contracted by 2.5, 6.7, and 6.5 nm, respectively. The maximum shortening occurred already at 1 mu mol/l Ca2+. The Ca2+-dependent contraction of cross-linked filamin-desmin supports the contractile mechanisms in muscular tissues, and forms the basis for migration and motility in nonmuscular cells. These motional events are crucially involved in peripheral organ perfusion, inflammation, and tumor invasion and metastasis.