Tumor adhesion

As a sidebar, it should be noted that there is a domain on the fibronectin molecule which binds to the simple peptide RGD (arginine-glycine-aspartic acid) and this has been explored as a means of interfering with the tumor adhesion process using longer, more stable, polypeptide sequences and other analogues or derivatives (Humphries et al. 1987). 

An HA-rich matrix often correlates with a worse clinical prognosis. Metastatic potency is often enhanced in animal model systems when tumor cells are transfected with HAS genes. Inhibition of HAS gene expression with anti-HAS constructs reduces tumor adhesion and malignant potential [123,124]. 

Fig. 7.5 la,b. Recurrent tumor of the pelvic sidewall after hysterectomy. A T2w TSE image in transverse orientation. At the right pelvic sidewall, a solid, heterogeneous mass (arrows) is depicted that infiltrates the pelvic wall and extends to the iliac bone. TUmor adhesion to the sigmoid colon, b Tlw TSE image with FS transverse orientation 1 min after administration of Gd-DTPA. MRl depicts an enhancement on the postcontrast image and central necrosis... 

Interference with specific cell-cell and cell-matrix adhesion mechanisms is another rapidly advancing approach to therapeutically interfere with angiogenesis. Antagonistic antibodies (Vitaxin) to the integrin heterodimer av 33 have been shown to act on the blood vessels of tumors but not on the resting organ vasculature. Vitaxin demonstrated some promise in Phase II clinical trials. 

Van Roy, F., Mareel, M. (1992). Tumor invasion effects of cell adhesion and motility. Trends Cell Biol. 2, 163-169. 

Altered cell morphology Increased growth rate Increased saturation density Formation of multilayers Reduced adhesion to substratum Colony formation in soft agar Reduced serum requirement Altered growth factor requirement Tumor formation in athymic nude mice... 

Hyaluronic acid may be important in permitting tumor cells to migrate through the EGM. Tumor cells can induce fibroblasts to synthesize greatly increased amounts of this GAG, thereby perhaps facifitating their own spread. Some mmor cells have less heparan sulfate at their surfaces, and this may play a role in the lack of adhesiveness that these cells display. 

Booth V Keizer DW, Kamphuis MB et al (2002) The CXCR3 binding chemokine IP-IO/CXCLIO structure and receptor interactions. Biochemistry 41 10418-10425 Burns JM, Summers BC, Wang Y et al (2006) A novel chemokine receptor for SDF-1 and I-TAC involved in cell survival, cell adhesion, and tumor development. J Exp Med 203 2201-2213 Callebaut C, Krust B, Jacotot E et al (1993) T cell activation antigen, CD26, as a cofactor for entry of HIV in CD4+ cells. Science 262 2045-2050... 

Selective inhibition of tumor necrosis factor-induced vascular cell adhesion molecule-1 gene expression by a novel flavonoid. Lack of effect on trascriptional factor NF-kB Arteriosclerosis, Thrombosis and Vascular Biology 16, 1501-8. 

Bums JM, Summers BC, Wang Y, et al. A novel chemokine receptor for SDF-1 and I-TAC involved in cell survival, cell adhesion, and tumor development. J Exp Med 2006 203 2201-2213. 

A natural progression from using CA to model bacterial growth is to model tumor growth and the development of abnormal cells. There has been considerable work on this topic. Features such as cell mutation, adhesion, layered growth, and chemotaxis can readily be incorporated into a CA model.5 Deutsch and Dormann s book provides a useful introduction to this area.6... 

N5. Nierodjik, M. L., Plotkin, A., Kajuno, F., and Karpatkin, S., Thrombin stimulates tumor-platelet adhesion in vitro and metastasis in vivo. J. Clin. Invest. 87, 229-236 (1991). 

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