Cell growth and differentiation

Aon M A and Cortassa S 1995 Cell growth and differentiation from the perspeotive of dynamioal organization of oellular and suboellular prooesses Prog. Biophys. Molec. Biol. 64 55-79... 

Figure 13.24 Six subfamilies of receptor tyrosine kinases involved in cell growth and differentiation. Only one or two members of each subfamily are indicated. Note that the tyrosine kinase domain is interrupted by a "kinase insert region" in some of the subfamilies. The functional significance of the cysteine-rich and immunoglobulin-like domains is unknown.

PKC isozymes are involved in a wide array of diverse cellular functions [5]. Most isozymes (e.g., PKC (3) are involved in proliferative responses, and hyperactivation with phorbol esters most typically results in cell growth and differentiation. However, isozymes can have opposing functions. PKC 8 is well-characterized as an apoptotic kinase, whereas the closely related PKC e is antiapoptotic. PKC also plays a key role in learning and memory. 

Of course, the critical importance of Ras and most other small G proteins in cell growth and differentiation is highlighted by the consideration, stated above, that several forms of these proteins are proto-oncogenes (see also... 

The Ras signal transduction cascade is of extreme physiological importance. It is central to the regulation of cell growth and differentiation, and false regulation of this signal pathway can be one of the critical steps leading to cell transformation.151 A... 

Horseradish peroxidase (HRP) is an extracellular plant enzyme that acts in regulation of cell growth and differentiation, polymerization of cell wall components, and the oxidation of secondary metabolites essential for important pathogenic defense reactions. Because of these essential functions, and also because of its stability and ready availability, HRP has attracted considerable attention.13 It has been involved in a number of applications, such as diagnostic assays,14 biosensors,15 bioremediation,16 polymer synthesis,17 and other biotechnological processes.18 More applications in which HRP catalysis is translated into an electrochemical signal are likely to be developed in the near future. 

This cell line was recently established by Mohan et al. [64], Intensive testing of this cell line regarding its suitability for pharmaceutical purposes has not been performed yet. The cell line is highly interesting, however, because of its controlled cell growth and differentiation capabilities. An integrated DNA section allows cell growth to be switched on or off. Therefore, further examination of this cell line should be of major interest and importance for various pharmaceutical researches. 

The progress in understanding TGF-fl signaling roles and mechanisms resulted in applications in medicine and biotechnology, including artificial intervention into stem cell growth and differentiation, or development of new generations of pharmaceutical compositions for tissue restoration and treatment of such diseases as cancer, cardiovascular or renal dysfunctions, and immune disorders. 

A wide variety of other biochemical effects has been reported to be associated with treatment of cells with vinblastine, vincristine, and related compounds (S). These effects include inhibition of the biosynthesis of proteins and nucleic acids and of aspects of lipid metabolism it is not clear whether such effects contribute to the therapeutic or toxic actions of vincristine and vinblastine. Vinblastine and vincristine inhibit protein kinase C, an enzyme system that modulates cell growth and differentiation (9). The pharmacological significance of such inhibition has not been established, however, and it must be emphasized that the concentrations of the drugs required to inhibit protein kinase C are several orders of magnitude higher than those required to alter tubulin polymerization phenomena (10). 

Filipp, D., Alzadeh-Khiavi, K., Richardson, C., Palma, A., Paredes, N., Takeuchi, O., Akira, S., and Julius, M. (2001). Soluble CD14 enriched in colostrum and milk induces B cell growth and differentiation. Proc. Natl. Acad. Sci. USA 98, 603-608. 

Protein kinases can be classified according to the amino acid residue that is phosphorylated in the cellular process. Consequently, there are tyrosine-specific kinases and serine/threonine kinases. Tyrosine kinases are a family of tightly regulated enzymes, and the aberrant activation of various members of this family is one of the hallmarks of cancer. Tyrosine phosphorylation has been linked to multiple cell growth and differentiation pathways. Imatinib mesylate (1) is a tyrosine kinase inhibitor (TKI). An important characteristic of imatinib mesylate (1) is that it is an ATP-competitive inhibitor. It binds at the ATP binding site and blocks ATP binding thereby inhibiting kinase activities. 

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