variety of medicines and varying doses. It has been found that naturally occurring P-glycoproteins help in the build up of resistance to this multidrug technique. In a present study, the pharmokinetics of doxorubicin, a P-glycoprotein modulator, and GF120918, a novel potent P-glycoprotein inhibitor, were examined in cancer patients in a search for more selective modulation of multidrug resistance (MDR). (Sparreboom A., Planting A. S., Jewell R. C., van der Burg M. E., van der Gaast A., de Bruijn P., Loos W. J., Nooter K., Chandler L. H., Paul E. M., Wissel P. S., Verweij J.) Data indicates that GF120918 at the tested doses of combination treatment achieves plasma concentrations that reverse MDR in experimental models and it lacks the significant kinetic interaction with doxorubricin observed previously with other modulators. (7) Another study found that although multiple genes are involved in carcinogenisis. Carcinogenisis is the mutating of DNA because of a chemical in the body. Mutations of the p53 gene are the most frequent abnormality identified in human tumors. High levels of p53 expression and DNA-damaging agents work synergistcally to induce apoptosis (cell death) in cancer cells. Phase I clinical trials now show that p53 gene replacement therapy using both retroviral and adenoviral vectors(these are ways of getting the replacement genes into the cell) is feasible and safe. (Roth)Carcinoma, cancer of the epithelial cells, is a major cause of mortality in western societies. Clonal fixation and propagation of genetic changes due to oncogenes(cancer causing genes), sporadically accumulating in the epithelial cells, depend on growth factors and their surface receptors. One of the large families of receptors is that of the ErbB tyrosine kinases. ErbB-2 delays ligand dissociation, enhances coupling to the mitogen-activated protein kinase pathway, and impedes the rate of receptor downregulation. The realization that ErbB-...
