I found an interesting article in the May 15th, 2007 Genetic Engineering News written by Patricia F. Dimond, Ph.D., that discusses how investigators are using cell-signaling pathways analysis to "characterize drug-resistance patterns in cancer cells, identify key signaling pathways impacted by specific drug treatments, and expand the druggable target space." By combining several applications of various molecular analysis technologies (gene array studies, protein expression, followed with the use of computer programs and databases to compute and analyze results), we can look beyond the single-target-based drug discovery and move towards "identifying key downstream proteins that are invovled in the pathway responses to drug-target interactions."
Dr. Dimond mentions that Oncotech's Director of Research (William Ricketts, Ph.D.) has clinically valididated an assay that is 99% accurate in determining tumor-cell drug resistance for certain patients with ovarian cancer that have tumors found to be resistant to certain platinum compounds. By being able to accurately identify each patient's resistance level (extreme drug resistant, intermediate drug resistant, or low drug resistant), and utilizing applied gene array technology from PathArt and Licor Biosciences, the research team can simultaneously analyze the protein expression and phosphorylation state to conclude that "differences in signal-transduction pathways are present at the gene and protein level in human tumors with differing cisplatin responses."
Incorporating several types of Molecular Analysis Technologies can help provide biomarkers of drug resistance, but as Dr. Ricketts explains, may also provide second-line indication for many targeted therapies.
For more info. please see Genetic Engineering News, March 15, 2007, "Cell Signaling Pathway Analysis" by Patricia F. Dimond, Ph.D., pg. 1, 22-23.