Dan A. Laheru, MD

The identification of key signaltransduction pathways and, inparticular, specific proteins thatare involved in the regulation of cancercell growth has provided unprecedentedopportunities for researchersinterested in targeted cancer treatment.The identification of molecular target-specific therapy offers the potentialof maximal therapeutic benefitwhile minimizing toxicity to normalcells. The accomplishment that led tothe sequencing and analysis of theentire human genome in 2001 has providedresearchers with the basic criticaltools to begin to identify anddifferentiate cancer from normal tissueat the genetic level.[1,2] Whilethe implications of this landmarkachievement are still being realized,it has become evident that the identificationof critical genes and proteinsinvolved in cell division and growthare just the beginning. The complexrelationships between multiple signaltransduction pathways, the surroundingtumor microenvironment, andpathways involved in immune-systemregulation have gained new appreciation.The ability to manipulate thesemultiple interactive systems with targetedtherapies represents a new treatmentparadigm in oncology.