Oncogenes as novel targets for cancer therapy (part II): Intermediate signaling molecules.

This is the second part of a four-part review on potential therapeutic targeting of oncogenes. The previous part introduced the new technologies responsible for the advancement of oncogene identification, target validation, and drug design. Because of such advances, new specific and more efficient therapeutic agents can be developed for cancer. This part of the review continues the exploration of various oncogenes, which we have grouped within seven categories: growth factors, tyrosine kinases, intermediate signaling molecules, transcription factors, cell cycle regulators, DNA damage repair genes, and genes involved in apoptosis. Part I included a discussion of growth factors and tyrosine kinases. This portion of the review covers intermediate signaling molecules and the various strategies used to inhibit their expression or decrease their activities.