ABSTRACT

A major focus of much of our work has been the elucidation of molecular and cellular mechanisms and the identication of gene and protein targets in cancer development and prevention. A  signicant outcome of these investigations has been a clarication of signal transduction pathways induced by  tumor promoters in cancer development. Signal transduction is the process by which information from a stimulus outside the cell is transmitted through the cell membrane (e.g., through a protein receptor) into the cell and along an intracellular chain of signaling proteins (e.g., protein kinases) to transcription factors, causing a cellular response (Figure 13.1). A transcription factor is comprised of one or more proteins that bind to a specic DNA sequence and act to initiate transcription that results in production of a specic protein product. DNA binding is commonly induced by protein kinases. Transcription factors acting downstream of these signaling cascades are heavily involved in numerous cellular functions that include survival, development, proliferation, apoptosis, cell cycle regulation, inammation, and differentiation (Figure 13.1).