Scientific basis for cancer prevention. Intermediate cancer markers.

Promising cancer clinical trials results involving the disruption of early stages of cancer with intervention agents such as tamoxifen or retinoids have led to significant new research interest in developing preventative strategy for the control of epithelial cancers. Key to the efficient progress in this field is a clear understanding of the complex biology of the early stages of cancerization that proceed on the epithelial surface. Systematic analysis of the biology of strategic targets such as growth factors is one approach to this problem. Gastrin-releasing peptide is an autocrine growth factor for certain types of lung cancer cells. Mechanisms involved in the production and activation of this peptide are discussed as an example of how rational approaches to neutralization of cancer promotion biology can be achieved. The tools to monitor the success of this type of intervention also emerge from the understanding of the biology of growth factors, and intermediate end point markers that determine the presence or effects of a growth factor are attractive candidates for evaluation. Additional biologic tools reflecting the early stages of the cancer process need to be validated for use in serially evaluating the status of the relevant epithelium so that the ongoing success of a cancer intervention procedure can be established. Through this type of translational research, important applications of molecular biology may greatly improve the success of preventative strategies for cancer control.