Molecular Biology of the Cell Cycle: Potential for Therapeutic Applications in Radiation Oncology

The cell cycle was first described by radiation biologists more than 40 years ago. Since then, radiation oncologists have used information regarding the cell cycle, in particular cell cycle kinetics, to design various treatment protocols; these have resulted in only modest improvements in patient outcome. Over the past 10 to 15 years there has been an explosion of scientific knowledge regarding the cell cycle, in particular the molecular regulation of the cell cycle checkpoints. In this review we will discuss the genetic events involved in regulating the G1 and G2 checkpoints and how this information may lead to future therapeutic breakthroughs. In addition we will discuss the potential clinical impact of the recent cloning of the gene for ataxia telangiectasia.