Low-Level Radiation Improvement of Health and Therapy of Cancer

INTRODUCTION Observations of mice, rats, and human clinical trials demonstrate the efficacy of low-dose radiation immunotherapy. The immune system is an essential component of effective antimutagenic control of the enormous burden of relentless metabolic DNA alterations produced by reactive oxygen species (ROS) leaked from mitochondria. Our modeling of the human antimutagenic biosystem includes antioxidant prevention, enzymatic repair of DNA alterations and removal of persistent DNA alterations by apoptosis and the immune system that reduce DNA damage from ~10 DNA alterations/cell/d to ~1 “mutation”/cell/d. In comparison, only ~5x10 DNA alterations/cell/d and ~10 “mutations”/cell/d are produced by 0.1 cGy/y background low LET radiation (Figure 1). The accumulation of gene mutations with aging gradually impairs DNA damage-control. This in turn increases the rate of accumulation that is associated with increased risk of cancer with the 3 to the 5 power of age. Death from cancer at an early age is usually the result of severe genetic impairment of DNA damagecontrol. Similarly, high-dose, high dose rate radiation also increases the risk of cancer by exceeding the homeostatic capacity of the antimutagenic system.