COMPARISON OF TWO HUMAN CELL LINES FOLLOWING EXPOSURE TO LOW DOSE RADIATION AND TREATMENT WITH SOYBEAN MISO AND ITS ACTIVE INGREDIENT GENISTEIN

Abstract

Exposure to radiation is increasingly becoming a worldwide health issue. Because of this, the need for effective radioprotectors is critical. This need is not met by amifostine, the current "gold standard" in radioprotectors, due to its limited availability and potentially severe side effects. The fermented soy product miso has been credited with a host of beneficial effects, among which are radioprotection, and, as a common food, miso is readily available, known to be safe and is easily administered. As such, it is the hypothesis of this dissertation that miso may be an effective radioprotector. Unfortunately, few rigorous studies of miso's reputed actions have been undertaken. It is the objective of this investigation, therefore, to better identify and characterize the radioprotective and antioncogenic properties of miso and its most abundant active ingredient genistein. To accomplish this, experiments were designed using tumorigenic (PC3 cells) and non-tumorigenic (RWPE-1 cells) experimental prostate models to characterize the effects of miso and genistein both alone and following a series of low dose radiation exposures. Results demonstrated that neither miso nor genistein appeared to display radioprotective abilities in the radiation dose range used in this investigation. However, both compounds induced a strong growth inhibitory effect that appeared to synergize with radiation to significantly reduce cell survival in a manner that preferentially enhanced tumor cell kill over non-tumor cell kill, suggesting potential antioncogenic potential for these compounds.