Potential Use of Glycine to Enhance Radiation Therapy for Prostate Cancer.

摘要

The project was intended to determine whether cytotoxic ionizing radiation induces upregulation of Hif1-alpha via a nitric oxide(NO)-mediated tumor stress response pathway and whether this effect can be inhibited by the administration of dietary glycine supplementation, which can suppress activation of the macrophages responsible for the NO. The ultimate goal was to test whether glycine effects tumor growth delay after ionizing radiation by suppressing this pathway. PC-3 cells transfected with a Hif-1 reporter detectable via bioluminescence imaging were implanted into nude mice and subjected to ionizing radiation (2-6 Gy), with or without prior and concurrent feeding with a glycine-rich diet. The results established the feasibility of this experimental model and confirm an increase in Hif-1; expression after ionizing radiation. Furthermore, the administration of dietary glycine supplementation suppressed radiation-induced Hif-1; expression and created a favorable growth delay in the xenograft model.