It is proposed, Phosphoribosyl Pyrophosphate (PRPP), (product of the pyrimidine biosynthesis key regulative enzyme Phosphoribosylpyrophosphate Synthase-1 (PRPS-1)), accelerates Epidermal Growth Factor (Egf) dependent cells proliferation. However, Egf or its fragments don't have direct impact on the PRPS-1. Reactive Oxygen Species, generated by purine catabolism regulative enzyme - Xanthine Oxidoreductase (XOR), might also influence on Egf mediated cells proliferation.
