Model of the expression of uMtCK in prostate cancer progression. Top panel: in normal cells, uMtCK is expressed in the intermembrane space of mitochondria where it transfers the phosphate group of ATP to creatine to yield phosphocreatine. This, in turn, is used as an ATP stock. Middle panel: similarly, in low Gleason grade carcinoma, uMtCK is expressed in mitochondria and functions in energy transfer. Bottom panel: in high Gleason grade carcinoma, uMtCK is not expressed. Instead, HKII is localized at mitochondria, suggesting a shift to increased aerobic glycolysis.