Enzyme blocking may be a new tool as researchers learn more about how genes are activated. Tumor cell proliferation and tumor growth were inhibited in new research conducted by researchers at The University of Texas MD Anderson Cancer Center. Two enzymes were studied, Gen5 and alpha-KGDH. Gen5 delivers molecular components that allow genes to be switched on and off. When alpha-KGDH was blocked from entering the cell nucleus, brain tumor cell proliferation and tumor growth were inhibited. Further, brain tumor cell proliferation and tumor growth were inhibited when Gen5 was prevented from binding to alpha-KGDH-generated succinyl-coenzyme A. The researchers believe these findings amplify the significance of gene expression as regulated by Gen5 and its interactions with the metabolic enzyme alpha-KGDH in tumor cell formation and proliferation.