Among the enzymes playing role in glycolysis,four allosteric PFKFB enzymes 1C4 expressed by four independent PFKFB genes, catalyze the rate-limiting phosphorylation of fructose-6-phosphate to fructose-1, 6-bisphosphate, using ATP as the energy source in the glycolysis pathway. Among these four allosteric enzymes, PFKFB3 enzyme retains the highest Kinase/Biphosphatase activity ratio and is expressed by PFKFB3 gene which has been demonstrated to be highly expressed in leukemic cells and in solid tumors. Moreover, mitogenic, hypoxic and inflammatory conditions have an inductive effect on the expression of PFKFB3. Hence upregulation of PFKFB genes specific to cancer cells compared to their normal counterparts (from the same patients) with more robust over-expression in breast and lung cancer make it a more appropriate target.
