Therefore, in targeting PGK the exact determination of the timing of administration of the inhibitory compound is required, depending on whether the goal is to activate or inhibit ECM turnover, quantify oxygenated/hypoxic areas, or manipulate the anoxic ratio of the tumor population. PGK also shows maximum activity at a cellular pH range similar to that of cancer cells [174,175], which is alkaline [176]. This evidence concerns the gene PRKG1 and cancer.