Roles of glycogen metabolism in cancer cells. Under normal fed conditions, cancer cells present a low rate of glycogen turnover (top-left panel). Glycogen synthesis in
cancer cells is promoted by oncogene activation (Rab25) or tumour suppressor inhibition (VHL). Glycogen-derived glucose contributes to ATP generation, ROS scavenging and
biosynthesis of macromolecules, particularly nucleotides, and also proteins and lipids, required for cell proliferation