GAPDH and B-cell chronic lymphocytic leukemia: The most studied example of nutrient competition is the increased glucose consumption by malignant cells caused by elevated expression levels of glucose transporters and enzymes of the glycolytic machinery {as seen in BCR-DLBCL [e.g., GAPDH expression (52) and lactate secretion (13)], transformed FL [e.g., GAPDH and aldolase A (27, 28)], MCL [e.g., glycolytic flux (33)], and CLL in the LN-/BM-niche [e.g., glycolytic flux and key glycolytic enzymes (44)]}.