One of the known mechanisms that tumor cells utilize to limit T cell proliferation is lactic acid elevation which results in the blocking of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and 3-phosphoglycerate dehydrogenase, leading to the depletion of subsequent glycolytic intermediates including the 3-phosphoglycerate derivative serine which is known to be an essential factor for proliferation of T cells [20]. Here, PHGDH is linked to neoplasm.