ST6GAL1 and cancer: The level of 2,6 sialylation is an important marker of cancer progression as α2,6-galactoside sialyltransferase 1 (ST6Gal1) (90) upregulation has been linked to aggressiveness of cancer cells (18, 27, 33, 44, 91–93) including colorectal (92, 94), gastric carcinoma (95), lungs (96), and brain (18).