Comprehensive In silico Analysis of the Expression of Glycogenes in Breast Cancer

To elucidate the role of alterations to carbohydrate chains in cancer, we investigated changes in the expression of 107 glycogenes with the onset and progression of breast cancer by conducting an in silico analysis using GEO-registered data. A comparison between 43 breast tumors and paired normal controls (GSE15852) revealed significant changes in the expression of 24 glycogenes including the genes for 5 N-acetylgalactosaminyltransferases, 3 nucleotide sugar transporters, 3 asparagine-linked glycosylation-involved enzymes, 2 N-acetylglucosaminyl transferases, 2 fucosyltransferases, 2 sulfotransferases, 2 sulfatases, 1 glycosaminoglycan synthesis-involved enzyme, 1 glycosyltransferase, 1 glucosyltransferase, 1 sialyltransferase, and 1 N-acetylglucosaminidase. Furthermore, to clarify whether the expression of particular glycogenes changed dependent on the stage of cancer, we compared gene expression between preinvasive and invasive ductal carcinomas (GDS2045). The expression of 6 glycogenes exhibited significant changes in GDS2045. Notably, 3 of these genes were related to the sulfonation of carbohydrate chains. The upand down-regulated glycogenes were related to the synthesis of carbohydrate chains and the effects of changes in the expression of glycogenes on oncogenesis were discussed.