Nevertheless, as ST6GALNAC5 gene encodes a sialyltransferase involved in the biosynthesis of gangliosides and should, therefore, modify the cell surface glycosylation, mass spectrometry analysis was performed on BrM2 cells in order to identify a change in GSLs composition potentially involved in the interaction of breast cancer cells with the BBB. Here, ST6GALNAC5 is linked to breast cancer.