In breast cancer, cyclooxygenase-2 (COX2), heparin-binding epidermal growth factor-like growth factor (HBEGF) and ST6 N-acetylgalactosaminide alpha-2,6-sialyltransferase 5 (ST6GALNAC5) facilitate endothelial adhesion and BBB transmigration. This evidence concerns the gene ST6GALNAC5 and breast cancer.