NANS and neoplasm: Tumor cells highly expressed donor synthesis genes (NANS, CMAS, and the transporter SLC35A1), while the stroma showed enriched expression of sialyltransferases involved in α2-3, α2-6 and α2-8 sialylation (ST3GAL2, ST3GAL5, ST6GAL2, ST6GALNAC5, ST6GALNAC6, ST8SIA1 and ST8SIA2) (Fig. 1e).