SLC29A1 and neoplasm: The nucleoside transporters ENT1-4, which may transport adenosine between the intracellular and extracellular spaces exhibited lineage-dependent expression, with ENT2 and ENT4 expressed by subsets of tumor cells (10.7% and 25.8% of tumor cells), while ENT1 and ENT3 were expressed by myeloid cells (66.9% and 39.7% of myeloid cells).