SLC29A1 and pancreatic neoplasm: Similar to the related nucleoside analog termed cytarabine (Ara-C) [28], GEM is taken up within pancreatic cancer cells through equilibrative nucleoside transporter-1 (hENT1) [29], and subjected to deoxycytidine kinase (dCK)-mediated phosphorylation to become an active form (dFdCTP).