Amino Acid Metabolism Abnormity and Microenvironment Variation Mediated Targeting and Controlled Glioma Chemotherapy.

Abstract

Energy metabolism abnormity is one of the most significant hallmarks of cancer. As a result, large amino acid transporter 1 (LAT1) is remarkably overexpressed in both blood-brain-barrier and glioma tumor cells, leading a rapid and sufficient substrate transportation. 3CDIT and 4CDIT are originally synthesized by modifying the existing most potent LAT1 substrate. 3CDIT is selected as its higher glioma-targeting ability. Since the microenvironment variation in tumor cells is another important feature of cancer, a great disparity in adenosine-5'-triphosphate (ATP) and glutathione (GSH) levels between extracellular and intracellular milieu can provide good possibilities for dual-responsive drug release in tumor cells. Doxorubicin (DOX) is successfully intercalated into the ATP aptamer DNA scaffolds, compressed by GSH-responsive polymer pOEI, and modified with 3CDIT to obtain 3CDIT-targeting pOEI/DOX/ATP aptamer nanoparticles (NPs). Enhanced NP accumulation and rapid GSH & ATP dual-responsive DOX release in glioma are demonstrated both in vitro and in vivo. More efficient therapeutic effects are shown with 3CDIT-targeting pOEI/DOX/ATP aptamer NPs than free DOX and no systemic toxicity is observed. Therefore, glioma-targeting delivery and GSH & ATP dual-responsive release guarantee an adequate DOX accumulation within tumor cells and ensure a safe and efficient chemotherapy for glioma.