Cancer drug delivery targeting amino acid transporters

Among amino acid transporters upregulated in tumor cells, LAT1 (SLC7A5) is the most favorable for the drug delivery to cancers due to its cancer-selective expression and broad substrate selectivity. LAT1 is responsible for the cancer delivery of anti-tumor phenylalanine-mustard melphalan and L-p-boronophenylalanine used for boron neutron capture therapy. LAT1 is also a target of PET imaging probe delivery. Most of amino acid probes target LAT1, whereas only FAMT is LAT1-selective. FAMT, therefore, exhibits the most remarkable cancer-selective accumulation. Cancer-selective drug design including the idea of amino acid-based pro-drugs would be possible based on the LAT1-selectivity and property as a LAT1 substrate.