Abstract: L-amino acid transporter 1 ( LAT1) is a member of L-amino transporter family and an important heterodi⁃ meric amino acid transporter that belongs to subfamily of SLC7. LAT1 mainly mediates trans-membrane transportation of those neutral amino acids that had cyclobenzene or long side chains with high molecular mass such as L-Leu, L-Met and LPhe as well as some amino acid analogues such as melphalan, L-DOPA and thyroxine in a Na+ and ATP-independent diffu⁃ sion. As LAT1 was abnormally overexpressed in various transformed cell lines, it might be related with tumor stage and prog⁃ nosis. It is not only a biomarker that specifically expressed in some tumor cells but also plays an important role in tumor diag⁃ nosis and therapy. Here we demonstrate the structure of LAT1 and its mechanism in transport peculiarity. We also reviewed the development of LAT1 in tumor diagnosis and treatment.

Key words: amino acid transport systems, neoplasms, review, L-type amino acid transporter, tumor diogonsis, tumor therapy