ミカミ　テツオ   Mikami Tetsuo   三上　哲夫    所属   東邦大学  医学部 医学科    職種   教授
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Unique and selective expression of L-amino acid transporter 1 in human tissue as well as being an aspect of oncofetal protein
掲載誌名	正式名：Histology and histopathology 略　 称：Histol Histopathol ISSNコード：02133911/16995848
巻・号・頁	29(2),pp.217-227
著者・共著者	Nakada N, Mikami T†, Hana K, Ichinoe M, Yanagisawa N, Yoshida T, Endou H, Okayasu I
担当区分	2nd著者
発行年月	2014/02
概要	Dysregulated expression of L-type amino acid transporter 1 (LAT1), which transports large neutral amino acids, is a characteristic of various human cancers and possibly offers a molecular target for chemotherapy. LAT2, in contrast, shows lower expression in neoplasms. LAT1 is presumed to be a biomarker of many cancers, suggesting a kind of oncoprotein. However, no precise analysis of LAT1 and LAT2 expression has been performed in systemic normal tissues. To see characteristics of LAT1 and LAT2, immunohistochemical expression of LAT1 and LAT2 was assessed and compared in normal human systemic organs and tissues from 3 adults, 3 children and 3 fetuses in the present study. Cardiac muscles, hepatocytes, thymic epithelial cells and primitive neuroectodermal cells in fetus were positive with LAT1, whereas no expression was found in the respective adult tissues, indicating an aspect of oncofetal protein. In adult tissues, LAT1 was found to be expressed proximal to proliferative zones in gastrointestinal mucosa by double immunostaining of LAT1 and Ki-67. Testicular Sertoli cells, ovarian follicular cells, and pancreatic islet cells showed strong expression. Although the systemic capillary endothelium did not express LAT1, but did express LAT2, capillaries corresponding to the blood-brain, blood-follicle, and blood-retinal barriers demonstrated strong LAT1 immunoreactions. In conclusion, LAT1 was expressed in gonad tissues and several kinds of cells having special functions, as well as being discovered to be an aspect of oncofetal protein. In addition, ubiquitous LAT2 expression was confirmed immunohistochemically in systemic tissues, indicating constitutional function.
PMID	PMID: 23824658