title: Expression of LAT1 predicts risk of progression of transitional cell carcinoma of the upper urinary tract.
abstract: L-type amino acid transporter 1 (LAT1), a neutral amino acid transporter, requires covalent association with the heavy chain of 4F2 cell surface antigen (4F2hc) for its functional form. We investigated the importance of LAT1 and 4F2hc expressions to progression in upper urinary tract cancer. We examined their expressions and their relationships to clinicopathologic parameters and clinical outcome in 124 cases. Positive expressions of LAT1 (protein and messenger ribonucleic acid) and 4F2hc (protein) were recognized in 79.8, 89.5, and 87.9% of tumor samples, respectively. In tumor cells, LAT1 protein was detected either as nodular granules within the cytoplasm or diffusely within the cytoplasm and/or on plasma membrane. In the normal urothelium, its expression was detected as nodular granules within the cytoplasm. A correlation with stage was shown for LAT1 protein expression and for a cooperative expression of LAT1 protein with 4F2hc protein (active form of LAT1 protein). Further, in all tumors, a cooperative expression of LAT1 protein and 4F2hc protein was significantly correlated with both overall and disease-free survival rates in the univariate analysis but not in the multivariate analysis. In conclusion, the detection of the active form of LAT1 protein would appear to be of value in informing the risk of progression in transitional cell carcinoma of the upper urinary tract.
authors.affiliation: Department of Pathology and Laboratory Medicine, National Defense Medical College, Tokorozawa, 359-8513, Japan. nknsknak@ndmc.ac.jp
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Nakanishi
authors.forename: Sho
authors.initials: S
authors.lastname: Ogata
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Matsuo
authors.forename: Yoshikatsu
authors.initials: Y
authors.lastname: Kanai
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Endou
authors.forename: Sadayuki
authors.initials: S
authors.lastname: Hiroi
authors.forename: Susumu
authors.initials: S
authors.lastname: Tominaga
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Aida
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Kasamatsu
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kawai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015153:Blotting, Western; D002295:Carcinoma, Transitional Cell / Q000737:chemistry / Q000473:pathology*; D002462:Cell Membrane / Q000473:pathology; D003593:Cytoplasm / Q000473:pathology; D018450:Disease Progression; D005260:Female; D027261:Fusion Regulatory Protein-1 / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D027283:Large Neutral Amino Acid-Transporter 1 / Q000032:analysis* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis; D012307:Risk Factors; D014571:Urologic Neoplasms / Q000737:chemistry* / Q000473:pathology*
chemical_list: D027261:Fusion Regulatory Protein-1; D027283:Large Neutral Amino Acid-Transporter 1; D012333:RNA, Messenger