title: Leucine-rich repeat-containing G protein-coupled receptor 5 expression in ductular reactions after chemotherapy for metastatic colorectal cancer.
abstract: OBJECTIVE
  Oval cells with ductular reactions (DR) in damaged liver are referred to as "intermediate hepatobiliary cells". In a preliminary study, we had found expression of the leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) known as a potential marker for stem cells in the small intestine and colon in DR in liver damaged by chemotherapy for metastatic colorectal cancer (CRC). The aim of this study was to confirm LGR expression in DR in damaged liver after chemotherapy.
  
  
  METHODS
  A total of 68 liver specimens obtained after surgical resection were stained with monoclonal antibodies for cytokeratin (CK)7, neural cell adhesion molecule (NCAM; a bile ductular and liver progenitor cell marker), CD133 (a candidate stem cell marker of hepatocellular carcinoma as well as CRC) and LGR5. Additionally, these mRNA levels were investigated according to the location in damaged liver after chemotherapy using microdissected specimens.
  
  
  RESULTS
  We observed that LGR5 was expressed in DR with CD133, CK7 and NCAM expression. By contrast, LGR5, CD133 and NCAM were not expressed in mature bile ducts with CK7. In transcriptional analysis, LGR5 mRNA levels in fibrotic tissue including DR were higher compared with that in adjacent normal liver without significant difference.
  
  
  CONCLUSIONS
  These findings suggest that LGR5 may be involved in maintaining DR in damaged liver.
authors: Department of Gastrointestinal and Pediatric Surgery,              Division of Reparative Medicine, Institute of Life Sciences, Mie University Graduate School of Medicine, Mie. Japan.
authors: Susumu
authors: S
authors: Saigusa
authors: Koji
authors: K
authors: Tanaka
authors: Yuji
authors: Y
authors: Toiyama
authors: Kohei
authors: K
authors: Matsushita
authors: Mikio
authors: M
authors: Kawamura
authors: Yoshinaga
authors: Y
authors: Okugawa
authors: Keiichi
authors: K
authors: Uchida
authors: Yasuhiro
authors: Y
authors: Inoue
authors: Yasuhiko
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authors: Mohri
authors: Masato
authors: M
authors: Kusunoki