title: CD166/ALCAM expression is characteristic of tumorigenicity and invasive and migratory activities of pancreatic cancer cells.
abstract: BACKGROUND
  CD166, also known as activated leukocyte cell adhesion molecule (ALCAM), is expressed by various cells in several tissues including cancer. However, the role of CD166 in malignant tumors is controversial, especially in pancreatic cancer. This study aimed to clarify the role and significance of CD166 expression in pancreatic cancer.
  
  
  METHODS
  We performed immunohistochemistry and flow cytometry to analyze the expression of CD166 in surgical pancreatic tissues and pancreatic cancer cell lines. The differences between isolated CD166+ and CD166- pancreatic cancer cells were analyzed by invasion and migration assays, and in mouse xenograft models. We also performed quantitative RT-PCR and microarray analyses to evaluate the expression levels of CD166 and related genes in cultured cells.
  
  
  RESULTS
  Immunohistochemistry revealed high expression of CD166 in pancreatic cancer tissues (12.2%; 12/98) compared with that in normal pancreas controls (0%; 0/17) (p = 0.0435). Flow cytometry indicated that CD166 was expressed in 33.8-70.2% of cells in surgical pancreatic tissues and 0-99.5% of pancreatic cancer cell lines. Invasion and migration assays demonstrated that CD166- pancreatic cancer cells showed stronger invasive and migratory activities than those of CD166+ cancer cells (p<0.05). On the other hand, CD166+ Panc-1 cells showed a significantly stronger colony formation activity than that of CD166- Panc-1 cells (p<0.05). In vivo analysis revealed that CD166+ cells elicited significantly greater tumor growth than that of CD166- cells (p<0.05) in both subcutaneous and orthotopic mouse tumor models. mRNA expression of the epithelial-mesenchymal transition activator Zeb1 was over-expressed in CD166- cells (p<0.001). Microarray analysis showed that TSPAN8 and BST2 were over-expressed in CD166+ cells, while BMP7 and Col6A1 were over-expressed in CD166- cells.
  
  
  CONCLUSIONS
  CD166+ pancreatic cancer cells are strongly tumorigenic, while CD166- pancreatic cancer cells exhibit comparatively stronger invasive and migratory activities. These findings suggest that CD166 expression is related to different functions in pancreatic cancer cells.
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Fujiwara
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kenoki
authors.initials: K
authors.lastname: Ohuchida
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Sada
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Horioka
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Charles D
authors.initials: CD
authors.lastname: Ulrich
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Research Fellow of the Japan Society for the Promotion of Science, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Shindo
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Ohtsuka
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Shunichi
authors.initials: S
authors.lastname: Takahata
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan; Kyushu University Hospital Cancer Center, Fukuoka, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Mizumoto
authors.affiliation: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Oda
authors.affiliation: Department of Surgery and Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Tanaka
mesh_terms: D020410:Activated-Leukocyte Cell Adhesion Molecule / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D055419:Bone Morphogenetic Protein 7 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D054443:Cell Migration Assays; D002465:Cell Movement / Q000235:genetics; D024142:Collagen Type VI / Q000235:genetics / Q000378:metabolism; D058750:Epithelial-Mesenchymal Transition; D005434:Flow Cytometry; D058851:GPI-Linked Proteins / Q000235:genetics / Q000378:metabolism; D064593:Heterografts / Q000378:metabolism; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D009361:Neoplasm Invasiveness / Q000235:genetics; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D059470:Tetraspanins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D000071799:Zinc Finger E-box-Binding Homeobox 1; D000074010:Bone Marrow Stromal Antigen 2
chemical_list: D020410:Activated-Leukocyte Cell Adhesion Molecule; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D055419:Bone Morphogenetic Protein 7; D024142:Collagen Type VI; D058851:GPI-Linked Proteins; D018398:Homeodomain Proteins; D059470:Tetraspanins; D014157:Transcription Factors; D000071799:Zinc Finger E-box-Binding Homeobox 1; C525819:BMP7 protein, human; C094572:BST2 protein, human; D000074010:Bone Marrow Stromal Antigen 2; C553839:Col6a1 protein, human; C065609:TSPAN8 protein, human; C486307:ZEB1 protein, human