title: Overexpression of CEACAM6 promotes insulin-like growth factor I-induced pancreatic adenocarcinoma cellular invasiveness.
abstract: Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is a glycosylphosphatidylinositol-linked immunoglobulin superfamily member that is overexpressed in a variety of human cancers. We have recently reported that suppression of CEACAM6 expression impairs pancreatic adenocarcinoma progression in vivo. In order to characterize the mechanisms through which CEACAM6 influences the malignant phenotype, CEACAM6-overexpressing Capan2 pancreatic adenocarcinoma cells were established by stable transfection. We determined the effect of CEACAM6 overexpression on cellular invasiveness towards insulin-like growth factor I (IGF-I), a peptide of critical importance in pancreatic cancer malignant cellular behavior and tumor progression. IGF-I-induced cellular invasiveness and IGF-IR expression were significantly increased in clones overexpressing CEACAM6. Using inhibitory anti-IGF-IR antibody, a requirement for IGF-IR signaling in the enhanced invasiveness towards IGF-I induced by CEACAM6 overexpression was confirmed. CEACAM6-overexpressing clones exhibited increased Akt and c-Src kinase activities, as well as higher levels of matrix metalloproteinase-2 (MMP-2) expression and activity in the presence of IGF-I. While Akt kinase is both necessary and sufficient to induce IGF-IR upregulation, c-Src kinase activity is necessary, but alone is insufficient to upregulate IGF-IR expression. CEACAM6 is an important determinant of pancreatic adenocarcinoma malignant cellular behavior and, together with its downstream targets, warrants further investigation as a therapeutic target in this disease.
authors.affiliation: Department of Surgery, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Duxbury
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ito
authors.forename: Eric
authors.initials: E
authors.lastname: Benoit
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Zinner
authors.forename: Stanley W
authors.initials: SW
authors.lastname: Ashley
authors.forename: Edward E
authors.initials: EE
authors.lastname: Whang
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D015703:Antigens, CD; D000951:Antigens, Neoplasm / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D000081247:CSK Tyrosine-Protein Kinase; D015815:Cell Adhesion Molecules / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D058851:GPI-Linked Proteins; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D020778:Matrix Metalloproteinase 2 / Q000187:drug effects / Q000378:metabolism; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D017526:Receptor, IGF Type 1 / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D015854:Up-Regulation; D019061:src-Family Kinases
chemical_list: D015703:Antigens, CD; D000951:Antigens, Neoplasm; D000081247:CSK Tyrosine-Protein Kinase; D015815:Cell Adhesion Molecules; D058851:GPI-Linked Proteins; D007334:Insulin-Like Growth Factor I; D020778:Matrix Metalloproteinase 2; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins; D051057:Proto-Oncogene Proteins c-akt; D017526:Receptor, IGF Type 1; D019061:src-Family Kinases; C504117:CEACAM6 protein, human; C000631346:CSK protein, human; C494918:AKT1 protein, human