title: CCDC88A, a prognostic factor for human pancreatic cancers, promotes the motility and invasiveness of pancreatic cancer cells.
abstract: Coiled-Coil Domain Containing 88A (CCDC88A) was identified as a substrate of the serine/threonine kinase Akt that is capable of binding to the actin cytoskeleton. The aim of this study was to investigate the potential role of CCDC88A in the migration and invasiveness of pancreatic ductal adenocarcinoma (PDAC) cells.
  
  
  
  Immunohistochemistry was performed to determine whether high CCDC88A expression in human PDAC tissues is correlated with poor prognosis. Immunoprecipitation, immunoblotting and immunocytochemistry were performed to determine the intracellular distribution of CCDC88A, and its association with the serine/threonine kinase Akt and actin-filaments in PDAC cells. Phosphoprotein array analysis was performed to determine CCDC88A-associated intracellular signaling pathways. Finally, immunofluorescence analyses and Matrigel invasion assays were performed to examine the effects of CCDC88A on the formation of cell protrusions and PDAC cell invasion.
  
  
  
  Expression of CCDC88A in PDAC tissue was significantly correlated with overall survival. CCDC88A was co-localized with peripheral actin structures in cell protrusions of migrating PDAC cells. Knockdown of CCDC88A inhibited the migration and invasiveness of PDAC cells through a decrease in cell protrusions. Although CCDC88A has been previously reported to be a binding partner and substrate of Akt, the level of active Akt was not associated with the translocation of CCDC88A towards cell protrusions. CCDC88A-dependent promotion of cell migration and invasiveness was not modulated by Akt signaling. Knockdown of CCDC88A decreased phosphorylated Src and ERK1/2 and increased phosphorylated AMPK1 in PDAC cells. Knockdown of AMPK1 inhibited the migration and invasiveness of PDAC cells. The combined data suggest that CCDC88A may be a useful marker for predicting the outcome of patients with PDAC and that CCDC88A can promote PDAC cell migration and invasion through a signaling pathway that involves phosphorylation of Src and ERK1/2 and/or dephosphorylation of AMPK1.
  
  
  
  CCDC88A was accumulated in cell protrusions, contributed to the formation of membrane protrusions, and increased the migration and invasiveness of PDAC cells.
authors.affiliation: Department of Gastroenterology and Hepatology; Kochi Medical School, Kochi University, Kochi, Japan. jm-tanouchi@kochi-u.ac.jp.
authors.forename: Aki
authors.initials: A
authors.lastname: Tanouchi
authors.affiliation: Department of Gastroenterology and Hepatology; Kochi Medical School, Kochi University, Kochi, Japan.|Departments of Endoscopic Diagnostics and Therapeutics, Kochi Medical School, Kochi University, Kohasu, Oko-cho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Taniuchi
authors.affiliation: Department of Pathology, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Mutsuo
authors.initials: M
authors.lastname: Furihata
authors.affiliation: Department of Pathology, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Naganuma
authors.affiliation: Department of Surgery, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Dabanaka
authors.affiliation: Department of Surgery, Matsuyama Shimin Hospital, Matsuyama, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kimura
authors.affiliation: Department of Surgery, Matsuyama Shimin Hospital, Matsuyama, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Watanabe
authors.affiliation: Department of Gastroenterology and Hepatology; Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Takuhiro
authors.initials: T
authors.lastname: Kohsaki
authors.affiliation: Department of Pharmacology, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shimizu
authors.affiliation: Department of Pharmacology, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Motoaki
authors.initials: M
authors.lastname: Saito
authors.affiliation: Department of Surgery, Kochi Medical School, Kochi University, Kochi, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hanazaki
authors.affiliation: Department of Gastroenterology and Hepatology; Kochi Medical School, Kochi University, Kochi, Japan.|Departments of Endoscopic Diagnostics and Therapeutics, Kochi Medical School, Kochi University, Kohasu, Oko-cho, Nankoku, Kochi, 783-8505, Japan.
authors.forename: Toshiji
authors.initials: T
authors.lastname: Saibara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008840:Microfilament Proteins / Q000378:metabolism*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D010750:Phosphoproteins / Q000378:metabolism*; D011379:Prognosis; D060066:Protein Interaction Maps; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D016019:Survival Analysis; D015854:Up-Regulation; D033921:Vesicular Transport Proteins / Q000378:metabolism*
chemical_list: C502451:CCDC88A protein, human; D008840:Microfilament Proteins; D010750:Phosphoproteins; D033921:Vesicular Transport Proteins; D051057:Proto-Oncogene Proteins c-akt
keywords: AMPK1; Akt-binding protein; Cell invasion; Cell protrusions; Pancreatic cancer