title: Characterization of functional transient receptor potential melastatin 8 channels in human pancreatic ductal adenocarcinoma cells.
abstract: OBJECTIVE
  Recently, the transient receptor potential melastatin 8 (TRPM8) channel has emerged as a putative biomarker for pancreatic ductal adenocarcinoma (PDA). This study aimed to evaluate the expression of TRPM8 and its modulation by specific agonists and antagonists in PDA cells.
  
  
  METHODS
  We examined the protein expression of TRPM8 in 3 different PDA cell lines and compared it with a nontumoral epithelial cell line of human pancreatic origin using Western blotting and immunocytochemical analysis. To assess the function of TRPM8 channels, we measured the TRPM8 currents in whole-cell mode of the patch clamp technique. To explore the putative involvement of TRPM8 in cell migration, we investigated the motility of PDA cells using the scratch-wound assay.
  
  
  RESULTS
  Pancreatic ductal adenocarcinoma cells express functional plasma membrane TRPM8 channels, which are responsive after exposure to agonists (menthol and icilin) and antagonists N-(3-aminopropyl)-2-{[(3-methylphenyl) methyl]oxy}-N-(2-thienylmethyl)benzamide hydrochloride salt. The silencing of TRPM8 expression by small interfering RNA augments the migration of PDA cells. Conversely, the activated form of TRPM8 inhibits PDA cell motility.
  
  
  CONCLUSIONS
  An unglycosylated TRPM8 protein is expressed and is functional in the membrane of PDA cells. Transient receptor potential melastatin 8 inhibits the migration of PDA cells, suggesting a putative role as a biomarker or target for this channel for PDA therapy.
authors.affiliation: From the *Center of Digestive Disease and Liver Transplantation, Fundeni Clinical Institute; †Department of Molecular and Cell Biology, Romanian Academy Institute of Biochemistry; ‡Department of Anatomy, Physiology, and Biophysics, Faculty of Biology, University of Bucharest, Bucharest, Romania; §Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA; and ∥Division of Molecular Pathology, Department of Pathology, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Dana
authors.initials: D
authors.lastname: Cucu
authors.forename: Gabriela
authors.initials: G
authors.lastname: Chiritoiu
authors.forename: Stefana
authors.initials: S
authors.lastname: Petrescu
authors.forename: Alexandru
authors.initials: A
authors.lastname: Babes
authors.forename: Luciana
authors.initials: L
authors.lastname: Stanica
authors.forename: Dan G
authors.initials: DG
authors.lastname: Duda
authors.forename: Akira
authors.initials: A
authors.lastname: Horii
authors.forename: Simona Olimpia
authors.initials: SO
authors.lastname: Dima
authors.forename: Irinel
authors.initials: I
authors.lastname: Popescu
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D001549:Benzamides / Q000494:pharmacology; D015153:Blotting, Western; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002460:Cell Line; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D007150:Immunohistochemistry; D008564:Membrane Potentials / Q000187:drug effects; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008610:Menthol / Q000494:pharmacology; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D018408:Patch-Clamp Techniques; D011744:Pyrimidinones / Q000494:pharmacology; D034622:RNA Interference; D050053:TRPM Cation Channels / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013876:Thiophenes / Q000494:pharmacology
chemical_list: D001549:Benzamides; D008565:Membrane Proteins; C532415:N-(3-aminopropyl)-2-(((3-methylphenyl) methyl)oxy)-N-(2-thienylmethyl)benzamide hydrochloride salt; D011744:Pyrimidinones; D050053:TRPM Cation Channels; C425966:TRPM8 protein, human; D013876:Thiophenes; D008610:Menthol; C490483:icilin