title: The mucin MUC4 and its membrane partner ErbB2 regulate biological properties of human CAPAN-2 pancreatic cancer cells via different signalling pathways.
abstract: The mucin MUC4 and its membrane partner the ErbB2 oncogenic receptor are potential interacting partners in human pancreatic tumour development. However, the way they function is still largely unknown. In this work, we aimed to identify the cellular mechanisms and the intracellular signalling pathways under the control of both ErbB2 and MUC4 in a human pancreatic adenocarcinomatous cell line. Using co-immunoprecipitation and GST pull-down, we show that MUC4 and ErbB2 interact in the human pancreatic adenocarcinomatous cell line CAPAN-2 via the EGF domains of MUC4. Stable cell clones were generated in which either MUC4 or ErbB2 were knocked down (KD) by a shRNA approach. Biological properties of these cells were then studied in vitro and in vivo. Our results show that ErbB2-KD cells are more apoptotic and less proliferative (decreased cyclin D1 and increased p27kip1 expression) while migration and invasive properties were not altered. MUC4-KD clones were less proliferative with decreased cyclin D1 expression, G1 cell cycle arrest and altered ErbB2/ErbB3 expression. Their migration properties were reduced whereas invasive properties were increased. Importantly, inhibition of ErbB2 and MUC4 expression did not impair the same signalling pathways (inhibition of MUC4 expression affected the JNK pathway whereas that of ErbB2 altered the MAPK pathway). Finally, ErbB2-KD and MUC4-KD cells showed impaired tumour growth in vivo. Our results show that ErbB2 and MUC4, which interact physically, activate different intracellular signalling pathways to regulate biological properties of CAPAN-2 pancreatic cancer cells.
authors.affiliation: Inserm, UMR837, Jean Pierre Aubert Research Center, Team #5 Mucins, epithelial differentiation and carcinogenesis, Lille, France. nicolas.jonckheere@inserm.fr
authors.forename: Nicolas
authors.initials: N
authors.lastname: Jonckheere
authors.forename: Nicolas
authors.initials: N
authors.lastname: Skrypek
authors.forename: Johann
authors.initials: J
authors.lastname: Merlin
authors.forename: Anne Frédérique
authors.initials: AF
authors.lastname: Dessein
authors.forename: Patrick
authors.initials: P
authors.lastname: Dumont
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Leteurtre
authors.forename: Ann
authors.initials: A
authors.lastname: Harris
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Desseyn
authors.forename: Christiane
authors.initials: C
authors.lastname: Susini
authors.forename: Frédéric
authors.initials: F
authors.lastname: Frénois
authors.forename: Isabelle
authors.initials: I
authors.lastname: Van Seuningen
mesh_terms: D000818:Animals; D017209:Apoptosis; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008024:Ligands; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D051379:Mice; D016513:Mice, SCID; D018613:Microscopy, Confocal / Q000379:methods; D055264:Mucin-4 / Q000502:physiology*; D009361:Neoplasm Invasiveness; D009368:Neoplasm Transplantation; D020411:Oligonucleotide Array Sequence Analysis; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D008024:Ligands; D048670:MAP Kinase Kinase 4; D055264:Mucin-4; D034741:RNA, Small Interfering; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human; C524056:Erbb2 protein, mouse