title: Epigenetically controlled fibroblast growth factor receptor 2 signaling imposes on the RAS/BRAF/mitogen-activated protein kinase pathway to modulate thyroid cancer progression.
abstract: Fibroblast growth factor (FGF) signals play fundamental roles in development and tumorigenesis. Thyroid cancer is an example of a tumor with nonoverlapping genetic mutations that up-regulate mitogen-activated protein kinase (MAPK). Here, we show that FGF receptor 1 (FGFR1), which is expressed mainly in neoplastic thyroid cells, propagates MAPK activation and promotes tumor progression. In contrast, FGFR2 is down-regulated in neoplastic thyroid cells through DNA promoter methylation. Reexpression of FGFR2 competes with FGFR1 for the immediate substrate FGFR substrate 2 to impede signaling upstream of the BRAF/MAPK pathway. These data unmask an epigenetically controlled FGFR2 signal that imposes precisely on the intragenically modified BRAF/MAPK pathway to modulate thyroid cancer behavior.
authors.affiliation: Department of Pathology, Princess Margaret Hospital, University Health Network, Toronto, Ontario, Canada.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Kondo
authors.forename: Lei
authors.initials: L
authors.lastname: Zheng
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Junichi
authors.initials: J
authors.lastname: Kurebayashi
authors.forename: Sylvia L
authors.initials: SL
authors.lastname: Asa
authors.forename: Shereen
authors.initials: S
authors.lastname: Ezzat
mesh_terms: D048708:Cell Growth Processes / Q000502:physiology; D045744:Cell Line, Tumor; D019175:DNA Methylation; D018450:Disease Progression; D015536:Down-Regulation; D044127:Epigenesis, Genetic; D006801:Humans; D020935:MAP Kinase Signaling System / Q000235:genetics; D009361:Neoplasm Invasiveness; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D051497:Receptor, Fibroblast Growth Factor, Type 2 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D013964:Thyroid Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D014162:Transfection; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D034741:RNA, Small Interfering; C496348:FGFR1 protein, human; C496353:FGFR2 protein, human; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D018631:ras Proteins