The FGFR/MEK/ERK/brachyury pathway is critical for chordoma cell growth and survival.
Recent evidence suggests that the expression of brachyury is necessary for chordoma growth. However, the mechanism associated with brachyury-regulated cell growth is poorly understood. Fibroblast growth factor (FGF), a regulator of brachyury expression in normal tissue, may also play an important role in chordoma pathophysiology. Using a panel of chordoma cell lines, we explored the role of FGF signaling and brachyury in cell growth and survival. Western blots showed that all chordoma cell lines expressed fibroblast growth factor receptor 2 (FGFR2), FGFR3, mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK), whereas no cell lines expressed FGFR1 and FGFR4. Results of enzyme-linked immunosorbent assay indicated that chordoma cells produced FGF2. Neutralization of FGF2 inhibited MEK/ERK phosphorylation, decreased brachyury expression and induced apoptosis while reducing cell growth. Activation of the FGFR/MEK/ERK/brachyury pathway by FGF2-initiated phosphorylation of FGFR substrate 2 (FRS2)-α (Tyr196) prevented apoptosis while promoting cell growth and epithelial-mesenchymal transition (EMT). Immunofluorescence staining showed that FGF2 promoted the translocation of phosphorylated ERK to the nucleus and increased brachyury expression. The selective inhibition of FGFR, MEK and ERK phosphorylation by PD173074, PD0325901 and PD184352, respectively, decreased brachyury expression, induced apoptosis, and inhibited cell growth and EMT. Moreover, knockdown of brachyury by small hairpin RNA reduced FGF2 secretion, inhibited FGFR/MEK/ERK phosphorylation and blocked the effects of FGF2 on cell growth, apoptosis and EMT. Those findings highlight that FGFR/MEK/ERK/brachyury pathway coordinately regulates chordoma cell growth and survival and may represent a novel chemotherapeutic target for chordoma.
Department of Neurosurgery and Department of Radiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157 and Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21201, USA.
Yunping
Y
Hu
Department of Radiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157 and.
Akiva
A
Mintz
Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21201, USA.
Sagar R
SR
Shah
Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21201, USA.
Alfredo
A
Quinones-Hinojosa
Department of Neurosurgery and Department of Radiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157 and Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD 21201, USA whsu@wakehealth.edu.
Wesley
W
Hsu
D017209:Apoptosis; D015153:Blotting, Western; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D002817:Chordoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D058750:Epithelial-Mesenchymal Transition; D005326:Fetal Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D048369:MAP Kinase Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D020825:T-Box Domain Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000098908:Brachyury Protein
D005326:Fetal Proteins; D016222:Fibroblast Growth Factor 2; D048369:MAP Kinase Kinase 1; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D012333:RNA, Messenger; D051496:Receptor, Fibroblast Growth Factor, Type 1; D020825:T-Box Domain Proteins; D000098908:Brachyury Protein; C496348:FGFR1 protein, human; C535150:MAPK1 protein, human; C482125:MAP2K1 protein, human