Sensitivity of Melanoma Cells to EGFR and FGFR Activation but Not Inhibition is Influenced by Oncogenic BRAF and NRAS Mutations.
BRAF and NRAS are the two most frequent oncogenic driver mutations in melanoma and are pivotal components of both the EGF and FGF signaling network. Accordingly, we investigated the effect of BRAF and NRAS oncogenic mutation on the response to the stimulation and inhibition of epidermal and fibroblast growth factor receptors in melanoma cells. In the three BRAF mutant, two NRAS mutant and two double wild-type cell lines growth factor receptor expression had been verified by qRT-PCR. Cell proliferation and migration were determined by the analysis of 3-days-long time-lapse videomicroscopic recordings. Of note, a more profound response was found in motility as compared to proliferation and double wild-type cells displayed a higher sensitivity to EGF and FGF2 treatment when compared to mutant cells. Both baseline and induced activation of the growth factor signaling was assessed by immunoblot analysis of the phosphorylation of the downstream effectors Erk1/2. Low baseline and higher inducibility of the signaling pathway was characteristic in double wild-type cells. In contrast, oncogenic BRAF or NRAS mutation did not influence the response to EGF or FGF receptor inhibitors in vitro. Our findings demonstrate that the oncogenic mutations in melanoma have a profound impact on the motogenic effect of the activation of growth factor receptor signaling. Since emerging molecularly targeted therapies aim at the growth factor receptor signaling, the appropriate mutational analysis of individual melanoma cases is essential in both preclinical studies and in the clinical trials and practice.
2nd Department of Pathology, Semmelweis University, Üllői út 93, H-1091, Budapest, Hungary.
Tamás
T
Garay
Eszter
E
Molnár
Éva
É
Juhász
Viktória
V
László
Tamás
T
Barbai
Judit
J
Dobos
Karin
K
Schelch
Christine
C
Pirker
Michael
M
Grusch
Walter
W
Berger
József
J
Tímár
Balázs
B
Hegedűs
D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D004252:DNA Mutational Analysis; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000235:genetics*; D006801:Humans; D008545:Melanoma / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D010766:Phosphorylation / Q000187:drug effects; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D008565:Membrane Proteins; D012333:RNA, Messenger; C512478:EGFR protein, human; D066246:ErbB Receptors; C496348:FGFR1 protein, human; D051496:Receptor, Fibroblast Growth Factor, Type 1; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D020558:GTP Phosphohydrolases; C579846:NRAS protein, human