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Cancer Discov DOI:10.1158/2159-8290.CD-12-0470

A genome-scale RNA interference screen implicates NF1 loss in resistance to RAF inhibition.

Publication TypeJournal Article
Year of Publication2013
AuthorsWhittaker, SR, Theurillat, J-P, Van Allen, E, Wagle, N, Hsiao, J, Cowley, GS, Schadendorf, D, Root, DE, Garraway, LA
JournalCancer Discov
Date Published2013 Mar
KeywordsCell Line, Tumor, Cell Proliferation, Drug Resistance, Neoplasm, Humans, MAP Kinase Signaling System, Melanoma, Mutation, Neurofibromin 1, Protein Kinase Inhibitors, Proto-Oncogene Proteins B-raf, RNA Interference

RAF inhibitors such as vemurafenib and dabrafenib block BRAF-mediated cell proliferation and achieve meaningful clinical benefit in the vast majority of patients with BRAF(V600E)-mutant melanoma. However, some patients do not respond to this regimen, and nearly all progress to therapeutic resistance. We used a pooled RNA interference screen targeting more than 16,500 genes to discover loss-of-function events that could drive resistance to RAF inhibition. The highest ranking gene was NF1, which encodes neurofibromin, a tumor suppressor that inhibits RAS activity. NF1 loss mediates resistance to RAF and mitogen-activated protein kinase (MAPK) kinase kinase (MEK) inhibitors through sustained MAPK pathway activation. However, cells lacking NF1 retained sensitivity to the irreversible RAF inhibitor AZ628 and an ERK inhibitor. NF1 mutations were observed in BRAF-mutant tumor cells that are intrinsically resistant to RAF inhibition and in melanoma tumors obtained from patients exhibiting resistance to vemurafenib, thus showing the clinical potential for NF1-driven resistance to RAF/MEK-targeted therapies.


Alternate JournalCancer Discov
PubMed ID23288408
PubMed Central IDPMC3606893
Grant List5P50CA127003-05 / CA / NCI NIH HHS / United States
P50 CA093683 / CA / NCI NIH HHS / United States
T32 CA009172 / CA / NCI NIH HHS / United States
DP2OD002750 / OD / NIH HHS / United States
DP2 OD002750 / OD / NIH HHS / United States
R33 CA155554 / CA / NCI NIH HHS / United States
U54 CA112962 / CA / NCI NIH HHS / United States
P50 CA127003 / CA / NCI NIH HHS / United States