Missing content? – Request curation!
Request curation for specific Genes, Variants, or PubMed publications.
Have questions, comments, or suggestions? - Let us know!
Email us at : ckbsupport@genomenon.com
Ref Type | Journal Article | ||||||||||||
PMID | (29880583) | ||||||||||||
Authors | Wang J, Yao Z, Jonsson P, Allen AN, Qin ACR, Uddin S, Dunkel IJ, Petriccione M, Manova K, Haque S, Rosenblum MK, Pisapia DJ, Rosen N, Taylor BS, Pratilas CA | ||||||||||||
Title | A Secondary Mutation in BRAF Confers Resistance to RAF Inhibition in a BRAFV600E-Mutant Brain Tumor. | ||||||||||||
|
|||||||||||||
URL | |||||||||||||
Abstract Text | BRAFV600E hyperactivates ERK and signals as a RAF inhibitor-sensitive monomer. Although RAF inhibitors can produce impressive clinical responses in patients with mutant BRAF tumors, the mechanisms of resistance to these drugs are incompletely characterized. Here, we report a complete response followed by clinical progression in a patient with a BRAFV600E-mutant brain tumor treated with dabrafenib. Whole-exome sequencing revealed a secondary BRAFL514V mutation at progression that was not present in the pretreatment tumor. Expressing BRAFV600E/L514V induces ERK signaling, promotes RAF dimer formation, and is sufficient to confer resistance to dabrafenib. Newer RAF dimer inhibitors and an ERK inhibitor are effective against BRAFL514V-mediated resistance. Collectively, our results validate a novel biochemical mechanism of RAF inhibitor resistance mediated by a secondary mutation, emphasizing that, like driver mutations in cancer, the spectrum of mutations that drive resistance to targeted therapy are heterogeneous and perhaps emerge with a lineage-specific prevalence.Significance: In contrast to receptor tyrosine kinases, in which secondary mutations are often responsible for acquired resistance, second-site mutations in BRAF have not been validated in clinically acquired resistance to RAF inhibitors. We demonstrate a secondary mutation in BRAF (V600E/L514V) following progression on dabrafenib and confirm functionally that this mutation is responsible for resistance. Cancer Discov; 8(9); 1130-41. ©2018 AACR.See related commentary by Romano and Kwong, p. 1064This article is highlighted in the In This Issue feature, p. 1047. |
Molecular Profile | Treatment Approach |
---|
Gene Name | Source | Synonyms | Protein Domains | Gene Description | Gene Role |
---|
Drug Name | Trade Name | Synonyms | Drug Classes | Drug Description |
---|---|---|---|---|
BGB3245 | BGB-3245|BGB 3245 | RAF Inhibitor (Pan) 28 | BGB3245 inhibits RAF dimer formation, which may lead to inhibition of Erk signaling and cell growth (PMID: 29880583). | |
BGB3290 | BGB-3290|BGB 3290 | BGB3290 inhibits RAF dimer formation, which may lead to inhibition of Erk signaling and cell growth (PMID: 29880583). |
Gene | Variant | Impact | Protein Effect | Variant Description | Associated with drug Resistance |
---|---|---|---|---|---|
BRAF | L514V | missense | gain of function - predicted | BRAF L514V lies within the protein kinase domain of the Braf protein (UniProt.org). L514V is predicted to lead to a gain of Braf function as indicated by moderate increase of Mek and Erk phosphorylation in culture, enhanced dimerization when expressed in cis with BRAF V600E, and is associated with resistance to Raf inhibitors (PMID: 29880583). | Y |
Molecular Profile | Indication/Tumor Type | Response Type | Therapy Name | Approval Status | Evidence Type | Efficacy Evidence | References |
---|---|---|---|---|---|---|---|
BRAF L514V BRAF V600E | melanoma | decreased response | Vemurafenib | Preclinical - Cell culture | Actionable | In a preclinical study, melanoma cells expressing BRAF L514V in cis with V600E demonstrated decreased response to Zelboraf (vemurafenib)-induced inhibition of Erk phosphorylation and colony formation compared to cells expressing BRAF V600E in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | decreased response | Trametinib | Preclinical - Cell culture | Actionable | In a preclinical study, melanoma cells expressing BRAF L514V in cis with V600E demonstrated decreased response to Mekinist (trametinib)-induced inhibition of Erk phosphorylation and colony formation compared to cells expressing BRAF V600E in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | decreased response | TAK-632 | Preclinical - Cell culture | Actionable | In a preclinical study, melanoma cells expressing BRAF L514V in cis with V600E demonstrated decreased response to TAK-632-induced inhibition of Erk phosphorylation and colony formation compared to cells expressing BRAF V600E in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | decreased response | Dabrafenib | Preclinical - Cell culture | Actionable | In a preclinical study, melanoma cells expressing BRAF L514V in cis with V600E demonstrated decreased response to Tafinlar (dabrafenib)-induced inhibition of Erk phosphorylation and colony formation compared to cells expressing BRAF V600E in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | predicted - sensitive | SCH772984 | Preclinical - Cell culture | Actionable | In a preclinical study, SCH772984 resulted in similar inhibition of Erk phosphorylation and colony formation in melanoma cells expressing BRAF L514V in cis with V600E and cells expressing BRAF V600E alone in culture (PMID: 29880583). | 29880583 |
BRAF L514V | breast cancer | resistant | Dabrafenib | Preclinical - Cell culture | Actionable | In a preclinical study, Tafinlar (dabrafenib) did not inhibit Erk and Mek signaling in breast cancer cells expressing BRAF L514V in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | decreased response | PLX8394 | Preclinical - Cell culture | Actionable | In a preclinical study, melanoma cells expressing BRAF L514V in cis with V600E demonstrated decreased response to PLX8394-induced inhibition of Erk phosphorylation and colony formation compared to cells expressing BRAF V600E in culture (PMID: 29880583). | 29880583 |
BRAF V600E | ganglioglioma | predicted - sensitive | Dabrafenib | Case Reports/Case Series | Actionable | In a clinical case study, Tafinlar (dabrafenib) treatment resulted in partial response 8 weeks after therapy initiation in a pediatric patient with anaplastic ganglioglioma harboring BRAF V600E, but disease progression occurred at 40 weeks due to acquired resistance (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | predicted - sensitive | BGB3245 | Preclinical - Cell culture | Actionable | In a preclinical study, BGB3245 resulted in similar inhibition of Erk phosphorylation and colony formation in melanoma cells expressing BRAF L514V in cis with V600E and cells expressing BRAF V600E alone in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | melanoma | predicted - sensitive | BGB3290 | Preclinical - Cell culture | Actionable | In a preclinical study, BGB3290 resulted in similar inhibition of Erk phosphorylation and colony formation in melanoma cells expressing BRAF L514V in cis with V600E and cells expressing BRAF V600E alone in culture (PMID: 29880583). | 29880583 |
BRAF L514V BRAF V600E | ganglioglioma | resistant | Dabrafenib | Case Reports/Case Series | Actionable | In a clinical case study, a pediatric patient with anaplastic ganglioglioma harboring BRAF V600E progressed after initial response to Tafinlar (dabrafenib) treatment, and was found to have acquired a BRAF L514V in cis with BRAF V600E, which conferred dabrafenib resistance in culture (PMID: 29880583). | 29880583 |