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Progression of RAS-mutant leukemia during RAF inhibitor treatment.

ABSTRACT: Vemurafenib, a selective RAF inhibitor, extends survival among patients with BRAF V600E-mutant melanoma. Vemurafenib inhibits ERK signaling in BRAF V600E-mutant cells but activates ERK signaling in BRAF wild-type cells. This paradoxical activation of ERK signaling is the mechanistic basis for the development of RAS-mutant squamous-cell skin cancers in patients treated with RAF inhibitors. We report the accelerated growth of a previously unsuspected RAS-mutant leukemia in a patient with melanoma who was receiving vemurafenib. Exposure to vemurafenib induced hyperactivation of ERK signaling and proliferation of the leukemic cell population, an effect that was reversed on drug withdrawal.

SUBMITTER: Callahan MK

PROVIDER: S-EPMC3627494 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Progression of RAS-mutant leukemia during RAF inhibitor treatment.

Callahan Margaret K MK Rampal Raajit R Harding James J JJ Klimek Virginia M VM Chung Young Rock YR Merghoub Taha T Wolchok Jedd D JD Solit David B DB Rosen Neal N Abdel-Wahab Omar O Levine Ross L RL Chapman Paul B PB

The New England journal of medicine 20121107 24

Vemurafenib, a selective RAF inhibitor, extends survival among patients with BRAF V600E-mutant melanoma. Vemurafenib inhibits ERK signaling in BRAF V600E-mutant cells but activates ERK signaling in BRAF wild-type cells. This paradoxical activation of ERK signaling is the mechanistic basis for the development of RAS-mutant squamous-cell skin cancers in patients treated with RAF inhibitors. We report the accelerated growth of a previously unsuspected RAS-mutant leukemia in a patient with melanoma ...[more]

PMID: 23134356

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