None of the 195 patients with other peripheral B-cell lymphomas or leukemias who were evaluated carried the BRAFV600E variant, including 38 patients with splenic marginal-zone lymphomas or unclassifiable splenic lymphomas or leukemias.
The ERK1/2 (extracellular signal-regulated kinase 1 and 2) pathway, comprising the protein kinases RAF (v-raf-1 murine leukemia viral oncogene homolog 1), MEK1/2 (mitogen-activated protein kinase or ERK kinase 1 and 2) and ERK1/2 is frequently de-regulated in human cancers, due to mutations in RAS or BRAF (v-raf-1 murine leukemia viral oncogene homolog B1).
The BRAF kinase is mutated, typically Val 600→Glu (V600E), to induce an active oncogenic state in a large fraction of melanomas, thyroid cancers, hairy cell leukaemias and, to a smaller extent, a wide spectrum of other cancers.
Characterization of a patient with concurrent BRAF-mutant melanoma and NRAS-mutant leukemia treated intermittently with combined BRAF and MEK inhibition provides new insights into the potential clinical and molecular effects of this therapeutic strategy.