Simple genetic diagnosis of hairy cell leukemia by sensitive detection of the BRAF-V600E mutation.
Hairy cell leukemia (HCL) is a distinct clinicopathologic entity that responds well to purine analogs but is sometimes difficult to differentiate from HCL-like disorders (e.g., splenic marginal zone lymphoma and HCL variant). We recently identified the BRAF-V600E mutation as the disease-defining genetic event in HCL. In this study, we describe a new, simple, and inexpensive test for genetics-based diagnosis of HCL in whole-blood samples that detects BRAF-V600E through a sensitive allele-specific PCR qualitative assay followed by agarose-gel electrophoresis. This approach detected BRAF-V600E in all 123 leukemic HCL samples investigated containing as few as 0.1% leukemic cells. BRAF-V600E was detected at different time points during the disease course, even after therapy, pointing to its pivotal role in HCL pathogenesis and maintenance of the leukemic clone. Conversely, 115 non-HCL chronic B-cell neoplasms, including 79 HCL-like disorders, were invariably negative for BRAF-V600E. This molecular assay is a powerful tool for improving the diagnostic accuracy in HCL.
Institute of Hematology, University of Perugia, Perugia, Italy. etiacci@solido.umbria.it
Enrico
E
Tiacci
Gianluca
G
Schiavoni
Francesco
F
Forconi
Alessia
A
Santi
Livio
L
Trentin
Achille
A
Ambrosetti
Debora
D
Cecchini
Elisa
E
Sozzi
Paola
P
Francia di Celle
Cristiana
C
Di Bello
Alessandro
A
Pulsoni
Robin
R
Foà
Giorgio
G
Inghirami
Brunangelo
B
Falini
D016022:Case-Control Studies; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000097:blood / Q000235:genetics; D005434:Flow Cytometry; D006801:Humans; D015448:Leukemia, B-Cell / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D007943:Leukemia, Hairy Cell / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D016393:Lymphoma, B-Cell / Q000097:blood / Q000175:diagnosis* / Q000235:genetics; D017354:Point Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction; D048493:Proto-Oncogene Proteins B-raf / Q000097:blood / Q000235:genetics*
D004273:DNA, Neoplasm; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf