Validation of an interphase fluorescence in situ hybridization approach for the detection of MLL gene rearrangements and of the MLL/AF9 fusion in acute myeloid leukemia.
To validate a 2-step FISH assay for the identification of the t(9;11)(p22;q23), 96 acute myeloid leukemias were studied by cytogenetic analysis, FISH and molecular biology. After a first FISH step using an MLL probe, 24/27 cases with 11q23 break showed MLL rearrangement. Southern blotting confirmed FISH data. In the second step, 24 cases with MLL rearrangement were studied using MLL and AF9 probes: 17/18 cases with t(9;11) showed MLL/AF9 fusion. In 6 patients with 11q23/MLL rearrangements other than t(9;11), FISH confirmed MLL involvement and excluded AF9 involvement. This is a reliable method for the identification of MLL/AF9 fusion in interphase cells, allowing for a reclassification of cases with suboptimal chromosome morphology. The frequency of deletion surrounding MLL and AF9 breakpoint is low.
Cavazzini
Francesco
F
Dipartimento di Scienze Biomediche e Terapie Avanzate, Sezione di Ematologia, University of Ferrara, Italy.
Bardi
Antonella
A
Tammiso
Elisa
E
Ciccone
Maria
M
Russo-Rossi
Antonella
A
Divona
Domenica
D
Lo Coco
Francesco
F
Hernandez
Jesus Maria
JM
Wlodarska
Iwona
I
Hagemeijer
Anne
A
Castoldi
Gianluigi
G
Cuneo
Antonio
A
D015321:Gene Rearrangement / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods* / Q000592:standards; D007399:Interphase / Q000235:genetics*; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D051788:Myeloid-Lymphoid Leukemia Protein / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*; D015514:Oncogene Proteins, Fusion / Q000235:genetics*
C474558:MLL-AF9 fusion protein, human; C489901:MLLT3 protein, human; D009687:Nuclear Proteins; D015514:Oncogene Proteins, Fusion; D051788:Myeloid-Lymphoid Leukemia Protein