A BCR-JAK2 fusion gene as the result of a t(9;22)(p24;q11.2) translocation in a patient with a clinically typical chronic myeloid leukemia.
Chronic myeloid leukemia (CML) is characterized by the presence of a t(9;22)(q34;q11.2), which leads to the well-known BCR-ABL1 fusion protein. We describe a patient who was diagnosed clinically with a typical CML but on cytogenetic analysis was found to have a t(9;22)(p24;q11.2). Chromosomal fluorescence in situ hybridization showed that the BCR gene locus spanned the breakpoint at band 22q11.2 but that the ABL1 gene was not rearranged. By means of a candidate gene approach, the JAK2 gene, at 9p24, was identified as the fusion partner of BCR in this case. The BCR-JAK2 fusion protein contains the coiled-coil dimerization domain of BCR and the protein tyrosine kinase domain (JH1) of JAK2. The patient's disease did not respond to Imatinib, and this unresponsiveness was most likely a result of the BCR-JAK2 fusion protein.
Department of Hematology and Oncology, University of Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany. fgriesi@med.uni-goettingen.de
Frank
F
Griesinger
Heike
H
Hennig
Frauke
F
Hillmer
Martina
M
Podleschny
Rainer
R
Steffens
Andreas
A
Pies
Bernhard
B
Wörmann
Detlef
D
Haase
Stefan K
SK
Bohlander
D000970:Antineoplastic Agents / Q000627:therapeutic use; D001549:Benzamides; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D017404:In Situ Hybridization, Fluorescence; D053614:Janus Kinase 2; D007621:Karyotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy / Q000235:genetics*; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D010879:Piperazines / Q000627:therapeutic use; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D051562:Proto-Oncogene Proteins c-bcr / Q000235:genetics*; D011743:Pyrimidines / Q000627:therapeutic use; D014178:Translocation, Genetic / Q000235:genetics*
D000970:Antineoplastic Agents; D001549:Benzamides; D015514:Oncogene Proteins, Fusion; D010879:Piperazines; D011518:Proto-Oncogene Proteins; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; D053614:Janus Kinase 2; C496613:BCR protein, human; D051562:Proto-Oncogene Proteins c-bcr