Blood, Vol. 95 No. 8 (April 15), 2000:
pp. 2719-2721
BRIEF REPORT
The Ikaros gene, a central regulator of lymphoid
differentiation, fuses to the BCL6 gene as a result of
t(3;7)(q27;p12) translocation in a patient with diffuse large
B-cell lymphoma
Yoshitaka Hosokawa,
Yumiko Maeda,
Ryo Ichinohasama,
Ikuo Miura,
Masafumi Taniwaki, and
Masao Seto
From the Laboratory of Molecular Medicine, Aichi Cancer Center
Research Institute, Nagoya; Department of Oral Pathology, Tohoku
University School of Dentistry, Sendai; Third Department of Internal
Medicine, Akita University School of Medicine, Akita; and Third
Department of Internal Medicine, Kyoto Prefectural University of
Medicine, Kyoto, Japan.
The BCL6 gene, isolated from the breakpoints of
3q27-associated chromosomal translocations, has been implicated in
diffuse large B-cell lymphomas (DLBL). Here we describe the molecular characterization of novel t(3;7)(q27;p12) translocations in 2 patients
with DLBL. Molecular genetic analysis of the breakpoint area involving
BCL6 revealed the presence of the Ikaros gene, a central
regulator of lymphoid differentiation that had been mapped to human
chromosome 7 band p13-p11.1. As a molecular consequence of the
translocation, the 5' regulatory region of the BCL6 gene was replaced by the putative 5' regulatory region of the
Ikaros gene, probably leading to deregulated expression of the
BCL6 gene throughout B-cell differentiation. Reverse
transcription-polymerase chain reaction (RT-PCR) and fluorescence in
situ hybridization (FISH) analyses of a patient sample established that
the t(3;7)(q27;p12) results in fusion of the Ikaros and
BCL6 genes. This study provides the first evidence that
the Ikaros gene is rearranged in human hematopoietic
malignant disorders.
