Chromosome translocations involving band 7q35 or 7p15 in childhood T- cell
leukemia/lymphoma
Y Kaneko, N Maseki, C Homma, M Sakurai, S Mizutani, T Takeda, T Shikano, T Fujimoto, K Yaoi and T Shimokawa
Department of Laboratory Medicine, Saitama Cancer Center, Japan.
In a chromosome study in childhood T-cell leukemia/lymphoma, we found
t(7;11)(q35;p13) in 2 patients, t(7;14) (q35;q11) in one patient, and
t(7;14)(p15;q32) in 1 patient. Southern blotting and in situ chromosomal
hybridization studies in one patient with the t(7;11) demonstrated that
both alleles of the T-cell antigen receptor beta- subunit gene (TCRB) were
rearranged, and that one TCRB allele had relocated from 7q35 to the fusion
point in band p13 of the involved chromosome 11 (11p-). These findings
suggest that juxtaposition of TCRB with the putative oncogene tcl-2 located
in band 11p13 may be a critical step toward development of this T-cell
leukemia/lymphoma. In the other two translocations, all breakpoints were
sites for lymphocyte function genes, ie, 7q35 for TCRB, 14q11 for T-cell
antigen receptor alpha-subunit gene (TCRA), 7p15 for T-cell antigen
receptor alpha- subunit gene (TCRG), and 14q32 for immunoglobulin
heavy-chain gene (IGH). Thus, the findings in these cases allow us to
expand the above hypothesis and propose that the juxtaposition of TCRB or
TCRG with tcl- 2, TCRA, or IGH through chromosomal translocation may
activate a mechanism for the genesis of T-cell leukemia/lymphoma with these
chromosome translocations.
Volume 72,
Issue 2,
pp. 534-538,
08/01/1988
Copyright © 1988 by The American Society of Hematology
