Abnormalities at 14q32.1 in T cell malignancies involve two oncogenes

Abnormalities at 14q32.1 in T cell malignancies involve two oncogenes

^*Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107; ^†Toyama University, 3190 Gofuku, Toyama City 930-8555 Japan; and ^‡Istituto Dermopatico dell’ Immacolata-IRCCS, Via dei Monti di Creta 104, 00167 Rome, Italy

Contributed by Carlo M. Croce

Abstract

The TCL1 oncogene on human chromosome 14q32.1 is involved in the development of T cell leukemia in humans. Its expression in these leukemias is activated by chromosomal translocations and inversions at 14q32.1. Here we report the isolation and characterization of a new member of the TCL1 gene family, TCL1b, located ≈16 kb centromeric of TCL1. The 1.2-kb TCL1b cDNA encodes a 14-kDa protein of 128 aa and shows 60% similarity to Tcl1. Expression profiles of TCL1 and TCL1b genes are very similar: both genes are expressed at very low levels in normal bone marrow and peripheral lymphocytes but are activated in T cell leukemia by rearrangements of the 14q32.1 region. Thus, translocations and inversions at 14q32.1 in T cell malignancies involve two oncogenes.

Footnotes

↵ § To whom reprint requests should be addressed at: Kimmel Cancer Center, Thomas Jefferson University, BLSB Room 1050, 233 South 10th Street, Philadelphia, PA 19107. e-mail: croce{at}calvin.jci.tju.edu.
Data deposition: The sequences reported in this paper have been deposited in the GenBank database [accession nos. AF110465 (TCL1b gene), AF110466 (TCL1b cDNA), and AF110467 (TCL1b pseudogene)].
ABBREVIATIONS:

RACE,

rapid amplification of cDNA ends;

RT-PCR,

reverse transcription–PCR;

EBV,

Epstein–Barr virus