(11; 14) Translocation in three boys with acute lymphoblastic leukemia of T-cell immunophenotype

Abstract

Three boys, 12, 15 and 5 years old are presented with acute lymphoblastic leukemia resp. Non-Hodgkin's lymphoma with leukemic transformation. Blast cells could be characterized as being of T-cell origin. Hand mirror variant was the predominant morphologic feature of the blast cells in two patients. Chromosome analysis of the leukemic blast cells revealed a pseudodiploid (modal chromosome number = 46) karyotype in two patients and a pseudotetraploid (modal chromosome number = 92) in one patient. A chromosome translocation (11; 14) with breakpoints at (p 13; q 13) (within the human T-cell receptor alpha chain locus!) was found in the leukemic cells of all three cases plus an additional t (7; 9) (q 22; p 13) in one patient.

The mechanism of chromosomal translocation t(11;14) involving the T-cell receptor C delta locus on human chromosome 14q11 and a transcribed region of chromosome 11p15.

“…Interestingly, the majority of these tumours have translocations or inversions involving the T-cell receptor a locus (TCRa) at chromosome band 14q1 1. These fall into two groups; one group having breakpoints at lp 13 (Harbott et al, 1986;Williams et al, 1984;White et al, 1984) and the other at I p 15 (Le Takasaki et al, 1987) [t(11;14) (p13;ql 1) and t(l 1; 14) (p5;ql 1) respectively]. Recently, a new locus has been studied in T-cell tumours carrying inversion of chromosome 14 inv(14) (ql 1 ;q32) or translocation t(14; 14) (qI 1; 132) (Mengle-Gaw et al, 1987).…”

An (8;14)(q24;q11) translocation involving the T‐cell receptor α‐chain gene and the MYC oncogene 3′ region in a B‐cell lymphoma

“…T-cell neoplasms are frequently associated with rearrangements involving chromosome 14 band q l l , the region to which the T-cell receptor &-chain gene (TCRA) has been mapped (Caccia et al, 1985;Croce et al, 1985). The recurring abnormalities associated with this band include the paracentric inversion inv( 14)(ql lq32) (Ueshima et al, 1984;Zech et al, 1984;Baer et al, 1985Baer et al, , 1987Denny et al, 1986), a closely related t( 14; 14)(ql l;q32) (Kaiser-McCaw et al, 1975;Aurias, 1981;Mengle-Gaw et al, 1987), t(ll;l4)(pl5;qll) Boehm et al, 1988), t ( l l ; l 4 ) ( p l 3 ; q l l ) (Williams et al, 1984;Harbott et al, 1986), and t(8;14)(q24;qll). We as well as others have previously characterized the t(8; 14)(q24;qll) translocation and have shown that the MYC protooncogene is juxtaposed with a segment of the TCRA gene (Erikson et al, 1986;Mathieu-Mahul et al, 1986;McKeithan et al, 1986;Shima et al, 1986).…”