A new breakpoint, telomeric to TEL/ETV6, on the short arm of chromosome 12 in T cell acute lymphoblastic leukemia

Abstract

Abnormalities of the short arm of chromosome 12 frequently December. The child was then treated according to the protoinvolve the TEL/ETV6 gene in acute leukemias. In two cases of col FRALLE 93, and a bone marrow autograft was carried out T cell acute lymphoblastic leukemia with translocation in May 1996. A relapse occurred in June 1996 with liver t(12;14)(p13;q11) and t(7;12)(q35;p13), respectively, the breakenlargement, high WBC at 120 × 10 9 /l with 90% blast cells. peripheral blood, 277 × 10 9 /l leukocytes with 84% blast cells,

Deregulation of cyclin D2 by juxtaposition with T‐cell receptor alpha/delta locus in t(12;14)(p13;q11)‐positive childhood T‐cell acute lymphoblastic leukemia

“…The analyses also included a probe for IGH@ (14q32). In case 2, as previously reported, the YAC 27BE8 showed a signal on the normal 14 and on the der (12), indicating a BP centromeric to this probe (arrow) (5). (C) In case 1, the BP on 12p13 was mapped using 11 BAC probes.…”

“…The clinical features of this patient have previously been reported by Le Coniat et al (5) as case 1. In brief, a 1‐year‐old boy was admitted due to acute leukemia to Saint Louis Hospital, Paris in September 1995.…”

“…Until very recently, CCND2 at 12p13 had not been shown to be involved in chromosomal abnormalities in T‐ALL. We hypothesized that the t(12;14)(p13;q11) – a translocation occurring in approximately 1% of cytogenetically abnormal childhood T‐ALLs (2, 4–9) – could affect the expression of CCND2 through juxtaposition with the TCR loci at 14q11. Indeed, while this manuscript was being prepared for submission, Clappier et al (9) reported a real‐time polymerase chain reaction (PCR) screening of T‐ALLs, identifying three cases with CCND2 overexpression and 12p13 rearrangements, one of which a t(12;14).…”

Characterization of 12p molecular events outside ETV6 in complex karyotypes of acute myeloid malignancies

“…Breakpoints on 12p outside ETV6 have been identified in both myeloid and lymphoid diseases (Sato et al , 1997; Le Coniat et al , 1997; Aguiar et al , 1997; Tosi et al , 1997; La Starza et al , 1998; Salomon‐Nguyen et al , 1998; Streubel et al , 1998; Andreasson et al , 1998). However, the molecular boundaries of such changes are still undetermined.…”

Cyclin D2 dysregulation by chromosomal translocations to TCR loci in T-cell acute lymphoblastic leukemias

“…Of note, such chromosomal translocations had been rarely but recurrently reported in T-ALL, but target genes were unresolved (see Mitelman Database of Chromosome Aberrations in Cancer, http://cgap.nci.nih.gov/Chromosomes/ Mitelman). [22][23][24] The TEL1/ETV6 and KIP1/CDKN1B genes, located more than 8 Mb centromeric to the CCND2 locus, have been previously involved in various 12p13.2 genomic rearrangements in leukemia, including the t(7;12)(q36;p13) in infant. [25][26][27][28] We analyzed the TEL1/ETV6 and KIP1/CDKN1B loci by FISH in our three T-ALL cases, and did not detect any abnormalities (data not shown).…”