t(1;14)(q25;q32) IGH/LHX4

2005-03-01   Jacques Boyer  

1.Laboratoire d hématologie, CH du MANS, France

Clinics and Pathology

Disease

Only two cases : Case 1: acute pre-B lymphoblastic leukemia (ALL); case 2: biphenotypic blast crisis of a chronic myelogenous leukemia(CML)

Epidemiology

rare

Clinics

Case 1: A 53-year-old woman with ALL; case 2: A 52-year-old in CML blast crisis

Cytogenetics

Cytogenetics morphological

dup(1)(q21-25) is frequently detected in ALL of B-cell lineage

Additional anomalies

case 1: associated with t(9;22)(q23 ?;q11) : the breakpoint at 9q23 reported in this paper needs to be confirmed; case 2: 46,XY,t(9;22)(q34;q11)/46, XY,t(1;14(q25;q32), del(20)(q11;q13.3) / 46,XY, t(1;14)(q25;q32) , add(19)(p13).

Genes Involved and Proteins

Gene name
LHX4 (LIM homeobox 4)
Location
1q25.2
Note
Alias : Gsh-4. LHX4 gene is a member of the LIM-homeobox gene.
Dna rna description
DNA : 44,66 kb and 6 exons. RNA : 1913 bp
Protein description
LHX4 protein (40,8kDa, 390 aa) is very close to LHX3.The human LHX4 includes one tandem pair of zinc-finger LIM motifs and one adjacent homeodomain.
Gene name
IGH (Immunoglobulin Heavy)
Location
14q32.33

Result of the Chromosomal Anomaly

Description

case 1: the enhancer region of the IgH gene is fused to the 5¹ regulatory region of the Lhx4 gene in a head-to-head configuration. LHX4 mRNA is expressed at high levels; case 2: the breakpoint fuses the J4 segment of IgH to sequences located 16kb from LHX4 Exon 1 in a head-to-head configuration. LHX4 mRNA is expressed at high levels.

Note

No fusion protein

Oncogenesis

LHX4 homeodomain could play an important role as transcriptional regulators in cell regulation, but there is no report about the impairment of hematopoiesis in LHX4 deficient mice and human. There is no report about the transformation activity in the LHX4 gene. Overexpression of LXH2 has been reported in chronic myeloid leukemias and ALL.

Article Bibliography

Pubmed IDLast YearTitleAuthors
121183772002A novel chromosomal translocation t(1;14)(q25;q32) in pre-B acute lymphoblastic leukemia involves the LIM homeodomain protein gene, Lhx4.Kawamata N et al
145067032003Aberrant expression of the LHX4 LIM-homeobox gene caused by t(1;14)(q25;q32) in chronic myelogenous leukemia in biphenotypic blast crisis.Yamaguchi M et al

Summary

Fusion gene

IGH/LHX4 IGH (14q32.33) LHX4 (1q25.2) M t(1;14)(q25;q32)

Note

Chromosome band 1q21-25 is one of the hotspots of chromosomal abnormalities in hematological malignancy. LHX4 gene at 1q25 is a novel gene coding for LIM proteins.

Citation

Jacques Boyer

t(1;14)(q25;q32) IGH/LHX4

Atlas Genet Cytogenet Oncol Haematol. 2005-03-01

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