t(1;14)(q21;q32) MUC1/IGH

2005-01-01   Jacques Boyer 

1.Laboratoire d hématologie, CH du MANS, France

Clinics and Pathology

Noted

The chromosomal band 1q21 is the third most frequent site of rearrangement in non-Hodgkins lymphoma after 14q32 and 18q21.
Five genes mapped to this region (BCL9, MUC1, FCGR2B, MUM2, API2) some have been shown to be deregulated by juxtaposition with the IgH genes.

Disease

B-cell non Hodgkin Lymphoma (NHL)

Epidemiology

The MUC1 region is rearranged in 6% of tumors with 1q21 cytogenetic aberration.

Cytology

No clear association with a particular NHL subtype has been reported.

Prognosis

Poor prognosis especially in diffuse large cell lymphoma.
May be associated with tumor progression.

Cytogenetics

Cytogenetics morphological

A number of 1q21 abnormalities result in an unbalanced chromosome 1 translocation.

Additional anomalies

Caryotype often complex.
Usually detected with t(14;18)(q32;q21) and t(8;14)(q24;q32) as a secondary chromosomal abnormalitie.

Genes Involved and Proteins

Gene name
MUC1 (mucin 1, cell surface associated)
Location
1q22
Note
Located 8cM telomeric to BCL9; aliases of MUC1 are EMA and CD227.
Dna rna description
3.88 kb, 8 exons, 1721 bp, 2 transcripts.
Protein description
122.1 kDa (1255 aa) Highly glycosylated protein.
The MUC1 protein can be expressed as a transmembrane or secreted protein.
May be playing a role in adhesive functions and in cell-cell interactions, metastasis, signaling and is implicated in some adenocarcinomas.
The EMA wich is equivalent to MUC1 occurs in lymphocyte-predominant Hodgkins disease, plasmocytomas and T-cell lymphomas due to mechanisms other than 1q21 rearrangement.
Gene name
IGH (Immunoglobulin Heavy)
Location
14q32.33

Result of the Chromosomal Anomaly

Description

The translocation links sequences 2.4 kpb 3 of the MUC1 gene on chromosome 1 to the IGH4 switch region on chromosome 14. MUC1 gene is intact. The MUC1 gene is brought into proximity with the C gamma 4 and C alpha 2 loci. Downstream of C alpha 2 is an enhancer element implicated in the activation of MUC1 expression.No fusion protein.

Oncogenesis

Chromosomal translocation involving class switch recombination when DNA strand breaks are introduced into the switch regions of recombining CH genes. Activation of MUC1 translation and transcription. An important role for MUC1 in tumorigenesis has been demontrated in Muc-1 null mice. MUC1 is associated with delayed progression of the tumor (selective advantage, inhibition of cell adhesion).
In addition to activation of MUC1, haploid loss of chromosome 1 long arm also contributes to oncogenesis in some tumors.

Bibliography

Pubmed IDLast YearTitleAuthors
107538492000MUC1 is activated in a B-cell lymphoma by the t(1;14)(q21;q32) translocation and is rearranged and amplified in B-cell lymphoma subsets.Dyomin VG et al
107794412000MUC1 dysregulation as the consequence of a t(1;14)(q21;q32) translocation in an extranodal lymphoma.Gilles F et al
117015422000Non-Hodgkin's Lymphoma: Molecular Features of B Cell Lymphoma.Macintyre E et al

Citation

Jacques Boyer

t(1;14)(q21;q32) MUC1/IGH

Atlas Genet Cytogenet Oncol Haematol. 2005-01-01

Online version: http://atlasgeneticsoncology.org/haematological/1342/t(1;14)(q21;q32)

External Links