t(X;2)(q11;p23) MSN/ALK

2001-08-01   Jean-Loup Huret 

1.Genetics, Dept Medical Information, University of Poitiers, CHU Poitiers Hospital, F-86021 Poitiers, France

Clinics and Pathology

Disease

  • Translocations involving 2p23 are found in more than half cases of anaplasic large cell lymphoma (ALCL), a high grade non Hodgkin lymphoma (NHL). They involve ALK, and are therefore called ALK+ ALCL.
  • The most frequent ALK+ ALCL being the the t(2;5)(p23;q35) with NPM1 -ALK fusion protein, which localises both in the cytoplasm and in the nucleus.
  • In translocations other than the t(2;5), i.e. in t(2;Var) involving various partners and ALK, the fusion protein has a cytoplasmic localization; they are therefore called "cytoplasm only" ALK+ ALCL. However, in case of a t(X;2) the localization is restricted to the membrane.The t(X;22)(q11;p23) is very rare.
  • Phenotype stem cell origin

    CD30+; ALK+

    Clinics

    only 1 case to date: a 18 yr old man

    Prognosis

    unknown: the patient achieved remission, but died of an unrelated cause

    Genes Involved and Proteins

    Gene name
    MSN (moesin)
    Location
    Xq12
    Protein description
    576 amino acids, 75 kDa; cytoskeleton protein; binds to the plasma membrane and interacts with actin.
    Gene name
    ALK (anaplastic lymphoma receptor tyrosine kinase)
    Location
    2p23.2
    Protein description
    1620 amino acids; 177 kDa; glycoprotein (200 kDa mature protein) ; membrane associated tyrosine kinase receptor

    Result of the Chromosomal Anomaly

    Description

    5 MSN - 3 ALK. The breakpoint in ALK is different (17 bp downstream) from that observed in NPM1-ALK and other hybrid genes.1005 amino acids, 125 kDa; 448 N-term amino acid from MSN, containing the band 4.1 like domain and most of the alpha helix domain, fused to the 557 (instead of the usual 562) C-term amino acids from ALK (i.e. the cytoplasmic portion of ALK with the tyrosine kinase domain).

    Expression localisation

    membrane restricted, in contrast with the t(2;5)(p23;q35) with NPM1-ALK, which localizes both in the cytoplasm and in the nucleus, and with other "variant ALK+" which have a cytoplasmic localisation.

    Oncogenesis

    tyrosine kinase activity.

    Highly cited references

    Pubmed IDYearTitleCitations
    121125242002Identification of novel fusion partners of ALK, the anaplastic lymphoma kinase, in anaplastic large-cell lymphoma and inflammatory myofibroblastic tumor.65
    128001562003Non-muscle myosin heavy chain (MYH9): a new partner fused to ALK in anaplastic large cell lymphoma.29
    113108342001Molecular characterization of a new ALK translocation involving moesin (MSN-ALK) in anaplastic large cell lymphoma.26
    152979722004Heterogeneity of genomic breakpoints in MSN-ALK translocations in anaplastic large cell lymphoma.9

    Bibliography

    Pubmed IDLast YearTitleAuthors
    109949992000Pathobiology of NPM-ALK and variant fusion genes in anaplastic large cell lymphoma and other lymphomas.Drexler HG et al
    113803912001Alk+ CD30+ lymphomas: a distinct molecular genetic subtype of non-Hodgkin's lymphoma.Morris SW et al
    110900482000CD30(+) anaplastic large cell lymphoma: a review of its histopathologic, genetic, and clinical features.Stein H et al
    113108342001Molecular characterization of a new ALK translocation involving moesin (MSN-ALK) in anaplastic large cell lymphoma.Tort F et al

    Summary

    Fusion gene

    MSN/ALK MSN (Xq12) ALK (2p23.2) COF 421 422 467|MSN/ALK MSN (Xq12) ALK (2p23.2) M|MSN/ALK MSN (Xq12) ALK (2p23.2) M t(X;2)(q11;p23)|MSN/ALK MSN (Xq12) ALK (2p23.2) TIC

    Citation

    Jean-Loup Huret

    t(X;2)(q11;p23) MSN/ALK

    Atlas Genet Cytogenet Oncol Haematol. 2001-08-01

    Online version: http://atlasgeneticsoncology.org/haematological/1216/t(x;2)(q11;p23)

    External Links