t(2;22)(p23;q11) CLTCL1/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.
  • The t(2;22)(p23;Q11.2) is very rare, and, like other 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(2;22) the localization is restricted to granules (vesicles) in the cytoplasm.

    • Phenotype stem cell origin

    CD30+; ALK+

    Clinics

    found in 1 case ( a 3 yr old girl in complete remission 1yr after end of treatment), perhaps 2 (a 52 yr old man).

    Genes Involved and Proteins

    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
    Gene name
    CLTCL1 (clathrin heavy polypeptide-like 1)
    Location
    22q11.21
    Protein description
    1640 amino acids, 187 kDa; component of the coat of vesicles originated from the plasma membrane or the golgi

    Result of the Chromosomal Anomaly

    Description

    5 CLTCL1 - 3 ALK2197 amino acids, 248-250 kDa; 1634 (nearly all the CLTCL1 protein) N-term amino acids from CLTCL1, fused to the 562 C-term amino acids from ALK (i.e. the entire cytoplasmic portion of ALK with the tyrosine kinase domain).

    Expression localisation

    cytoplasmic localization restricted to granules

    Oncogenesis

    constitutive autophosphorylation

    Bibliography

    Pubmed IDLast YearTitleAuthors

    Summary

    Fusion gene

    CLTCL1/ALK CLTCL1 (22q11.21) ALK (2p23.2) M t(2;22)(p23;q11)

    Citation

    Jean-Loup Huret

    t(2;22)(p23;q11) CLTCL1/ALK

    Atlas Genet Cytogenet Oncol Haematol. 2001-08-01

    Online version: http://atlasgeneticsoncology.org/haematological/1220/welcome