Heterogeneity of the API2-MALT1 gene rearrangement in MALT-type lymphoma

Leukemia. 2000 Nov;14(11):1967-74. doi: 10.1038/sj.leu.2401918.


The translocation t(11;18)(q21;q21), which is the most frequent chromosomal aberration in extranodal marginal zone B cell lymphomas of MALT-type, was characterised in a series of 34 biopsies, including 18 gastric non-Hodgkin's lymphomas (NHL) of MALT-type, six MALT-type NHL of extragastral origin and 10 extranodal large B cell lymphomas (LBL). Based on fluorescence in situ hybridisation, STS-PCR analysis and screening of genomic PAC libraries, a physical map of contiguous DNA probes on chromosome 11 was constructed containing the anti-apoptotic genes API2 and API1 adjacent to the translocation breakpoint. RACE-PCR experiments revealed MALT1 the chromosome 18-derived fusion partner of API2, which has also been reported recently by other groups. RT-PCR analysis and DNA sequencing demonstrated the expression of an API2-MALT1 fusion transcript in 18/24 gastral and extragastral MALT-type lymphomas. In none of 10 LBLs was a translocation specific RT-PCR product detected. Five variants of the fusion transcript were identified and in all instances the open reading frame of the fused portion of the MALT1 gene was maintained. The molecular analysis of these variants allowed the design of optimised assays for the diagnosis of the API2-MALT1 gene rearrangement.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caspases
  • Chromosome Mapping
  • Chromosomes, Human, Pair 11 / genetics*
  • Chromosomes, Human, Pair 11 / ultrastructure
  • Chromosomes, Human, Pair 18 / genetics*
  • Chromosomes, Human, Pair 18 / ultrastructure
  • Humans
  • In Situ Hybridization, Fluorescence
  • Inhibitor of Apoptosis Proteins
  • Lung Neoplasms / genetics
  • Lung Neoplasms / pathology
  • Lymphoma, B-Cell, Marginal Zone / genetics*
  • Lymphoma, B-Cell, Marginal Zone / pathology
  • Lymphoma, Large B-Cell, Diffuse / genetics
  • Lymphoma, Large B-Cell, Diffuse / pathology
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein
  • Neoplasm Proteins / genetics*
  • Oncogene Proteins, Fusion / genetics*
  • Polymerase Chain Reaction
  • Proteins / genetics*
  • Salivary Gland Neoplasms / genetics
  • Salivary Gland Neoplasms / pathology
  • Stomach Neoplasms / genetics
  • Stomach Neoplasms / pathology
  • Thyroid Neoplasms / genetics
  • Thyroid Neoplasms / pathology
  • Translocation, Genetic*
  • Ubiquitin-Protein Ligases


  • API2-MALT1 fusion protein, human
  • Inhibitor of Apoptosis Proteins
  • Neoplasm Proteins
  • Oncogene Proteins, Fusion
  • Proteins
  • BIRC2 protein, human
  • Ubiquitin-Protein Ligases
  • Caspases
  • MALT1 protein, human
  • Mucosa-Associated Lymphoid Tissue Lymphoma Translocation 1 Protein