title: A BACH2-BCL2L1 fusion gene resulting from a t(6;20)(q15;q11.2) chromosomal translocation in the lymphoma cell line BLUE-1.
abstract: Abnormalities of the long arm of chromosome 6 are a common feature in various B-cell malignancies. In most cases, the genes involved have not yet been clearly identified. We have molecularly characterized the recently established Burkitt lymphoma cell line BLUE-1 that carries a t(6;20)(q15;q11.2) rearrangement in addition to the typical t(8;14) with MYC-IGH fusion. To identify the gene loci involved on both chromosomes we applied a sequential BAC clone mapping strategy. By using RT-PCR we were finally able to detect a chimeric mRNA transcript showing a fusion of the first (non-coding) exon of BACH2 (BTB and CNC homology 1, basic leucine zipper transcription factor 2) on 6q15 to the second exon of BCL2L1 (BCL-X) on 20q11. Various fusion transcripts were detected for different BCL2L1 (BCL-XL) isoforms. The fusion ultimately results in strong expression of the BCL2L1 (BCL-XL) anti-apoptosis protein, as demonstrated by immunoblotting. This is the first report that shows the involvement of both BCL2L1 and the transcription factor BACH2 in a chromosomal rearrangement. It points to BACH2 as a possibly important target in lymphomas with 6q aberrations, although other genes on 6q are probably also involved in these cases. Moreover, it suggests that members of the BCL2 anti-apoptosis gene family other than BCL2 itself might also be involved in lymphoma.
authors.affiliation: Institut für Medizinische Genetik, Charité CVK, Berlin, Germany.
authors.forename: Seval
authors.initials: S
authors.lastname: Türkmen
authors.forename: Mathias
authors.initials: M
authors.lastname: Riehn
authors.forename: Eva
authors.initials: E
authors.lastname: Klopocki
authors.forename: Mara
authors.initials: M
authors.lastname: Molkentin
authors.forename: Richard
authors.initials: R
authors.lastname: Reinhardt
authors.forename: Thomas
authors.initials: T
authors.lastname: Burmeister
mesh_terms: D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics*; D002051:Burkitt Lymphoma / Q000235:genetics*; D045744:Cell Line, Tumor; D002890:Chromosomes, Human, Pair 20 / Q000235:genetics*; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D006801:Humans; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics*; D051020:bcl-X Protein / Q000235:genetics*
chemical_list: C491123:BACH2 protein, human; D050976:Basic-Leucine Zipper Transcription Factors; D015514:Oncogene Proteins, Fusion; D051020:bcl-X Protein