Atlas of Genetics and Cytogenetics in Oncology and Haematology


Home   Genes   Leukemias   Solid Tumors   Cancer-Prone   Deep Insight   Case Reports   Journals  Portal   Teaching   

X Y 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 NA

t(7;9)(q11;p13) PAX5/ELN

Written2007-04Marina Bousquet, Nicole Dastugue, Pierre Brousset
INSERM U563, Centre de Physiopathologie de Toulouse Purpan, Place Baylac, 31059 Toulouse Cedex, France.

(Note : for Links provided by Atlas : click)

Identity

ICD-Topo C420,C421,C424 BLOOD, BONE MARROW, & HEMATOPOIETIC SYS
ICD-Morpho 9811/3 B lymphoblastic leukaemia/lymphoma, NOS
Atlas_Id 1195
 
  t(7;9)(q11;p13) RHG-banding (Courtesy Nicole Dastugue).

Clinics and Pathology

Disease B-cell acute lymphoblastic leukemia (B-ALL)
Phenotype / cell stem origin Pre-B3 phenotype (CD10+ Cmu+) and pre-B2 phenotype (CD10+ Cmu-)
Embryonic origin Only two cases described: a 38-year-old male patient and a 16-year-old male patient.
Treatment GRAAL 2003 trial and LALA94 trial
Evolution Relapse post allograft for both patients
Prognosis Poor (16 months survival for both patients)

Cytogenetics

Additional anomalies del(9)(p11p13) in 1 of 2 cases but without PAX5 deletion

Genes involved and Proteins

Gene Name PAX5
Location 9p13
Dna / Rna The PAX5 locus spans approximately 200kb. PAX5 contains 10 exons and two distinct promoters resulting in two alternative 5' exons (1a and 1b). PAX5b is transcribed in the central nervous system and testis as well as in the B lymphoid lineage. PAX5a, also named B-cell specific activator protein (BSAP), is specifically transcribed in the B lymphoid lineage.
Protein PAX5 is a member of the highly conserved paired box (PAX)-domain family of transcription factors. The PAX5 plays an important role in cell differentiation and in embryonic development. PAX5 is expressed from early stages of B-cell development up to mature B-cells and is down-regulated during terminal differentiation into plasma cells. PAX5 contains a paired box domain (DNA binding domain), a conserved octapeptide motif and a partial homeodomain. Its C-terminal region contains a transcriptional activation domain and the extreme C-terminal region acts as a repression domain.
Gene Name ELN
Location 7q11
Dna / Rna ELN locus spans approximately 40kb and contains 33 exons.
Protein ELN is a 72-kDa insoluble extracellular matrix protein.

Result of the chromosomal anomaly

Hybrid gene
Description 5'PAX5-3'ELN, PAX5 exon 7 is fused in frame with ELN exon 2.
Transcript The same PAX5-ELN transcript was amplified for both patients. Of note, the two alternative transcripts PAX5a-ELN and PAX5b-ELN were presents. The reciprocal ELN-PAX5 fusion transcript could not be amplified.
Detection The fusion transcript can be detected by RT-PCR using the 5' PAX5 sense primer: 5'-CCCTGTCCATTCCATCAAGTCCTG-3'; the 3' ELN antisense primer 5'-ATGAGGTCGTGAGTCAGGGGTC-3'.
  
Fusion Protein
 
  Schematic representation of PAX5-ELN chimera. (A) Sequence of the in-frame fusion between exon 7 of PAX5 and exon 2 of ELN. (B) Structure of PAX5, PAX5-ELN and ELN proteins. PBD, Paired box domain; OCT, octapeptide; NLS, nuclear localization sequence; TD, transactivation domain; RD, repressor domain.
Description The PAX5-ELN fusion protein conserves the DNA binding domain of PAX5 and its NLS, but looses its transactivation and repression domain. The quasi entire sequence of ELN is preserved without its signal peptide.
Expression Localisation In HeLa cells transfected with the construction PAX5-ELN, the chimera is localized in the nucleus.
Oncogenesis PAX5-ELN acts as a dominant negative on wild-type PAX5 in in vitro experiments that could explain the blockade of differentiation in leukemic cells.
  

To be noted

Additional cases are needed to delineate the epidemiology of this rare entity:
you are welcome to submit a paper to our new Case Report section.

Bibliography

A novel PAX5-ELN fusion protein identified in B-cell acute lymphoblastic leukemia acts as a dominant negative on wild-type PAX5.
Bousquet M, Broccardo C, Quelen C, Meggetto F, Kuhlein E, Delsol G, Dastugue N, Brousset P
Blood. 2007 ; 109 (8) : 3417-3423.
PMID 17179230
 

Citation

This paper should be referenced as such :
Bousquet, Marina ; Dastugue, Nicole ; Brousset, Pierre
t(7;9)(q11;p13)
Atlas Genet Cytogenet Oncol Haematol. 2007;11(4):316-318.
Free journal version : [ pdf ]   [ DOI ]
On line version : http://AtlasGeneticsOncology.org/Anomalies/t0709q11p13ID1195.html


Other genes implicated (Data extracted from papers in the Atlas) [ 1 ]

Genes KMT2A

Translocations implicated (Data extracted from papers in the Atlas)

 t(7;9)(q11;p13) PAX5/ELN

External links

PAX5 (9p13.2) ELN (7q11.23)

PAX5 (9p13.2) ELN (7q11.23)

Mitelman databaset(7;9)(q11;p13) [Case List]    t(7;9)(q11;p13) [Association List] Mitelman database (CGAP - NCBI)
arrayMapTopo ( C42) Morph ( 9811/3) - arrayMap (UZH-SIB Zurich)  [auto + random 100 samples .. if exist ]   [tabulated segments]
 
Mitelman databasePAX5/ELN [MCList]  PAX5 (9p13.2) ELN (7q11.23)
TICdbPAX5/ELN  PAX5 (9p13.2) ELN (7q11.23)
 
Disease databaset(7;9)(q11;p13) PAX5/ELN
REVIEW articlesautomatic search in PubMed
Last year articlesautomatic search in PubMed
All articlesautomatic search in PubMed


© Atlas of Genetics and Cytogenetics in Oncology and Haematology
indexed on : Fri Jun 30 11:23:21 CEST 2017


Home   Genes   Leukemias   Solid Tumors   Cancer-Prone   Deep Insight   Case Reports   Journals  Portal   Teaching   

For comments and suggestions or contributions, please contact us

jlhuret@AtlasGeneticsOncology.org.