t(11;17)(q13;q21) NUMA1/RARA

1998-05-01   Franck Viguié 

Clinics and Pathology

Disease

atypical M3 AML (in most cases, M3 AML is characterized by a t(15;17)(q25;q21))

Epidemiology

exceptional (only 1 case fully described), a 6 mth old male patient

Clinics

multiple cutaneous localizations; blue-green macules on the scalp and the trunk; coagulation parameters and platelets count were normal

Prognosis

complet remission obtained with ATRA treatment and autologous bone marrow transplantation (38 mths disease-free follow up after BMT)

Cytogenetics

Additional anomalies

no

Variants

3 related translocations observed in M3 AML; the first is the common translocation (15;17) and the two others are extremelly rare; all these translocations involve a breakpoint at 17q21, in RARa, which fuses with different partners: 1- t(15;17)(q22;q21), fusion with PML in 15q22; 2- t(5;17)(q32;q12), fusion with NPM1 in 5q32, encoding for a RNA processing protein; 3- t(11;17)(q23;q21), fusion with PLZF in 11q23, a transcription factor.

Genes Involved and Proteins

Gene name
NUMA1 (nuclear mitotic apparatus protein 1)
Location
11q13.4
Protein description
NuMA protein is an essential component for the formation and maintenance of mitotic spindle poles during mitosis; dimerization domain and nuclear localisation signal.
Gene name
RARA (Retinoic acid receptor, alpha)
Location
17q21.2
Protein description
wide expression; nuclear receptor; binds specific DNA sequences: HRE (hormone response elements); ligand and dimerization domain; role in growth and differentiation.

Result of the Chromosomal Anomaly

Description

fusion gene on der(11) encompassed by a lamba phage clone B350g; breakpoint in RARa gene in the usual breakpoint cluster region within intron 2.

Transcript

5 NuMA - 3 RARa transcript; no reciprocal 5 RARa - 3 NuMA transcript can be detected

Description

2284 amino acids, 260 kDa; includes the NH2-terminal globular domain and the alpha helical dimerization domain of NuMA (amino acids 1 to 1883) linked to the ligand-binding, dimerization and DNA-binding domains of RARa (amino acids 61 to 462)

Expression localisation

nuclear localisation, under the form of sheet-like nuclear aggregates which partially co-localizes with normal NuMA protein

Oncogenesis

as for the three other translocations associated with APL, the main consequence of NuMA-RARa fusion seems to be an alteration in the retinoid signalling pathway; as for PML, PLZF or NPM, NuMA, the forth fusion partner of RARa would " share the capacity to participate in protein-protein interactions, which may result in the formation of abnormal heterodimers or aggregates in which co-activators of retinoid signalling are sequestered "

Bibliography

Pubmed IDLast YearTitleAuthors
92881091997Fusion of retinoic acid receptor alpha to NuMA, the nuclear mitotic apparatus protein, by a variant translocation in acute promyelocytic leukaemia.Wells RA et al
86184561996A new variant translocation in acute promyelocytic leukaemia: molecular characterization and clinical correlation.Wells RA et al

Summary

Fusion gene

NUMA1/RARA NUMA1 (11q13.4) RARA (17q21.2) M t(11;17)(q13;q21)|NUMA1/RARA NUMA1 (11q13.4) RARA (17q21.2) TIC

Citation

Franck Viguié

t(11;17)(q13;q21) NUMA1/RARA

Atlas Genet Cytogenet Oncol Haematol. 1998-05-01

Online version: http://atlasgeneticsoncology.org/haematological/1126/t(11;17)(q13;q21)-numa1-rara

External Links