NFIB rearrangement in superficial, retroperitoneal, and colonic lipomas with aberrations involving chromosome band 9p22.
Lipomas are frequently characterized by rearrangements resulting in the fusion of the HMGA2 gene (12q14.3) with a variety of partners. Chromosome band 9p22 rearrangements occur in about 1% of lipomas. We report here the molecular cytogenetic analysis of five cases of lipoma with a 9p22 aberration, including the first cytogenetic analysis of a colonic lipoma. Three out of the five cases showed a rearrangement of NFIB at 9p22.3. The NFIB rearrangement involved a fusion with HMGA2 in two cases. We have identified an in-frame fusion of the first three exons of HMGA2 with exon 6 of MSRB3 (12q14.3) and exons 8 and 9 of NFIB by using 3'RACE-PCR in a case of superficial lipoma. In a case of retroperitoneal lipoma we found a fusion of HMGA2 with NFIB by fluorescence in situ hybridization analysis. The colonic lipoma was characterized by a t(9;16;19)(p22;q21;q13) with a rearrangement of NFIB and no rearrangement of HMGA2. NFIB belongs to the nuclear factor I transcription family. It has been previously shown to be fused with HMGA2 in one case of lipoma and to be a recurrent partner of HMGA2 in pleormorphic adenoma of salivary glands. We here demonstrate that NFIB can also be rearranged independently from HMGA2, indicating a potentially important role in lipoma pathobiology. Our findings suggest that the rearrangement of NFIB might be associated with deep-seated lipomas, such as retroperitoneal or gastro-intestinal lipomas.
Italiano
Antoine
A
Laboratory of Solid Tumors Genetics, Nice University Hospital, Nice, France.
Ebran
Nathalie
N
Attias
Rita
R
Chevallier
Anne
A
Monticelli
Isabelle
I
Mainguené
Claire
C
Benchimol
Daniel
D
Pedeutour
Florence
F
D000328:Adult; D000368:Aged; D001483:Base Sequence; D002869:Chromosome Aberrations; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics*; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D007621:Karyotyping; D008067:Lipoma / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D051839:NFI Transcription Factors / Q000235:genetics* / Q000378:metabolism; D012186:Retroperitoneal Neoplasms / Q000235:genetics* / Q000473:pathology
D051839:NFI Transcription Factors; C110754:NFIB protein, human