Expression of reciprocal fusion transcripts of the HMGIC and LPP genes in parosteal lipoma.
Parosteal lipomas are rare benign neoplasms of adipose tissue that exhibit a contiguous relationship with the periosteum. These lipomas of the bone share some histopathologic features with their commonly occurring soft tissue counterparts. The latter are well-characterized cytogenetically, primarily by rearrangements involving chromosome region 12q13-q15. In particular, translocations involving 12q13-q15 are prominent, with chromosomal region 3q27-q28 as the most frequent translocation partner. Recently, we established that the genes HMGIC at 12q15 and LPP at 3q27-28 are affected by the 3;12-translocation and demonstrated that, as a direct result, HMGIC/LPP and LPP/HMGIC fusion transcripts are expressed in soft tissue lipomas. In this study, cytogenetic and molecular analyses revealed similar findings in a parosteal lipoma. Specifically, a t(3;12)(q28;q14) was detected cytogenetically in a parosteal lipoma from a 51-year-old female and subsequently confirmed by FISH utilizing a chromosome 3 breakpoint spanning YAC probe and chromosome 12 breakpoint flanking cosmid probes. RT-PCR analysis showed expression of HMGIC/LPP and LPP/HMGIC fusion transcripts in this parosteal lipoma; nucleotide sequence analysis revealed that these transcripts are identical to those expressed in soft tissue lipomas characterized by a 3;12-translocation. These findings lend further support to a common histopathogenesis between lipomas of soft tissue and parosteal origin.
Petit
M M
MM
Laboratory for Molecular Oncology, University of Leuven, Belgium.
Swarts
S
S
Bridge
J A
JA
Van de Ven
W J
WJ
D001859:Bone Neoplasms / Q000235:genetics; D002881:Chromosomes, Human, Pair 12; D002893:Chromosomes, Human, Pair 3; D003598:Cytoskeletal Proteins; D005260:Female; D025743:HMGA2 Protein; D006609:High Mobility Group Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D060588:LIM Domain Proteins; D008067:Lipoma / Q000235:genetics*; D008875:Middle Aged; D010521:Periosteum; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012313:RNA / Q000032:analysis; D011993:Recombinant Fusion Proteins / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012983:Soft Tissue Neoplasms / Q000235:genetics; D014178:Translocation, Genetic; D014407:Tumor Cells, Cultured
D003598:Cytoskeletal Proteins; D025743:HMGA2 Protein; D006609:High Mobility Group Proteins; D060588:LIM Domain Proteins; C103594:LPP protein, human; D011506:Proteins; D011993:Recombinant Fusion Proteins; D012313:RNA