Dataset Information

Recurrent 8q11-13 Aberrations Leading to PLAG1 Rearrangements, Including Novel Chimeras HNRNPA2B1::PLAG1 and SDCBP::PLAG1, in Lipomatous Tumors.

ABSTRACT:

Background/aim

Structural abnormalities of chromosome bands 8q11-13, resulting in rearrangement of the pleomorphic adenoma gene 1 (PLAG1), are known to characterize lipoblastoma, a benign fat cell tumor, found mainly in children. Here, we describe 8q11-13 rearrangements and their molecular consequences on PLAG1 in 7 lipomatous tumors in adults.

Materials and methods

The patients were 5 males and 2 females between 23 and 62 years old. The tumors, namely five lipomas, one fibrolipoma and one spindle cell lipoma, were examined using G-banding with karyotyping, fluorescence in situ hybridization (FISH; three tumors), RNA sequencing, reverse transcription (RT) PCR, and Sanger sequencing analyses (two tumors).

Results

All 7 tumors had karyotypic aberrations which included rearrangements of chromosome bands 8q11-13 (the criterion for selection into this study). FISH analyses with a PLAG1 break apart probe showed abnormal hybridization signals in both interphase nuclei and on metaphase spreads indicating PLAG1 rearrangement. RNA sequencing detected fusion between exon 1 of heterogeneous nuclear ribonucleoprotein A2/B1 (HNRNPA2B1) and exon 2 or 3 of PLAG1 in a lipoma and fusion between exon 2 of syndecan binding protein (SDCBP) and exon 2 or 3 of PLAG1 in a spindle cell lipoma. The HNRNPA2B1::PLAG1 and SDCBP::PLAG1 fusion transcripts were confirmed using RT-PCR/Sanger sequencing analyses.

Conclusion

As 8q11-13 aberrations/PLAG1-rearrangements/PLAG1-chimeras may evidently be a defining pathogenetic feature of lipogenic neoplasms of several histological types and not just lipoblastomas, we suggest that the term "8q11-13/PLAG1-rearranged lipomatous tumors" be generally adopted for this tumor subset.

SUBMITTER: Panagopoulos I

PROVIDER: S-EPMC9989671 | biostudies-literature | 2023 Mar-Apr

REPOSITORIES: biostudies-literature

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Publications

Recurrent 8q11-13 Aberrations Leading to <i>PLAG1</i> Rearrangements, Including Novel Chimeras <i>HNRNPA2B1::PLAG1</i> and <i>SDCBP::PLAG1</i>, in Lipomatous Tumors.

Panagopoulos Ioannis I Andersen Kristin K Gorunova Ludmila L Lund-Iversen Marius M Lobmaier Ingvild I Micci Francesca F Heim Sverre S

Cancer genomics & proteomics 20230301 2

<h4>Background/aim</h4>Structural abnormalities of chromosome bands 8q11-13, resulting in rearrangement of the pleomorphic adenoma gene 1 (PLAG1), are known to characterize lipoblastoma, a benign fat cell tumor, found mainly in children. Here, we describe 8q11-13 rearrangements and their molecular consequences on PLAG1 in 7 lipomatous tumors in adults.<h4>Materials and methods</h4>The patients were 5 males and 2 females between 23 and 62 years old. The tumors, namely five lipomas, one fibrolipom ...[more]

PMID: 36870688

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