Related Experiment Videos
Characterization of centromere alterations in liposarcomas
N Sirvent1, A Forus, W Lescaut
1UF Recherche Clinique 0952, CHU de Nice, Université de Nice-Sophia Antipolis, France.
Genes, Chromosomes & Cancer
|August 26, 2000
Summary
Atypical lipomas and well-differentiated liposarcomas (ALP-WDLPS) exhibit stable, abnormal chromosomes lacking typical centromeres. These analphoid chromosomes may form neocentromeres, aiding tumor cell stability and selective advantage.
Area of Science:
- Genetics
- Cancer Biology
- Molecular Cytogenetics
Background:
- Supernumerary ring and large marker chromosomes characterize atypical lipomas and well-differentiated liposarcomas (ALP-WDLPS).
- These abnormal chromosomes often contain amplified 12q14-15 sequences and segments from other chromosomes.
- Centromeric alterations, specifically a lack of alpha-satellite sequences, are noted in these stably transmitted chromosomes.
Observation:
- C-banding, FISH, and immunostaining were performed on 8 liposarcoma cases (5 ALP-WDLPS, 3 dedifferentiated/high-grade LPS).
- ALP-WDLPS supernumerary chromosomes lacked detectable alpha-satellite sequences but showed centromeric activity via kinetochore detection.
- High-grade and dedifferentiated liposarcomas displayed different patterns, with some having amplified chromosome 12 sequences on typical centromeres or markers with centromeres from other chromosomes.
Findings:
- ALP-WDLPS consistently shows stable analphoid chromosomes, a specific abnormality.
- Centromeric activity in ALP-WDLPS supernumerary chromosomes is present despite the absence of alpha-satellite DNA.
- Neocentromere formation is proposed as a mechanism for stability in ALP-WDLPS neoplastic cells.
Implications:
- The formation of neocentromeres may confer a selective advantage in neoplastic cells.
- Epigenetic mechanisms possibly activate non-centromeric sequences in these complex chromosomes.
- Understanding these chromosomal abnormalities provides insights into liposarcoma development and stability.