Related Experiment Videos
Analysis of the INK4a/ARF locus in non-Hodgkin's lymphomas using two new internal microsatellite markers
Abstract:
Inactivation of the INK4a/ARF locus is a frequent event in non-Hodgkin's lymphomas (NHLs), which may be attributed to deletion, point mutation, and 5' CpG methylation at its promoter region. In the present study we evaluated the occurrence of deletions and genetic instability of INK4a/ARF locus in 30 paired normal and tumor samples of B cell NHLs by conducting an allelotypic analysis with two new polymorphic markers, one located at the intron 1 of p16INK4a gene and the other one placed downstream exon 1beta of p19ARF. Comparison of these results with those obtained in a previous paper using flanking markers (D9S171, D9S942, D9S958 and IFNA) allowed us to detect two new cases of microsatellite instability (L-446 and L-442), and to confirm the occurrence of LOH at the INK4a/ARF locus in one tumor (M-3770). On the contrary, this locus is not affected in three different tumors (L-421, L-272 and L-159) which exhibited LOH at some of the flanking markers.
Insights
Genetic instability and deletions at the INK4a/ARF locus are investigated in non-Hodgkin's lymphomas (NHLs). This study identifies new cases of microsatellite instability and confirms loss of heterozygosity in B cell NHLs.
Area of Science:
- Oncology
- Genetics
- Molecular Biology
Background:
- Inactivation of the INK4a/ARF locus is common in non-Hodgkin's lymphomas (NHLs).
- Mechanisms include deletion, mutation, and promoter methylation.
- The INK4a/ARF locus is a critical tumor suppressor.
Purpose of the Study:
- To evaluate deletions and genetic instability of the INK4a/ARF locus in B cell NHLs.
- To identify novel polymorphic markers for allelotypic analysis.
- To correlate locus alterations with flanking marker data.
Main Methods:
- Allelotypic analysis of 30 paired normal and tumor B cell NHL samples.
- Utilized two new polymorphic markers in p16INK4a and p19ARF genes.
- Compared results with flanking markers (D9S171, D9S942, D9S958, IFNA).
Main Results:
- Detected two new cases of microsatellite instability (L-446, L-442).
- Confirmed loss of heterozygosity (LOH) at the INK4a/ARF locus in one tumor (M-3770).
- Found the locus unaffected in three tumors with LOH at flanking markers.
Conclusions:
- The INK4a/ARF locus can be affected by genetic instability and deletions in B cell NHLs.
- Novel markers aid in detecting microsatellite instability.
- LOH at flanking markers does not always indicate INK4a/ARF locus involvement.