Telomere and Centromere Staining Followed by M-FISH Improves Diagnosis of Chromosomal Instability and Its Clinical Utility

Abstract

Dicentric chromosomes are a relevant marker of chromosomal instability. Their appearance is associated with telomere dysfunction, leading to cancer progression and a poor clinical outcome. Here, we present Telomere and Centromere staining followed by M-FISH (TC+M-FISH) for improved detection of telomere dysfunction and the identification of dicentric chromosomes in cancer patients and various genetic syndromes. Significant telomere length shortening and significantly higher frequencies of telomere loss and deletion were found in the peripheral lymphocytes of patients with cancer and genetic syndromes relative to similar age-matched healthy donors. We assessed our technique against conventional cytogenetics for the detection of dicentric chromosomes by subjecting metaphase preparations to both approaches. We identified dicentric chromosomes in 28/50 cancer patients and 21/44 genetic syndrome patients using our approach, but only 7/50 and 12/44, respectively, using standard cytogenetics. We ascribe this discrepancy to the identification of the unique configuration of dicentric chromosomes. We observed significantly higher frequencies of telomere loss and deletion in patients with dicentric chromosomes (p < 10−4). TC+M-FISH analysis is superior to classical cytogenetics for the detection of chromosomal instability. Our approach is a relatively simple but useful tool for documenting telomere dysfunction and chromosomal instability with the potential to become a standard additional diagnostic tool in medical genetics and the clinic.

Telomere Length and Hematological Disorders: A Review

“…The risk for cancer development aggravates in relation to the decrease in telomere length (TL) and after the disease is consolidated the telomeres tend to elongate once again. This observation shows that critically shortened and dysfunctional telomeres contribute to genetic instability and oncogenesis (1,17,18).…”

“…Dysfunctions affecting the telomere complex might expose the DNA to enzymatic degradation leading to breaks, deletions, fusions and accumulation of DNA mutations. The consequence of this genomic instability is cancer progression and a worse prognosis for the afflicted patients (16,17).…”

Multi-omics comparison of malignant and normal uveal melanocytes reveals novel molecular features of uveal melanoma

“…For MP46, molecule N50 was 325.6kbp, label density was 16.9/100kbp and effective coverage of assembly was 84.5X. Telomere and centromere staining followed by M-FISH technique were applied on cytogenetics slides after colcemid (0.1µg/mL) treatment of MP41 and MP46 cells as described previously [41], [42] to identify numerical and structural chromosomal alterations as well as telomere instability. Briefly, UM cells were cultured in T75 in DMEM with 10-20% SVF depending on models (10% SVF: MP41, Mel202, OMM1, OMM2.3; 20%: MP46).…”

Lung Fibroblasts from Idiopathic Pulmonary Fibrosis Patients Harbor Short and Unstable Telomeres Leading to Chromosomal Instability

“…However, to the best of our knowledge, no data on chromosomal abnormalities have been reported in lung tissue of TRG mutation carriers. An automated approach based on cytogenetic preparations and fluorescence in situ hybridization (FISH) of telomeres and centromeres makes it possible to record telomere aberrations (i.e., telomere loss and terminal deletion) in vast numbers of cells and telomere length variation between samples [ 23 , 24 ].…”