scholarly journals Chromosome Instability Accounts for Reverse Metastatic Outcomes of Pediatric and Adult Synovial Sarcomas

2013 ◽  
Vol 31 (5) ◽  
pp. 608-615 ◽  
Author(s):  
Pauline Lagarde ◽  
Joanna Przybyl ◽  
Céline Brulard ◽  
Gaëlle Pérot ◽  
Gaelle Pierron ◽  
...  

Purpose Synovial sarcoma (SS) occurs in both children and adults, although metastatic events are much more common in adults. Whereas the importance of the t(X;18) translocation in SS oncogenesis is well established, the genetic basis of SS metastasis is still poorly understood. We recently reported expression (CINSARC; Complexity Index in Sarcoma) and Genomic Index prognostic signatures related to chromosome integrity in sarcomas and GI stromal tumors. Here we investigate whether these signatures can also predict outcomes in SS. Patients and Methods One hundred patients who had primary untreated SS tumors were selected for expression and genomic profiling in a training/validation approach. Results CINSARC and Genomic Index have strong independent and validated prognostic values (P < .001). By comparing expression profiles of tumors with or without metastasis, 14 genes that are common to the CINSARC signature were identified, and the two top-ranked genes, KIF14 and CDCA2, were validated as prognostic markers in an independent cohort. Comparing genomic profiles of adult versus pediatric SS, we show that metastasis is associated with genome complexity in both situations and that the adult genome is more frequently rearranged. Accordingly, pediatric patients with an even genomic profile do not develop metastasis. Conclusion Metastasis development in SS is strongly associated with chromosome complexity, and CINSARC and Genomic Index are validated independent prognostic factors. The differences in metastasis frequency between adults and children are associated with genome instability, which is much more frequent in adults. Genomic Index is potentially the best overall biomarker and clearly the most clinically relevant, considering that genome profiling from formalin-fixed samples is already used in pathology.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 9536-9536
Author(s):  
Fred Chibon ◽  
Pauline Lagarde ◽  
Joanna Przybyl ◽  
Celine Brulard ◽  
Antoine Italiano ◽  
...  

9536 Background: Synovial sarcoma (SS) is one of the rare sarcomas that occurs in adolescents as well as in adults. Nevertheless, metastasis occurs with a lowest frequency in the former, 10 vs 50% respectively. In almost all cases, a characteristic translocation t(X;18)(p11.2;q11.2) exists and the importance of this translocation in SS oncogenesis is well established, but the genetic basis of SS metastasis is still poorly understood. We recently published expression (CINSARC) and genomic (GI) signatures related to chromosome integrity control that predict outcome in undifferentiated sarcomas and GIST and ask whether these signatures could also predict outcome in SS. Methods: To asses this issue we selected in the European sarcoma database CONTICABASE 92 primary untreated SS for expression and genomic profiling. Results: As demonstrated by metastasis-free survival, CINSARC and GI have strong and independent prognostic values (p = 1.6 x 10-5 and p = 4 x 10-6, respectively). Comparing expression profiles of tumors with or without metastasis in a training series of 58 SS, a 52-genes signature was identified and validated in an independent series of 34 SS. Fourteen of these genes are common with CINSARC and these 52 genes are involved the same pathways than CINSARC, mitosis checkpoints and chromosome integrity. Comparing genomic profiles of adult versus pediatric SS we show that in both situations metastasis is associated to genome complexity and that the adult genome is highly more frequently rearranged. In line with this, the pediatric good-prognosis patients, according to GI, do not develop metastasis. Conclusions: Results clearly indicate that SS metastasis development is strongly associated with chromosome complexity and that CINSARC and GI are powerful prognostic factors. Data also mean that the metastasis frequency difference between adult and children likely is associated to the genome instability which is highly more frequent in adults. Finally, among these tree signatures, GI is potentially the best overall and clearly the most clinically relevant considering that CGH from FFPE samples is already used in the daily practice of pathology.


2021 ◽  
Author(s):  
Radhakrishnan Kanagaraj ◽  
Richard Mitter ◽  
Theodoros Kantidakis ◽  
Matthew Edwards ◽  
Anaid Benitez ◽  
...  

Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased transcription stress near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. In the absence of Senataxin, we found that Cockayne Syndrome protein CSB was required for the recruitment of the transcription-coupled repair endonucleases (XPG and XPF) and recombination protein RAD52 to target and resolve transcription bubbles containing R-loops, leading to error prone repair and genomic instability. These results show that transcription stress is an important contributor to SETX mutation-associated chromosome fragility and AOA2.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Katherine R. Dobbs ◽  
Paula Embury ◽  
Emmily Koech ◽  
Sidney Ogolla ◽  
Stephen Munga ◽  
...  

Abstract Background Age-related changes in adaptive and innate immune cells have been associated with a decline in effective immunity and chronic, low-grade inflammation. Epigenetic, transcriptional, and functional changes in monocytes occur with aging, though most studies to date have focused on differences between young adults and the elderly in populations with European ancestry; few data exist regarding changes that occur in circulating monocytes during the first few decades of life or in African populations. We analyzed DNA methylation profiles, cytokine production, and inflammatory gene expression profiles in monocytes from young adults and children from western Kenya. Results We identified several hypo- and hyper-methylated CpG sites in monocytes from Kenyan young adults vs. children that replicated findings in the current literature of differential DNA methylation in monocytes from elderly persons vs. young adults across diverse populations. Differentially methylated CpG sites were also noted in gene regions important to inflammation and innate immune responses. Monocytes from Kenyan young adults vs. children displayed increased production of IL-8, IL-10, and IL-12p70 in response to TLR4 and TLR2/1 stimulation as well as distinct inflammatory gene expression profiles. Conclusions These findings complement previous reports of age-related methylation changes in isolated monocytes and provide novel insights into the role of age-associated changes in innate immune functions.


2019 ◽  
Vol 21 (5) ◽  
pp. 1742-1755 ◽  
Author(s):  
Siqi Bao ◽  
Hengqiang Zhao ◽  
Jian Yuan ◽  
Dandan Fan ◽  
Zicheng Zhang ◽  
...  

Abstract Emerging evidence revealed the critical roles of long non-coding RNAs (lncRNAs) in maintaining genomic instability. However, identification of genome instability-associated lncRNAs and their clinical significance in cancers remain largely unexplored. Here, we developed a mutator hypothesis-derived computational frame combining lncRNA expression profiles and somatic mutation profiles in a tumor genome and identified 128 novel genomic instability-associated lncRNAs in breast cancer as a case study. We then identified a genome instability-derived two lncRNA-based gene signature (GILncSig) that stratified patients into high- and low-risk groups with significantly different outcome and was further validated in multiple independent patient cohorts. Furthermore, the GILncSig correlated with genomic mutation rate in both ovarian cancer and breast cancer, indicating its potential as a measurement of the degree of genome instability. The GILncSig was able to divide TP53 wide-type patients into two risk groups, with the low-risk group showing significantly improved outcome and the high-risk group showing no significant difference compared with those with TP53 mutation. In summary, this study provided a critical approach and resource for further studies examining the role of lncRNAs in genome instability and introduced a potential new avenue for identifying genomic instability-associated cancer biomarkers.


2017 ◽  
Vol 37 (22) ◽  
Author(s):  
Michael C. Reubens ◽  
Sophie Rozenzhak ◽  
Paul Russell

ABSTRACT DNA replication involves the inherent risk of genome instability, since replisomes invariably encounter DNA lesions or other structures that stall or collapse replication forks during the S phase. In the fission yeast Schizosaccharomyces pombe, the multi-BRCT domain protein Brc1, which is related to budding yeast Rtt107 and mammalian PTIP, plays an important role in maintaining genome integrity and cell viability when cells experience replication stress. The C-terminal pair of BRCT domains in Brc1 were previously shown to bind phosphohistone H2A (γH2A) formed by Rad3/ATR checkpoint kinase at DNA lesions; however, the putative scaffold interactions involving the N-terminal BRCT domains 1 to 4 of Brc1 have remained obscure. Here, we show that these domains bind Rhp18/Rad18, which is an E3 ubiquitin protein ligase that has crucial functions in postreplication repair. A missense allele in BRCT domain 4 of Brc1 disrupts binding to Rhp18 and causes sensitivity to replication stress. Brc1 binding to Rhp18 and γH2A are required for the Brc1 overexpression suppression of smc6-74, a mutation that impairs the Smc5/6 structural maintenance of chromosomes complex required for chromosome integrity and repair of collapsed replication forks. From these findings, we propose that Brc1 provides scaffolding functions linking γH2A, Rhp18, and Smc5/6 complex at damaged replication forks.


2004 ◽  
Vol 7 (6) ◽  
pp. 577-582 ◽  
Author(s):  
Lei Shao ◽  
D. Ashley Hill ◽  
Elizabeth J. Perlman

The confident diagnosis of renal spindle cell tumors in children is often difficult. An immunohistochemical study of WT-1, Bcl-2, and CD34 was performed to determine their expression profiles and to assess the potential utility of these immunohistochemical markers in the differential diagnosis of 36 cases of renal spindle cell tumors of childhood. The cases included 11 stromal predominant Wilms tumors, 12 cellular mesoblastic nephromas, 9 clear cell sarcomas of the kidney (CCSK), and 4 monophasic synovial sarcomas. WT-1 was uniformly positive in primitive undifferentiated stromal Wilms tumors (6 of 6) and negative in the differentiating and differentiated stromal elements of Wilms tumors (0 of 5). WT-1 was also negative in cellular mesoblastic nephromas (0 of 12), CCSKs (0 of 12), and synovial sarcomas (0 of 4). Bcl-2 was expressed in all stromal Wilms tumors (11 of 11), all synovial sarcomas (4 of 4), some CCSKs (4 of 9), and none of the cellular mesoblastic nephromas (0 of 12). Although CD34 was absent in the tumor cells of all the tumors studied (0 of 36), CD34 immunohistochemistry nicely demonstrated the evenly distributed septal capillaries characteristic of CCSK in all 9 cases of this tumor. We conclude that a combination of WT-1 and Bcl-2 immunohistochemistry may aid in the distinction of stromal Wilms tumor, monophasic synovial sarcoma, cellular mesoblastic nephroma, and CCSK.


eLife ◽  
2013 ◽  
Vol 2 ◽  
Author(s):  
Lamia Wahba ◽  
Steven K Gore ◽  
Douglas Koshland

Genome instability in yeast and mammals is caused by RNA–DNA hybrids that form as a result of defects in different aspects of RNA biogenesis. We report that in yeast mutants defective for transcription repression and RNA degradation, hybrid formation requires Rad51p and Rad52p. These proteins normally promote DNA–DNA strand exchange in homologous recombination. We suggest they also directly promote the DNA–RNA strand exchange necessary for hybrid formation since we observed accumulation of Rad51p at a model hybrid-forming locus. Furthermore, we provide evidence that Rad51p mediates hybridization of transcripts to homologous chromosomal loci distinct from their site of synthesis. This hybrid formation in trans amplifies the genome-destabilizing potential of RNA and broadens the exclusive co-transcriptional models that pervade the field. The deleterious hybrid-forming activity of Rad51p is counteracted by Srs2p, a known Rad51p antagonist. Thus Srs2p serves as a novel anti-hybrid mechanism in vivo.


2019 ◽  
Author(s):  
Rachel E Langston ◽  
Dominic Palazzola ◽  
Erin Bonnell ◽  
Raymund J. Wellinger ◽  
Ted Weinert

AbstractIn budding yeast, Cdc13, Stn1, and Ten1 form a telomere binding heterotrimer dubbed CST. Here we investigate the role of Cdc13/CST in maintaining genome stability, using a Chr VII disome system that can generate recombinants, loss, and enigmatic unstable chromosomes. In cells expressing a temperature sensitive CDC13 allele, cdc13F684S, unstable chromosomes frequently arise due to problems in or near a telomere. Hence, when Cdc13 is defective, passage through S phase causes Exo1-dependent ssDNA and unstable chromosomes, which then are the source for whole chromosome instability events (e.g. recombinants, chromosome truncations, dicentrics, and/or loss). Specifically, genome instability arises from a defect in Cdc13’s replication-dependent telomere capping function, not Cdc13s putative post-replication telomere capping function. Furthermore, the unstable chromosomes form without involvement of homologous recombination nor non-homologous end joining. Our data suggest that a Cdc13/CST defect in semi-conservative replication near the telomere leads to ssDNA and unstable chromosomes, which then are lost or subject to complex rearrangements. This system defines a links between replication-dependent chromosome capping and genome stability in the form of unstable chromosomes.


2019 ◽  
Author(s):  
Roshina Thapa ◽  
Swetha Vasudevan ◽  
Mimi Abo-Ayoub Ashqar ◽  
Eli Reich ◽  
Nataly Kravchenko-Balasha ◽  
...  

AbstractCancer cells have an altered transcriptome which contributes to their altered behaviors compared to normal cells. Indeed, many tumors express high levels of genes participating in meiosis or kinetochore biology, but the role of this high expression has not been fully elucidated. In this study we explore the relationship between this overexpression and genome instability and transformation capabilities of cancer cells. For this, we obtained expression data from 5 different cancer types which were analyzed using computational information-theoretic analysis. We were able to show that highly expressed meiotic/kinetochore genes were enriched in the altered gene expression subnetworks characterizing unstable cancer types with high chromosome instability (CIN). However, altered subnetworks found in the cancers with low CIN did not include meiotic and kinetochore genes. Representative gene candidates, found by the analysis to be correlated with a CIN phenotype, were further explored by transfecting genomically-stable (HCT116) and unstable (MCF7) cancer cell lines with vectors overexpressing those genes. This overexpression resulted in an increase in the numbers of abnormal cell divisions and defective spindle formations and in increased transformation properties in stable cancer HCT116 cells. Interestingly, the same properties were less affected by the overexpressed genes in the unstable MCF7 cancer cells. Our results indicate that overexpression of both meiosis and kinetochore genes is capable of driving genomic instability and cancer progression.


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