PARP1 Inhibitor and Trabectedin Combination Does Not Increase Tumor Mutational Burden in Advanced Sarcomas—A Preclinical and Translational Study

Drug-induced tumor mutational burden (TMB) may contribute to unleashing the immune response in relatively “immune-cold” tumors, such as sarcomas. We previously showed that PARP1 inhibition perpetuates the DNA damage induced by the chemotherapeutic agent trabectedin in both preclinical models and sarcoma patients. In the present work, we explored acquired genetic changes in DNA repair genes, mutational signatures, and TMB in a translational platform composed of cell lines, xenografts, and tumor samples from patients treated with trabectedin and olaparib combination, compared to cells treated with temozolomide, an alkylating agent that induces hypermutation. Whole-exome and targeted panel sequencing data analyses revealed that three cycles of trabectedin and olaparib combination neither affected the mutational profiles, DNA repair gene status, or copy number alterations, nor increased TMB both in homologous recombinant-defective and proficient cells or in xenografts. Moreover, TMB was not increased in tumor specimens derived from trabectedin- and olaparib-treated patients (5–6 cycles) when compared to pre-treatment biopsies. Conversely, repeated treatments with temozolomide induced a massive TMB increase in the SJSA-1 osteosarcoma model. In conclusion, a trabectedin and olaparib combination did not show mutagenic effects and is unlikely to prime subsequent immune-therapeutic interventions based on TMB increase. On the other hand, these findings are reassuring in the increasing warning of treatment-induced hematologic malignancies correlated to PARP1 inhibitor use.

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Genomic profiling reveals high frequency of DNA repair genetic aberrations in gallbladder cancer

Scientific Reports ◽

10.1038/s41598-020-77939-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Reham Abdel-Wahab ◽

Timothy A. Yap ◽

Russell Madison ◽

Shubham Pant ◽

Matthew Cooke ◽

...

Keyword(s):

Dna Repair ◽

Gallbladder Cancer ◽

Genomic Profiling ◽

Dna Repair Genes ◽

Repair Gene ◽

Dna Repair Gene ◽

Comprehensive Genomic Profiling ◽

Tumor Mutational Burden ◽

Repair Genes ◽

Cell Death Protein

AbstractDNA repair gene aberrations (GAs) occur in several cancers, may be prognostic and are actionable. We investigated the frequency of DNA repair GAs in gallbladder cancer (GBC), association with tumor mutational burden (TMB), microsatellite instability (MSI), programmed cell death protein 1 (PD-1), and its ligand (PD-L1) expression. Comprehensive genomic profiling (CGP) of 760 GBC was performed. We investigated GAs in 19 DNA repair genes including direct DNA repair genes (ATM, ATR, BRCA1, BRCA2, FANCA, FANCD2, MLH1, MSH2, MSH6, PALB2, POLD1, POLE, PRKDC, and RAD50) and caretaker genes (BAP1, CDK12, MLL3, TP53, and BLM) and classified patients into 3 groups based on TMB level: low (< 5.5 mutations/Mb), intermediate (5.5–19.5 mutations/Mb), and high (≥ 19.5 mutations/Mb). We assessed MSI status and PD-1 & PD-L1 expression. 658 (86.6%) had at least 1 actionable GA. Direct DNA repair gene GAs were identified in 109 patients (14.2%), while 476 (62.6%) had GAs in caretaker genes. Both direct and caretaker DNA repair GAs were significantly associated with high TMB (P = 0.0005 and 0.0001, respectively). Tumor PD-L1 expression was positive in 119 (15.6%), with 17 (2.2%) being moderate or high. DNA repair GAs are relatively frequent in GBC and associated with coexisting actionable mutations and a high TMB.

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BRCA Mutations, Homologous DNA Repair Deficiency, Tumor Mutational Burden, and Response to Immune Checkpoint Inhibition in Recurrent Ovarian Cancer

JCO Precision Oncology ◽

10.1200/po.20.00069 ◽

2020 ◽

pp. 665-679

Author(s):

Ying L. Liu ◽

Pier Selenica ◽

Qin Zhou ◽

Alexia Iasonos ◽

Margaret Callahan ◽

...

Keyword(s):

Dna Repair ◽

Immune Checkpoint ◽

Proportional Hazards ◽

Checkpoint Inhibitors ◽

Genetic Alterations ◽

Cox Proportional Hazards ◽

Sequencing Data ◽

Mutation Status ◽

Mutational Burden ◽

Tumor Mutational Burden

PURPOSE Homologous DNA repair–deficient (HRD) ovarian cancers (OCs), including those with BRCA1/2 mutations, have higher levels of genetic instability, potentially resulting in higher immunogenicity, and have been suggested to respond better to immune checkpoint inhibitors (ICIs) than homologous DNA repair–proficient OCs. However, clinical evidence is lacking. The study aimed to evaluate the associations between BRCA1/2 mutations, HRD, and other genomic parameters and response to ICIs and survival in OC. METHODS This is a single-institution retrospective analysis of women with recurrent OC treated with ICIs. BRCA1/2 mutation status and clinicopathologic variables were abstracted from the medical records. Targeted and whole-exome sequencing data available for a subset of patients were used to assess tumor mutational burden (TMB), HRD, and fraction of genome altered (FGA). ICI response was defined as lack of disease progression for ≥ 24 weeks. Associations of BRCA1/2 status and genomic alterations with progression-free survival (PFS) and overall survival (OS) were determined using Cox proportional hazards models. RESULTS Of the 143 women treated with ICIs, 134 had known BRCA1/2 mutation status. Deleterious germline or somatic BRCA1/2 mutations were present in 31 women (24%). There was no association between presence of BRCA1/2 mutations and response ( P = .796) or survival. Genomic analysis in 73 women found no association between TMB ( P = .344) or HRD ( P = .222) and response, PFS, or OS. There were also no significant differences in somatic genetic alterations between responders and nonresponders. High FGA was associated with an improvement in PFS ( P = .014) and OS ( P = .01). CONCLUSION TMB, BRCA1/2 mutations, and HRD are not associated with response or survival, cautioning against their use as selection criteria for ICI in recurrent OC. FGA should be investigated further as a biomarker of response to immunotherapy in OC.

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Enrichment of germline DNA-repair gene mutations in patients with colorectal cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.15_suppl.1500 ◽

2017 ◽

Vol 35 (15_suppl) ◽

pp. 1500-1500 ◽

Cited By ~ 1

Author(s):

Saud H Aldubayan ◽

Marios Giannakis ◽

Nathanael Moore ◽

Xinmeng Jasmine Mu ◽

G. Celine Han ◽

...

Keyword(s):

Colorectal Cancer ◽

Dna Repair ◽

Validation Cohort ◽

Germline Mutations ◽

Sequencing Data ◽

Discovery Cohort ◽

Repair Gene ◽

Germline Variants ◽

Risk Gene ◽

Dna Repair Gene

1500 Background: Twin studies showed that 30% of all colorectal cancer (CRC) patients have an inherited genetic susceptibility. Several CRC predisposition genes have been described to date. However, mutations in these genes explain the risk in only 5-10% of CRC cases. In this study, we hypothesized that some of the CRC heritability may be explained by excess disruptive germline mutations in DNA repair genes (DRGs). Methods: Exome sequencing data of 716 in the discovery cohort (CanSeq and NHS/HPFS studies) and 1609 CRC patients in the validation cohort (TCGA and NSCCG studies) were used to evaluate germline variants in a pre-selected group of 42 DRGs and 12 known CRC risk genes. Frequencies of disruptive mutations in our cohorts were examined relative to 27173 non-Finnish European cancer-free adults from the ExAC cohort to evaluate for enrichment. Results: Of 716 patients in the discovery cohort, 27 (3.8%) patients harbored germline mutations in APC (n = 11), MSH6 (n = 2), MUTYH (n = 11), CHEK2 (n = 1) and TP53 (n = 2). Interestingly, germline mutations in ATM and PALB2 were significantly enriched in our CRC discovery cohort (OR = 2.7; P = 0.044; and OR = 4.8; P = 0.026, respectively). Evaluation of germline data from another 1609 CRC patients (validation cohort) also showed significantly higher rates of ATM mutations (5; 0.7%; OR = 2.1; P = 0.044), and a trend for enrichment of PALB2 mutations (3; 0.4%; OR = 2.8; P = 0.056). Secondary analysis of actionable germline mutations in a highly penetrant cancer risk gene set ( ATM, BRCA1, BRCA2, BRIP1 and PALB2) suggest a broader enrichment trend in CRC patients for these genes (Discovery: OR = 1.7; P = 0.06; Validation: OR = 2; P = 1.96e-04). Conclusions: Our analysis of germline variants in 2325 CRC patients showed the first robust evidence for germline ATM mutations to confer a higher risk of developing CRC. We also presented evidence to support PALB2 as a potential novel CRC risk gene. Overall, our study shows that mutations in some DRGs may explain some of the missing CRC heritability. It also indicates that a significant percentage of CRC patients, who carry mutations in highly actionable genes where cancer screening recommendations for patients and families do exist, are not captured with current testing recommendations.

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Female age affects DNA repair gene expression in mouse GV oocytes from stimulated and unstimulated cycles and in MII oocytes matured in-vivo and in-vitro

10.26226/morressier.5af300ae738ab10027aa9430 ◽

2018 ◽

Author(s):

AR AR ◽

Sally Catt

Keyword(s):

Gene Expression ◽

Dna Repair ◽

Repair Gene ◽

Female Age ◽

Dna Repair Gene ◽

Mouse Gv Oocytes

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Faculty Opinions recommendation of Intraductal/ductal histology and lymphovascular invasion are associated with germline DNA-repair gene mutations in prostate cancer.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732569033.793548738 ◽

2018 ◽

Author(s):

Valeri Vasioukhin

Keyword(s):

Prostate Cancer ◽

Dna Repair ◽

Lymphovascular Invasion ◽

Gene Mutations ◽

Repair Gene ◽

Dna Repair Gene

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DNA Repair Gene Polymorphism and the Risk of Mitral Chordae Tendineae Rupture

Disease Markers ◽

10.1155/2015/825020 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6

Author(s):

Aysel Kalayci Yigin ◽

Mehmet Bulent Vatan ◽

Ramazan Akdemir ◽

Muhammed Necati Murat Aksoy ◽

Mehmet Akif Cakar ◽

...

Keyword(s):

Dna Repair ◽

Fragment Length Polymorphism ◽

Control Group ◽

Chordae Tendineae ◽

Repair Gene ◽

Repair Capacity ◽

Dna Repair Capacity ◽

Dna Repair Gene ◽

Increased Risk ◽

Polymerase Chain

Polymorphisms in Lys939Gln XPC gene may diminish DNA repair capacity, eventually increasing the risk of carcinogenesis. The aim of the present study was to evaluate the significance of polymorphism Lys939Gln in XPC gene in patients with mitral chordae tendinea rupture (MCTR). Twenty-one patients with MCTR and thirty-seven age and sex matched controls were enrolled in the study. Genotyping of XPC gene Lys939Gln polymorphism was carried out using polymerase chain reaction- (PCR-) restriction fragment length polymorphism (RFLP). The frequencies of the heterozygote genotype (Lys/Gln-AC) and homozygote genotype (Gln/Gln-CC) were significantly different in MCTR as compared to control group, respectively (52.4% versus 43.2%,p=0.049; 38.15% versus 16.2%,p=0.018). Homozygote variant (Gln/Gln) genotype was significantly associated with increased risk of MCTR (OR = 2.059; 95% CI: 1.097–3.863;p=0.018). Heterozygote variant (Lys/Gln) genotype was also highly significantly associated with increased risk of MCTR (OR = 1.489; 95% CI: 1.041–2.129;p=0.049). The variant allele C was found to be significantly associated with MCTR (OR = 1.481; 95% CI: 1.101–1.992;p=0.011). This study has demonstrated the association of XPC gene Lys939Gln polymorphism with MCTR, which is significantly associated with increased risk of MCTR.

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DNA Repair Gene Polymorphisms and Susceptibility to Urothelial Carcinoma in a Southeastern European Population

Current Oncology ◽

10.3390/curroncol28030174 ◽

2021 ◽

Vol 28 (3) ◽

pp. 1879-1885

Author(s):

Maria Samara ◽

Maria Papathanassiou ◽

Lampros Mitrakas ◽

George Koukoulis ◽

Panagiotis J. Vlachostergios ◽

...

Keyword(s):

Dna Repair ◽

Urothelial Carcinoma ◽

European Population ◽

Nucleotide Polymorphisms ◽

Environmental Carcinogens ◽

Repair Gene ◽

High Exposure ◽

Dna Repair Gene ◽

Increased Risk ◽

Xrcc3 Thr241met

Single nucleotide polymorphisms (SNPs) in DNA repair genes may predispose to urothelial carcinoma of the bladder (UCB). This study focused on three specific SNPs in a population with high exposure to environmental carcinogens including tobacco and alcohol. A case-control study design was used to assess for presence of XPC PAT +/−, XRCC3 Thr241Met, and ERCC2 Lys751Gln DNA repair gene SNPs in peripheral blood from patients with UCB and healthy individuals. One hundred patients and equal number of healthy subjects were enrolled. The XPC PAT +/+ genotype was associated with a 2-fold increased risk of UCB (OR = 2.16; 95%CI: 1.14–4; p = 0.01). The −/+ and +/+ XPC PAT genotypes were more frequently present in patients with multiple versus single tumors (p = 0.01). No association was detected between ERCC2 Lys751Gln genotypes/alleles, and risk for developing UCB. Presence of the XRCC3 TT genotype (OR = 0.14; 95%CI:0.07–0.25; p < 0.01) and of the T allele overall (OR = 0.26; 95%CI:0.16–0.41; p < 0.01) conferred a protective effect against developing UCB. The XPC PAT −/+ and XRCC3 Thr241Met SNPs are associated with predisposition to UCB. The XPC PAT −/+ SNP is also an indicator of bladder tumor multiplicity, which might require a more individualized surveillance and treatment.

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Patients with Systemic Sclerosis Present Increased DNA Damage Differentially Associated with DNA Repair Gene Polymorphisms

The Journal of Rheumatology ◽

10.3899/jrheum.130376 ◽

2014 ◽

Vol 41 (3) ◽

pp. 458-465 ◽

Cited By ~ 11

Author(s):

Gustavo Martelli Palomino ◽

Carmen L. Bassi ◽

Isabela J. Wastowski ◽

Danilo J. Xavier ◽

Yara M. Lucisano-Valim ◽

...

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Systemic Sclerosis ◽

Blood Cells ◽

Gene Polymorphisms ◽

Peripheral Blood Cells ◽

Dna Repair Genes ◽

Repair Gene ◽

Dna Repair Gene ◽

Repair Genes

Objective.Patients with systemic sclerosis (SSc) exhibit increased toxicity when exposed to genotoxic agents. In our study, we evaluated DNA damage and polymorphic sites in 2 DNA repair genes (XRCC1Arg399Gln andXRCC4Ile401Thr) in patients with SSc.Methods.A total of 177 patients were studied for DNA repair gene polymorphisms. Fifty-six of them were also evaluated for DNA damage in peripheral blood cells using the comet assay.Results.Compared to controls, the patients as a whole or stratified into major clinical variants (limited or diffuse skin involvement), irrespective of the underlying treatment schedule, exhibited increased DNA damage.XRCC1(rs: 25487) andXRCC4(rs: 28360135) allele and genotype frequencies observed in patients with SSc were not significantly different from those observed in controls; however, theXRCC1Arg399Gln allele was associated with increased DNA damage only in healthy controls and theXRCC4Ile401Thr allele was associated with increased DNA damage in both patients and controls. Further, theXRCC1Arg399Gln allele was associated with the presence of antinuclear antibody and anticentromere antibody. No association was observed between these DNA repair gene polymorphic sites and clinical features of patients with SSc.Conclusion.These results corroborate the presence of genomic instability in SSc peripheral blood cells, as evaluated by increased DNA damage, and show that polymorphic sites of theXRCC1andXRCC4DNA repair genes may differentially influence DNA damage and the development of autoantibodies.

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