Intratumor heterogeneity of stage IA lung adenocarcinoma by multiregion whole exome sequencing and association with survival.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. 8545-8545 ◽  
Author(s):  
Kelly Quek ◽  
Jun Li ◽  
Junya Fujimoto ◽  
Jianhua Zhang ◽  
Jinliang Wang ◽  
...  
Keyword(s):  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Gene Mutations ◽  
Normal Lung ◽  
Intratumor Heterogeneity ◽  
Cancer Gene ◽  
Whole Exome ◽  
Potential Biomarker ◽  
Stage Ia ◽  
Early Carcinogenesis

8545 Background: Our previous study has suggested that complex genomic intratumor heterogeneity (gITH) was associated with an increased risk of relapse in patients with localized lung adenocarcinomas (LUAD). We have launched a study to investigate molecular and immune profile ITH of Stage IA NSCLC (a patient population with no optimal biomarker to guide postsurgical therapy) to understand the molecular evolution during early carcinogenesis and to identify biomarkers for early detection and intervention. Here, we report the preliminary analysis on gITH. Methods: We performed multiregion whole exome sequencing on 30 Stage IA LUAD and matched normal lung tissue to a median sequencing depth of 494x. 15 patients have relapsed within 3 years post-surgery (cases) and 15 patients have not relapsed with a minimum of 5-year postsurgical follow up (controls). Cases and controls are 1:1 matched for the key prognostic factors including tumor size, smoking status, age, gender, ethnicity and lobectomy or wedge resection. Shannon diversity index (SDI) was used to quantify ITH in each individual tumor. Kaplan-Meier method was used to evaluate the relationship between ITH and disease-free survival (DFS) as well as overall survival (OS). Results: Consistent with our previous study, 108 of 110 (98.2%) canonical cancer gene mutations were shared events by all regions of individual tumor. Compared to non-relapsed controls, tumors from relapsed cases demonstrated significantly higher degree of ITH (SDI of 1.78 in cases vs 1.58 for controls, p = 0.016). Higher degree of gITH was associated with shorter DFS (p = 0.008) and shorter OS (p = 0.0153). Significantly higher mutation burden was observed in tumors from relapsed patients (median of 10.86 mutations per MB in cases vs 7.45 mutations per MB in controls, p = 0.03). Analysis of gITH on a larger cohort and on predicted neoantigen, methylation, gene expression and immune profiles are in progress. Conclusions: Majority of cancer gene mutations are clonal events during early carcinogenesis of LUAD. Complex gITH may be associated with more aggressive biology and inferior clinical outcome in patients with Stage IA LUAD, therefore, may be evaluated as a potential biomarker.

scholarly journals Whole-exome sequencing identifies somatic mutations and intratumor heterogeneity in inflammatory breast cancer

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Rui Luo ◽  
Weelic Chong ◽  
Qiang Wei ◽  
Zhenchao Zhang ◽  
Chun Wang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Inflammatory Breast Cancer ◽  
Somatic Mutations ◽  
Gene Mutations ◽  
Intratumor Heterogeneity ◽  
Driver Gene ◽  
Tissue Samples ◽  
Whole Exome

AbstractInflammatory breast cancer (IBC) is the most aggressive form of breast cancer. Although it is a rare subtype, IBC is responsible for roughly 10% of breast cancer deaths. In order to obtain a better understanding of the genomic landscape and intratumor heterogeneity (ITH) in IBC, we conducted whole-exome sequencing of 16 tissue samples (12 tumor and four normal samples) from six hormone-receptor-positive IBC patients, analyzed somatic mutations and copy number aberrations, and inferred subclonal structures to demonstrate ITH. Our results showed that KMT2C was the most frequently mutated gene (42%, 5/12 samples), followed by HECTD1, LAMA3, FLG2, UGT2B4, STK33, BRCA2, ACP4, PIK3CA, and DNAH8 (all nine genes tied at 33% frequency, 4/12 samples). Our data indicated that PTEN and FBXW7 mutations may be considered driver gene mutations for IBC. We identified various subclonal structures and different levels of ITH between IBC patients, and mutations in the genes EIF4G3, IL12RB2, and PDE4B may potentially generate ITH in IBC.

scholarly journals The identification of novel gene mutations for degenerative lumbar spinal stenosis using whole-exome sequencing in a Chinese cohort

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Xin Jiang ◽  
Dong Chen
Keyword(s):  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Spinal Stenosis ◽  
Lumbar Spinal Stenosis ◽  
Gene Mutations ◽  
Specific Gene ◽  
Single Nucleotide ◽  
Degenerative Lumbar Spinal Stenosis ◽  
Whole Exome ◽  
Lumbar Spinal

Abstract Background Degenerative lumbar spinal stenosis (DLSS) is a common lumbar disease that requires surgery. Previous studies have indicated that genetic mutations are implicated in DLSS. However, studies on specific gene mutations are scarce. Whole-exome sequencing (WES) is a valuable research tool that identifies disease-causing genes and could become an effective strategy to investigate DLSS pathogenesis. Methods From January 2016 to December 2017, we recruited 50 unrelated patients with symptoms consistent with DLSS and 25 unrelated healthy controls. We conducted WES and exome data analysis to identify susceptible genes. Allele mutations firstly identified potential DLSS variants in controls to the patients’ group. We conducted a site-based association analysis to identify pathogenic variants using PolyPhen2, SIFT, Mutation Taster, Combined Annotation Dependent Depletion, and Phenolyzer algorithms. Potential variants were further confirmed using manual curation and validated using Sanger sequencing. Results In this cohort, the major classification variant was missense_mutation, the major variant type was single nucleotide polymorphism (SNP), and the major single nucleotide variation was C > T. Multiple SNPs in 34 genes were identified when filtered allele mutations in controls to retain only patient mutations. Pathway enrichment analyses revealed that mutated genes were mainly enriched for immune response-related signaling pathways. Using the Novegene database, site-based associations revealed several novel variants, including HLA-DRB1, PARK2, ACTR8, AOAH, BCORL1, MKRN2, NRG4, NUP205 genes, etc., were DLSS related. Conclusions Our study revealed that deleterious mutations in several genes might contribute to DLSS etiology. By screening and confirming susceptibility genes using WES, we provided more information on disease pathogenesis. Further WES studies incorporating larger DLSS patient cohorts are required to comprehend the genetic landscape of DLSS pathophysiology fully.

scholarly journals Whole-exome sequencing associates novel CSMD1 gene mutations with familial Parkinson disease

2017 ◽  
Vol 3 (5) ◽  
pp. e177 ◽  
Author(s):  
Javier Ruiz-Martínez ◽  
Luis J. Azcona ◽  
Alberto Bergareche ◽  
Jose F. Martí-Massó ◽  
Coro Paisán-Ruiz
Keyword(s):  
Parkinson Disease ◽  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Genome Wide Association Study ◽  
Single Gene ◽  
Gene Mutations ◽  
Complement Control Protein ◽  
Genome Wide ◽  
Whole Exome ◽  
A Genome

Objective:Despite the enormous advancements made in deciphering the genetic architecture of Parkinson disease (PD), the majority of PD is idiopathic, with single gene mutations explaining only a small proportion of the cases.Methods:In this study, we clinically evaluated 2 unrelated Spanish families diagnosed with PD, in which known PD genes were previously excluded, and performed whole-exome sequencing analyses in affected individuals for disease gene identification.Results:Patients were diagnosed with typical PD without relevant distinctive symptoms. Two different novel mutations were identified in the CSMD1 gene. The CSMD1 gene, which encodes a complement control protein that is known to participate in the complement activation and inflammation in the developing CNS, was previously shown to be associated with the risk of PD in a genome-wide association study.Conclusions:We conclude that the CSMD1 mutations identified in this study might be responsible for the PD phenotype observed in our examined patients. This, along with previous reported studies, may suggest the complement pathway as an important therapeutic target for PD and other neurodegenerative diseases.

Whole Exome Sequencing Reveals Spectrum of Gene Mutations in Pediatric AML

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 124-124
Author(s):  
Norio Shiba ◽  
Kenichi Yoshida ◽  
Yusuke Okuno ◽  
Yuichi Shiraishi ◽  
Yasunobu Nagata ◽  
...  
Keyword(s):  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Conflicts Of Interest ◽  
Massively Parallel Sequencing ◽  
Gene Mutations ◽  
Pediatric Leukemia ◽  
Protein Coding ◽  
Whole Exome ◽  
Recurrent Mutations ◽  
Pediatric Aml

Abstract Abstract 124 Background Pediatric acute myeloid leukemia (AML) comprises ∼20% of pediatric leukemia, representing one of the major therapeutic challenges in pediatric oncology with the current overall survival remains to be ∼60%. As for the molecular pathogenesis of pediatric AML, it has been well established that gene fusions generated by recurrent chromosomal translocations, including t(15;17), t(8;21), inv(16) and t(9;11), play critical roles in leukemogenesis. However, they are not sufficient for leukemogenesis, indicating apparent need of additional genetic hits, and approximately 20% of pediatric AML cases lack any detectable chromosomal abnormalities (normal karyotype AML). Currently, a number of gene mutations have been implicated in the pathogenesis of both adult and pediatric AML, including mutations of RAS, KIT and FLT3, and more recently, a new class of mutational targets have been reported in adult AML, including CEBPA, NPM1, DNMT3A, IDH1/2, TET2 and EZH2. However, mutations of the latter class of gene targets seem to be rare in pediatric AML cases, whereas other abnormalities such as a NUP98-NSD1 fusion are barely found in adult cases, indicating the discrete pathogenesis between both AML at least in their subsets. Meanwhile, the recent development of massively parallel sequencing technologies has provided a new opportunity to discover genetic changes across the entire genomes or protein-coding sequences in human cancers at a single-nucleotide level, which could be successfully applied to the genetic analysis of pediatric AML to obtain a better understanding of its pathogenesis. Methods In order to reveal a complete registry of gene mutations and other genetic lesions, we performed whole exome sequencing of paired tumor-normal specimens from 23 pediatric AML cases using Illumina HiSeq 2000. Although incapable of detecting non-coding mutations and gene rearrangements, the whole-exome approach is a well-established strategy for obtaining comprehensive spectrum of protein-coding mutations. Recurrently mutated genes were further examined for mutations in an extended cohort of 200 pediatric AML samples, using deep sequencing, in which the prevalence and relative allele frequencies of mutations were investigated. Results Whole-exome sequencing of paired tumor-normal DNA from 23 patients were analyzed with a mean coverage of more than x120, and 90 % of the target sequences were analyzed at more than x20 depth on average. A total of 237 somatic mutations or 10.3 mutations per sample were identified. Many of the recurrent mutations identified in this study involved previously reported targets in adult AML, such as FLT3, CEBPA, KIT, CBL, NRAS, WT1, MLL3, BCOR, BCORL1, EZH2, and major cohesin components including XXX and ZZZ. On the other hand, several genes were newly identified in the current study, including BRAF, CUL2 and COL4A5, which were validated for the clinical significance in an extended cohort of 200 pediatric cases. Discussion Whole exome sequencing unmasked a complexity of gene mutations in pediatric AML genomes. Our results indicated that a subset of pediatric AML represents a discrete entity that could be discriminated from the adult counterpart, in terms of the spectrum of gene mutations. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Diagnostic utility of exome sequencing for inherited peripheral neuropathies

2020 ◽  
Vol 10 (4) ◽  
pp. 12-26
Author(s):  
O. A. Shchagina ◽  
O. P. Ryzhkova ◽  
A. L. Chukhrova ◽  
T. V. Milovidova ◽  
P. Gundorova ◽  
...  
Keyword(s):  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Neuromuscular Disorders ◽  
Congenital Muscular Dystrophy ◽  
Gene Mutations ◽  
Research Centre ◽  
Congenital Myasthenic Syndrome ◽  
Hereditary Motor ◽  
Pathogenic Variants ◽  
Whole Exome

Introduction. Hereditary motor and sensory neuropathies, a highly genetic heterogeneous group of disorders, have a phenotype caused by peripheral nerve damage.Purpose of the study – to assess the extent of genetic heterogeneity of hereditary motor and sensory neuropathies in Russian patients and to evaluate the diagnostic effectiveness of using full-exome research methods to find the genetic cause of hereditary motor and sensory neuropathies.Materials and methods. The material for the study was DNA samples from 51 patients and their family members referred for whole exome sequencing to the DNA-diagnostics laboratory of Research Centre for Medical Genetics in 2017–2019. Methods: whole exome sequencing, Sanger sequencing, restriction fragment length polymorphism.Results. Whole exome sequencing in combination with segregation analysis of the pathogenic variants in families allowed to determine the cause of the disease in 41 % of cases. In another 16 % of cases, candidate genetic variants as a possible cause of the disease were revealed, but additional studies are needed to confirm it. The most frequently mutated gene was MFN2 caused neuropathy in 6 unrelated families. MPZ gene mutations were detected in two families, AARS gene mutations were revealed in another two families, and mutations in GJB1, HINT1, INF2, LRSAM1, LITAF, MME, NEFL, WWOX were detected once. Among the causal variants, mutations in B4GALNT1 caused spastic paraplegia, in COL6A1 led to Bethlem’s congenital muscular dystrophy, and in SYT2 caused congenital myasthenic syndrome indicating difficulties in differential diagnosis of inherited neuromuscular disorders. A PMP22 duplication was detected in 2 families prior to whole exome sequencing.Conclusion. Whole exome sequencing is very important for finding the molecular cause of hereditary motor and sensory neuropathies. In most cases, additional methods should be used to clarify the pathogenicity of variants detected by whole exome sequencing. However, it is necessary to remember that the most common cause of the disease is a large duplication of the region 17p11.2.

Genomic and immune intratumor heterogeneity in gastric linitis plastica.

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e16518-e16518
Author(s):  
Jin Huang ◽  
Guofeng Zhao ◽  
Qiu Peng ◽  
Jian Ma ◽  
Pansong Li ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
T Cells ◽  
Cell Carcinoma ◽  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Phylogenetic Trees ◽  
Linitis Plastica ◽  
Intratumor Heterogeneity ◽  
Small Indels ◽  
Whole Exome

e16518 Background: Gastric linitis plastica (LP) is a rare and aggressive type of gastric cancer (GC) for which the genomic landscape and architecture have gone largely undescribed. Methods: 4 LP patients were enrolled. 10 region tumor samples of each LP patient and matched peripheral blood were collected. Matched blood cells of each patient were also collected for removing germline background Whole-exome sequencing(WES), TCR sequencing, TCGA gastric cancer and several WES articles data were used to investigate intra and inter patient genomic and immune heterogeneity. Results: All 4 LP patients were female and were in stage III. LP biopsies were sequenced with median 290.6x effective depth. A total of 11,504 somatic mutations including 6,339 non-silent mutations were identified. The median non-silent tumor mutation burden (TMB) of biopsy samples was 3.23 mutations/Mb (range from 1.36 to 4.88), which was comparable to gastric adenocarcinoma(p = 0.3). Phylogenetic trees of 4 LP patients demonstrated clear evidence of branched evolution, and the phylogenetic trees varied extensively across the four cases. The percentages of trunk mutations of 4 LP were 12.8%, 5.4%, 5.4% and 30.7%, respectively, while the proportions of trunk neoantigens were 6.2%, 2.2%, 12% and 12.4, respectivelyWhen comparing LP to other multiregion WES studies, e.g., lung adenocarcinoma, renal cell carcinoma, and esophageal squamous cell carcinoma, LP was one of the most heterogeneous tumor types. The top mutational signatures in this cohort associated with spontaneous deamination, DNA mismatch repair (MMR), and small indels at repeats etc. Furthermore, profound TCR ITH was observed in all 4 LP patients. None of the T cell clones were shared among all tumor regions and 94.23-94.41% T cells were restricted to individual tumor regions. To quantify the TCR ITH, we utilized the Morisita overlap index (MOI), which ranged from 0.34 to 0.56 across different regions within the same tumors suggesting marked inter-individual TCR repertoire heterogeneity and profound intratumor TCR heterogeneity. Conclusions: Based on whole-exome sequencing and TCR sequencing, we demonstrate that LP is highly heterogeneous for mutations, neoantigens and T cells, which contributes to its poor prognosis.

Whole Exome Sequencing Shows a Paucity Of Somatic Gene Mutations In Pediatric Idiopathic Bone Marrow Failure Syndrome

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3708-3708
Author(s):  
Atsushi Narita ◽  
Hideki Muramatsu ◽  
Kenichi Yoshida ◽  
Yusuke Okuno ◽  
Asahito Hama ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Exome Sequencing ◽  
Whole Exome Sequencing ◽  
Somatic Mutations ◽  
Bone Marrow Failure ◽  
Gene Mutations ◽  
Bone Marrow Failure Syndrome ◽  
Cell Lineages ◽  
Bone Marrow Failure Syndromes ◽  
Whole Exome

Abstract Introduction Pancytopenia accompanied by a severe decrease in bone marrow (BM) cellularity in children can be due to a broad variety of underlying disorders. Appropriate classification of bone marrow failure syndrome in children is challenging, particularly in relation to the morphological distinction between aplastic anemia (AA), refractory cytopenia of childhood (RCC), and refractory cytopenia with multilineage dysplasia (RCMD). The goal of this study was to characterize the molecular pathogenesis of these conditions by identifying the full spectrum of gene mutations in 29 patients with these disorders through the use of exome sequencing. Patient and Methods Diagnosis of AA, RCC, or RCMD was made on basis of the 2008 World Health Organization (WHO) classification criteria. AA patients exhibited no morphologically dysplastic changes in any of their hematopoietic cell lineages, while RCC patients had<10% dysplastic changes in two or more cell lineages or >10% in one cell lineage. Patients classified as RCMD exhibited >10% of the dysplastic changes in two or more cell lineages. Blood and BM samples were obtained from 29 children (16 boys and 13 girls) with AA (n = 8), RCC (n = 11), or RCMD (n = 10). The median age at diagnosis was 11 years (range, 2–15 years). Exome capture from paired DNA (non-T cells/CD3+ lymphocyte) was performed using SureSelect® Human All Exon V3 (Agilent Technologies, Santa Clara, CA) covering 50 Mb of the coding exons, followed by massive parallel sequencing using HiSeq 2000 (Illumina, San Diego, CA) according to the manufacturer’s protocol. Candidate somatic mutations were detected through our pipeline for whole exome sequencing (genomon: http://genomon.hgc.jp/exome/index.html). All candidate somatic nucleotide changes were validated by Sanger sequencing. Results Exome sequencing pipeline identified a total of 193 non-synonymous somatic mutations or indels candidates among the 29 patients (range, 2–15 per patient). After validation by Sanger sequencing, one nonsense, 11 missense, and two frame-shift mutations were confirmed as non-silent somatic mutations. The average numbers of mutations per sample were not significantly different when comparing morphological diagnostic groups (0.50 in AA, 0.36 in RCC, 0.60 in RCMD). Of these validated genes, BCOR (n = 2) and CSK (n = 2) mutations were recurrent genetic events. BCOR is a frequent mutational target in myelodysplastic syndrome, whereas CSK somatic mutations were not reported in human cancers. BCOR mutations were found both in AA (c.472delA:p.S158fs; patient 13) and in RCMD (c.G3856T:p.E1286X; patient 39). Both patients with CSK mutations were classified as RCC (c.G994A:p.D332N; patient 23 and 27). When comparing the clinical outcomes of patients with somatic mutations (n = 7) versus those without somatic mutations (n = 22), response rate to immunosuppressive therapy at 6 months (50% vs. 50%), 5-year clonal evolution rate (95% confidential interval) [0% (0% - 0%) vs. 6% (0% - 26%)], and the 5-year overall survival rate (95% confidential interval) [100% (100% - 100%) vs. 95% (70% - 99%)] were not significantly different. Conclusion Whole exome sequencing analysis was used for gene mutational profiling of patients with idiopathic bone marrow failure syndromes; i.e., AA, RCC, and RCMD. Although BCOR and CSK somatic mutations were recurrently identified, idiopathic bone marrow failure syndromes in children are characterized by a paucity of gene mutations, irrespective of morphological diagnosis. These findings suggest that morphological diagnosis based on WHO classification system does not discriminate the mutational profile and pathogenesis of bone marrow failure in children. Disclosures: No relevant conflicts of interest to declare.

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