Copy capture
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Východiska: Přestože je bevacizumab prvním biologickým léčivem schváleným pro léčbu metastatického kolorektálního karcinomu (mCRC), neexistuje žádný zavedený DNA biomarker, který by zlepšil jeho účinnost a personalizoval léčbu. Materiál a metody: Sledováno bylo 30 pacientů s mCRC na terapii bevacizumabem (15 s dobrou odpovědí a 15 se špatnou odpovědí) z Fakultní nemocnice Olomouc. Pro analýzu variací v počtu kopií genů (copy number variation – CNV) byly použity vzorky FFPE a OncoScan FFPE Assay Kit, který zachycuje přibližně 900 nádorových genů. Výsledky: Ve skupině dobře reagujících pacientů bylo jako potenciálně významné pozitivní prediktivní nádorové biomarkery léčby bevacizumabem identifikováno 102 genů (klasifikovaných jako ATPázy, typ AAA, neuronální přenos signálu, regulace transkripce a domény typu PH superior). Ve špatně reagující skupině bylo identifikováno 74 potenciálně negativních prediktivních genů (klasifikovaných jako galektiny, signální dráha Jak-STAT, kaskáda MAPK, diferenciace a doména asociovaná s F-boxem). Závěr: V pilotní studii jsme našli slibné biomarkery variace počtu kopií odpovědi na bevacizumab v FFPE vzorcích nádorů pacientů s mCRC. Validační fáze by měla být zaměřena zejména na geny spojené s angiogenezí (AGRN, MAPK8, ARHGAP22, LGALS13, LGALS4, ZFP36 a MYC), tumorigenezí (DVL1) a proliferací tumoru (IFNL1, IFNL2, IFNL3, MAP3K10 a MAP4K1).
Background: Despite bevacizumab being the first biological agent approved for the treatment of metastatic colorectal cancer (mCRC), there is not any established DNA biomarker to improve its efficacy and personalize the treatment. Materials and methods: Thirty patients with mCRC on bevacizumab therapy (15 with a good response and 15 with a poor response) from the University Hospital Olomouc were followed. Formalin-fixed paraffin-embedded (FFPE) samples were used for copy number variation (CNV) analysis using the OncoScan FFPE Assay Kit in order to capture approx. 900 tumor genes. Results: In the group of good responding patients, 102 genes (classified as ATPases, type AAA, neuronal signal transmission, regulation of transcription, and superior domain PH type), potentially significant positive predictive tumor biomarkers of bevacizumab treatment, were found. In the poorly responding group, 74 potentially negative predictive genes (classified as galectines, Jak-STAT signalling pathway, MAPK cascade, differentiation, and F-box associated domain) were identified. Conclusion: In the pilot study, we found promising copy number variation biomarkers of bevacizumab response in FFPE samples of mCRC patients. The validation phase should be focused especially on the genes associated with angiogenesis (AGRN, MAPK8, ARHGAP22, LGALS13, LGALS4, ZFP36, and MYC), tumorigenesis (DVL1), and tumor proliferation (IFNL1, IFNL2, IFNL3, MAP3K10, and MAP4K1).
- MeSH
- bevacizumab aplikace a dávkování terapeutické užití MeSH
- kolorektální nádory * diagnóza farmakoterapie genetika patologie MeSH
- lidé MeSH
- metastázy nádorů farmakoterapie MeSH
- mutační analýza DNA metody MeSH
- nádorové biomarkery analýza genetika MeSH
- pilotní projekty MeSH
- protinádorové látky imunologicky aktivní aplikace a dávkování terapeutické užití MeSH
- variabilita počtu kopií segmentů DNA MeSH
- Check Tag
- lidé MeSH
BACKGROUND: Retroelements (REs) occupy a significant part of all eukaryotic genomes including humans. The majority of retroelements in the human genome are inactive and unable to retrotranspose. Dozens of active copies are repressed in most normal tissues by various cellular mechanisms. These copies can become active in normal germline and brain tissues or in cancer, leading to new retroposition events. The consequences of such events and their role in normal cell functioning and carcinogenesis are not yet fully understood. If new insertions occur in a small portion of cells they can be found only with the use of specific methods based on RE enrichment and high-throughput sequencing. The downside of the high sensitivity of such methods is the presence of various artifacts imitating real insertions, which in many cases cannot be validated due to lack of the initial template DNA. For this reason, adequate assessment of rare (< 1%) subclonal cancer specific RE insertions is complicated. RESULTS: Here we describe a new copy-capture technique which we implemented in a method called SeqURE for Sequencing Unknown of Retroposition Events that allows for efficient and reliable identification of new genomic RE insertions. The method is based on the capture of copies of target molecules (copy-capture), selective amplification and sequencing of genomic regions adjacent to active RE insertions from both sides. Importantly, the template genomic DNA remains intact and can be used for validation experiments. In addition, we applied a novel system for testing method sensitivity and precisely showed the ability of the developed method to reliably detect insertions present in 1 out of 100 cells and a substantial portion of insertions present in 1 out of 1000 cells. Using advantages of the method we showed the absence of somatic Alu insertions in colorectal cancer samples bearing tumor-specific L1HS insertions. CONCLUSIONS: This study presents the first description and implementation of the copy-capture technique and provides the first methodological basis for the quantitative assessment of RE insertions present in a small portion of cells.
- Publikační typ
- časopisecké články MeSH
Ciele: Analýza prenatálnych vzoriek za obdobie 2015–2020. Porovnanie miery detekcie klinicky relevantných variant cytogenetickou analýzou karyotypu a cytogenomickými metódami MLPA (Multiplex Ligation-Depent Probe Amplification) a mikročipmi (CMA – chromosomal microarray). Súbor a metodika: Analyzovaných bolo 1 029 prenatálnych vzoriek cytogenetickým hodnotením karyotypu (n = 1 029), cytogenomickými metódami MLPA (n = 144) a CMA (n = 111). Všetky nebalansované zmeny boli potvrdené metódou MLPA alebo CMA. Výsledky: Z analyzovaného súboru plodov, po odčítaní aneuploidií – 107 (10,40 %, n = 1 029), bolo analýzou karyotypu zachytených 22 štruktúrnych aberácií (2,39 %, n = 922) – deväť nebalansovaných zmien (0,98 %), 10 balansovaných zmien (1,08 %), jeden prípad nejasnej mozaiky (0,09 %), jeden prípad prítomnosti marker chromozómu (0,09 %) a jeden prípad diskordancie pohlavia (0,09 %). U 255 vzoriek s fyziologickým karyotypom indikovaných k cytogenomickému vyšetreniu bolo zachytených celkom osem (7,21 %, n = 111) patologických variant metódou CMA. Metódou MLPA bolo z týchto ôsmich patogénnych variant zachytených päť (3,47 %, n = 144). Celkový záchyt patogénnych variant metódami MLPA a CMA vrátane konfirmačných vyšetrení patologického karyotypu je 14 (5,14 %) a 17 (6,25 %) (n = 272). Záchyt patologických variant v skupine s izolovanými poruchami bol nižší než v skupine s mnohopočetnými poruchami (5,08 vs. 21,42 %). Záver: Potvrdila sa vyššia úspešnosť záchytu patologických variant so zmenou v počte kópií, metódou CMA než MLPA.
Objective: Analysis of prenatal samples from 2015 to 2020. Comparison detection rates of clinically relevant variants by cytogenetic karyotype analysis and cytogenomic MLPA (Multiplex Ligation-Depent Probe Amplification) and microarray methods (CMA – chromosomal microarray). Material and method: 1,029 prenatal samples were analyzed by cytogenetic karyotyping (N = 1,029), cytogenomic methods – MLPA (N = 144) and CMA (N = 111). All unbalanced changes were confirmed by MLPA or CMA. Results: From the analyzed set of fetuses, after subtraction of aneuploidies – 107 (10.40%, N = 1,029), 22 structural aberrations (2.39%, N = 922) – nine unbalanced changes (0.98%), 10 balanced changes (1.08%), one case of unclear mosaicism (0.09%), one case of presence of a marker chromosome (0.09%) and one case of sex discordance (0.09%) – were detected by karyotype analysis. A total of eight (7.21%, N = 111) pathological variants were detected by CMA in 255 samples with physiological karyotype indicated for cytogenomic examination. Five (3.47%, N = 144) of eight pathogenic variants were detected by MLPA method. The total capture of pathogenic variants by MLPA and CMA methods was 14 (5.14%) and 17 (6.25%) (N = 272), including confirmatory pathological karyotype testing. Detection of pathological variants in the isolated disorders group was lower than in the multiple disorders group (5.08 vs. 21.42%). Conclusion: A higher success rate for the detection of pathological copy number variation variants by the microarray method than by the MLPA method was confirmed.
- MeSH
- klinická studie jako téma MeSH
- lidé MeSH
- mikročipová analýza metody MeSH
- mozaicismus MeSH
- multiplexová polymerázová řetězová reakce metody MeSH
- plod MeSH
- prenatální diagnóza * MeSH
- těhotenství MeSH
- variabilita počtu kopií segmentů DNA MeSH
- vrozené vady * diagnóza genetika MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
B-cell neoplasms represent a clinically heterogeneous group of hematologic malignancies with considerably diverse genomic architecture recently endorsed by next-generation sequencing (NGS) studies. Because multiple genetic defects have a potential or confirmed clinical impact, a tendency toward more comprehensive testing of diagnostic, prognostic, and predictive markers is desired. This study introduces the design, validation, and implementation of an integrative, custom-designed, capture-based NGS panel titled LYmphoid NeXt-generation sequencing (LYNX) for the analysis of standard and novel molecular markers in the most common lymphoid neoplasms (chronic lymphocytic leukemia, acute lymphoblastic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and mantle cell lymphoma). A single LYNX test provides the following: i) accurate detection of mutations in all coding exons and splice sites of 70 lymphoma-related genes with a sensitivity of 5% variant allele frequency, ii) reliable identification of large genome-wide (≥6 Mb) and recurrent chromosomal aberrations (≥300 kb) in at least 20% of the clonal cell fraction, iii) the assessment of immunoglobulin and T-cell receptor gene rearrangements, and iv) lymphoma-specific translocation detection. Dedicated bioinformatic pipelines were designed to detect all markers mentioned above. The LYNX panel represents a comprehensive, up-to-date tool suitable for routine testing of lymphoid neoplasms with research and clinical applicability. It allows a wide adoption of capture-based targeted NGS in clinical practice and personalized management of patients with lymphoproliferative diseases.
- MeSH
- chromozomální aberace MeSH
- diagnostické techniky molekulární MeSH
- genetická predispozice k nemoci * MeSH
- genetická variace MeSH
- genomika metody MeSH
- lidé MeSH
- lymfoidní leukemie diagnóza genetika MeSH
- lymfom diagnóza genetika MeSH
- mutace INDEL MeSH
- nádorové biomarkery * MeSH
- prognóza MeSH
- translokace genetická MeSH
- variabilita počtu kopií segmentů DNA MeSH
- výpočetní biologie metody MeSH
- vysoce účinné nukleotidové sekvenování * metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Integration of multi-omics data can provide a more complex view of the biological system consisting of different interconnected molecular components, the crucial aspect for developing novel personalised therapeutic strategies for complex diseases. Various tools have been developed to integrate multi-omics data. However, an efficient multi-omics framework for regulatory network inference at the genome level that incorporates prior knowledge is still to emerge. RESULTS: We present IntOMICS, an efficient integrative framework based on Bayesian networks. IntOMICS systematically analyses gene expression, DNA methylation, copy number variation and biological prior knowledge to infer regulatory networks. IntOMICS complements the missing biological prior knowledge by so-called empirical biological knowledge, estimated from the available experimental data. Regulatory networks derived from IntOMICS provide deeper insights into the complex flow of genetic information on top of the increasing accuracy trend compared to a published algorithm designed exclusively for gene expression data. The ability to capture relevant crosstalks between multi-omics modalities is verified using known associations in microsatellite stable/instable colon cancer samples. Additionally, IntOMICS performance is compared with two algorithms for multi-omics regulatory network inference that can also incorporate prior knowledge in the inference framework. IntOMICS is also applied to detect potential predictive biomarkers in microsatellite stable stage III colon cancer samples. CONCLUSIONS: We provide IntOMICS, a framework for multi-omics data integration using a novel approach to biological knowledge discovery. IntOMICS is a powerful resource for exploratory systems biology and can provide valuable insights into the complex mechanisms of biological processes that have a vital role in personalised medicine.
- MeSH
- algoritmy MeSH
- Bayesova věta MeSH
- genové regulační sítě MeSH
- lidé MeSH
- nádory tračníku * MeSH
- systémová biologie metody MeSH
- variabilita počtu kopií segmentů DNA * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Cancer cells display complex genomic aberrations that include large-scale genetic rearrangements and epigenetic modulation that are not easily captured by short-read sequencing. This study presents a novel approach for simultaneous profiling of long-range genetic and epigenetic changes in matched cancer samples, focusing on clear cell renal cell carcinoma (ccRCC). ccRCC is a common kidney cancer subtype frequently characterized by a 3p deletion and the inactivation of the von Hippel-Lindau (VHL) gene. We performed integrated genetic, cytogenetic, and epigenetic analyses on paired tumor and adjacent nontumorous tissue samples. Optical genome mapping identified genomic aberrations as structural and copy number variations, complementing exome-sequencing findings. Single-molecule methylome and hydroxymethylome mapping revealed a significant global reduction in 5hmC level in both sample pairs, and a correlation between both epigenetic signals and gene expression was observed. The single-molecule epigenetic analysis identified numerous differentially modified regions, some implicated in ccRCC pathogenesis, including the genes VHL, PRCC, and PBRM1. Notably, pathways related to metabolism and cancer development were significantly enriched among these differential regions. This study demonstrates the feasibility of integrating optical genome and epigenome mapping for comprehensive characterization of matched tumor and adjacent tissue, uncovering both established and novel somatic aberrations.
- MeSH
- DNA vazebné proteiny MeSH
- epigeneze genetická * genetika MeSH
- epigenom * genetika MeSH
- karcinom z renálních buněk * genetika patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mapování chromozomů metody MeSH
- metylace DNA * genetika MeSH
- nádorový supresorový protein VHL genetika MeSH
- nádory ledvin * genetika patologie MeSH
- regulace genové exprese u nádorů MeSH
- transkripční faktory MeSH
- variabilita počtu kopií segmentů DNA * genetika MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Four accessions of hexaploid Elymus repens from its native Central European distribution area were analyzed using sequencing of multicopy (internal transcribed spacer, ITS) and single-copy (granule-bound starch synthase I, GBSSI) DNA in concert with genomic and fluorescent in situ hybridization (GISH and FISH) to disentangle its allopolyploid origin. Despite extensive ITS homogenization, nrDNA in E. repens allowed us to identify at least four distinct lineages. Apart from Pseudoroegneria and Hordeum, representing the major genome constituents, the presence of further unexpected alien genetic material, originating from species outside the Triticeae and close to Panicum (Paniceae) and Bromus (Bromeae), was revealed. GBSSI sequences provided information complementary to the ITS. Apart from Pseudoroegneria and Hordeum, two additional gene variants from within the Triticeae were discovered: One was Taeniatherum-like, but the other did not have a close relationship with any of the diploids sampled. GISH results were largely congruent with the sequence-based markers. GISH clearly confirmed Pseudoroegneria and Hordeum as major genome constituents and further showed the presence of a small chromosome segment corresponding to Panicum. It resided in the Hordeum subgenome and probably represents an old acquisition of a Hordeum progenitor. Spotty hybridization signals across all chromosomes after GISH with Taeniatherum and Bromus probes suggested that gene acquisition from these species is more likely due to common ancestry of the grasses or early introgression than to recent hybridization or allopolyploid origin of E. repens. Physical mapping of rDNA loci using FISH revealed that all rDNA loci except one minor were located on Pseudoroegneria-derived chromosomes, which suggests the loss of all Hordeum-derived loci but one. Because homogenization mechanisms seem to operate effectively among Pseudoroegneria-like copies in this species, incomplete ITS homogenization in our samples is probably due to an interstitial position of an individual minor rDNA locus located within the Hordeum-derived subgenome.
- MeSH
- Bayesova věta MeSH
- cytogenetické vyšetření metody MeSH
- fylogeneze MeSH
- genetická transkripce MeSH
- genetické databáze MeSH
- hybridizace in situ fluorescenční MeSH
- intergenová DNA MeSH
- lipnicovité genetika MeSH
- modely genetické MeSH
- přenos genů horizontální MeSH
- pseudogeny MeSH
- ribozomální DNA MeSH
- rostlinné geny MeSH
- synthasa škrobu genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVE: This study aimed to clarify the molecular epidemiology of hearing loss by identifying the responsible genes in patients without GJB2 mutations. STUDY DESIGN: Prospective genetic study. SETTING: Tertiary referral hospital. PATIENTS: Fifty one patients with bilateral sensorineural hearing loss, 20 men, and 31 women, mean age 24.9 years, range 3 to 64 years, from 49 families. GJB2 and deltaGJB6-D13S1830 mutations were excluded previously. INTERVENTION: Diagnostic. Sixty-nine genes reported to be causative of hearing loss were analyzed. Sequence capture technology, next-generation sequencing, and multiplex ligation-dependent probe amplification (MLPA) were used. Coverage of STRC was screened in Integrative Genomics Viewer software. MAIN OUTCOME MEASURE: Identification of causal pathogenic mutations in genes related to deafness. RESULTS: Five families (10%) had recessive STRC deletions or mutations. Five unrelated patients (10%) had recessive mutations in TMPRSS3, USH2A, PCDH15, LOXHD1, and MYO15A. Three families (6%) had autosomal dominant mutations in MYO6A, KCNQ4, and SIX1. One family (2%) had an X-linked POU3F4 mutation. Thus, we identified the cause of hearing loss in 28% of the families studied. CONCLUSIONS: Following GJB2, STRC was the second most frequently mutated gene in patients from the Czech Republic with hearing loss. To decrease the cost of testing, we recommend STRC deletion screening with MLPA before next-generation sequencing. The existence of a pseudogene and polymorphic STRC regions can lead to false-positive or false-negative results when copy number variation analysis is based on next-generation sequencing data.
- MeSH
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- membránové proteiny genetika MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mutace MeSH
- percepční nedoslýchavost vrozené genetika MeSH
- předškolní dítě MeSH
- prospektivní studie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
BACKGROUND: Alliinase is an important enzyme occurring in Allium species that converts precursors of sulfuric compounds, cysteine sulfoxides into a biologically active substance termed allicin. Allicin facilitates garlic defense against pests and produces health-promoting compounds. Alliinase is encoded by members of a multigene family that has not yet been sufficiently characterized, namely with regard to the copy numbers occurring within the genome and the polymorphisms among the family members. RESULTS: We cloned 45 full-length alliinase amplicons of cultivar (cv.) Jovan. Sequence analyses revealed nine different sequence variants (SVs), confirming the multilocus nature of this gene family. Several mutations in exons, mainly occurring in the first exon coding for vacuolar signal peptide, were found. These results enabled us to identify sequences with putatively modified vacuole-targeting abilities. We found additional sequence variants using partial amplicons. We estimated that the minimum number of gene copies in the diploid genome of the investigated cultivar was fourteen. We obtained similar results for another three cultivars, which differed in bolting type and place of origin. The further identification of high degree of polymorphisms in the intron regions allowed us to develop a specific polymerase chain reaction assay capable to capture intron length polymorphism (ILP). This assay was used to screen 131 additional accessions. Polymorphic data were used for cluster analysis, which separated the bolting and non-bolting garlic types and those with high cysteine-sulfoxide contents in a similar way as AFLP analysis in previous study. These newly developed markers can be further applied for the selection of desirable garlic genotypes. CONCLUSIONS: Detailed analysis of sequences confirmed multigenic nature of garlic alliinase. Intron and exon polymorphism analysis generated similar results as whole genome variability assessed previously by AFLP. Detected polymorphism is thus also associated with cysteine-sulphoxide content in individual genotypes. ILP markers capable to detect intron polymorphisms were newly developed. Developed markers could be applied in garlic breeding. Higher genetic variability found in bolting genotypes may indicates longer period of their sexual propagation in comparison with nonbolting genotypes.
Changes in expression of Klotho gene are associated with chronic kidney disease and its potential as early biomarker is being studied. We report, for the first time, the detection of Klotho gene by a biosensor platform. Self-assembled mixed monolayers (SAMs) as DNA immobilization method in screen-printed gold electrodes and a sandwich format detection were used in the development of an electrochemical genosensor for the detection of a 100-mer DNA fragment, copy of the partial region of the mRNA Klotho gene. The use of different binary and ternary SAMs based on aliphatic (mercaptohexanol, MCH, and hexanedithiol, HDT) and aromatic (mercaptophenylacetic acid, MPAA) thiol diluents and capture probe (CP) as sensing phases was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy. Multiple configurations were studied, changing the order of component addition and comparing co-immobilization and two-step immobilization processes. The procedure for binary SAM preparation consisting of sequential addition of a thiol diluent followed by CP was found to have the least detrimental impact on electrochemical performance. The signal-to-blank ratios increased considerably in the case of thioaromatic binary DNA monolayers, MPPA/CP, compared to the values obtained for aliphatic SAMs. Ternary monolayers formed by MCH and HDT rendered good fractional coverage levels and generated more reversible redox reactions at the surface, mostly when CP was firstly immobilized, CP/HDT/MCH. A significant reduction of the blank and non-specific (non-complementary sequence) signals was obtained with this ternary SAM, compared to binary SAMs and an increase of 2.42-fold of the S/B ratio (10 nM of target) compared with MPAA/CP SAMs. A linear response in the range of 5·10-10 to 5·10-8 M was obtained with CP/HDT/MCH monolayer, with a detection limit of 0.5 nM and RSD of 8.10%.
- MeSH
- alkalická fosfatasa chemie MeSH
- biosenzitivní techniky metody MeSH
- DNA sondy chemie genetika MeSH
- DNA analýza chemie genetika MeSH
- elektrochemické techniky metody MeSH
- fluoresceiny chemie MeSH
- fluorescenční barviva chemie MeSH
- glukuronidasa genetika MeSH
- hybridizace nukleových kyselin MeSH
- imobilizované nukleové kyseliny chemie genetika MeSH
- lidé MeSH
- limita detekce MeSH
- naftaleny chemie MeSH
- organofosforové sloučeniny chemie MeSH
- sulfhydrylové sloučeniny chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH