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Progress of polysaccharide-based tissue adhesives. Carbohydr Polym 2024; 327:121634. [PMID: 38171653 DOI: 10.1016/j.carbpol.2023.121634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 01/05/2024]
Abstract
Recently, polymer-based tissue adhesives (TAs) have gained the attention of scientists and industries as alternatives to sutures for sealing and closing wounds or incisions because of their ease of use, low cost, minimal tissue damage, and short application time. However, poor mechanical properties and weak adhesion strength limit the application of TAs, although numerous studies have attempted to develop new TAs with enhanced performance. Therefore, next-generation TAs with improved multifunctional properties are required. In this review, we address the requirements of polymeric TAs, adhesive characteristics, adhesion strength assessment methods, adhesion mechanisms, applications, advantages and disadvantages, and commercial products of polysaccharide (PS)-based TAs, including chitosan (CS), alginate (AL), dextran (DE), and hyaluronic acid (HA). Additionally, future perspectives are discussed.
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Deleterious and ethnic-related BRCA1/2 mutations in tissue and blood of Egyptian colorectal cancer patients and its correlation with human papillomavirus. Clin Exp Med 2023; 23:5063-5088. [PMID: 37804357 PMCID: PMC10725364 DOI: 10.1007/s10238-023-01207-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 09/22/2023] [Indexed: 10/09/2023]
Abstract
This study aimed to identify BRCA1/2 mutational patterns in the tissue and blood of Egyptian colorectal cancer (CRC) patients and to study the possible correlation of this mutational pattern with Human papillomavirus (HPV) infection. Eighty-two colonoscopic biopsies and forty-six blood samples were collected from Egyptian CRC patients, as well as blood samples of age and sex-matched healthy controls (n = 43) were enrolled. The libraries were performed using Qiaseq Human BRCA1 and BRCA2 targeted DNA panel and sequenced via Ion proton sequencer. Also, the CRC tissues were subjected to conventional PCR targeting the HPV Late 1 (L1) region. Our analysis revealed that the BRCA-DNA damage pathway had been altered in more than 65% of the CRC patients. Comparing tissue and blood samples from CRC patients, 25 somatic mutations were found exclusively in tissue, while 41 germline mutations were found exclusively in blood. Additionally, we identified 23 shared BRCA1/2 pathogenic (PVs) mutations in both blood and tissue samples, with a significantly higher frequency in blood samples compared to tissue samples. The most affected exon in BRCA1 was exon 10, while the most affected exons in BRCA2 were 11, 14, 18, 24, and 27 exons. Notably, we revealed an ethnic-related cluster of polymorphism variants in our population closely related to South Asian and African ethnicities. Novel PVs were identified and submitted to the ClinVar database. HPV was found in 23.8% of the CRC tissues, and 54% of HPV-positive cases had somatic BRCA1/2 PVs. The results of this research point to a possible connection between infection with HPV and BRCA1/2 mutations in the occurrence of colorectal cancer in the Egyptian population, which has a mixed ethnic background. Our data also indicate that liquid biopsy (blood samples) may be more representative than tissue samples for detecting BRCA1/2 mutations. These findings may have implications for cancer screening and the development of personalized, targeted therapies, such as PARP inhibitors, which can effectively target BRCA1/2 mutations.
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Progress of tissue adhesives based on proteins and synthetic polymers. Biomater Res 2023; 27:57. [PMID: 37287042 DOI: 10.1186/s40824-023-00397-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/17/2023] [Indexed: 06/09/2023] Open
Abstract
In recent years, polymer-based tissue adhesives (TAs) have been developed as an alternative to sutures to close and seal incisions or wounds owing to their ease of use, rapid application time, low cost, and minimal tissue damage. Although significant research is being conducted to develop new TAs with improved performances using different strategies, the applications of TAs are limited by several factors, such as weak adhesion strength and poor mechanical properties. Therefore, the next-generation advanced TAs with biomimetic and multifunctional properties should be developed. Herein, we review the requirements, adhesive performances, characteristics, adhesive mechanisms, applications, commercial products, and advantages and disadvantages of proteins- and synthetic polymer-based TAs. Furthermore, future perspectives in the field of TA-based research have been discussed.
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Analysis of the complete genome of HBV genotypes F and H found in Brazil and Mexico using the next generation sequencing method. Ann Hepatol 2022; 27 Suppl 1:100569. [PMID: 34757035 DOI: 10.1016/j.aohep.2021.100569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/09/2021] [Accepted: 09/21/2021] [Indexed: 02/04/2023]
Abstract
INTRODUCTION AND OBJECTIVES Hepatitis B Virus is classified into ten different genotypes (A- J). Genotypes F and H cluster apart from others in phylogenetic trees and is particularly frequent in the Americas. The aim of this study was to sequence complete genomes of samples of HBV genotypes F and H from Brazil and Mexico using next generation sequencing (NGS) and to study relevant characteristics for the disease associated with this virus. MATERIALS AND METHODS Ninety plasma samples with detectable HBV DNA belonging to the F (n=59) and H (n=31) genotypes were submitted to amplification of the complete HBV genome by three different methologies. Data analysis was developed using bioinformatics tools for quality assurance and comprehensive coverage of the genome. Sequences were aligned with reference sequences for subgenotyping and detecting variants in relevant positions. A phylogenetical tree was constructed using Bayesian methods. RESULTS HBV genome of 31 samples were amplified and 18 of them were sequenced (HBV/F=16 and HBV/H=2). One genotype F sample was co-infected with the F1b and F3 subgenotypes, while the other samples were all F2a subgenotype. Two genotype H samples clustered with other Mexican sequences. The main variants observed were found in preS and S genes (7/18) and mutations in the precore/core region (11/18). CONCLUSIONS A NGS methodology was applied to F and H genotypes samples from Mexico and Brazil to fully characterize their sequences. This methodology will be relevant for clinical and epidemiological studies of hepatitis B in Latin America.
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Surveillance in Next-Generation Personalized Healthcare: Science and Ethics of Data Analytics in Healthcare. New Bioeth 2021; 27:295-319. [PMID: 34720071 DOI: 10.1080/20502877.2021.1993055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Advances in science and technology have allowed for incredible improvements in healthcare. Additionally, the digital revolution in healthcare provides new ways of collecting and storing large volumes of patient data, referred to as big healthcare data. As a result, healthcare providers are now able to use data to gain a deeper understanding of how to treat an individual in what is referred to as personalized healthcare. Regardless, there are several ethical challenges associated with big healthcare data that affect how personalized healthcare is delivered. To highlight these issues, this article will review the role of big data in personalized healthcare while also discussing the ethical challenges associated with it. The article will also discuss public health surveillance, its implications, and the challenges associated with collecting participants' information. The article will proceed by highlighting next generation technologies, including robotics and 3D printing. The article will conclude by providing recommendations on how patient privacy can be protected in next-generation personalized healthcare.
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Transcriptome sequencing and microsatellite marker discovery in Ailanthus altissima (Mill.) Swingle (Simaroubaceae). Mol Biol Rep 2021; 48:2007-2023. [PMID: 33730287 DOI: 10.1007/s11033-020-05402-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/25/2020] [Indexed: 10/21/2022]
Abstract
Ailanthus altissima Swingle, is a tree species native to East Asia and has a great potential in decorative, bioenergy and industrial applications in many countries. To date, despite its commercial importance, the genomic and genetic resources available for this species are still insufficient. In this study, we characterized the transcriptome of A. altissima and developed thirteen EST-SSRs (expressed sequence tag-simple sequence repeats) based on Illumina paired-end RNA sequencing (RNA-seq). Besides, we developed ten polymorphic chloroplast microsatellite (cpSSR) markers using the available chloroplast genome of A. altissima. The transcriptome data produced 87,797 unigenes, of which 64,891 (73.91%) unigenes were successfully annotated in at least one protein database. For cpSSR markers the number of detected alleles (N) per marker varied from three at cpSSR12 to twelve at cpSSR8, the unbiased haploid diversity indices (uh) varied from 0.111 to 0.485, and haploid diversity indices (h) ranged from 0.101 to 0.444 with an average unbiased haploid diversity index (uh) of 0.274. Overall, a total of 65 different cpSSR alleles were identified at the ten loci among 165 individuals of A. altissima. The allele number per locus for EST-SSRs varied from 2.143 to 9.357, and the values of observed and expected heterozygosity ranged from 0.312 to 1.000 and 0.505 to 0.826, respectively. The molecular markers developed in this study will facilitate future genetic diversity, population structure, long distance-gene transfer and pollen-based gene flow analyses of A. altissima populations from its known distribution ranges in China focusing on planted and natural forest stands.
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Single-nucleotide variants, tumour mutational burden and microsatellite instability in patients with metastatic colorectal cancer: Next-generation sequencing results of the FIRE-3 trial. Eur J Cancer 2020; 137:250-259. [PMID: 32810748 DOI: 10.1016/j.ejca.2020.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/26/2020] [Accepted: 07/04/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND Molecular biomarkers and primary tumour sidedness guide treatment decisions in metastatic colorectal cancer. Comprehensive molecular profiling aims to identify targetable alterations and measure tumour mutational burden (TMB) to enable precision oncology. MATERIAL AND METHODS FoundationOne® next-generation sequencing identified single-nucleotide variants (SNVs), copy number alterations, high TMB (TMB-H) and high-grade microsatellite instability (MSI-H) in patients treated in the FIRE-3 trial. Data were correlated with objective response rate (ORR), progression-free survival (PFS) and overall survival (OS). RESULTS Three hundred seventy-three (49.6%) of 752 patients provided material for this analysis. Frequent SNVs included TP53, APC, KRAS, PIK3CA, BRAF, SMAD4 and FBXW7. KRAS, BRAF V600E and SMAD4 mutations were confirmed as prognostic biomarkers by logistic penalised regression for ORR. OS was significantly longer in patients with SMAD4 wild-type (WT) tumours than in those with SMAD4-mutated tumours (hazard ratio = 0.59 [95% confidence interval {CI} = 0.34-1.01], p = 0.05), with a higher probability of ORR [odds ratio, SMAD4 SNV versus WT = 0.32 [95% CI = 0.10-0.98], p = 0.05] when treated with cetuximab. MSI-H (30.0%, p = 0.03) and TMB-H (17.3%, p = 0.003) tumours were enriched by FBXW7 mutations. Numerically lower ORR, OS and PFS were observed in MSI-H tumours. CONCLUSIONS RAS, BRAF V600E and SMAD4 mutations were identified as poor prognostic biomarkers in patients of the FIRE-3 trial, whereas improved outcome was observed for BRAF non-V600E mutation. SMAD4 mutation might provide predictive relevance for cetuximab efficacy. MSI-H tumours showed numerically lower ORR, OS and PFS.
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Early KRAS oncogenic driver mutations in nonmucinous tissue of congenital pulmonary airway malformations as an indicator of potential malignant behavior. Hum Pathol 2020; 103:95-106. [PMID: 32681943 DOI: 10.1016/j.humpath.2020.07.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/07/2020] [Accepted: 07/10/2020] [Indexed: 11/30/2022]
Abstract
The potential for malignant degeneration is the most common reason for some practitioners to resect asymptomatic congenital pulmonary airway malformations (CPAMs). We aimed to investigate the potential of various immunohistochemical (IHC) and genomic biomarkers to predict the presence of mucinous proliferations (MPs) in CPAM. Archival CPAM tissue samples were re-assessed and underwent IHC analysis using a panel of differentiating markers (TTF1/CDX2/CC10/MUC2/MUC5AC/p16/p53/DICER1). In each sample, intensity of IHC staining was assessed separately in normal lung tissue, CPAM, and MP tissue, using a semiquantitative approach. Likewise, next-generation targeted sequencing of known adult lung driver mutations, including KRAS/BRAF/EGFR/ERBB2, was performed in all samples with MP and in control samples of CPAM tissue without MP. We analyzed samples of 25 CPAM type 1 and 25 CPAM type 2 and found MPs in 11 samples. They were all characterized by strong MUC5AC expression, and all carried a KRAS mutation in the MP and adjacent nonmucinous CPAM tissue, whereas the surrounding normal lung tissue was negative. By contrast, in less than half (5 out of 12) control samples lacking MP, the CPAM tissue also carried a KRAS mutation. KRAS mutations in nonmucinous CPAM tissue may identify lesions with a potential for malignant degeneration and may guide histopathological assessment and patient follow-up.
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Sequential blinded treatment decisions in ALK-positive non-small cell lung cancers in the era of precision medicine. Clin Transl Oncol 2020; 22:1425-1429. [PMID: 31955355 DOI: 10.1007/s12094-020-02290-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/03/2020] [Indexed: 11/25/2022]
Abstract
Next-generation ALK TKIs have become the new standard of care in first-line setting in advanced ALK-positive NSCLC patients. However, sequential strategies at progression are relevant, as may have an impact on patients' outcome. In this commentary we discuss whether genomic-tailored strategies at progression would be more suitable for improving outcome of ALK-positive NSCLC patients.
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Long walk to genomics: History and current approaches to genome sequencing and assembly. Comput Struct Biotechnol J 2019; 18:9-19. [PMID: 31890139 PMCID: PMC6926122 DOI: 10.1016/j.csbj.2019.11.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 11/03/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022] Open
Abstract
Genomes represent the starting point of genetic studies. Since the discovery of DNA structure, scientists have devoted great efforts to determine their sequence in an exact way. In this review we provide a comprehensive historical background of the improvements in DNA sequencing technologies that have accompanied the major milestones in genome sequencing and assembly, ranging from early sequencing methods to Next-Generation Sequencing platforms. We then focus on the advantages and challenges of the current technologies and approaches, collectively known as Third Generation Sequencing. As these technical advancements have been accompanied by progress in analytical methods, we also review the bioinformatic tools currently employed in de novo genome assembly, as well as some applications of Third Generation Sequencing technologies and high-quality reference genomes.
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Key Words
- BAC, Bacterial Artificial Chromosome
- Bioinformatics
- Genome assembly
- HGP, Human Genome Project
- HMW, high molecular weight
- HapMap, haplotype map
- NGS, Next Generation Sequencing
- Next-generation
- OLC, Overlap-Layout-Consensus
- QV, Quality Value (QV)
- Reference
- SBS, Sequencing by Synthesis
- SMRT, Single Molecule Real-Time
- SNPs, Single Nucleotide Polymorphisms
- SRA, Short Read Archive
- SV, Structural Variant
- Sequencing
- TGS, Third Generation Sequencing
- Third-generation
- WGS, Whole Genome Sequencing
- ZMW, Zero-Mode Waveguide
- bp, base pair
- dNTPs, deoxynucleoside triphosphates
- ddNTP, 2,3-dideoxynucleoside triphosphate
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Current trends and challenges in cancer management and therapy using designer nanomaterials. NANO CONVERGENCE 2019; 6:23. [PMID: 31304563 PMCID: PMC6626766 DOI: 10.1186/s40580-019-0193-2] [Citation(s) in RCA: 320] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 06/17/2019] [Indexed: 05/06/2023]
Abstract
Nanotechnology has the potential to circumvent several drawbacks of conventional therapeutic formulations. In fact, significant strides have been made towards the application of engineered nanomaterials for the treatment of cancer with high specificity, sensitivity and efficacy. Tailor-made nanomaterials functionalized with specific ligands can target cancer cells in a predictable manner and deliver encapsulated payloads effectively. Moreover, nanomaterials can also be designed for increased drug loading, improved half-life in the body, controlled release, and selective distribution by modifying their composition, size, morphology, and surface chemistry. To date, polymeric nanomaterials, metallic nanoparticles, carbon-based materials, liposomes, and dendrimers have been developed as smart drug delivery systems for cancer treatment, demonstrating enhanced pharmacokinetic and pharmacodynamic profiles over conventional formulations due to their nanoscale size and unique physicochemical characteristics. The data present in the literature suggest that nanotechnology will provide next-generation platforms for cancer management and anticancer therapy. Therefore, in this critical review, we summarize a range of nanomaterials which are currently being employed for anticancer therapies and discuss the fundamental role of their physicochemical properties in cancer management. We further elaborate on the topical progress made to date toward nanomaterial engineering for cancer therapy, including current strategies for drug targeting and release for efficient cancer administration. We also discuss issues of nanotoxicity, which is an often-neglected feature of nanotechnology. Finally, we attempt to summarize the current challenges in nanotherapeutics and provide an outlook on the future of this important field.
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Complementary and Alternative Medicine Strategies for Therapeutic Gut Microbiota Modulation in Inflammatory Bowel Disease and their Next-Generation Approaches. Gastroenterol Clin North Am 2017; 46:689-729. [PMID: 29173517 PMCID: PMC5909826 DOI: 10.1016/j.gtc.2017.08.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The human gut microbiome exerts a major impact on human health and disease, and therapeutic gut microbiota modulation is now a well-advocated strategy in the management of many diseases, including inflammatory bowel disease (IBD). Scientific and clinical evidence in support of complementary and alternative medicine, in targeting intestinal dysbiosis among patients with IBD, or other disorders, has increased dramatically over the past years. Delivery of "artificial" stool replacements for fecal microbiota transplantation (FMT) could provide an effective, safer alternative to that of human donor stool. Nevertheless, optimum timing of FMT administration in IBD remains unexplored, and future investigations are essential.
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Phylogenetic inference and SSR characterization of tropical woody bamboos tribe Bambuseae (Poaceae: Bambusoideae) based on complete plastid genome sequences. Curr Genet 2015; 62:443-53. [PMID: 26643654 DOI: 10.1007/s00294-015-0549-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 11/22/2015] [Accepted: 11/23/2015] [Indexed: 10/22/2022]
Abstract
The complete plastome sequencing is an efficient option for increasing phylogenetic resolution and evolutionary studies, as well as may greatly facilitate the use of plastid DNA markers in plant population genetic studies. Merostachys and Guadua stand out as the most common and the highest potential utilization bamboos indigenous of Brazil. Here, we sequenced the complete plastome sequences of the Brazilian Guadua chacoensis and Merostachys sp. to perform full plastome phylogeny and characterize the occurrence, type, and distribution of SRRs using 20 Bambuseae species. The determined plastome sequence of Merostachys sp. and G. chacoensis is 136,334 and 135,403 bp in size, respectively, with an identical gene content and typical quadripartite structure consisting of a pair of IRs separated by the LSC and SSC regions. The Maximum Likelihood and Bayesian Inference analyses produced phylogenomic trees identical in topology. These trees supported monophyly of Paleotropical and Neotropical Bamboos clades. The Neotropical bamboos segregated into three well-supported lineages, Chusqueinae, Guaduinae, and Arthrostylidiinae, with the last two forming a well-supported sister relationship. Paleotropical bamboos segregated into two well-supported lineages, Hickeliinae and Bambusinae + Melocanninae. We identified 141.8 cpSSR in Bambuseae plastomes and an inferior value (38.15) for plastome coding sequences. Among them, we identified 16 polymorphic SSR loci, with number of alleles varying from 3 to 10. These 16 polymorphic cpSSR loci in Bambuseae plastome can be assessed for the intraspecific level of polymorphism, leading to innovative highly sensitive phylogeographic and population genetics studies for this tribe.
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Mutational analysis by next generation sequencing of gastric type dysplasia occurring in hyperplastic polyps of the stomach: Mutations in gastric hyperplastic polyps. Exp Mol Pathol 2015; 99:468-73. [PMID: 26325218 DOI: 10.1016/j.yexmp.2015.08.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 08/24/2015] [Indexed: 11/21/2022]
Abstract
UNLABELLED Gastric hyperplastic polyps (GHP) are the most common type of polyps occurring in the stomach. Although GHP are broadly interpreted as benign lesions, they may progress to dysplasia and adenocarcinoma. OBJECTIVE In this study, we aimed to identify genomic mutations that characterize and may drive malignant transformation in GHP by using next-generation sequencing. Eight GHP (2 with dysplasia, 1 indefinite for dysplasia and 5 without dysplasia) were studied. Only large polyps (>1cm) with gastric differentiation were included in this study, while adenomatous polyps (intestinal-type) were excluded. Immunohistochemistry for MUC2, MUC5A, MUC6, CDX2, p53, and Ki67 was performed. DNA was extracted from formalin-fixed paraffin-embedded sections and sequenced for the detection of somatic mutations. Multiplex sequencing was done with the TrueSeq Amplicon Cancer Panel in the MiSeq platform. Variant annotation and visualization were performed using NextGENe (SoftGenetics) software. No pathogenic mutations were detected in GHP without dysplasia. TP53 gene mutations were the most common alteration in dysplastic GHP (2 of 2 dysplastic cases). PIK3CA mutation was identified in a GHP with pyloric-type dysplasia, whereas foveolar-type dysplasia carried TP53 mutations. In conclusion, TP53 gene mutations are a common alteration in the early dysplastic stage during malignant transformation of GHP. GHP with dysplasia may show dual differentiation. In our study, pyloric-type dysplasia was associated with a PIK3CA alteration whereas foveolar dysplasia carried TP53 mutations. The identification of carcinoma-associated mutations in large GHP provides additional evidence of their neoplastic potential and emphasizes the need for their complete resection and follow-up.
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tRNA gene copy number variation in humans. Gene 2013; 536:376-84. [PMID: 24342656 DOI: 10.1016/j.gene.2013.11.049] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 11/12/2013] [Accepted: 11/20/2013] [Indexed: 11/29/2022]
Abstract
The human tRNAome consists of more than 500 interspersed tRNA genes comprising 51 anticodon families of largely unequal copy number. We examined tRNA gene copy number variation (tgCNV) in six individuals; two kindreds of two parents and a child, using high coverage whole genome sequence data. Such differences may be important because translation of some mRNAs is sensitive to the relative amounts of tRNAs and because tRNA competition determines translational efficiency vs. fidelity and production of native vs. misfolded proteins. We identified several tRNA gene clusters with CNV, which in some cases were part of larger iterations. In addition there was an isolated tRNALysCUU gene that was absent as a homozygous deletion in one of the parents. When assessed by semiquantitative PCR in 98 DNA samples representing a wide variety of ethnicities, this allele was found deleted in hetero- or homozygosity in all groups at ~50% frequency. This is the first report of copy number variation of human tRNA genes. We conclude that tgCNV exists at significant levels among individual humans and discuss the results in terms of genetic diversity and prior genome wide association studies (GWAS) that suggest the importance of the ratio of tRNALys isoacceptors in Type-2 diabetes.
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