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1.
PLoS One ; 19(4): e0299689, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38656936

RESUMO

The use of elephant ivory as a commodity is a factor in declining elephant populations. Despite recent worldwide elephant ivory trade bans, mammoth ivory trade remains unregulated. This complicates law enforcement efforts, as distinguishing between ivory from extant and extinct species requires costly, destructive and time consuming methods. Elephant and mammoth ivory mainly consists of dentine, a mineralized connective tissue that contains an organic collagenous component and an inorganic component of calcium phosphate minerals, similar in structure to hydroxyapatite crystals. Raman spectroscopy is a non-invasive laser-based technique that has previously been used for the study of bone and mineral chemistry. Ivory and bone have similar biochemical properties, making Raman spectroscopy a promising method for species identification based on ivory. This study aimed to test the hypothesis that it is possible to identify differences in the chemistry of mammoth and elephant ivory using Raman spectroscopy. Mammoth and elephant tusks were obtained from the Natural History Museum in London, UK. Included in this study were eight samples of ivory from Mammuthus primigenius, two samples of carved ivory bangles from Africa (Loxodonta species), and one cross section of a tusk from Elephas maximus. The ivory was scanned using an inVia Raman micro spectrometer equipped with a x50 objective lens and a 785nm laser. Spectra were acquired using line maps and individual spectral points were acquired randomly or at points of interest on all samples. The data was then analysed using principal component analysis (PCA) with use of an in-house MATLAB script. Univariate analysis of peak intensity ratios of phosphate to amide I and III peaks, and carbonate to phosphate peaks showed statistical differences (p<0.0001) in the average peak intensity ratios between Mammuthus primigenius, Loxodonta spp. and Elephas maximus. Full width at half maximum hight (FWHM)analysis of the phosphate peak demonstrated higher crystal maturity of Mammuthus primigenius compared to living elephant species. The results of the study have established that spectra acquired by Raman spectroscopy can be separated into distinct classes through PCA. In conclusion, this study has shown that well-preserved mammoth and elephant ivory has the potential to be characterized using Raman spectroscopy, providing a promising method for species identification. The results of this study will be valuable in developing quick and non-destructive methods for the identification of ivory, which will have direct applications in archaeology and the regulation of international trade.


Assuntos
Elefantes , Análise Espectral Raman , Animais , Análise Espectral Raman/métodos , Mamutes , Extinção Biológica , Análise de Componente Principal , Conservação dos Recursos Naturais/métodos , Animais Selvagens , Fósseis , Comércio de Vida Silvestre
2.
Artigo em Inglês | MEDLINE | ID: mdl-38609170

RESUMO

CONTEXT: The plasma metabolome is a functional readout of metabolic activity and is associated with phenotypes exhibiting sexual dimorphism, such as cardiovascular disease. Sex hormones are thought to play a key role in driving sexual dimorphism. OBJECTIVE: Gender-affirming hormone therapy (GAHT) is a cornerstone of transgender care, but longitudinal changes in the plasma metabolome with feminizing GAHT have not been described. METHODS: Blood samples were collected at baseline and after three and six months of GAHT from transgender women (n = 53). Participants were randomized to different anti-androgens, cyproterone acetate or spironolactone. NMR-based metabolomics was used to measure 249 metabolic biomarkers in plasma. Additionally, we used metabolic biomarker data from an unrelated cohort of children and their parents (n = 3,748) to identify sex- and age-related metabolite patterns. RESULTS: We identified 43 metabolic biomarkers altered after six months in both anti-androgen groups, most belonging to the very low- or low-density lipoprotein subclasses, with all but one showing a decrease. We observed a cyproterone acetate-specific decrease in glutamine, glycine, and alanine levels. Notably, of the metabolic biomarkers exhibiting the most abundant 'sex- and age-related' pattern (higher in assigned female children and lower in assigned female adults, relative to assigned males), 80% were significantly lowered after GAHT, reflecting a shift toward the adult female profile. CONCLUSION: Our results suggest an anti-atherogenic signature in the plasma metabolome after the first six months of feminizing GAHT, with cyproterone acetate also reducing specific plasma amino acids. This study provides novel insight into the metabolic changes occurring across feminizing GAHT.

3.
J Funct Biomater ; 15(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38535248

RESUMO

Bone tissue engineering using osteoconductive scaffolds holds promise for regeneration, with pearl powder gaining interest for its bioactive qualities. This study used freeze drying to create chitosan (CS) scaffolds with pearl/calcium phosphate (p/CaP) powders, mimicking bone tissue structurally and compositionally. Characterization included scanning electron microscopy (SEM) and mechanical testing. X-ray diffraction (XRD) Fourier-transform infrared-photoacoustic photo-acoustic sampling (FTIR-PAS), and FTIR- attenuated total reflectance (FTIR-ATR) were used to characterize p/CaP. In vitro tests covered degradation, cell activity, and SEM analysis. The scaffolds showed notable compressive strength and modulus enhancements with increasing p/CaP content. Porosity, ranging from 60% to 90%, decreased significantly at higher pearl/CaP ratios. Optimal cell proliferation and differentiation were observed with scaffolds containing up to 30 wt.% p/CaP, with 30 wt.% pearl powder and 30 wt.% p/CaP yielding the best results. In conclusion, pearl/calcium phosphate chitosan (p/CaP_CS) composite scaffolds emerged as promising biomaterials for bone tissue engineering, combining structural mimicry and favourable biological responses.

4.
Sci Adv ; 8(31): eabn4002, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35930640

RESUMO

Trained immunity describes the capacity of innate immune cells to develop heterologous memory in response to certain exogenous exposures. This phenomenon mediates, at least in part, the beneficial off-target effects of the BCG vaccine. Using an in vitro model of trained immunity, we show that BCG exposure induces a persistent change in active histone modifications, DNA methylation, transcription, and adenosine-to-inosine RNA modification in human monocytes. By profiling DNA methylation of circulating monocytes from infants in the MIS BAIR clinical trial, we identify a BCG-associated DNA methylation signature that persisted more than 12 months after neonatal BCG vaccination. Genes associated with this epigenetic signature are involved in viral response pathways, consistent with the reported off-target protection against viral infections in neonates, adults, and the elderly. Our findings indicate that the off-target effects of BCG in infants are accompanied by epigenetic remodeling of circulating monocytes that lasts more than 1 year.


Assuntos
Vacina BCG , Viroses , Adulto , Idoso , Metilação de DNA , Humanos , Recém-Nascido , Monócitos , Vacinação , Viroses/metabolismo
5.
Cancer Cell ; 40(8): 835-849.e8, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35839778

RESUMO

The proteome provides unique insights into disease biology beyond the genome and transcriptome. A lack of large proteomic datasets has restricted the identification of new cancer biomarkers. Here, proteomes of 949 cancer cell lines across 28 tissue types are analyzed by mass spectrometry. Deploying a workflow to quantify 8,498 proteins, these data capture evidence of cell-type and post-transcriptional modifications. Integrating multi-omics, drug response, and CRISPR-Cas9 gene essentiality screens with a deep learning-based pipeline reveals thousands of protein biomarkers of cancer vulnerabilities that are not significant at the transcript level. The power of the proteome to predict drug response is very similar to that of the transcriptome. Further, random downsampling to only 1,500 proteins has limited impact on predictive power, consistent with protein networks being highly connected and co-regulated. This pan-cancer proteomic map (ProCan-DepMapSanger) is a comprehensive resource available at https://cellmodelpassports.sanger.ac.uk.


Assuntos
Neoplasias , Proteômica , Biomarcadores Tumorais/genética , Linhagem Celular , Humanos , Neoplasias/genética , Proteoma/metabolismo , Proteômica/métodos
6.
Biomedicines ; 10(3)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35327410

RESUMO

Thyroid hormones have immunomodulatory roles, but their effects on the transcriptome and epigenome of innate immune cell types remain unexplored. In this study, we investigate the effects of triiodothyronine (T3) on the transcriptome and methylome of human monocytes in vitro, both in resting and lipopolysaccharide (LPS)-stimulated conditions. In resting monocytes, 5 µM T3 affected the expression of a small number of monocyte-to-macrophage differentiation-associated genes, including TLR4 (p-value < 0.05, expression fold change >1.5). T3 attenuated a small proportion of monocyte-to-macrophage differentiation-associated DNA methylation changes, while specifically inducing DNA methylation changes at several hundred differentially methylated CpG probes (DMPs) (p-value < 0.05, Δß > 0.05). In LPS-stimulated monocytes, the presence of T3 attenuated the effect of 27% of LPS-induced DMPs (p-value < 0.05, Δß > 0.05). Interestingly, co-stimulation with T3 + LPS induced a unique DNA methylation signature that was not observed in the LPS-only or T3-only exposure groups. Our results suggest that T3 induces limited transcriptional and DNA methylation remodeling in genes enriched in metabolism and immune processes and alters the normal in vitro LPS response. The overlap between differentially expressed genes and genes associated with DMPs was minimal; thus, other epigenetic mechanisms may underpin the expression changes. This research provides insight into the complex interplay between thyroid hormones, epigenetic remodeling, and transcriptional dynamics in monocytes.

7.
Clin Epigenetics ; 14(1): 24, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177097

RESUMO

BACKGROUND: DNA methylation is an epigenetic mark that is influenced by underlying genetic profile, environment, and ageing. In addition to X-linked DNA methylation, sex-specific methylation patterns are widespread across autosomal chromosomes and can be present from birth or arise over time. In individuals where gender identity and sex assigned at birth are markedly incongruent, as in the case of transgender people, feminization or masculinization may be sought through gender-affirming hormone therapy (GAHT). GAHT is a cornerstone of transgender care, yet no studies to date have investigated its effect on genome-wide methylation. We profiled genome-wide DNA methylation in blood of transgender women (n = 13) and transgender men (n = 13) before and during GAHT (6 months and 12 months into feminizing or masculinizing hormone therapy). RESULTS: We identified several thousand differentially methylated CpG sites (DMPs) (Δß ≥ 0.02, unadjusted p value < 0.05) and several differentially methylated regions (DMRs) in both people undergoing feminizing and masculinizing GAHT, the vast majority of which were progressive changes over time. X chromosome and sex-specific autosomal DNA methylation patterns established in early development are largely refractory to change in association with GAHT, with only 3% affected (Δß ≥ 0.02, unadjusted p value < 0.05). The small number of sex-specific DMPs that were affected by GAHT were those that become sex-specific during the lifetime, known as sex-and-age DMPs, including DMRs in PRR4 and VMP1 genes. The GAHT-induced changes at these sex-associated probes consistently demonstrated a shift towards the methylation signature of the GAHT-naïve opposite sex, and we observed enrichment of previously reported adolescence-associated methylation changes. CONCLUSION: We provide evidence for GAHT inducing a unique blood methylation signature in transgender people. This study advances our understanding of the complex interplay between sex hormones, sex chromosomes, and DNA methylation in the context of immunity. We highlight the need to broaden the field of 'sex-specific' immunity beyond cisgender males and cisgender females, as transgender people on GAHT exhibit a unique molecular profile.


Assuntos
Identidade de Gênero , Pessoas Transgênero , Metilação de DNA , Feminino , Hormônios , Humanos , Recém-Nascido , Masculino
8.
Front Immunol ; 12: 757393, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867995

RESUMO

Inflammatory memory involves the molecular and cellular 'reprogramming' of innate immune cells following exogenous stimuli, leading to non-specific protection against subsequent pathogen exposure. This phenomenon has now also been described in non-hematopoietic cells, such as human fetal and adult endothelial cells. In this study we mapped the cell-specific DNA methylation profile and the transcriptomic remodelling during the establishment of inflammatory memory in two distinct fetal endothelial cell types - a progenitor cell (ECFC) and a differentiated cell (HUVEC) population. We show that both cell types have a core transcriptional response to an initial exposure to a viral-like ligand, Poly(I:C), characterised by interferon responsive genes. There was also an ECFC specific response, marked by the transcription factor ELF1, suggesting a non-canonical viral response pathway in progenitor endothelial cells. Next, we show that both ECFCs and HUVECs establish memory in response to an initial viral exposure, resulting in an altered subsequent response to lipopolysaccharide. While the capacity to train or tolerize the induction of specific sets of genes was similar between the two cell types, the progenitor ECFCs show a higher capacity to establish memory. Among tolerized cellular pathways are those involved in endothelial barrier establishment and leukocyte migration, both important for regulating systemic immune-endothelial cell interactions. These findings suggest that the capacity for inflammatory memory may be a common trait across different endothelial cell types but also indicate that the specific downstream targets may vary by developmental stage.


Assuntos
Metilação de DNA , Células Progenitoras Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamação/patologia , Transcriptoma , Animais , Separação Celular , Células Cultivadas , Células Progenitoras Endoteliais/efeitos dos fármacos , Feto/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ontologia Genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Recém-Nascido , Inflamação/embriologia , Inflamação/genética , Inflamação/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Subfamília D de Receptores Semelhantes a Lectina de Células NK/biossíntese , Subfamília D de Receptores Semelhantes a Lectina de Células NK/genética , Proteínas Nucleares/metabolismo , Poli I-C/farmacologia , RNA/biossíntese , RNA/genética , Fatores de Transcrição/metabolismo
9.
Calcif Tissue Int ; 109(3): 291-302, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34417863

RESUMO

Osteoarthritis (OA) is one of the most prevalent conditions in the world, particularly in the developed world with a significant increase in cases and their predicted impact as we move through the twenty-first century and this will be exacerbated by the covid pandemic. The degeneration of cartilage and bone as part of this condition is becoming better understood but there are still significant challenges in painting a complete picture to recognise all aspects of the condition and what treatment(s) are most appropriate in individual causes. OA encompasses many different types and this causes some of the challenges in fully understanding the condition. There have been examples through history where much has been learnt about common disease(s) from the study of rare or extreme phenotypes, particularly where Mendelian disorders are involved. The often early onset of symptoms combined with the rapid and aggressive pathogenesis of these diseases and their predictable outcomes give an often-under-explored resource. It is these "rarer forms of disease" that William Harvey referred to that offer novel insights into more common conditions through their more extreme presentations. In the case of OA, GWAS analyses demonstrate the multiple genes that are implicated in OA in the general population. In some of these rarer forms, single defective genes are responsible. The extreme phenotypes seen in conditions such as Camptodactyly Arthropathy-Coxa Vara-pericarditis Syndrome, Chondrodysplasias and Alkaptonuria all present potential opportunities for greater understanding of disease pathogenesis, novel therapeutic interventions and diagnostic imaging. This review examines some of the rarer presenting forms of OA and linked conditions, some of the novel discoveries made whilst studying them, and findings on imaging and treatment strategies.


Assuntos
COVID-19 , Coxa Vara , Osteoartrite , Sinovite , Humanos , Osteoartrite/genética , SARS-CoV-2
10.
Nucleic Acids Res ; 49(D1): D1365-D1372, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33068406

RESUMO

CRISPR genetic screens in cancer cell models are a powerful tool to elucidate oncogenic mechanisms and to identify promising therapeutic targets. The Project Score database (https://score.depmap.sanger.ac.uk/) uses genome-wide CRISPR-Cas9 dropout screening data in hundreds of highly annotated cancer cell models to identify genes required for cell fitness and prioritize novel oncology targets. The Project Score database currently allows users to investigate the fitness effect of 18 009 genes tested across 323 cancer cell models. Through interactive interfaces, users can investigate data by selecting a specific gene, cancer cell model or tissue type, as well as browsing all gene fitness scores. Additionally, users can identify and rank candidate drug targets based on an established oncology target prioritization pipeline, incorporating genetic biomarkers and clinical datasets for each target, and including suitability for drug development based on pharmaceutical tractability. Data are freely available and downloadable. To enhance analyses, links to other key resources including Open Targets, COSMIC, the Cell Model Passports, UniProt and the Genomics of Drug Sensitivity in Cancer are provided. The Project Score database is a valuable new tool for investigating genetic dependencies in cancer cells and the identification of candidate oncology targets.


Assuntos
Biomarcadores Tumorais/genética , Bases de Dados Factuais , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Neoplasias/genética , Software , Antineoplásicos/uso terapêutico , Sistemas CRISPR-Cas , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Aptidão Genética , Humanos , Internet , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Oncogenes
11.
Dev Med Child Neurol ; 63(5): 560-565, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33332592

RESUMO

AIM: First, to understand the barriers to achieving effective transition and the supports required from the perspective of parents and carers, adolescents with intellectual disability and/or autism spectrum disorder and co-existing mental health disorders (often termed 'dual disability'), and those who provide services to this group. Second, to develop an informed model of shared care to improve the transition of adolescents with dual disabilities. METHOD: Carers and a young adult with a dual disability were surveyed about their experience of transition care. Other key stakeholders including paediatricians, general practitioners, and policy makers were also interviewed. These data informed the model of care. RESULTS: Paediatricians and general practitioners reported difficulties establishing working relationships to foster smooth transitions, and carers reported lacking a regular general practitioner with adequate expertise to care for people with dual disabilities. A process of shared care between paediatricians and general practitioners was developed and initiated by a dedicated transition manager, who assisted with care coordination and service linkages. Standardized clinical assessment tools were also introduced to determine patient and carer support needs. INTERPRETATION: This study highlights the potential to improve transition outcomes for adolescents with dual disabilities and their carers through early transition planning, consistent methods of assessing patient and carer needs, and shared care. WHAT THIS PAPER ADDS: Adolescents with co-occurring disabilities require a collaborative health and disability service interface. Fearless, Tearless Transition is a new approach to transitioning adolescents with dual disabilities from paediatric to adult care. Carers of adolescents with dual disabilities require support navigating and negotiating services. Engaging general practitioners and paediatricians in shared care early during the transition process is essential.


Assuntos
Transtorno do Espectro Autista/terapia , Deficiência Intelectual/terapia , Transtornos Mentais/complicações , Transição para Assistência do Adulto , Adolescente , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/psicologia , Cuidadores/psicologia , Pessoas com Deficiência , Pesquisas sobre Atenção à Saúde , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/psicologia , Transtornos Mentais/psicologia , Avaliação das Necessidades
12.
Nat Genet ; 52(11): 1189-1197, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32989322

RESUMO

Epidemiological studies have identified many environmental agents that appear to significantly increase cancer risk in human populations. By analyzing tumor genomes from mice chronically exposed to 1 of 20 known or suspected human carcinogens, we reveal that most agents do not generate distinct mutational signatures or increase mutation burden, with most mutations, including driver mutations, resulting from tissue-specific endogenous processes. We identify signatures resulting from exposure to cobalt and vinylidene chloride and link distinct human signatures (SBS19 and SBS42) with 1,2,3-trichloropropane, a haloalkane and pollutant of drinking water, and find these and other signatures in human tumor genomes. We define the cross-species genomic landscape of tumors induced by an important compendium of agents with relevance to human health.


Assuntos
Carcinógenos/toxicidade , Mutação , Animais , Carcinogênese/genética , Análise Mutacional de DNA , Poluentes Ambientais/toxicidade , Feminino , Genoma , Humanos , Masculino , Camundongos , Taxa de Mutação , Propano/análogos & derivados , Propano/toxicidade , Especificidade da Espécie
13.
iScience ; 23(6): 101171, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32480123

RESUMO

The prevalence of IgE-mediated food allergy is increasing at a rapid pace in many countries. The association of high food allergy rates with Westernized lifestyles suggests the role of gene-environment interactions, potentially underpinned by epigenetic variation, in mediating this process. Recent studies have implicated innate immune system dysfunction in the development and persistence of food allergy. These responses are characterized by increased circulating frequency of innate immune cells and heightened inflammatory responses to bacterial stimulation in food allergic patients. These signatures mirror those described in trained immunity, whereby innate immune cells retain a "memory" of earlier microbial encounters, thus influencing subsequent immune responses. Here, we propose that a robust multi-omics approach that integrates immunological, transcriptomic, and epigenomic datasets, combined with well-phenotyped and longitudinal food allergy cohorts, can inform the potential role of trained immunity in food allergy.

14.
Front Immunol ; 11: 604000, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33584674

RESUMO

Sexual dimorphism refers to differences between biological sexes that extend beyond sexual characteristics. In humans, sexual dimorphism in the immune response has been well demonstrated, with females exhibiting lower infection rates than males for a variety of bacterial, viral, and parasitic pathogens. There is also a substantially increased incidence of autoimmune disease in females compared to males. Together, these trends indicate that females have a heightened immune reactogenicity to both self and non-self-molecular patterns. However, the molecular mechanisms driving the sexually dimorphic immune response are not fully understood. The female sex hormones estrogen and progesterone, as well as the male androgens, such as testosterone, elicit direct effects on the function and inflammatory capacity of immune cells. Several studies have identified a sex-specific transcriptome and methylome, independent of the well-described phenomenon of X-chromosome inactivation, suggesting that sexual dimorphism also occurs at the epigenetic level. Moreover, distinct alterations to the transcriptome and epigenetic landscape occur in synchrony with periods of hormonal change, such as puberty, pregnancy, menopause, and exogenous hormone therapy. These changes are also mirrored by changes in immune cell function. This review will outline the evidence for sex hormones and pregnancy-associated hormones as drivers of epigenetic change, and how this may contribute to the sexual dimorphism. Determining the effects of sex hormones on innate immune function is important for understanding sexually dimorphic autoimmune diseases, sex-specific responses to pathogens and vaccines, and how innate immunity is altered during periods of hormonal change (endogenous or exogenous).


Assuntos
Epigênese Genética , Epigenoma , Hormônios Esteroides Gonadais/metabolismo , Imunidade Inata , Caracteres Sexuais , Fatores Etários , Animais , Autoimunidade , Terapia de Reposição de Estrogênios , Estrogênios/metabolismo , Feminino , Hormônios Esteroides Gonadais/uso terapêutico , Humanos , Imunidade Inata/efeitos dos fármacos , Masculino , Progesterona/metabolismo , Fatores Sexuais , Desenvolvimento Sexual , Testosterona/metabolismo
15.
Nat Commun ; 10(1): 5817, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862961

RESUMO

Genome-scale CRISPR-Cas9 viability screens performed in cancer cell lines provide a systematic approach to identify cancer dependencies and new therapeutic targets. As multiple large-scale screens become available, a formal assessment of the reproducibility of these experiments becomes necessary. We analyze data from recently published pan-cancer CRISPR-Cas9 screens performed at the Broad and Sanger Institutes. Despite significant differences in experimental protocols and reagents, we find that the screen results are highly concordant across multiple metrics with both common and specific dependencies jointly identified across the two studies. Furthermore, robust biomarkers of gene dependency found in one data set are recovered in the other. Through further analysis and replication experiments at each institute, we show that batch effects are driven principally by two key experimental parameters: the reagent library and the assay length. These results indicate that the Broad and Sanger CRISPR-Cas9 viability screens yield robust and reproducible findings.


Assuntos
Biomarcadores Tumorais/genética , Sistemas CRISPR-Cas/genética , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Genômica/métodos , Neoplasias/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Genes Essenciais/efeitos dos fármacos , Genes Essenciais/genética , Humanos , Terapia de Alvo Molecular/métodos , Neoplasias/tratamento farmacológico , Oncogenes/efeitos dos fármacos , Oncogenes/genética , Medicina de Precisão/métodos , Reprodutibilidade dos Testes , Bibliotecas de Moléculas Pequenas/farmacologia
16.
BMC Genomics ; 19(1): 604, 2018 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-30103702

RESUMO

BACKGROUND: Genome editing by CRISPR-Cas9 technology allows large-scale screening of gene essentiality in cancer. A confounding factor when interpreting CRISPR-Cas9 screens is the high false-positive rate in detecting essential genes within copy number amplified regions of the genome. We have developed the computational tool CRISPRcleanR which is capable of identifying and correcting gene-independent responses to CRISPR-Cas9 targeting. CRISPRcleanR uses an unsupervised approach based on the segmentation of single-guide RNA fold change values across the genome, without making any assumption about the copy number status of the targeted genes. RESULTS: Applying our method to existing and newly generated genome-wide essentiality profiles from 15 cancer cell lines, we demonstrate that CRISPRcleanR reduces false positives when calling essential genes, correcting biases within and outside of amplified regions, while maintaining true positive rates. Established cancer dependencies and essentiality signals of amplified cancer driver genes are detectable post-correction. CRISPRcleanR reports sgRNA fold changes and normalised read counts, is therefore compatible with downstream analysis tools, and works with multiple sgRNA libraries. CONCLUSIONS: CRISPRcleanR is a versatile open-source tool for the analysis of CRISPR-Cas9 knockout screens to identify essential genes.


Assuntos
Sistemas CRISPR-Cas , Marcação de Genes/métodos , Genoma Humano , Neoplasias/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Amplificação de Genes , Técnicas de Inativação de Genes/métodos , Genes Essenciais , Ensaios de Triagem em Larga Escala , Humanos , Análise de Sequência de DNA , Software
17.
Nat Commun ; 7: 12605, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27615322

RESUMO

Ionizing radiation is a potent carcinogen, inducing cancer through DNA damage. The signatures of mutations arising in human tissues following in vivo exposure to ionizing radiation have not been documented. Here, we searched for signatures of ionizing radiation in 12 radiation-associated second malignancies of different tumour types. Two signatures of somatic mutation characterize ionizing radiation exposure irrespective of tumour type. Compared with 319 radiation-naive tumours, radiation-associated tumours carry a median extra 201 deletions genome-wide, sized 1-100 base pairs often with microhomology at the junction. Unlike deletions of radiation-naive tumours, these show no variation in density across the genome or correlation with sequence context, replication timing or chromatin structure. Furthermore, we observe a significant increase in balanced inversions in radiation-associated tumours. Both small deletions and inversions generate driver mutations. Thus, ionizing radiation generates distinctive mutational signatures that explain its carcinogenic potential.


Assuntos
Segunda Neoplasia Primária , Radiação Ionizante , Neoplasias da Mama , Dano ao DNA , Feminino , Deleção de Genes , Mutação em Linhagem Germinativa , Humanos , Masculino , Mutação , Osteossarcoma , Neoplasias da Próstata
18.
Women Birth ; 29(2): 189-95, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26563638

RESUMO

BACKGROUND: The prevalence of overweight and obesity is increasing amongst women of child bearing age. Maternal obesity has implications for both mother and baby including increased health risks from gestational hypertensive disorders, caesarean section and stillbirth. Despite the increasing prevalence of maternal obesity little is known of the experiences of these women within the health care system. The aim of this research was to investigate the perspectives of pregnant women with a body mass index (BMI) of ≥30kg/m(2) receiving antenatal care. METHODS: A qualitative study using individual interviews was undertaken. Sixteen pregnant women with a BMI ≥30kg/m(2) participated. Interviews were audio recorded, transcribed, cross checked for consistency and then entered into a word processing document for analysis. Data was analysed using Interpretative Phenomenological Analysis. In any phenomenological study the researcher's objective is to elicit the participant's views on their lived experiences. FINDINGS: Four major themes emerged: (1) obese during pregnancy as part of a long history of obesity; (2) lack of knowledge of the key complications of obesity for both mother and child; (3) communication about weight and gestational weight gain can be conflicting, confusing and judgmental; (4) most women are motivated to eat well during pregnancy and want help to do so. CONCLUSION: Specialist lifestyle interventions for obese women should be a priority in antenatal care. Extra support is required to assist obese women in pregnancy achieve recommended nutritional and weight goals. Health professionals should approach the issue of maternal obesity in an informative but non-judgmental way.


Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Obesidade/complicações , Complicações na Gravidez/prevenção & controle , Relações Profissional-Paciente , Adulto , Índice de Massa Corporal , Aconselhamento , Feminino , Humanos , Lactente , Entrevistas como Assunto , Estilo de Vida , Mães , Obesidade/psicologia , Gravidez , Cuidado Pré-Natal/métodos , Pesquisa Qualitativa
19.
Nat Commun ; 6: 10001, 2015 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-26647970

RESUMO

As whole-genome sequencing for cancer genome analysis becomes a clinical tool, a full understanding of the variables affecting sequencing analysis output is required. Here using tumour-normal sample pairs from two different types of cancer, chronic lymphocytic leukaemia and medulloblastoma, we conduct a benchmarking exercise within the context of the International Cancer Genome Consortium. We compare sequencing methods, analysis pipelines and validation methods. We show that using PCR-free methods and increasing sequencing depth to ∼ 100 × shows benefits, as long as the tumour:control coverage ratio remains balanced. We observe widely varying mutation call rates and low concordance among analysis pipelines, reflecting the artefact-prone nature of the raw data and lack of standards for dealing with the artefacts. However, we show that, using the benchmark mutation set we have created, many issues are in fact easy to remedy and have an immediate positive impact on mutation detection accuracy.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leucemia Linfoide/genética , Meduloblastoma/genética , Mutação , Genoma Humano , Humanos
20.
Database (Oxford) ; 2011: bar041, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21930507

RESUMO

BioMart Central Portal is a first of its kind, community-driven effort to provide unified access to dozens of biological databases spanning genomics, proteomics, model organisms, cancer data, ontology information and more. Anybody can contribute an independently maintained resource to the Central Portal, allowing it to be exposed to and shared with the research community, and linking it with the other resources in the portal. Users can take advantage of the common interface to quickly utilize different sources without learning a new system for each. The system also simplifies cross-database searches that might otherwise require several complicated steps. Several integrated tools streamline common tasks, such as converting between ID formats and retrieving sequences. The combination of a wide variety of databases, an easy-to-use interface, robust programmatic access and the array of tools make Central Portal a one-stop shop for biological data querying. Here, we describe the structure of Central Portal and show example queries to demonstrate its capabilities.


Assuntos
Pesquisa Biomédica , Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Internet , Animais , Bactérias , Fungos , Genoma , Humanos , Cooperação Internacional , Interface Usuário-Computador , Vírus
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