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1.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35553695

RESUMO

During development, melanocytes undergo a series of cellular and metabolic changes in order to reach a terminally differentiated state. Some of these changes include extensive proliferation, formation of dendritic projections from the cell membrane, and melanin synthesis. Each of these processes is likely to create distinct metabolic needs, however, little work has been done to investigate how the differentiating melanocyte meets these requirements. Previous work in our lab identified that stromal mesenchymal adipocytes are donors of lipids that aids in melanoma progression and metastasis. This raises the question of whether fatty acid metabolism might also play a role in melanocyte development. Additionally, it indicates a need for further investigation into the role of cellular metabolism in both melanocyte differentiation and related diseases. Herein, we performed a chemical screen as a discovery approach using the Sigma Aldrich LOPAC library containing 1280 compounds in T5D zebrafish embryos and validate the primary hits via titration at different developmental time points. Treatment was initiated at 24-hour post fertilization for a 48-hour period at a 10 µM concentration. With this screen we identified a total of fifty compounds which affected melanocyte growth, development, migration pattern, and/or phenotypic appearance in the context of a complete developing organism allowing a more comprehensive analysis. Preliminary data suggest that different pathways such as T-Cell Receptor inhibition, nitric oxide donors and/or sequesters, inhibition of inflammatory responses from macrophages, basophils and mast cells can potentially affect melanocyte development. Together, these findings help us to better understand the details of melanocyte development and further characterization of these pathways will greatly enhance our understanding of the metabolic requirements of these processes and could yield insight into the role of these processes in melanoma and other disease contexts.

2.
Front Pharmacol ; 13: 893655, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35559262

RESUMO

In the last decade, zebrafish have accompanied the mouse as a robust animal model for cancer research. The possibility of screening small-molecule inhibitors in a large number of zebrafish embryos makes this model particularly valuable. However, the dynamic visualization of fluorescently labeled tumor cells needs to be complemented by a more sensitive, easy, and rapid mode for evaluating tumor growth in vivo to enable high-throughput screening of clinically relevant drugs. In this study we proposed and validated a pre-clinical screening model for drug discovery by utilizing bioluminescence as our readout for the determination of transplanted cancer cell growth and inhibition in zebrafish embryos. For this purpose, we used NanoLuc luciferase, which ensured rapid cancer cell growth quantification in vivo with high sensitivity and low background when compared to conventional fluorescence measurements. This allowed us large-scale evaluation of in vivo drug responses of 180 kinase inhibitors in zebrafish. Our bioluminescent screening platform could facilitate identification of new small-molecules for targeted cancer therapy as well as for drug repurposing.

3.
Dis Model Mech ; 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35514229

RESUMO

Manganese neurotoxicity is a hallmark of Hypermanganesemia with Dystonia 2, an inherited manganese transporter defect caused by mutations in SLC39A14. To identify novel potential targets of manganese neurotoxicity we performed transcriptome analysis of slc39a14-/- mutant zebrafish unexposed and exposed to MnCl2. Differentially expressed genes mapped to the central nervous system and eye, and pathway analysis suggested that calcium dyshomeostasis and activation of the unfolded protein response are key features of manganese neurotoxicity. Consistent with this interpretation, MnCl2 exposure led to decreased whole animal calcium levels, locomotor defects and changes in neuronal activity within the telencephalon and optic tectum. In accordance with reduced tectal activity, slc39a14-/- zebrafish showed changes in visual phototransduction gene expression, absence of visual background adaptation and a diminished optokinetic reflex. Finally, numerous differentially expressed genes in mutant larvae normalised upon MnCl2 treatment indicating that, in addition to neurotoxicity, manganese deficiency is present either subcellularly or in specific cells or tissues. Overall, we assembled a comprehensive set of genes that mediate manganese-systemic responses and found a highly correlated and modulated network associated with calcium dyshomeostasis and cellular stress.

4.
Antimicrob Agents Chemother ; : e0179021, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35435707

RESUMO

Multidrug-resistant (MDR) Pseudomonas aeruginosa infections are a major clinical challenge. Many isolates are carbapenem resistant, which severely limits treatment options; thus, novel therapeutic combinations, such as imipenem-relebactam (IMI/REL), ceftazidime-avibactam (CAZ/AVI), ceftolozane-tazobactam (TOL/TAZO), and meropenem-vaborbactam (MEM/VAB) were developed. Here, we studied two extensively drug-resistant (XDR) P. aeruginosa isolates, collected in the United States and Mexico, that demonstrated resistance to IMI/REL. Whole-genome sequencing (WGS) showed that both isolates contained acquired GES ß-lactamases, intrinsic PDC and OXA ß-lactamases, and disruptions in the genes encoding the OprD porin, thereby inhibiting uptake of carbapenems. In one isolate (ST17), the entire C terminus of OprD deviated from the expected amino acid sequence after amino acid G388. In the other (ST309), the entire oprD gene was interrupted by an ISPa1328 insertion element after amino acid D43, rendering this porin nonfunctional. The poor inhibition by REL of the GES ß-lactamases (GES-2, -19, and -20; apparent Ki of 19 ± 2 µM, 23 ± 2 µM, and 21 ± 2 µM, respectively) within the isolates also contributed to the observed IMI/REL-resistant phenotype. Modeling of REL binding to the active site of GES-20 suggested that the acylated REL is positioned in an unstable conformation as a result of a constrained Ω-loop.

5.
J Surg Oncol ; 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35411951

RESUMO

INTRODUCTION: Co-surgeon approach for bilateral mastectomy may lead to shorter operative times and improved outcomes compared with single-surgeon approach, but cost differences remain unclear. Economic models were applied to determine whether either approach offered a lower cost opportunity. METHODS: A retrospective review of 409 patients undergoing single-surgeon or co-surgeon bilateral mastectomy between January 1, 2010 through April 30, 2016 was conducted. Outcomes included narcotic and antinausea doses, length of stay (LOS), and operative time. Analyses stratified by reconstruction and no reconstruction included Wilcoxon tests, Poisson regression, generalized linear models, and a cost calculator. RESULTS: Of 409 patients, 310 had reconstruction and 99 had no reconstruction. Compared with single-surgeon approach, co-surgeon approach was associated with less operative time and shorter LOS (233 vs. 250 min and 1.0 vs. 1.8 days no reconstruction; and 429 vs. 493 min and 2.2 vs. 2.8 days reconstruction). Economic analysis demonstrated less operative time, shorter LOS, and lower average cost for co-surgeon approach ($32,400 vs. $34,400 no reconstruction; and $76,700 vs. $79,400 reconstruction). CONCLUSION: Compared with the single-surgeon, the co-surgeon approach with reconstruction was associated with a statistically significant decrease in operative time and LOS. Economic analysis estimated the co-surgeon approach could lead to lower costs.

6.
BMJ Glob Health ; 7(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35396264

RESUMO

BACKGROUND: There is a high risk of Mycobacterium tuberculosis (Mtb) transmission in healthcare facilities in high burden settings. WHO guidelines on tuberculosis (TB) infection prevention and control (IPC) recommend a range of measures to reduce transmission in healthcare settings. These were evaluated primarily based on evidence for their effects on transmission to healthcare workers in hospitals. To estimate the overall impact of IPC interventions, it is necessary to also consider their impact on community-wide TB incidence and mortality. METHODS: We developed an individual-based model of Mtb transmission in households, primary healthcare (PHC) clinics, and all other congregate settings. The model was parameterised using data from a high HIV prevalence community in South Africa, including data on social contact by setting, by sex, age, and HIV/antiretroviral therapy status; and data on TB prevalence in clinic attendees and the general population. We estimated the proportion of disease in adults that resulted from transmission in PHC clinics, and the impact of a range of IPC interventions in clinics on community-wide TB. RESULTS: We estimate that 7.6% (plausible range 3.9%-13.9%) of non-multidrug resistant and multidrug resistant TB in adults resulted directly from transmission in PHC clinics in the community in 2019. The proportion is higher in HIV-positive people, at 9.3% (4.8%-16.8%), compared with 5.3% (2.7%-10.1%) in HIV-negative people. We estimate that IPC interventions could reduce incident TB cases in the community in 2021-2030 by 3.4%-8.0%, and deaths by 3.0%-7.2%. CONCLUSIONS: A non-trivial proportion of TB results from transmission in clinics in the study community, particularly in HIV-positive people. Implementing IPC interventions could lead to moderate reductions in disease burden. We recommend that IPC measures in clinics should be implemented for their benefits to staff and patients, but also for their likely effects on TB incidence and mortality in the surrounding community.


Assuntos
Infecções por HIV , Tuberculose , Adulto , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Incidência , Atenção Primária à Saúde , África do Sul/epidemiologia , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
7.
PLoS Comput Biol ; 18(4): e1010002, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35452459

RESUMO

We investigated the effects of updating age-specific social contact matrices to match evolving demography on vaccine impact estimates. We used a dynamic transmission model of tuberculosis in India as a case study. We modelled four incremental methods to update contact matrices over time, where each method incorporated its predecessor: fixed contact matrix (M0), preserved contact reciprocity (M1), preserved contact assortativity (M2), and preserved average contacts per individual (M3). We updated the contact matrices of a deterministic compartmental model of tuberculosis transmission, calibrated to epidemiologic data between 2000 and 2019 derived from India. We additionally calibrated the M0, M2, and M3 models to the 2050 TB incidence rate projected by the calibrated M1 model. We stratified age into three groups, children (<15y), adults (≥15y, <65y), and the elderly (≥65y), using World Population Prospects demographic data, between which we applied POLYMOD-derived social contact matrices. We simulated an M72-AS01E-like tuberculosis vaccine delivered from 2027 and estimated the per cent TB incidence rate reduction (IRR) in 2050 under each update method. We found that vaccine impact estimates in all age groups remained relatively stable between the M0-M3 models, irrespective of vaccine-targeting by age group. The maximum difference in impact, observed following adult-targeted vaccination, was 7% in the elderly, in whom we observed IRRs of 19% (uncertainty range 13-32), 20% (UR 13-31), 22% (UR 14-37), and 26% (UR 18-38) following M0, M1, M2 and M3 updates, respectively. We found that model-based TB vaccine impact estimates were relatively insensitive to demography-matched contact matrix updates in an India-like demographic and epidemiologic scenario. Current model-based TB vaccine impact estimates may be reasonably robust to the lack of contact matrix updates, but further research is needed to confirm and generalise this finding.


Assuntos
Tuberculose , Adulto , Fatores Etários , Idoso , Criança , Humanos , Incidência , Modelos Teóricos , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Vacinação
9.
Nature ; 604(7905): 354-361, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35355015

RESUMO

Oncogenic alterations to DNA are not transforming in all cellular contexts1,2. This may be due to pre-existing transcriptional programmes in the cell of origin. Here we define anatomic position as a major determinant of why cells respond to specific oncogenes. Cutaneous melanoma arises throughout the body, whereas the acral subtype arises on the palms of the hands, soles of the feet or under the nails3. We sequenced the DNA of cutaneous and acral melanomas from a large cohort of human patients and found a specific enrichment for BRAF mutations in cutaneous melanoma and enrichment for CRKL amplifications in acral melanoma. We modelled these changes in transgenic zebrafish models and found that CRKL-driven tumours formed predominantly in the fins of the fish. The fins are the evolutionary precursors to tetrapod limbs, indicating that melanocytes in these acral locations may be uniquely susceptible to CRKL. RNA profiling of these fin and limb melanocytes, when compared with body melanocytes, revealed a positional identity gene programme typified by posterior HOX13 genes. This positional gene programme synergized with CRKL to amplify insulin-like growth factor (IGF) signalling and drive tumours at acral sites. Abrogation of this CRKL-driven programme eliminated the anatomic specificity of acral melanoma. These data suggest that the anatomic position of the cell of origin endows it with a unique transcriptional state that makes it susceptible to only certain oncogenic insults.


Assuntos
Melanoma , Neoplasias Cutâneas , Animais , Animais Geneticamente Modificados , Carcinogênese/genética , , Mãos , Humanos , Melanoma/patologia , Unhas , Oncogenes/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Transcrição Genética , Peixe-Zebra/genética
10.
Bio Protoc ; 12(1): e4284, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35118175

RESUMO

RNA sequencing allows for the quantification of the transcriptome of embryos to investigate transcriptional responses to various perturbations (e.g., mutations, infections, drug treatments). Previous protocols either lack the option to genotype individual samples, or are laborious and therefore difficult to do at a large scale. We have developed a protocol to extract total nucleic acid from individual zebrafish embryos. Individual embryos are lysed in 96-well plates and nucleic acid is extracted using SPRI beads. The total nucleic acid can be genotyped and then DNase I treated to produce RNA samples for sequencing. This protocol allows for processing large numbers of individual samples, with the ability to genotype each sample, which makes it possible to undertake transcriptomic analysis on mutants at timepoints before the phenotype is visible. Graphic abstract: Extraction of total nucleic acid from individual zebrafish embryos for genotyping and RNA-seq.

11.
Vaccine ; 40(12): 1681-1690, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35164990

RESUMO

Currently, no formal mechanisms or systematic approaches exist to inform developers of new vaccines of the evidence anticipated to facilitate global policy recommendations, before a vaccine candidate approaches regulatory approval at the end of pre-licensure efficacy studies. Consequently, significant delays may result in vaccine introduction and uptake, while post-licensure data are generated to support a definitive policy decision. To address the uncertainties of the evidence-to-recommendation data needs and to mitigate the risk of delays between vaccine recommendation and use, WHO is evaluating the need for and value of a new strategic alignment tool: Evidence Considerations for Vaccine Policy (ECVP). EVCPs aim to fill a critical current gap by providing early (pre-phase 3 study design) information on the anticipated clinical trial and observational data or evidence that could support WHO and/or policy decision making for new vaccines in priority disease areas. The intent of ECVPs is to inform vaccine developers, funders, and other key stakeholders, facilitating stakeholder alignment in their strategic planning for late stage vaccine development. While ECVPs are envisaged as a tool to support dialogue on evidence needs between regulators and policy makers at the national, regional and global level, development of an ECVP will not preclude or supersede the independent WHO's Strategic Advisory Group of Experts on Immunization (SAGE) evidence to recommendation (EtR) process that is required for all vaccines seeking WHO policy recommendation. Tuberculosis (TB) vaccine candidates intended for use in the adolescent and adult target populations comprise a portfolio of priority vaccines in late-stage clinical development. As such, TB vaccines intended for use in this target population provide a 'test case' to further develop the ECVP concept, and develop the first WHO ECVP considerations guidance.


Assuntos
Vacinas contra a Tuberculose , Adolescente , Humanos , Programas de Imunização , Políticas , Vacinação , Organização Mundial da Saúde
12.
Nat Commun ; 13(1): 602, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35105879

RESUMO

The M72/AS01E tuberculosis vaccine showed 50% (95%CI: 2-74%) efficacy in a phase 2B trial in preventing active pulmonary tuberculosis disease, but potential cost-effectiveness of adolescent immunisation is unknown. We estimated the impact and cost-effectiveness of six scenarios of routine adolescent M72/AS01E-like vaccination in South Africa and India. All scenarios suggested an M72/AS01E-like vaccine would be highly (94-100%) cost-effective in South Africa compared to a cost-effectiveness threshold of $2480/disability-adjusted life-year (DALY) averted. For India, a prevention of disease vaccine, effective irrespective of recipient's M. tuberculosis infection status at time of administration, was also highly likely (92-100%) cost-effective at a threshold of $264/DALY averted; however, a prevention of disease vaccine, effective only if the recipient was already infected, had 0-6% probability of cost-effectiveness. In both settings, vaccinating 50% of 18 year-olds was similarly cost-effective to vaccinating 80% of 15 year-olds, and more cost-effective than vaccinating 80% of 10 year-olds. Vaccine trials should include adolescents to ensure vaccines can be delivered to this efficient-to-target population.


Assuntos
Análise Custo-Benefício , Vacinas contra a Tuberculose/imunologia , Vacinação/economia , Adolescente , Custos e Análise de Custo , Humanos , Índia , Mycobacterium tuberculosis/imunologia , África do Sul , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
13.
Artigo em Inglês | MEDLINE | ID: mdl-35065848

RESUMO

PURPOSE: TARGIT-A was a pragmatic randomized noninferiority trial including women with early-stage breast cancer treated postlumpectomy with either external beam radiation therapy (EBRT) or 50 kV x-rays delivered intraoperatively with or without EBRT, as indicated. The long-term update of the pre-pathology cohort did not include a 10-year estimate of the primary endpoint of local failure (although tabular 5-year data was provided). Here, we used the data from the pre-pathology manuscript to estimate the cumulative incidence of local failure. METHODS AND MATERIALS: Using digitizer software and the published survival curves, we extracted the Kaplan-Meier rate of local recurrence-free survival and overall survival. The extracted data were calibrated to the published point-estimates to within ±0.5%. The data were then fit to parametric survival models, and overall survival and local recurrence-free survival curves were subtracted to give the estimate of local failure in the presence of the competing risk of death. Bootstrap resampling was used to assess for parameter uncertainty in the modeling process. RESULTS: Our analysis estimated that the risk of local failure at 10 years in the TARGIT-A pre-pathology cohort is approximately 1.7% with EBRT (95% confidence interval [CI], 0%-4.3%) and 5.5% in the pragmatic risk-adapted TARGIT strategy (95% CI, 2.9%-8.0%). A weighted average estimate suggests that the risk of local failure in low-risk women treated with TARGIT alone is approximately 6.6% at 10 years (95% CI, 3.3%-10.0%), with an estimated difference of 4.9% (95% CI, 0.6%-9.2%) compared with EBRT. CONCLUSIONS: These data allow for contextualization and informed decisions when considering megavoltage EBRT, kilovoltage intraoperatively, or omission of radiation therapy entirely.

14.
Thromb Haemost ; 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35038763

RESUMO

INTRODUCTION: The epidemiology of isolated distal deep venous thrombosis (iDDVT) among cancer patients is not well described, particularly the incidence of recurrent venous thromboembolism (rVTE) and effect on mortality by cancer type. METHODS: The cumulative incidence (CI) of iDDVT was determined for patients with 13 common cancers between 2005 and 2017 using the California Cancer Registry linked to the California Patient Discharge and Emergency Department Utilization datasets. The CI of rVTE was calculated and association of incident cancer-associated thrombosis (CT) location with rVTE was determined using Cox proportional hazards regression models. The association of incident CT location with overall and cancer-specific mortality was determined using Cox models, stratified by cancer site, and adjusted for individual characteristics. RESULTS: Among 942,109 cancer patients, CT occurred in 62,003 (6.6%): of these, 6,841 (11.0%) were iDDVT. Compared with more proximal sites of CT, iDDVT was associated with similar risk for rVTE. IDDVT was associated with increased mortality across all cancer types when compared with patients without CT (hazard ratio: 1.56-4.60). The effect of iDDVT on mortality was similar to that of proximal DVT (pDVT) for most cancers except lung, colorectal, bladder, uterine, brain, and myeloma, where iDDVT was associated with a lesser association with mortality. CONCLUSION: iDDVT represented 11% of CT. The risk of rVTE after iDDVT was similar to other sites of CT and rVTE occurred in more proximal locations after an incident iDDVT. IDDVT was associated with increased mortality and this effect was similar to that of pulmonary embolism or pDVT for most cancer types.

15.
J Surg Oncol ; 125(2): 229-238, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34535899

RESUMO

BACKGROUND AND OBJECTIVES: The prognostic significance of regression in predicting melanoma recurrences is unknown. We present a large multicenter study correlating regression with recurrence. METHODS: The Sentinel Lymph Node Working Group database was queried from 1993 to 2018 for cases with regression data. Clinicopathologic factors were correlated with overall and first-site of recurrence and with recurrence-free survival (RFS). RESULTS: There were 4790 patients and the median follow-up was 39.6 months. Regression and recurrences were seen in 1081 (22.6%) and 773 (16.1%) cases, respectively. First-site locoregional and distant recurrences were seen in 412 (8.6%) and 352 (7.3%) patients, respectively. Regression was seen in 15.8% and 24.7% of all cases with and without recurrences (p < 0.0001), respectively, while regression was seen in 14.3% and 17.9% of first-site locoregional and distant recurrent cases, respectively, compared with 23.3% and 22.9% of patients with regression and without first-site locoregional and distant recurrences, respectively (p = 0.29). On multivariable analysis, after controlling for age, gender, thickness, ulceration, lymphovascular invasion, and sentinel lymph node status, regression significantly predicted improved RFS (p = 0.004) and fewer first-site regional recurrences (p = 0.017). CONCLUSION: Our data suggest that regression is a favorable prognostic marker in melanoma and predicts significantly better RFS and decreased first-site regional recurrences.


Assuntos
Melanoma/mortalidade , Recidiva Local de Neoplasia/epidemiologia , Idoso , Feminino , Humanos , Metástase Linfática , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Linfonodo Sentinela/patologia , Linfonodo Sentinela/cirurgia
16.
Elife ; 112022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35175196

RESUMO

In model organisms, RNA-sequencing (RNA-seq) is frequently used to assess the effect of genetic mutations on cellular and developmental processes. Typically, animals heterozygous for a mutation are crossed to produce offspring with different genotypes. Resultant embryos are grouped by genotype to compare homozygous mutant embryos to heterozygous and wild-type siblings. Genes that are differentially expressed between the groups are assumed to reveal insights into the pathways affected by the mutation. Here we show that in zebrafish, differentially expressed genes are often over-represented on the same chromosome as the mutation due to different levels of expression of alleles from different genetic backgrounds. Using an incross of haplotype-resolved wild-type fish, we found evidence of widespread allele-specific expression, which appears as differential expression when comparing embryos homozygous for a region of the genome to their siblings. When analysing mutant transcriptomes, this means that the differential expression of genes on the same chromosome as a mutation of interest may not be caused by that mutation. Typically, the genomic location of a differentially expressed gene is not considered when interpreting its importance with respect to the phenotype. This could lead to pathways being erroneously implicated or overlooked due to the noise of spurious differentially expressed genes on the same chromosome as the mutation. These observations have implications for the interpretation of RNA-seq experiments involving outbred animals and non-inbred model organisms.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Alelos , Animais , Expressão Gênica , Heterozigoto , Mutação , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
17.
Ann N Y Acad Sci ; 1506(1): 142-163, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34850398

RESUMO

The test for the cancer stem cell (CSC) hypothesis is to find a target expressed on all, and only CSCs in a patient tumor, then eliminate all cells with that target that eliminates the cancer. That test has not yet been achieved, but CSC diagnostics and targets found on CSCs and some other cells have resulted in a few clinically relevant therapies. However, it has become apparent that eliminating the subset of tumor cells characterized by self-renewal properties is essential for long-term tumor control. CSCs are able to regenerate and initiate tumor growth, recapitulating the heterogeneity present in the tumor before treatment. As great progress has been made in identifying and elucidating the biology of CSCs as well as their interactions with the tumor microenvironment, the time seems ripe for novel therapeutic strategies that target CSCs to find clinical applicability. On May 19-21, 2021, researchers in cancer stem cells met virtually for the Keystone eSymposium "Cancer Stem Cells: Advances in Biology and Clinical Translation" to discuss recent advances in the understanding of CSCs as well as clinical efforts to target these populations.


Assuntos
Congressos como Assunto/tendências , Neoplasias/genética , Células-Tronco Neoplásicas/fisiologia , Relatório de Pesquisa , Microambiente Tumoral/fisiologia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Neoplasias/metabolismo , /métodos
18.
BMJ Open ; 11(12): e047136, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907038

RESUMO

OBJECTIVES: Selected Zambian communities formed part of a cluster randomised trial: the Zambia and South Africa TB and AIDS Reduction study (ZAMSTAR). There was wide variability in the prevalence of Mycobacterium tuberculosis infection and tuberculosis (TB) disease across these communities. We sought to clarify whether specific communities could have been more/less vulnerable to M. tuberculosis transmission as a result of sociological variety relevant to transmission efficiency. DESIGN: We conducted a mixed methods secondary analysis using existing data sets. First, we analysed qualitative data to categorise and synthesise patterns of socio-spatial engagement across communities. Second, we compared emergent sociological variables with a measure of transmission efficiency: the ratio of the annual risk of infection to TB prevalence. SETTING: ZAMSTAR communities in urban and peri-urban Zambia, spanning five provinces. PARTICIPANTS: Fifteen communities, each served by a health facility offering TB treatment to a population of at least 25 000. TB notification rates were at least 400 per 100 000 per annum and HIV seroprevalence was estimated to be high. RESULTS: Crowding, movement, livelihoods and participation in recreational activity differed across communities. Based on 12 socio-spatial indicators, communities were qualitatively classified as more/less spatially crowded and as more/less socially 'open' to contact with others, with implications for the presumptive risk of M. tuberculosis transmission. For example, watching video shows in poorly ventilated structures posed a presumptive risk in more socially open communities, while outdoor farming and/or fishing were particularly widespread in communities with lower transmission measures. CONCLUSIONS: A dual dynamic of 'social permeability' and crowding appeared relevant to disparities in M. tuberculosis transmission efficiency. To reduce transmission, certain socio-spatial aspects could be adjusted (eg, increasing ventilation on transport), while more structural aspects are less malleable (eg, reliance on public transport). We recommend integrating community level typologies with genome sequencing techniques to further explore the significance of 'social permeability'. TRIAL REGISTRATION NUMBER: ISRCTN36729271.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Infecções por HIV/complicações , Humanos , Estudos Soroepidemiológicos , Tuberculose/complicações , Zâmbia/epidemiologia
19.
Vaccines (Basel) ; 9(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34835161

RESUMO

The impact of COVID-19 disruptions on global Bacillus Calmette-Guérin (BCG) coverage and paediatric tuberculosis (TB) mortality is still unknown. To fill this evidence-gap and guide mitigation measures, we estimated the impact of COVID-19 disruptions on global BCG coverage and paediatric TB mortality. First, we used data from multiple sources to estimate COVID-19-disrupted BCG vaccination coverage. Second, using a static mathematical model, we estimated the number of additional paediatric TB deaths in the first 15 years of life due to delayed/missed vaccinations in 14 scenarios-varying in duration of disruption, and magnitude and timing of catch-up. We estimated a 25% reduction in global BCG coverage within the disruption period. The best-case scenario (3-month disruption, 100% catch-up within 3 months) resulted in an additional 886 (0.5%) paediatric TB deaths, and the worst-case scenario (6-month disruption with no catch-up) resulted in an additional 33,074 (17%) deaths. The magnitude of catch-up was found to be the most influential variable in minimising excess paediatric TB mortality. Our results show that ensuring catch-up vaccination of missed children is a critical priority, and delivery of BCG alongside other routine vaccines may be a feasible way to achieve catch-up. Urgent action is required to support countries with recovering vaccination coverages to minimise paediatric deaths.

20.
Nat Commun ; 12(1): 6278, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725363

RESUMO

During tumor progression, cancer cells come into contact with various non-tumor cell types, but it is unclear how tumors adapt to these new environments. Here, we integrate spatially resolved transcriptomics, single-cell RNA-seq, and single-nucleus RNA-seq to characterize tumor-microenvironment interactions at the tumor boundary. Using a zebrafish model of melanoma, we identify a distinct "interface" cell state where the tumor contacts neighboring tissues. This interface is composed of specialized tumor and microenvironment cells that upregulate a common set of cilia genes, and cilia proteins are enriched only where the tumor contacts the microenvironment. Cilia gene expression is regulated by ETS-family transcription factors, which normally act to suppress cilia genes outside of the interface. A cilia-enriched interface is conserved in human patient samples, suggesting it is a conserved feature of human melanoma. Our results demonstrate the power of spatially resolved transcriptomics in uncovering mechanisms that allow tumors to adapt to new environments.


Assuntos
Neoplasias/genética , Transcriptoma , Microambiente Tumoral , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo , RNA-Seq , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
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