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1.
Cell ; 172(4): 825-840.e18, 2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29336888

RESUMO

Therapeutic harnessing of adaptive immunity via checkpoint inhibition has transformed the treatment of many cancers. Despite unprecedented long-term responses, most patients do not respond to these therapies. Immunotherapy non-responders often harbor high levels of circulating myeloid-derived suppressor cells (MDSCs)-an immunosuppressive innate cell population. Through genetic and pharmacological approaches, we uncovered a pathway governing MDSC abundance in multiple cancer types. Therapeutic liver-X nuclear receptor (LXR) agonism reduced MDSC abundance in murine models and in patients treated in a first-in-human dose escalation phase 1 trial. MDSC depletion was associated with activation of cytotoxic T lymphocyte (CTL) responses in mice and patients. The LXR transcriptional target ApoE mediated these effects in mice, where LXR/ApoE activation therapy elicited robust anti-tumor responses and also enhanced T cell activation during various immune-based therapies. We implicate the LXR/ApoE axis in the regulation of innate immune suppression and as a target for enhancing the efficacy of cancer immunotherapy in patients.


Assuntos
Apolipoproteínas E/imunologia , Imunidade Inata , Receptores X do Fígado/imunologia , Células Supressoras Mieloides/imunologia , Neoplasias Experimentais/imunologia , Animais , Apolipoproteínas E/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Linhagem Celular Tumoral , Feminino , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Células Supressoras Mieloides/patologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Immunity ; 56(7): 1649-1663.e5, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37236188

RESUMO

Allogeneic hematopoietic stem cell transplantation (alloHSCT) from donors lacking C-C chemokine receptor 5 (CCR5Δ32/Δ32) can cure HIV, yet mechanisms remain speculative. To define how alloHSCT mediates HIV cure, we performed MHC-matched alloHSCT in SIV+, anti-retroviral therapy (ART)-suppressed Mauritian cynomolgus macaques (MCMs) and demonstrated that allogeneic immunity was the major driver of reservoir clearance, occurring first in peripheral blood, then peripheral lymph nodes, and finally in mesenteric lymph nodes draining the gastrointestinal tract. While allogeneic immunity could extirpate the latent viral reservoir and did so in two alloHSCT-recipient MCMs that remained aviremic >2.5 years after stopping ART, in other cases, it was insufficient without protection of engrafting cells afforded by CCR5-deficiency, as CCR5-tropic virus spread to donor CD4+ T cells despite full ART suppression. These data demonstrate the individual contributions of allogeneic immunity and CCR5 deficiency to HIV cure and support defining targets of alloimmunity for curative strategies independent of HSCT.


Assuntos
Infecções por HIV , Transplante de Células-Tronco Hematopoéticas , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Macaca fascicularis , Carga Viral
3.
Nature ; 633(8028): 207-215, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39112700

RESUMO

Tumour innervation is associated with worse patient outcomes in multiple cancers1,2, which suggests that it may regulate metastasis. Here we observed that highly metastatic mouse mammary tumours acquired more innervation than did less-metastatic tumours. This enhanced innervation was driven by expression of the axon-guidance molecule SLIT2 in tumour vasculature. Breast cancer cells induced spontaneous calcium activity in sensory neurons and elicited release of the neuropeptide substance P (SP). Using three-dimensional co-cultures and in vivo models, we found that neuronal SP promoted breast tumour growth, invasion and metastasis. Moreover, patient tumours with elevated SP exhibited enhanced lymph node metastatic spread. SP acted on tumoral tachykinin receptors (TACR1) to drive death of a small population of TACR1high cancer cells. Single-stranded RNAs (ssRNAs) released from dying cells acted on neighbouring tumoural Toll-like receptor 7 (TLR7) to non-canonically activate a prometastatic gene expression program. This SP- and ssRNA-induced Tlr7 gene expression signature was associated with reduced breast cancer survival outcomes. Therapeutic targeting of this neuro-cancer axis with the TACR1 antagonist aprepitant, an approved anti-nausea drug, suppressed breast cancer growth and metastasis in multiple models. Our findings reveal that tumour-induced hyperactivation of sensory neurons regulates multiple aspects of metastatic progression in breast cancer through a therapeutically targetable neuropeptide/extracellular ssRNA sensing axis.


Assuntos
Neoplasias da Mama , Metástase Neoplásica , RNA , Células Receptoras Sensoriais , Substância P , Receptor 7 Toll-Like , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metástase Linfática , Invasividade Neoplásica , Proteínas do Tecido Nervoso/metabolismo , RNA/metabolismo , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Substância P/metabolismo , Análise de Sobrevida , Receptor 7 Toll-Like/metabolismo , Receptores da Neurocinina-1/metabolismo
4.
Nature ; 633(8031): 823-827, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39322731

RESUMO

Primary production in the sunlit surface ocean is regulated by the supply of key nutrients, primarily nitrate, phosphate and iron (Fe), required by phytoplankton to fix carbon dioxide into biomass1-3. Below the surface ocean, remineralization of sinking organic matter rapidly regenerates nutrients, and microbial metabolism in the upper mesopelagic 'twilight zone' (200-500 m) is thought to be limited by the delivery of labile organic carbon4,5. However, few studies have examined the role of nutrients in shaping microbial production in the mesopelagic6-8. Here we report the distribution and uptake of siderophores, biomarkers for microbial Fe deficiency9 across a meridional section of the eastern Pacific Ocean. Siderophore concentrations are high not only in chronically Fe-limited surface waters but also in the twilight zone underlying the North and South Pacific subtropical gyres, two key ecosystems for the marine carbon cycle. Our findings suggest that bacterial Fe deficiency owing to low Fe availability is probably characteristic of the twilight zone in several large ocean basins, greatly expanding the region of the marine water column in which nutrients limit microbial metabolism, with potential implications for ocean carbon storage.


Assuntos
Bactérias , Ecossistema , Ferro , Água do Mar , Sideróforos , Bactérias/metabolismo , Carbono/metabolismo , Carbono/análise , Ciclo do Carbono , Ferro/análise , Ferro/metabolismo , Oceano Pacífico , Fitoplâncton/metabolismo , Água do Mar/química , Água do Mar/microbiologia , Sideróforos/metabolismo , Luz Solar , Nutrientes/análise , Nutrientes/metabolismo
5.
Nature ; 613(7944): 588-594, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599979

RESUMO

Bacterial abortive-infection systems limit the spread of foreign invaders by shutting down or killing infected cells before the invaders can replicate1,2. Several RNA-targeting CRISPR-Cas systems (that is, types III and VI) cause abortive-infection phenotypes by activating indiscriminate nucleases3-5. However, a CRISPR-mediated abortive mechanism that leverages indiscriminate DNase activity of an RNA-guided single-effector nuclease has yet to be observed. Here we report that RNA targeting by the type V single-effector nuclease Cas12a2 drives abortive infection through non-specific cleavage of double-stranded DNA (dsDNA). After recognizing an RNA target with an activating protospacer-flanking sequence, Cas12a2 efficiently degrades single-stranded RNA (ssRNA), single-stranded DNA (ssDNA) and dsDNA. Within cells, the activation of Cas12a2 induces an SOS DNA-damage response and impairs growth, preventing the dissemination of the invader. Finally, we harnessed the collateral activity of Cas12a2 for direct RNA detection, demonstrating that Cas12a2 can be repurposed as an RNA-guided RNA-targeting tool. These findings expand the known defensive abilities of CRISPR-Cas systems and create additional opportunities for CRISPR technologies.


Assuntos
Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , DNA , RNA , Proteínas Associadas a CRISPR/metabolismo , DNA/metabolismo , DNA de Cadeia Simples/metabolismo , RNA/metabolismo , Resposta SOS em Genética , Dano ao DNA , RNA Guia de Sistemas CRISPR-Cas , Edição de Genes
6.
Nature ; 611(7935): 346-351, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36130725

RESUMO

Clinical outcomes of severe acute respiratory syndrome 2 (SARS-CoV-2) infection are highly heterogeneous, ranging from asymptomatic infection to lethal coronavirus disease 2019 (COVID-19). The factors underlying this heterogeneity remain insufficiently understood. Genetic association studies have suggested that genetic variants contribute to the heterogeneity of COVID-19 outcomes, but the underlying potential causal mechanisms are insufficiently understood. Here we show that common variants of the apolipoprotein E (APOE) gene, homozygous in approximately 3% of the world's population1 and associated with Alzheimer's disease, atherosclerosis and anti-tumour immunity2-5, affect COVID-19 outcome in a mouse model that recapitulates increased susceptibility conferred by male sex and advanced age. Mice bearing the APOE2 or APOE4 variant exhibited rapid disease progression and poor survival outcomes relative to mice bearing the most prevalent APOE3 allele. APOE2 and APOE4 mice exhibited increased viral loads as well as suppressed adaptive immune responses early after infection. In vitro assays demonstrated increased infection in the presence of APOE2 and APOE4 relative to APOE3, indicating that differential outcomes are mediated by differential effects of APOE variants on both viral infection and antiviral immunity. Consistent with these in vivo findings in mice, our results also show that APOE genotype is associated with survival in patients infected with SARS-CoV-2 in the UK Biobank (candidate variant analysis, P = 2.6 × 10-7). Our findings suggest APOE genotype to partially explain the heterogeneity of COVID-19 outcomes and warrant prospective studies to assess APOE genotyping as a means of identifying patients at high risk for adverse outcomes.


Assuntos
Apolipoproteínas E , COVID-19 , Genética Humana , Camundongos Transgênicos , SARS-CoV-2 , Animais , Humanos , Masculino , Camundongos , Apolipoproteína E2/genética , Apolipoproteína E3/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , COVID-19/genética , COVID-19/mortalidade , COVID-19/virologia , Camundongos Transgênicos/genética , Camundongos Transgênicos/virologia , Estudos Prospectivos , SARS-CoV-2/patogenicidade , Modelos Animais de Doenças
7.
Trends Genet ; 40(9): 739-746, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38910033

RESUMO

The emergence of aerobic respiration created unprecedented bioenergetic advantages, while imposing the need to protect critical genetic information from reactive byproducts of oxidative metabolism (i.e., reactive oxygen species, ROS). The evolution of histone proteins fulfilled the need to shield DNA from these potentially damaging toxins, while providing the means to compact and structure massive eukaryotic genomes. To date, several metabolism-linked histone post-translational modifications (PTMs) have been shown to regulate chromatin structure and gene expression. However, whether and how PTMs enacted by metabolically produced ROS regulate adaptive chromatin remodeling remain relatively unexplored. Here, we review novel mechanistic insights into the interactions of ROS with histones and their consequences for the control of gene expression regulation, cellular plasticity, and behavior.


Assuntos
Regulação da Expressão Gênica , Histonas , Oxirredução , Processamento de Proteína Pós-Traducional , Espécies Reativas de Oxigênio , Histonas/metabolismo , Histonas/genética , Processamento de Proteína Pós-Traducional/genética , Regulação da Expressão Gênica/genética , Humanos , Espécies Reativas de Oxigênio/metabolismo , Animais , Montagem e Desmontagem da Cromatina/genética , Cromatina/genética , Cromatina/metabolismo
8.
Nature ; 586(7828): 299-304, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32999457

RESUMO

Blood vessels support tumours by providing nutrients and oxygen, while also acting as conduits for the dissemination of cancer1. Here we use mouse models of breast and lung cancer to investigate whether endothelial cells also have active 'instructive' roles in the dissemination of cancer. We purified genetically tagged endothelial ribosomes and their associated transcripts from highly and poorly metastatic tumours. Deep sequencing revealed that metastatic tumours induced expression of the axon-guidance gene Slit2 in endothelium, establishing differential expression between the endothelial (high Slit2 expression) and tumoural (low Slit2 expression) compartments. Endothelial-derived SLIT2 protein and its receptor ROBO1 promoted the migration of cancer cells towards endothelial cells and intravasation. Deleting endothelial Slit2 suppressed metastatic dissemination in mouse models of breast and lung cancer. Conversely, deletion of tumoural Slit2 enhanced metastatic progression. We identified double-stranded RNA derived from tumour cells as an upstream signal that induces expression of endothelial SLIT2 by acting on the RNA-sensing receptor TLR3. Accordingly, a set of endogenous retroviral element RNAs were upregulated in metastatic cells and detected extracellularly. Thus, cancer cells co-opt innate RNA sensing to induce a chemotactic signalling pathway in endothelium that drives intravasation and metastasis. These findings reveal that endothelial cells have a direct instructive role in driving metastatic dissemination, and demonstrate that a single gene (Slit2) can promote or suppress cancer progression depending on its cellular source.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Endotélio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Proteínas do Tecido Nervoso/metabolismo , Receptor 3 Toll-Like/metabolismo , Animais , Quimiotaxia , Modelos Animais de Doenças , Progressão da Doença , Células Endoteliais/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Camundongos , Metástase Neoplásica/genética , Proteínas do Tecido Nervoso/genética , RNA de Cadeia Dupla , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Transdução de Sinais , Receptor 3 Toll-Like/deficiência , Receptor 3 Toll-Like/genética , Células Tumorais Cultivadas , Proteínas Roundabout
9.
Mol Cell ; 69(1): 146-157.e3, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29304331

RESUMO

CRISPR-Cas systems offer versatile technologies for genome engineering, yet their implementation has been outpaced by ongoing discoveries of new Cas nucleases and anti-CRISPR proteins. Here, we present the use of E. coli cell-free transcription-translation (TXTL) systems to vastly improve the speed and scalability of CRISPR characterization and validation. TXTL can express active CRISPR machinery from added plasmids and linear DNA, and TXTL can output quantitative dynamics of DNA cleavage and gene repression-all without protein purification or live cells. We used TXTL to measure the dynamics of DNA cleavage and gene repression for single- and multi-effector CRISPR nucleases, predict gene repression strength in E. coli, determine the specificities of 24 diverse anti-CRISPR proteins, and develop a fast and scalable screen for protospacer-adjacent motifs that was successfully applied to five uncharacterized Cpf1 nucleases. These examples underscore how TXTL can facilitate the characterization and application of CRISPR technologies across their many uses.


Assuntos
Sistemas CRISPR-Cas/genética , Sistema Livre de Células/metabolismo , Escherichia coli/genética , Engenharia Genética/métodos , Biossíntese de Proteínas/genética , Transcrição Gênica/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , DNA Bacteriano/genética , Endonucleases/metabolismo , Oryza/genética , RNA Guia de Cinetoplastídeos/genética
10.
Proc Natl Acad Sci U S A ; 120(8): e2215792120, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36795752

RESUMO

HIV-1 strains are categorized into one of three neutralization tiers based on the relative ease by which they are neutralized by plasma from HIV-1-infected donors not on antiretroviral therapy; tier-1 strains are particularly sensitive to neutralization while tier-2 and tier-3 strains are increasingly difficult to neutralize. Most broadly neutralizing antibodies (bnAbs) previously described target the native prefusion conformation of HIV-1 Envelope (Env), but the relevance of the tiered categories for inhibitors targeting another Env conformation, the prehairpin intermediate, is not well understood. Here, we show that two inhibitors targeting distinct highly conserved regions of the prehairpin intermediate have strikingly consistent neutralization potencies (within ~100-fold for a given inhibitor) against strains in all three neutralization tiers of HIV-1; in contrast, best-in-class bnAbs targeting diverse Env epitopes vary by more than 10,000-fold in potency against these strains. Our results indicate that antisera-based HIV-1 neutralization tiers are not relevant for inhibitors targeting the prehairpin intermediate and highlight the potential for therapies and vaccine efforts targeting this conformation.


Assuntos
Anticorpos Amplamente Neutralizantes , Infecções por HIV , HIV-1 , Humanos , Anticorpos Neutralizantes , Produtos do Gene env do Vírus da Imunodeficiência Humana , Anticorpos Anti-HIV , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Testes de Neutralização
11.
Mol Biol Evol ; 41(9)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39288165

RESUMO

A few iconic examples have proven the value of facilitated gene flow for counteracting inbreeding depression and staving off extinction; yet, the practice is often not implemented for fear of causing outbreeding depression. Using genomic sequencing, climatic niche modeling, and demographic reconstruction, we sought to assess the risks and benefits of using translocations as a tool for recovery of endangered montane red fox (Vulpes vulpes) populations in the western United States. We demonstrated elevated inbreeding and homozygosity of deleterious alleles across all populations, but especially those isolated in the Cascade and Sierra Nevada ranges. Consequently, translocations would be expected to increase population growth by masking deleterious recessive alleles. Demographic reconstructions further indicated shallow divergences of less than a few thousand years among montane populations, suggesting low risk of outbreeding depression. These genomic-guided findings set the stage for future management, the documentation of which will provide a roadmap for recovery of other data-deficient taxa.


Assuntos
Raposas , Animais , Raposas/genética , Fluxo Gênico , Espécies em Perigo de Extinção , Endogamia , Genoma , Conservação dos Recursos Naturais
12.
Arterioscler Thromb Vasc Biol ; 44(5): 1144-1155, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38511326

RESUMO

BACKGROUND: Elevated apoB-containing lipoproteins (=remnants+LDLs [low-density lipoproteins]) are a major risk factor for atherosclerotic cardiovascular disease, including peripheral artery disease (PAD) and myocardial infarction. We tested the hypothesis that remnants and LDL both explain part of the increased risk of PAD conferred by elevated apoB-containing lipoproteins. For comparison, we also studied the risk of chronic limb-threatening ischemia and myocardial infarction. METHODS: apoB, remnant cholesterol, and LDL cholesterol were measured in 93 461 individuals without statin use at baseline from the Copenhagen General Population Study (2003-2015). During up to 15 years of follow-up, 1207 had PAD, 552 had chronic limb-threatening ischemia, and 2022 had myocardial infarction in the Danish National Patient Registry. Remnant and LDL cholesterol were calculated from a standard lipid profile. Remnant and LDL particle counts were additionally measured with nuclear magnetic resonance spectroscopy in 25 347 of the individuals. Results were replicated in 302 167 individuals without statin use from the UK Biobank (2004-2010). RESULTS: In the Copenhagen General Population Study, multivariable adjusted hazard ratios for risk of PAD per 1 mmol/L (39 mg/dL) increment in remnant and LDL cholesterol were 1.9 (95% CI, 1.5-2.4) and 1.1 (95% CI, 1.0-1.2), respectively; corresponding results in the UK Biobank were 1.7 (95% CI, 1.4-2.1) and 0.9 (95% CI, 0.9-1.0), respectively. In the association from elevated apoB to increased risk of PAD, remnant and LDL cholesterol explained 73% (32%-100%) and 8% (0%-46%), respectively; corresponding results were 63% (30%-100%) and 0% (0%-33%) for risk of chronic limb-threatening ischemia and 41% (27%-55%) and 54% (38%-70%) for risk of myocardial infarction; results for remnant and LDL particle counts corroborated these findings. CONCLUSIONS: PAD risk conferred by elevated apoB-containing lipoproteins was explained mainly by elevated remnants, while myocardial infarction risk was explained by both elevated remnants and LDL.


Assuntos
Apolipoproteína B-100 , Biomarcadores , LDL-Colesterol , Colesterol , Lipoproteínas , Doença Arterial Periférica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apolipoproteína B-100/sangue , Biomarcadores/sangue , Colesterol/sangue , LDL-Colesterol/sangue , Dinamarca/epidemiologia , Isquemia/sangue , Isquemia/epidemiologia , Isquemia/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Doença Arterial Periférica/epidemiologia , Doença Arterial Periférica/sangue , Doença Arterial Periférica/diagnóstico , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Triglicerídeos
13.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35064086

RESUMO

Sensory receptive fields combine features that originate in different neural pathways. Retinal ganglion cell receptive fields compute intensity changes across space and time using a peripheral region known as the surround, a property that improves information transmission about natural scenes. The visual features that construct this fundamental property have not been quantitatively assigned to specific interneurons. Here, we describe a generalizable approach using simultaneous intracellular and multielectrode recording to directly measure and manipulate the sensory feature conveyed by a neural pathway to a downstream neuron. By directly controlling the gain of individual interneurons in the circuit, we show that rather than transmitting different temporal features, inhibitory horizontal cells and linear amacrine cells synchronously create the linear surround at different spatial scales and that these two components fully account for the surround. By analyzing a large population of ganglion cells, we observe substantial diversity in the relative contribution of amacrine and horizontal cell visual features while still allowing individual cells to increase information transmission under the statistics of natural scenes. Established theories of efficient coding have shown that optimal information transmission under natural scenes allows a diverse set of receptive fields. Our results give a mechanism for this theory, showing how distinct neural pathways synthesize a sensory computation and how this architecture both generates computational diversity and achieves the objective of high information transmission.


Assuntos
Modelos Biológicos , Retina/fisiologia , Vias Visuais , Algoritmos , Células Amácrinas/metabolismo , Interneurônios/metabolismo , Células Ganglionares da Retina/metabolismo , Células Horizontais da Retina/metabolismo , Transmissão Sináptica
14.
J Am Chem Soc ; 146(19): 13427-13437, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712858

RESUMO

This study assesses the atmospheric impact of reactions between unsaturated hydrocarbons such as isoprene and monoterpenes and peroxy radicals containing various functional groups. We find that reactions between alkenes and acyl peroxy radicals have reaction rates high enough to be feasible in the atmosphere and lead to high molar mass accretion products. Moreover, the reaction between unsaturated hydrocarbons and acyl peroxy radicals leads to an alkyl radical, to which molecular oxygen rapidly adds. This finding is confirmed by both theoretical calculations and experiments. The formed perester peroxy radical may either undergo further H-shift reactions or react bimolecularly. The multifunctional oxygenated compounds formed through acyl peroxy radical + alkene reactions are potentially important contributors to particle formation and growth. Thus, acyl peroxy radical-initiated oxidation chemistry may need to be included in atmospheric models.

15.
Cancer ; 130(3): 453-466, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37803521

RESUMO

BACKGROUND: The 2018 Leibovich prognostic model for nonmetastatic renal cell carcinoma (RCC) combines clinical, surgical, and pathologic factors to predict progression-free survival (PFS) and cancer-specific survival (CSS) for patients with clear cell (ccRCC), papillary (pRCC), and chromophobe (chRCC) histology. Despite high accuracy, <1% of the original cohort was Black. Here, the authors examined this model in a large population with greater Black patient representation. METHODS: By using a prospectively maintained RCC institutional database, patients were assigned Leibovich model risk scores. Survival outcomes included 5-year and 10-year PFS and CSS. Prognostic accuracy was determined using area under the curve (AUC) analysis and calibration plots. Black patient subanalyses were conducted. RESULTS: In total, 657 (29%) of 2295 patients analyzed identified as Black. Declines in PFS and CSS were observed as scores increased. Discrimination for ccRCC was strong for PFS (AUC: 5-year PFS, 0.81; 10-year PFS, 0.78) and for CSS (AUC: 5-year CSS, 0.82; 10-year CSS, 0.74). The pRCC AUC for PFS was 0.74 at 5 years and 0.71 at 10 years; and the AUC for CSS was 0.74 at 5 years and 0.70 at 10 years. In chRCC, better performance was observed for CSS (AUC at 5 years, 0.75) than for PFS (AUC: 0.66 at 5 years; 0.55 at 10 years). Black patient subanalysis revealed similar-to-improved performance for ccRCC at 5 years (AUC: PFS, 0.79; CSS, 0.87). For pRCC, performance was lower for PFS (AUC at 5 years, 0.63) and was similar for CSS (AUC at 5 years, 0.77). Sample size limited Black patient 10-year and chRCC analyses. CONCLUSIONS: The authors externally validated the 2018 Leibovich RCC prognostic model and found optimal performance for ccRCC, followed by pRCC, and then chRCC. Importantly, the results were consistent in this large representation of Black patients. PLAIN LANGUAGE SUMMARY: In 2018, a model to predict survival in patients with renal cell carcinoma (kidney cancer) was introduced by Leibovich et al. This model has performed well; however, Black patients have been under-represented in examination of its performance. In this study, 657 Black patients (29%) were included, and the results were consistent. This work is important for making sure the model can be applied to all patient populations.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Prognóstico , Neoplasias Renais/patologia , Intervalo Livre de Progressão , Estudos Retrospectivos
16.
J Transl Med ; 22(1): 292, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504345

RESUMO

BACKGROUND: Naturally occurring colorectal cancers (CRC) in rhesus macaques share many features with their human counterparts and are useful models for cancer immunotherapy; but mechanistic data are lacking regarding the comparative molecular pathogenesis of these cancers. METHODS: We conducted state-of-the-art imaging including CT and PET, clinical assessments, and pathological review of 24 rhesus macaques with naturally occurring CRC. Additionally, we molecularly characterized these tumors utilizing immunohistochemistry (IHC), microsatellite instability assays, DNAseq, transcriptomics, and developed a DNA methylation-specific qPCR assay for MLH1, CACNA1G, CDKN2A, CRABP1, and NEUROG1, human markers for CpG island methylator phenotype (CIMP). We furthermore employed Monte-Carlo simulations to in-silico model alterations in DNA topology in transcription-factor binding site-rich promoter regions upon experimentally demonstrated DNA methylation. RESULTS: Similar cancer histology, progression patterns, and co-morbidities could be observed in rhesus as reported for human CRC patients. IHC identified loss of MLH1 and PMS2 in all cases, with functional microsatellite instability. DNA sequencing revealed the close genetic relatedness to human CRCs, including a similar mutational signature, chromosomal instability, and functionally-relevant mutations affecting KRAS (G12D), TP53 (R175H, R273*), APC, AMER1, ALK, and ARID1A. Interestingly, MLH1 mutations were rarely identified on a somatic or germline level. Transcriptomics not only corroborated the similarities of rhesus and human CRCs, but also demonstrated the significant downregulation of MLH1 but not MSH2, MSH6, or PMS2 in rhesus CRCs. Methylation-specific qPCR suggested CIMP-positivity in 9/16 rhesus CRCs, but all 16/16 exhibited significant MLH1 promoter hypermethylation. DNA hypermethylation was modelled to affect DNA topology, particularly propeller twist and roll profiles. Modelling the DNA topology of a transcription factor binding motif (TFAP2A) in the MLH1 promoter that overlapped with a methylation-specific probe, we observed significant differences in DNA topology upon experimentally shown DNA methylation. This suggests a role of transcription factor binding interference in epigenetic silencing of MLH1 in rhesus CRCs. CONCLUSIONS: These data indicate that epigenetic silencing suppresses MLH1 transcription, induces the loss of MLH1 protein, abrogates mismatch repair, and drives genomic instability in naturally occurring CRC in rhesus macaques. We consider this spontaneous, uninduced CRC in immunocompetent, treatment-naïve rhesus macaques to be a uniquely informative model for human CRC.


Assuntos
Neoplasias Encefálicas , Neoplasias Colorretais , Instabilidade de Microssatélites , Síndromes Neoplásicas Hereditárias , Humanos , Animais , Macaca mulatta/genética , Macaca mulatta/metabolismo , Proteína 1 Homóloga a MutL/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Epigênese Genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , DNA/metabolismo , Reparo de Erro de Pareamento de DNA/genética
17.
PLoS Pathog ; 18(3): e1010396, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35358290

RESUMO

The CCR5-specific antibody Leronlimab is being investigated as a novel immunotherapy that can suppress HIV replication with minimal side effects. Here we studied the virological and immunological consequences of Leronlimab in chronically CCR5-tropic HIV-1 infected humans (n = 5) on suppressive antiretroviral therapy (ART) and in ART-naïve acutely CCR5-tropic SHIV infected rhesus macaques (n = 4). All five human participants transitioned from daily combination ART to self-administered weekly subcutaneous (SC) injections of 350 mg or 700 mg Leronlimab and to date all participants have sustained virologic suppression for over seven years. In all participants, Leronlimab fully occupied CCR5 receptors on peripheral blood CD4+ T cells and monocytes. In ART-naïve rhesus macaques acutely infected with CCR5-tropic SHIV, weekly SC injections of 50 mg/kg Leronlimab fully suppressed plasma viremia in half of the macaques. CCR5 receptor occupancy by Leronlimab occurred concomitant with rebound of CD4+ CCR5+ T-cells in peripheral blood, and full CCR5 receptor occupancy was found in multiple anatomical compartments. Our results demonstrate that weekly, self-administered Leronlimab was safe, well-tolerated, and efficacious for long-term virologic suppression and should be included in the arsenal of safe, easily administered, longer-acting antiretroviral treatments for people living with HIV-1. Trial Registration: ClinicalTrials.gov Identifiers: NCT02175680 and NCT02355184.


Assuntos
Vírus da Imunodeficiência Símia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Anti-HIV , Humanos , Macaca mulatta , Receptores CCR5
18.
J Urol ; 212(4): 531-538, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38934789

RESUMO

PURPOSE: In 2023 the American Urological Association (AUA) requested an Update Literature Review (ULR) to incorporate new evidence generated since the 2019 publication of this Guideline. The resulting 2024 Guideline Amendment addresses updated recommendations to provide guidance for the care of patients with incontinence after prostate treatment (IPT). MATERIALS AND METHODS: In 2023, the IPT Guideline was updated through the AUA amendment process in which newly published literature is reviewed and integrated into previously published guidelines. There were 82 studies of interest initially identified in preliminary abstract review. Following full-text review, 17 studies met inclusion criteria and ultimately informed the statements of interest. RESULTS: The Panel developed evidence- and consensus-based statements based on an updated review to provide guidance for the care of patients who experience IPT. These updates are detailed herein. CONCLUSIONS: As prostate treatments are refined, a decreasing incidence of incontinence is anticipated. This Guideline will require further review as the diagnostic and treatment options for patients with IPT continue to evolve.


Assuntos
Incontinência Urinária , Humanos , Masculino , Incontinência Urinária/terapia , Incontinência Urinária/diagnóstico , Prostatectomia/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Complicações Pós-Operatórias/prevenção & controle , Urologia/normas , Estados Unidos
19.
J Urol ; 211(3): 354-363, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38079459

RESUMO

PURPOSE: We evaluate the efficacy and safety profiles of currently available conservative management options for penile and urethral lichen sclerosus. MATERIALS AND METHODS: A systematic review of existing literature on lichen sclerosus was conducted utilizing the PubMed, Embase, and Web of Science databases. References were assessed for relevance to nonsurgical management of male genital lichen sclerosus by title and abstract by 3 independent reviewers, then reviewed in full and in duplicate by 5 independent reviewers. RESULTS: Seventeen studies describing conservative management of histologically confirmed penile and urethral lichen sclerosus in male patients were included in the final review. We present available evidence supporting the use of 4 major treatment modalities represented in the existing literature: topical corticosteroids, tacrolimus, platelet-rich plasma, and CO2 laser. We also briefly discuss the limited studies on the use of oral acitretin and polydeoxyribonucleotide injections. Outcomes assessed include symptoms, clinical appearance, quality of life, sexual satisfaction, adverse effects, and long-term efficacy of treatment. CONCLUSIONS: Topical corticosteroids remain the mainstay of conservative management of penile and urethral lichen sclerosus, with current literature supporting the use of other therapies such as tacrolimus and platelet-rich plasma as alternatives or adjuvant treatments when escalation of treatment is necessary. Future research should further explore the efficacy and safety of newer therapies through additional controlled clinical trials in the targeted population.


Assuntos
Líquen Escleroso e Atrófico , Estreitamento Uretral , Humanos , Masculino , Líquen Escleroso e Atrófico/tratamento farmacológico , Tacrolimo/uso terapêutico , Tratamento Conservador , Qualidade de Vida , Estreitamento Uretral/cirurgia , Glucocorticoides
20.
J Urol ; : 101097JU0000000000004264, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39357026

RESUMO

PURPOSE: To compare Fournier's gangrene in female and male patients, and identify mortality-associated characteristics in both. MATERIALS AND METHODS: We employed National Inpatient Sample data (2016-2020) to identify Fournier's gangrene cases and extracted demographic, comorbidity, and procedural variables. Multivariable regression models were utilized to identify mortality risk factors for both cohorts. RESULTS: We identified 2875 females (31%) and 6451 males (69%) with Fournier's gangrene corresponding to an estimated 14,375 (95% CI 13,784-14,966) and 32,255 (95% CI 31,390-33,120) cases, respectively. Females were more likely to die than males (7.1% vs 5.7%, P < .0001, respectively). Median incidence rates were 1.7 (IQR 1.5-1.8) and 4 (IQR 3.6-4.3) cases per 100,000 person-years for females and males, respectively. Females had higher median age, longer hospital stays, more charges, procedures, and fecal diversion rates, but lower routine discharges than males (P < .05). Non-White females had increased mortality odds compared to White females (odds ratio [OR] 1.49, 95% CI 1.07-2.07, P = .019). Prolonged interval until initial perineal debridement correlated with higher mortality odds in both females and males (OR 1.02, 95% CI 1-1.04, P = .034 vs OR 1.03, 95% CI 1.01-1.05, P < .0001). Diabetes lowered mortality odds in females and males (OR 0.68, 95% CI 0.47-0.99, P = .046 vs OR 0.54, 95% CI 0.41-0.7, P < .0001). CONCLUSIONS: In females, Fournier's gangrene incidence surpasses previous reports, with slightly worse outcomes compared to males, emphasizing the need for precise clinical assessment and early intensive interventions.

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