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1.
Cell ; 181(6): 1329-1345.e24, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32445698

RESUMO

Posterior fossa A (PFA) ependymomas are lethal malignancies of the hindbrain in infants and toddlers. Lacking highly recurrent somatic mutations, PFA ependymomas are proposed to be epigenetically driven tumors for which model systems are lacking. Here we demonstrate that PFA ependymomas are maintained under hypoxia, associated with restricted availability of specific metabolites to diminish histone methylation, and increase histone demethylation and acetylation at histone 3 lysine 27 (H3K27). PFA ependymomas initiate from a cell lineage in the first trimester of human development that resides in restricted oxygen. Unlike other ependymomas, transient exposure of PFA cells to ambient oxygen induces irreversible cellular toxicity. PFA tumors exhibit a low basal level of H3K27me3, and, paradoxically, inhibition of H3K27 methylation specifically disrupts PFA tumor growth. Targeting metabolism and/or the epigenome presents a unique opportunity for rational therapy for infants with PFA ependymoma.


Assuntos
Ependimoma/genética , Ependimoma/metabolismo , Epigenoma/genética , Neoplasias Infratentoriais/genética , Neoplasias Infratentoriais/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular , Proliferação de Células/genética , Metilação de DNA/genética , Epigenômica/métodos , Histonas/genética , Histonas/metabolismo , Humanos , Lactente , Lisina/genética , Lisina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Mutação/genética
2.
Cell ; 158(2): 288-299, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25036629

RESUMO

The etiology of colorectal cancer (CRC) has been linked to deficiencies in mismatch repair and adenomatous polyposis coli (APC) proteins, diet, inflammatory processes, and gut microbiota. However, the mechanism through which the microbiota synergizes with these etiologic factors to promote CRC is not clear. We report that altering the microbiota composition reduces CRC in APC(Min/+)MSH2(-/-) mice, and that a diet reduced in carbohydrates phenocopies this effect. Gut microbes did not induce CRC in these mice through an inflammatory response or the production of DNA mutagens but rather by providing carbohydrate-derived metabolites such as butyrate that fuel hyperproliferation of MSH2(-/-) colon epithelial cells. Further, we provide evidence that the mismatch repair pathway has a role in regulating ß-catenin activity and modulating the differentiation of transit-amplifying cells in the colon. These data thereby provide an explanation for the interaction between microbiota, diet, and mismatch repair deficiency in CRC induction. PAPERCLIP:


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Carboidratos da Dieta/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Animais , Butiratos/metabolismo , Proliferação de Células , Transformação Celular Neoplásica , Pólipos do Colo/metabolismo , Pólipos do Colo/microbiologia , Pólipos do Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/microbiologia , Reparo de Erro de Pareamento de DNA , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Inflamação/genética , Inflamação/metabolismo , Inflamação/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/metabolismo , Organismos Livres de Patógenos Específicos , beta Catenina/metabolismo
3.
Nature ; 609(7929): 1021-1028, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36131014

RESUMO

Medulloblastoma (MB) comprises a group of heterogeneous paediatric embryonal neoplasms of the hindbrain with strong links to early development of the hindbrain1-4. Mutations that activate Sonic hedgehog signalling lead to Sonic hedgehog MB in the upper rhombic lip (RL) granule cell lineage5-8. By contrast, mutations that activate WNT signalling lead to WNT MB in the lower RL9,10. However, little is known about the more commonly occurring group 4 (G4) MB, which is thought to arise in the unipolar brush cell lineage3,4. Here we demonstrate that somatic mutations that cause G4 MB converge on the core binding factor alpha (CBFA) complex and mutually exclusive alterations that affect CBFA2T2, CBFA2T3, PRDM6, UTX and OTX2. CBFA2T2 is expressed early in the progenitor cells of the cerebellar RL subventricular zone in Homo sapiens, and G4 MB transcriptionally resembles these progenitors but are stalled in developmental time. Knockdown of OTX2 in model systems relieves this differentiation blockade, which allows MB cells to spontaneously proceed along normal developmental differentiation trajectories. The specific nature of the split human RL, which is destined to generate most of the neurons in the human brain, and its high level of susceptible EOMES+KI67+ unipolar brush cell progenitor cells probably predisposes our species to the development of G4 MB.


Assuntos
Diferenciação Celular , Neoplasias Cerebelares , Meduloblastoma , Metencéfalo , Diferenciação Celular/genética , Linhagem da Célula , Neoplasias Cerebelares/classificação , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Cerebelo/embriologia , Cerebelo/patologia , Subunidades alfa de Fatores de Ligação ao Core/genética , Proteínas Hedgehog/metabolismo , Histona Desmetilases , Humanos , Antígeno Ki-67/metabolismo , Meduloblastoma/classificação , Meduloblastoma/genética , Meduloblastoma/patologia , Metencéfalo/embriologia , Metencéfalo/patologia , Proteínas Musculares , Mutação , Fatores de Transcrição Otx/deficiência , Fatores de Transcrição Otx/genética , Proteínas Repressoras , Proteínas com Domínio T/metabolismo , Fatores de Transcrição
4.
Nature ; 589(7843): 597-602, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33361818

RESUMO

Isoprenoids are vital for all organisms, in which they maintain membrane stability and support core functions such as respiration1. IspH, an enzyme in the methyl erythritol phosphate pathway of isoprenoid synthesis, is essential for Gram-negative bacteria, mycobacteria and apicomplexans2,3. Its substrate, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), is not produced in metazoans, and in humans and other primates it activates cytotoxic Vγ9Vδ2 T cells at extremely low concentrations4-6. Here we describe a class of IspH inhibitors and refine their potency to nanomolar levels through structure-guided analogue design. After modification of these compounds into prodrugs for delivery into bacteria, we show that they kill clinical isolates of several multidrug-resistant bacteria-including those from the genera Acinetobacter, Pseudomonas, Klebsiella, Enterobacter, Vibrio, Shigella, Salmonella, Yersinia, Mycobacterium and Bacillus-yet are relatively non-toxic to mammalian cells. Proteomic analysis reveals that bacteria treated with these prodrugs resemble those after conditional IspH knockdown. Notably, these prodrugs also induce the expansion and activation of human Vγ9Vδ2 T cells in a humanized mouse model of bacterial infection. The prodrugs we describe here synergize the direct killing of bacteria with a simultaneous rapid immune response by cytotoxic γδ T cells, which may limit the increase of antibiotic-resistant bacterial populations.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Proteínas de Escherichia coli/antagonistas & inibidores , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/imunologia , Ativação Linfocitária/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Oxirredutases/antagonistas & inibidores , Linfócitos T Citotóxicos/efeitos dos fármacos , Animais , Resistência Microbiana a Medicamentos , Resistência a Múltiplos Medicamentos , Inibidores Enzimáticos/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Feminino , Meia-Vida , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Oxirredutases/deficiência , Oxirredutases/genética , Oxirredutases/metabolismo , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Especificidade por Substrato , Suínos/sangue , Linfócitos T Citotóxicos/imunologia
5.
Hum Mol Genet ; 33(11): 1015-1019, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38538568

RESUMO

The Northeastern region of India is considered a gateway for modern humans' dispersal throughout Asia. This region is a mixture of various ethnic and indigenous populations amalgamating multiple ancestries. One reason for such amalgamation is that, South Asia experienced multiple historic migrations from various parts of the world. A few examples explored genetically are Jews, Parsis and Siddis. Ahom is a dynasty that historically migrated to India during the 12th century. However, this putative migration has not been studied genetically at high resolution. Therefore, to validate this historical evidence, we genotyped autosomal data of the Modern Ahom population residing in seven sister states of India. Principal Component and Admixture analyses haave suggested a substantial admixture of the Ahom population with the local Tibeto-Burman populations. Moreover, the haplotype-based analysis has linked these Ahom individuals mainly with the Kusunda (a language isolated from Nepal) and Khasi (an Austroasiatic population of Meghalaya). Such unexpected presence of widespread population affinities suggests that Ahom mixed and assimilated a wide variety of Trans-Himalayan populations inhabiting this region after the migration. In summary, we observed a significant deviation of Ahom from their ancestral homeland (Thailand) and extensive admixture and assimilation with the local South Asian populations.


Assuntos
Etnicidade , Genética Populacional , Haplótipos , Migração Humana , Humanos , Índia/etnologia , Etnicidade/genética , Tailândia , Povo Asiático/genética , Migrantes
6.
EMBO Rep ; 24(5): e55373, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-36943011

RESUMO

Upon ex vivo culture, hematopoietic stem cells (HSCs) quickly lose potential and differentiate into progenitors. The identification of culture conditions that maintain the potential of HSCs ex vivo is therefore of high clinical interest. Here, we demonstrate that the potential of murine and human HSCs is maintained when cultivated for 2 days ex vivo at a pH of 6.9, in contrast to cultivation at the commonly used pH of 7.4. When cultivated at a pH of 6.9, HSCs remain smaller, less metabolically active, less proliferative and show enhanced reconstitution ability upon transplantation compared to HSC cultivated at pH 7.4. HSCs kept at pH 6.9 show an attenuated polyamine pathway. Pharmacological inhibition of the polyamine pathway in HSCs cultivated at pH 7.4 with DFMO mimics phenotypes and potential of HSCs cultivated at pH 6.9. Ex vivo exposure to a pH of 6.9 is therefore a positive regulator of HSC function by reducing polyamines. These findings might improve HSC short-term cultivation protocols for transplantation and gene therapy interventions.


Assuntos
Células-Tronco Hematopoéticas , Humanos , Camundongos , Animais , Células-Tronco Hematopoéticas/metabolismo , Concentração de Íons de Hidrogênio
7.
Nature ; 574(7780): 712-716, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31597163

RESUMO

Cancers are caused by genomic alterations known as drivers. Hundreds of drivers in coding genes are known but, to date, only a handful of noncoding drivers have been discovered-despite intensive searching1,2. Attention has recently shifted to the role of altered RNA splicing in cancer; driver mutations that lead to transcriptome-wide aberrant splicing have been identified in multiple types of cancer, although these mutations have only been found in protein-coding splicing factors such as splicing factor 3b subunit 1 (SF3B1)3-6. By contrast, cancer-related alterations in the noncoding component of the spliceosome-a series of small nuclear RNAs (snRNAs)-have barely been studied, owing to the combined challenges of characterizing noncoding cancer drivers and the repetitive nature of snRNA genes1,7,8. Here we report a highly recurrent A>C somatic mutation at the third base of U1 snRNA in several types of tumour. The primary function of U1 snRNA is to recognize the 5' splice site via base-pairing. This mutation changes the preferential A-U base-pairing between U1 snRNA and the 5' splice site to C-G base-pairing, and thus creates novel splice junctions and alters the splicing pattern of multiple genes-including known drivers of cancer. Clinically, the A>C mutation is associated with heavy alcohol use in patients with hepatocellular carcinoma, and with the aggressive subtype of chronic lymphocytic leukaemia with unmutated immunoglobulin heavy-chain variable regions. The mutation in U1 snRNA also independently confers an adverse prognosis to patients with chronic lymphocytic leukaemia. Our study demonstrates a noncoding driver in spliceosomal RNAs, reveals a mechanism of aberrant splicing in cancer and may represent a new target for treatment. Our findings also suggest that driver discovery should be extended to a wider range of genomic regions.


Assuntos
Mutação , Neoplasias/genética , RNA Nuclear Pequeno/genética , Spliceossomos/genética , Humanos , Neoplasias/patologia , Neoplasias/fisiopatologia , Sítios de Splice de RNA , Splicing de RNA , Fatores de Processamento de RNA/genética
8.
Nature ; 572(7767): 67-73, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31043743

RESUMO

Study of the origin and development of cerebellar tumours has been hampered by the complexity and heterogeneity of cerebellar cells that change over the course of development. Here we use single-cell transcriptomics to study more than 60,000 cells from the developing mouse cerebellum and show that different molecular subgroups of childhood cerebellar tumours mirror the transcription of cells from distinct, temporally restricted cerebellar lineages. The Sonic Hedgehog medulloblastoma subgroup transcriptionally mirrors the granule cell hierarchy as expected, while group 3 medulloblastoma resembles Nestin+ stem cells, group 4 medulloblastoma resembles unipolar brush cells, and PFA/PFB ependymoma and cerebellar pilocytic astrocytoma resemble the prenatal gliogenic progenitor cells. Furthermore, single-cell transcriptomics of human childhood cerebellar tumours demonstrates that many bulk tumours contain a mixed population of cells with divergent differentiation. Our data highlight cerebellar tumours as a disorder of early brain development and provide a proximate explanation for the peak incidence of cerebellar tumours in early childhood.


Assuntos
Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Evolução Molecular , Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Transcrição Gênica , Animais , Neoplasias Cerebelares/classificação , Cerebelo/citologia , Cerebelo/embriologia , Cerebelo/metabolismo , Criança , Feminino , Feto/citologia , Glioma/classificação , Glioma/genética , Glioma/patologia , Humanos , Meduloblastoma/classificação , Meduloblastoma/genética , Meduloblastoma/patologia , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Fatores de Tempo , Transcriptoma/genética
9.
Nature ; 574(7780): 707-711, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31664194

RESUMO

In cancer, recurrent somatic single-nucleotide variants-which are rare in most paediatric cancers-are confined largely to protein-coding genes1-3. Here we report highly recurrent hotspot mutations (r.3A>G) of U1 spliceosomal small nuclear RNAs (snRNAs) in about 50% of Sonic hedgehog (SHH) medulloblastomas. These mutations were not present across other subgroups of medulloblastoma, and we identified these hotspot mutations in U1 snRNA in only <0.1% of 2,442 cancers, across 36 other tumour types. The mutations occur in 97% of adults (subtype SHHδ) and 25% of adolescents (subtype SHHα) with SHH medulloblastoma, but are largely absent from SHH medulloblastoma in infants. The U1 snRNA mutations occur in the 5' splice-site binding region, and snRNA-mutant tumours have significantly disrupted RNA splicing and an excess of 5' cryptic splicing events. Alternative splicing mediated by mutant U1 snRNA inactivates tumour-suppressor genes (PTCH1) and activates oncogenes (GLI2 and CCND2), and represents a target for therapy. These U1 snRNA mutations provide an example of highly recurrent and tissue-specific mutations of a non-protein-coding gene in cancer.


Assuntos
Neoplasias Cerebelares/genética , Proteínas Hedgehog/genética , Meduloblastoma/genética , RNA Nuclear Pequeno/genética , Adolescente , Adulto , Processamento Alternativo , Proteínas Hedgehog/metabolismo , Humanos , Mutação , Sítios de Splice de RNA , Splicing de RNA
10.
Proc Natl Acad Sci U S A ; 119(22): e2117675119, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35613056

RESUMO

Fibrin is the fibrous protein network that comprises blood clots; it is uniquely capable of bearing very large tensile strains (up to 200%) due to multiscale force accommodation mechanisms. Fibrin is also a biochemical scaffold for numerous enzymes and blood factors. The biomechanics and biochemistry of fibrin have been independently studied. However, comparatively little is known about how fibrin biomechanics and biochemistry are coupled: how does fibrin deformation influence its biochemistry? In this study, we show that mechanically induced protein structural changes in fibrin affect fibrin biochemistry. We find that tensile deformation of fibrin leads to molecular structural transitions of α-helices to ß-sheets, which reduced binding of tissue plasminogen activator (tPA), an enzyme that initiates fibrin lysis. Moreover, binding of tPA and Thioflavin T, a commonly used ß-sheet marker, were mutually exclusive, further demonstrating the mechano-chemical control of fibrin biochemistry. Finally, we demonstrate that structural changes in fibrin suppressed the biological activity of platelets on mechanically strained fibrin due to reduced αIIbß3 integrin binding. Our work shows that mechanical strain regulates fibrin molecular structure and biological activity in an elegant mechano-chemical feedback loop, which possibly extends to other fibrous biopolymers.


Assuntos
Fibrina , Estresse Mecânico , Resistência à Tração , Benzotiazóis/química , Fibrina/química , Humanos , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Ativador de Plasminogênio Tecidual/química
11.
Eur Heart J ; 45(3): 181-194, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-37634192

RESUMO

BACKGROUND AND AIMS: Coronary flow capacity (CFC) is associated with an observed 10-year survival probability for individual patients before and after actual revascularization for comparison to virtual hypothetical ideal complete revascularization. METHODS: Stress myocardial perfusion (mL/min/g) and coronary flow reserve (CFR) per pixel were quantified in 6979 coronary artery disease (CAD) subjects using Rb-82 positron emission tomography (PET) for CFC maps of artery-specific size-severity abnormalities expressed as percent left ventricle with prospective follow-up to define survival probability per-decade as fraction of 1.0. RESULTS: Severely reduced CFC in 6979 subjects predicted low survival probability that improved by 42% after revascularization compared with no revascularization for comparable severity (P = .0015). For 283 pre-and-post-procedure PET pairs, severely reduced regional CFC-associated survival probability improved heterogeneously after revascularization (P < .001), more so after bypass surgery than percutaneous coronary interventions (P < .001) but normalized in only 5.7%; non-severe baseline CFC or survival probability did not improve compared with severe CFC (P = .00001). Observed CFC-associated survival probability after actual revascularization was lower than virtual ideal hypothetical complete post-revascularization survival probability due to residual CAD or failed revascularization (P < .001) unrelated to gender or microvascular dysfunction. Severely reduced CFC in 2552 post-revascularization subjects associated with low survival probability also improved after repeat revascularization compared with no repeat procedures (P = .025). CONCLUSIONS: Severely reduced CFC and associated observed survival probability improved after first and repeat revascularization compared with no revascularization for comparable CFC severity. Non-severe CFC showed no benefit. Discordance between observed actual and virtual hypothetical post-revascularization survival probability revealed residual CAD or failed revascularization.


Assuntos
Doença da Artéria Coronariana , Humanos , Radioisótopos de Rubídio , Estudos Prospectivos , Tomografia por Emissão de Pósitrons/métodos , Angiografia Coronária/métodos
12.
J Gen Virol ; 105(2)2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38376490

RESUMO

Reactive oxygen species (ROS) accumulation inside the cells instigates oxidative stress, activating stress-responsive genes. The viral strategies for promoting stressful conditions and utilizing the induced host proteins to enhance their replication remain elusive. The present work investigates the impact of oxidative stress responses on Newcastle disease virus (NDV) pathogenesis. Here, we show that the progression of NDV infection varies with intracellular ROS levels. Additionally, the results demonstrate that NDV infection modulates the expression of oxidative stress-responsive genes, majorly sirtuin 7 (SIRT7), a NAD+-dependent deacetylase. The modulation of SIRT7 protein, both through overexpression and knockdown, significantly impacts the replication dynamics of NDV in DF-1 cells. The activation of SIRT7 is found to be associated with the positive regulation of cellular protein deacetylation. Lastly, the results suggested that NDV-driven SIRT7 alters NAD+ metabolism in vitro and in ovo. We concluded that the elevated expression of NDV-mediated SIRT7 protein with enhanced activity metabolizes the NAD+ to deacetylase the host proteins, thus contributing to high virus replication.


Assuntos
Vírus da Doença de Newcastle , Sirtuínas , Animais , NAD , Vírus da Doença de Newcastle/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio , Sirtuínas/genética , Galinhas , Linhagem Celular
13.
Mol Genet Genomics ; 299(1): 8, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374307

RESUMO

Lakshadweep is an archipelago of 36 islands located in the Southeastern Arabian Sea. In the absence of a detailed archaeological record, the human settlement timing of this island is vague. Previous genetic studies on haploid DNA makers suggested sex-biased ancestry linked to North and South Indian populations. Maternal ancestry suggested a closer link with the Southern Indian, while paternal ancestry advocated the Northern Indian genetic affinity. Since the haploid markers are more sensitive to genetic drift, which is evident for the Island populations, we have used the biparental high-resolution single-nucleotide polymorphic markers to reconstruct the population history of Lakshadweep Islands.  Using the fine-scaled analyses, we specifically focused on (A) the ancestry components of Lakshadweep Islands populations; (B) their relation with East, West Eurasia and South Asia; (C) the number of founding lineages and (D) the putative migration from Northern India as the paternal ancestry was closer to the North Indian populations. Our analysis of ancestry components confirmed relatively higher North Indian ancestry among the Lakshadweep population. These populations are closely related to the South Asian populations. We identified mainly a single founding population for these Islands, geographically divided into two sub-clusters. By examining the population's genetic composition and analysing the gene flow from different source populations, this study contributes to our understanding of Lakshadweep Island's evolutionary history and population dynamics. These findings shed light on the complex interactions between ethnic groups and their genetic contributions in making the Lakshadweep population.


Assuntos
Etnicidade , Genética Populacional , Humanos , Etnicidade/genética , Povo Asiático/genética , Índia , Evolução Biológica
14.
Cancer Cell Int ; 24(1): 199, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840117

RESUMO

The extracellular matrix (ECM) is a dynamic and complex microenvironment that modulates cell behavior and cell fate. Changes in ECM composition and architecture have been correlated with development, differentiation, and disease progression in various pathologies, including breast cancer [1]. Studies have shown that aligned fibers drive a pro-metastatic microenvironment, promoting the transformation of mammary epithelial cells into invasive ductal carcinoma via the epithelial-to-mesenchymal transition (EMT) [2]. The impact of ECM orientation on breast cancer metabolism, however, is largely unknown. Here, we employ two non-invasive imaging techniques, fluorescence-lifetime imaging microscopy (FLIM) and intensity-based multiphoton microscopy, to assess the metabolic states of cancer cells cultured on ECM-mimicking nanofibers in a random and aligned orientation. By tracking the changes in the intrinsic fluorescence of nicotinamide adenine dinucleotide and flavin adenine dinucleotide, as well as expression levels of metastatic markers, we reveal how ECM fiber orientation alters cancer metabolism and EMT progression. Our study indicates that aligned cellular microenvironments play a key role in promoting metastatic phenotypes of breast cancer as evidenced by a more glycolytic metabolic signature on nanofiber scaffolds of aligned orientation compared to scaffolds of random orientation. This finding is particularly relevant for subsets of breast cancer marked by high levels of collagen remodeling (e.g. pregnancy associated breast cancer), and may serve as a platform for predicting clinical outcomes within these subsets [3-6].

15.
Crit Rev Biotechnol ; 44(2): 218-235, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36592989

RESUMO

The pretreatment and the enzymatic saccharification are the key steps in the extraction of fermentable sugars for further valorization of lignocellulosic biomass (LCB) to biofuels and value-added products via biochemical and/or chemical conversion routes. Due to low density and high-water absorption capacity of LCB, the large volume of water is required for its processing. Integration of pretreatment, saccharification, and co-fermentation has succeeded and well-reported in the literature. However, there are only few reports on extraction of fermentable sugars from LCB with high biomass loading (>10% Total solids-TS) feasible to industrial reality. Furthermore, the development of enzymatic cocktails can overcome technology hurdles with high biomass loading. Hence, a better understanding of constraints involved in the development of technology with high biomass loading can result in an economical and efficient yield of fermentable sugars for the production of biofuels and bio-chemicals with viable titer, rate, and yield (TRY) at industrial scale. The present review aims to provide a critical assessment on the production of fermentable sugars from lignocelluloses with high solid biomass loading. The impact of inhibitors produced during both pretreatment and saccharification has been elucidated. Moreover, the limitations imposed by high solid loading on efficient mass transfer during saccharification process have been elaborated.


Assuntos
Biocombustíveis , Lignina , Lignina/metabolismo , Açúcares , Tecnologia , Biomassa , Água , Hidrólise
16.
Chemistry ; : e202402145, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869100

RESUMO

Boron subphthalocyanines with chloride and fluoride axial ligands and three antimony complexes chelated by corroles that differ in size and electron-richness were examined as electrocatalysts for reduction of protons to hydrogen. Experiment- and computation-based investigations revealed that all redox events are ligand-centered and that the meso-C of the corroles and the peripheral N atoms of the subphthalocyanines are the largely preferred proton-binding sites.

17.
J Surg Oncol ; 129(7): 1224-1234, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38436618

RESUMO

BACKGROUND AND OBJECTIVES: The role of cell-free DNA (cfDNA) in operable nonsmall cell lung cancer (NSCLC) is unclear. This study was aimed to evaluate the feasibility for identification of cfDNA in pleural lavage fluid and its correlation with plasma in resectable NSCLCs. METHODS: Consecutively resected NSCLCs were evaluated for cfDNA levels in preoperative plasma (PLS1), intraoperative pleural-lavage (PLV) and postoperative (at 1 month) plasma sample (PLS2). CfDNA was isolated and measured quantitatively by qPCR in a TaqMan probe-detection approach using the human ß-actin gene as the amplifying target. RESULTS: All (n = 34) except one were negative for malignant cells in PLV cytology. CfDNA could be isolated from all the three samples (PLS1, PLV, and PLS2) successfully in each patient. The median cfDNA levels in PLS1, PLV and PLS2 were 118 ng/mL (IQR 61-158), 167 ng/mL (IQR 59.9-179.9) and 103 ng/mL (IQR 66.5-125.4) respectively. The median follow-up was 34.1 months (IQR 25.2-41.6). A significant overall-survival (OS) and disease-free survival (DFS) were recorded for patients with cfDNA level cut-offs at 125, 170, and 100 ng/mL, respectively for PLS1, PLV, and PLS2. Patients with raised cfDNA in PLS1 (>125 ng/mL) and PLV (>170 ng/mL) had significantly poorer 2-year OS, p = 0.005 and p = 0.012, respectively. The hazards (OS) were also higher for those with raised cfDNA in PLV (HR = 5.779, 95% CI = 1.162-28.745, p = 0.032). PLV (>170 ng/mL) had increased pleural recurrences (p = 0.021) and correlated significantly with poorer DFS at 2-years (p = 0.001) with increased hazards (HR = 9.767, 95% CI = 2.098-45.451, p = 0.004). Multivariable analysis suggested higher cfDNA in PLV as a poor prognostic factor for both OS and DFS. CONCLUSIONS: Among patients with operable NSCLC, it is feasible to identify cfDNA in pleural lavage and correlate PLV cfDNA with pleural recurrences and outcomes.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas , Ácidos Nucleicos Livres , Neoplasias Pulmonares , Irrigação Terapêutica , Humanos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Feminino , Projetos Piloto , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/sangue , Prognóstico , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , Irrigação Terapêutica/métodos , Estadiamento de Neoplasias , Seguimentos , Taxa de Sobrevida
18.
Virus Genes ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739246

RESUMO

The Newcastle disease virus (NDV) affects wild and domesticated bird species, including commercial poultry. Although the diversity of NDV in domestic chickens is well documented, limited information is available about Newcastle disease (ND) outbreaks in other bird species. We report an annotated sequence of NDV/Vulture/Borjuri/01/22, an avirulent strain of NDV reported from Borjuri, Northeast India, in Himalayan Griffon vulture. The complete genome is 15,186 bases long with a fusion protein (F) cleavage site 112GRQGR↓L117. The phylogenetic analysis based on the F protein gene and the whole genome sequence revealed that the isolate from the vulture belongs to genotype II, sharing significant homology with vaccine strain LaSota. The study highlights the possible spillover of the virus from domestic to wild species through the food chain.

19.
Ann Diagn Pathol ; 71: 152303, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636337

RESUMO

Philadelphia (Ph) chromosome (9;22)(q34;q11) comprises 90-95 % of chronic myeloid leukemia (CML), while 5-10 % of CML have translocations involving three or more chromosomes. The outcome of treating patients harbouring complex Ph-positive cytogenetics with tyrosine kinase inhibitors (TKI) is unclear. In the present systematic review, we aim to summarise the response of patients with complex Ph-positive cytogenetics to treatment with TKI therapy. We collated all available literature from databases such as PubMed, Google Scholar, Web of Science database, Cochrane library, Scopus and Embase (up until January 31st, 2024), which describe cases of patients with CML, harbouring complex Ph-positive variations (three and four-way translocations), and summarised their response to TKI therapy. The studies were screened for the following criteria: documented TKI intervention and outcome (whether CR was achieved). Studies that did not report the same, were excluded. Additionally, we report a case from our center of a 55-year-old patient with CML, positive for the Ph-chromosome, harbouring a three-way translocation involving chromosome 15 i.e. 46XX, t(9;15;22) (q34;p11;q11). Identification of BCR::ABL and involvement of chromosome 15 was carried out using conventional cytogenetics, fluorescence in situ hybridization (FISH), and quantitative PCR (qPCR). Based on the inclusion criteria, a total of 15 studies were included from which a total of 87 cases were covered. Overall, we identified 38 unique complex three- and four-way translocations across 87 Ph-positive cases and found that 85 patients with complex Ph-positive cytogenetics achieved complete remission upon treatment and did not appear to have a lesser response to TKI therapy.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Inibidores de Proteínas Quinases , Translocação Genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Pessoa de Meia-Idade , Cromossomo Filadélfia , Resultado do Tratamento , Masculino , Feminino
20.
Pediatr Surg Int ; 40(1): 57, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353772

RESUMO

PURPOSE: Wilms' tumor (WT) is a rare kidney cancer that primarily affects children. Exosomes are extracellular vesicles that cargo nucleic acids, proteins,etc. for cellular communication. Long non-coding RNAs (lncRNAs) have utility as biomarkers for cancer diagnosis, prognosis, and disease monitoring. We hypothesize that expression of lncRNA, metastasis-associated lung adenocarcinoma transcript-1(MALAT1), is dysregulated and possibly trafficked within exosomes to influence the tissue microenvironment for metastasis and recurrence of WT. METHODS: We investigated the expression of MALAT1 in thirty WT samples by qPCR. Exosomes were isolated using a precipitated and affinity-binding-based kit, and characterized using TEM, NTA, and DLS. RESULTS: Mean number of exosomes was 9.01×108/mL in primary culture, 1.64×108/mL in urine, and 4.65×108/plasma:400µl. Average yield of total RNA was 1.28µg (primary-culture supernatant:1ml), 1.47µg (Urine:1ml), 1.65µg (Plasma:400 µL). We quantified MALAT1 in exosomes derived from these sources in patients of WT. Expression of MALAT1 was significantly downregulated (p=0.008) in WT samples. CONCLUSION: This is the first study that demonstrated the presence of lncRNA MALAT1 in various invasive and non-invasive samples of patients with WT(primary tissue culture, urine, and plasma samples).


Assuntos
Exossomos , Neoplasias Renais , RNA Longo não Codificante , Tumor de Wilms , Criança , Humanos , RNA Longo não Codificante/genética , Tumor de Wilms/genética , Neoplasias Renais/genética , Biópsia Líquida , Exossomos/genética , Microambiente Tumoral
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