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1.
Proc Natl Acad Sci U S A ; 121(31): e2404727121, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39052829

RESUMEN

Characterizing unknown viruses is essential for understanding viral ecology and preparing against viral outbreaks. Recovering complete genome sequences from environmental samples remains computationally challenging using metagenomics, especially for low-abundance species with uneven coverage. We present an experimental method for reliably recovering complete viral genomes from complex environmental samples. Individual genomes are encapsulated into droplets and amplified using multiple displacement amplification. A unique gene detection assay, which employs an RNA-based probe and an exonuclease, selectively identifies droplets containing the target viral genome. Labeled droplets are sorted using a microfluidic sorter, and genomes are extracted for sequencing. We demonstrate this method's efficacy by spiking two known viral genomes, Simian virus 40 (SV40, 5,243 bp) and Human Adenovirus 5 (HAd5, 35,938 bp), into a sewage sample with a final abundance in the droplets of around 0.1% and 0.015%, respectively. We achieve 100% recovery of the complete sequence of the spiked-in SV40 genome with uniform coverage distribution. For the larger HAd5 genome, we cover approximately 99.4% of its sequence. Notably, genome recovery is achieved with as few as one sorted droplet, which enables the recovery of any desired genomes in complex environmental samples, regardless of their abundance. This method enables single-genome whole-genome amplification and targeting characterizations of rare viral species and will facilitate our ability to access the mutational profile in single-virus genomes and contribute to an improved understanding of viral ecology.


Asunto(s)
Genoma Viral , Virus 40 de los Simios , Genoma Viral/genética , Virus 40 de los Simios/genética , Virus 40 de los Simios/aislamiento & purificación , Metagenómica/métodos , Humanos , Adenovirus Humanos/genética , Adenovirus Humanos/aislamiento & purificación , Aguas del Alcantarillado/virología
2.
Nature ; 629(8013): 919-926, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38589574

RESUMEN

RAS oncogenes (collectively NRAS, HRAS and especially KRAS) are among the most frequently mutated genes in cancer, with common driver mutations occurring at codons 12, 13 and 611. Small molecule inhibitors of the KRAS(G12C) oncoprotein have demonstrated clinical efficacy in patients with multiple cancer types and have led to regulatory approvals for the treatment of non-small cell lung cancer2,3. Nevertheless, KRASG12C mutations account for only around 15% of KRAS-mutated cancers4,5, and there are no approved KRAS inhibitors for the majority of patients with tumours containing other common KRAS mutations. Here we describe RMC-7977, a reversible, tri-complex RAS inhibitor with broad-spectrum activity for the active state of both mutant and wild-type KRAS, NRAS and HRAS variants (a RAS(ON) multi-selective inhibitor). Preclinically, RMC-7977 demonstrated potent activity against RAS-addicted tumours carrying various RAS genotypes, particularly against cancer models with KRAS codon 12 mutations (KRASG12X). Treatment with RMC-7977 led to tumour regression and was well tolerated in diverse RAS-addicted preclinical cancer models. Additionally, RMC-7977 inhibited the growth of KRASG12C cancer models that are resistant to KRAS(G12C) inhibitors owing to restoration of RAS pathway signalling. Thus, RAS(ON) multi-selective inhibitors can target multiple oncogenic and wild-type RAS isoforms and have the potential to treat a wide range of RAS-addicted cancers with high unmet clinical need. A related RAS(ON) multi-selective inhibitor, RMC-6236, is currently under clinical evaluation in patients with KRAS-mutant solid tumours (ClinicalTrials.gov identifier: NCT05379985).


Asunto(s)
Antineoplásicos , Mutación , Neoplasias , Proteína Oncogénica p21(ras) , Proteínas Proto-Oncogénicas p21(ras) , Animales , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Guanosina Trifosfato/metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Proteína Oncogénica p21(ras)/antagonistas & inhibidores , Proteína Oncogénica p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Adv Mater ; 36(31): e2309860, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38615189

RESUMEN

Artificial antigen-presenting cells (aAPCs) are currently used to manufacture T cells for adoptive therapy in cancer treatment, but a readily tunable and modular system can enable both rapid T cell expansion and control over T cell phenotype. Here, it is shown that microgels with tailored surface biochemical properties can serve as aAPCs to mediate T cell activation and expansion. Surface functionalization of microgels is achieved via layer-by-layer coating using oppositely charged polymers, forming a thin but dense polymer layer on the surface. This facile and versatile approach is compatible with a variety of coating polymers and allows efficient and flexible surface-specific conjugation of defined peptides or proteins. The authors demonstrate that tethering appropriate stimulatory ligands on the microgel surface efficiently activates T cells for polyclonal and antigen-specific expansion. The expansion, phenotype, and functional outcome of primary mouse and human T cells can be regulated by modulating the concentration, ratio, and distribution of stimulatory ligands presented on microgel surfaces as well as the stiffness and viscoelasticity of the microgels.


Asunto(s)
Células Presentadoras de Antígenos , Microgeles , Propiedades de Superficie , Linfocitos T , Animales , Células Presentadoras de Antígenos/inmunología , Linfocitos T/citología , Linfocitos T/metabolismo , Humanos , Microgeles/química , Ratones , Proliferación Celular/efectos de los fármacos , Activación de Linfocitos , Polímeros/química
4.
Science ; 384(6692): 209-213, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38603504

RESUMEN

Oil and water can only be mixed by dispersing droplets of one fluid in the other. When two droplets approach one another, the thin film that separates them invariably becomes unstable, causing the droplets to coalesce. The only known way to avoid this instability is through addition of a third component, typically a surfactant, which stabilizes the thin film at its equilibrium thickness. We report the observation that a thin fluid film of oil separating two water droplets can lead to an adhesive interaction between the droplets. Moreover, this interaction prevents their coalescence over timescales of several weeks, without the use of any surfactant or solvent.

5.
Int J Cancer ; 155(1): 7-18, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38533694

RESUMEN

Immune checkpoint inhibitors (ICIs) have been extensively used in immunological therapy primarily due to their ability to prolong patient survival. Although ICIs have achieved success in cancer treatment, the resistance of ICIs should not be overlooked. Ferroptosis is a newly found cell death mode characterized by the accumulation of reactive oxygen species (ROS), glutathione (GSH) depletion, and glutathione peroxidase 4 (GPX4) inactivation, which has been demonstrated to be beneficial to immunotherapy and combining ferroptosis and ICIs to exploit new immunotherapies may reverse ICIs resistance. Exosomes act as mediators in cell-to-cell communication that may regulate ferroptosis to influence immunotherapy through the secretion of biological molecules. Thus, utilizing exosomes to target ferroptosis has opened up exciting possibilities for reversing ICIs resistance. In this review, we summarize the mechanisms of ferroptosis improving ICIs therapy and how exosomes regulate ferroptosis through adjusting iron metabolism, blocking the ROS accumulation, controlling ferroptosis defense systems, and influencing classic signaling pathways and how engineered exosomes target ferroptosis and improve ICIs efficiency.


Asunto(s)
Resistencia a Antineoplásicos , Exosomas , Ferroptosis , Inhibidores de Puntos de Control Inmunológico , Neoplasias , Animales , Humanos , Exosomas/metabolismo , Ferroptosis/efectos de los fármacos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Inmunoterapia/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/metabolismo , Especies Reactivas de Oxígeno/metabolismo
6.
Immunology ; 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38517066

RESUMEN

Colorectal cancer (CRC) is a frequent gastrointestinal malignancy with high rates of morbidity and mortality; 85% of these tumours are proficient mismatch repair (pMMR)-microsatellite instability-low (MSI-L)/microsatellite stable (MSS) CRC known as 'cold' tumours that are resistant to immunosuppressive drugs. Monotherapy with programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors is ineffective for treating MSS CRC, making immunotherapy for MSS CRC a bottleneck. Recent studies have found that the multi-pathway regimens combined with PD-1/PD-L1 inhibitors can enhance the efficacy of anti-PD-1/PD-L1 in MSS CRC by increasing the number of CD8+ T cells, upregulating PD-L1 expression and improving the tumour microenvironment. This paper reviews the research progress of PD-1/PD-L1 inhibitors in combination with cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors, oncolytic virus, intestinal flora, antiangiogenic agents, chemotherapy, radiotherapy and epigenetic drugs for the treatment of pMMR-MSI-L/MSS CRC.

7.
Aquac Nutr ; 2024: 3893671, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38464590

RESUMEN

The present study investigated the effects of Astragalus membranaceus extract (AME) on growth performance, immune response, and energy metabolism of juvenile largemouth bass (Micropterus salmoides). Seven diets containing 0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, and 0.6% AME (Con, AME0.1, AME0.2, AME0.3, AME0.4, AME0.5, and AME0.6 groups) were formulated and fed to M. salmoides for 8 weeks. Final body weight (FBW), feed intake (FI), weight gain (WG), and specific growth rate (SGR) were all significantly higher in AME0.4 group than in Con group (P < 0.05). Feed conversion rate (FCR) was significantly improved in AME0.5 group compared with Con group (P < 0.05). Whole-body crude protein contents were significantly increased in AME0.2 group (P < 0.05). Whole-body crude lipid contents were significantly lower in AME0.2 and AME0.3 groups, while muscle lipid was upregulated by dietary AME (P < 0.05). Hepatic malondialdehyde (MDA) contents were significantly lowered in AME0.3 and AME0.4 groups, and catalase (CAT) activities were significantly increased in AME0.1 and AME0.2 groups (P < 0.05). Plasma aspartate aminotransferase (AST) level was significantly lowered in AME0.5, and AME0.6 groups, and alanine aminotransferase (ALT) level was lowered in AME0.5 groups (P < 0.05). Plasma triglyceride was declined in AME0.6 group, and glucose was decreased by 0.3%-0.5% AME (P < 0.05). Significantly higher hepatocyte diameter, lamina propria width, and submucosal layer thickness were recorded in AME0.6 groups, while the longest villi height was obtained in AME0.2 and AME0.3 groups (P < 0.05). The mRNA expression levels of insulin-like growth factor 1 (igf1) revealed the growth-promoting effect of AME. The anti-inflammatory and antiapoptotic effects of AME were demonstrated by transcription levels of interleukin 8 (il-8), tumor necrosis factor-alpha (tnf-a), caspase, B-cell lymphoma-xl (Bcl-xl), bcl-2 associated x (Bax), and bcl-2-associated death protein (Bad). The transcription levels of lipid metabolism and gluconeogenesis related genes, including acetyl-CoA carboxylase alpha (acc1), fatty acid synthase (fasn), fatty acid binding protein 1 (fabp1), phosphoenolpyruvate carboxykinase 2 (pepck2), and glucose-6-phosphatase catalytic subunit 1a (g6pc), were reduced by AME treatment, while the levels of glycolysis-related genes, including glucokinase (gck) and pyruvate kinase (pk), were the highest in AME0.2 and AME0.3 groups (P < 0.05). According to polynomial regression analysis of SGR, WG, FCR, whole-body crude lipid, MDA, and ALT, the optimal AME supplementation level was estimated to be 0.320%-0.429% of the diet. These results provided insights into the roles of AME in regulating immunity and metabolism, which highly indicated its potential as immunostimulants and metabolic regulators in diverse aquatic animals.

8.
Technol Cancer Res Treat ; 23: 15330338231198972, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38200714

RESUMEN

Background: To investigate the expression of high mobility group box B-1 (HMGB-1) in patients with colorectal cancer (CRC) and its association with clinicopathological features and prognosis in colorectal carcinoma by combining bioinformatics and clinical data analysis, and to clarify the role of HMGB-1. To examine whether HMGB-1 expression is related to the damage of the intestinal mucosal barrier, and then explore the potential HMGB-1-dependent mechanisms affecting the progression of CRC. Methods: CRC datasets of GSE12945, GSE17536, and GSE17537 from the public gene chip database were screened and downloaded. Clinical information and CRC tissue samples from patients with stage I-III CRC from the hospital were collected. Serum samples of patients were applied by enzyme-linked immunosorbent assay on HMGB-1, and were divided into high and low HMGB-1 expression, which was examined by 16S rDNA sequencing. Immunohistochemistry was performed to examine the relationship between the expression of HMGB-1 and tight junction protein, occludin, tumor necrosis factor-α, and interferon-γ. Results: Based on the Cutoff value of 10.24 ng/mL, the CRC patients were divided into high and low expression groups. In the HMGB-1H patient group, the TNM staging, overall survival, disease-free survival, recurrence, and metastasis were inferior to the HMGB-1L group. The results of 16S rDNA sequencing demonstrated that the Providencia genus was found to be enriched in the HMGB-1L group. Immunohistochemical results showed that HMGB-1 expression was negatively correlated with the expression of ZO-1 and occludin (R = 0.035, R = 0.003, P < .05), but was positively correlated with the expression of TNF-α and IFN-γ (R = 0.016, R = 0.001, P < .05). Conclusion: The survival of CRC patients with positive HMGB-1 expression was significantly shortened, which may be related to the decrease of Rovitensis content, the decreased expression of ZO-1 and occludin, and the increased levels of TNF-α and IFN-γ, which in turn damage the intestinal mucosal barrier, leading to the development of CRC.


Asunto(s)
Neoplasias Colorrectales , Factor de Necrosis Tumoral alfa , Humanos , Neoplasias Colorrectales/genética , ADN Ribosómico , Ocludina , Pronóstico
9.
Cancer Res ; 84(5): 771-784, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38190716

RESUMEN

Colorectal cancer development and outcome are impacted by modifiable risk factors, including psychologic stress. The gut microbiota has also been shown to be linked to psychologic factors. Here, we found a marked deteriorative effect of chronic stress in multiple colorectal cancer models, including chemically induced (AOM/DSS), genetically engineered (APCmin/+), and xenograft tumor mouse models. RNA sequencing data from colon tissues revealed that expression of stemness-related genes was upregulated in the stressed colorectal cancer group by activated ß-catenin signaling, which was further confirmed by results from ex vivo organoid analyses as well as in vitro and in vivo cell tumorigenicity assays. 16S rRNA sequencing of the gut microbiota showed that chronic stress disrupted gut microbes, and antibiotic treatment and fecal microbiota transplantation abolished the stimulatory effects of chronic stress on colorectal cancer progression. Stressed colorectal cancer mice displayed a significant decrease in Lactobacillus johnsonii (L. johnsonii) abundance, which was inversely correlated with tumor load. Moreover, protocatechuic acid (PCA) was identified as a beneficial metabolite produced by L. johnsonii based on metabolome sequencing and LC/MS-MS analysis. Replenishment of L. johnsonii or PCA blocked chronic stress-induced colorectal cancer progression by decreasing ß-catenin expression. Furthermore, PCA activated the cGMP pathway, and the cGMP agonist sildenafil abolished the effects of chronic stress on colorectal cancer. Altogether, these data identify that stress impacts the gut microbiome to support colorectal cancer progression. SIGNIFICANCE: Chronic stress stimulates cancer stemness by reducing the intestinal abundance of L. johnsonii and its metabolite PCA to enhance ß-catenin signaling, forming a basis for potential strategies to circumvent stress-induced cancer aggressiveness. See related commentary by McCollum and Shah, p. 645.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Lactobacillus johnsonii , Humanos , Animales , Ratones , Neoplasias Colorrectales/metabolismo , beta Catenina/genética , Lactobacillus johnsonii/genética , ARN Ribosómico 16S/genética
10.
Cancer Lett ; 582: 216567, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38070822

RESUMEN

EphB1 is implicated in numerous physiological and pathological processes, including nervous system diseases, cardiovascular diseases and cancers. It binds to membrane-bound ligands and drives bidirectional signaling. EphB1, along with its ligand ehrinB, plays a pivotal role in activating immune cells. However, despite its presence in dendritic cells (DCs), EphB1's involvement in the differentiation and maturation of DCs in cancers remains inadequately understood. In this study, we found compromised differentiation and maturation of DCs in EphB1-/- mice bearing lung adenocarcinoma syngeneic tumors. Our in vitro assays revealed that EphB1 phosphorylation induced DC differentiation and maturation. Cox-2, a key enzyme involved in the production of proinflammatory molecules, is implicated in DC differentiation induced by phosphorylated EphB1. Additionally, the study has identified lead compounds that specifically target EphB1 phosphorylation sites. Collectively, this research on EphB1 phosphorylation has provided valuable insights into the regulation of immune cell functionality and holds the potential for the development of innovative therapeutic strategies for a range of diseases.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Ratones , Animales , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Transducción de Señal , Diferenciación Celular , Células Dendríticas
11.
Biochim Biophys Acta Rev Cancer ; 1879(2): 189057, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38158025

RESUMEN

Several clinical trials and experimental studies have recently shown that vitamin K (VK) supplementation benefits the human body. Specifically, VK participates in coagulation and is associated with cellular senescence and cancer. VK has a potential anticancer effect in various cancers, such as pancreatic and prostate cancers. Through anti-inflammatory and antioxidant effects, VK can prevent senescence and inhibit cancer metastasis. Therefore, cancer prognosis can be improved by preventing cellular senescence. In addition, VK can inhibit the proliferation, growth, and differentiation of cancer cells through various mechanisms, including induction of c-myc and c-fos genes, regulation of B-cell lymphoma-2 (Bcl-2) and p21 genes, and angiogenesis inhibition. This review aims to discuss the relationship among VK, cellular senescence, and cancer metastasis and thus may improve comprehension of the specific functions of VK in human health. The potential application of VK as an adjuvant therapy for cancer (or in combination with traditional chemotherapy drugs or other vitamins) has also been highlighted.


Asunto(s)
Neoplasias , Vitamina K , Masculino , Humanos , Vitamina K/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/genética
12.
BMC Health Serv Res ; 23(1): 1250, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37964274

RESUMEN

BACKGROUND: Efforts to reduce emergency department (ED) volumes often target frequent users. We examined transitions in care across ED, hospital, and community settings, and in-hospital death, for high system users (HSUs) compared to controls. METHODS: Population-based databases provided ED visits and hospitalizations in Alberta and Ontario, Canada. The retrospective cohort included the top 10% of all the ED users during 2015/2016 (termed HSUs) and a random sample of controls (4 per each HSU) from the bottom 90% per province. Rates of transitions among ED, hospitalization, community settings, and in-hospital mortality were adjusted for sociodemographic and ED variables in a multistate statistical model. RESULTS: There were 2,684,924 patients and 579,230 (21.6%) were HSUs. Patient characteristics associated with shorter community to ED transition times for HSUs included Alberta residence (ratio of hazard ratio [RHR] = 1.11, 95% confidence interval [CI] 1.11,1.12), living in areas in the lower income quintile (RHR = 1.06, 95%CI 1.06,1.06), and Ontario residents without a primary health care provider (RHR = 1.13, 95%CI 1.13,1.14). Once at the ED, characteristics associated with shorter ED to hospital transition times for HSUs included higher acuity (e.g., RHR = 1.70, 95% CI 1.61, 1.81 for emergent), and for many diagnoses including chest pain (RHR = 1.71, 95%CI 1.65,1.76) and gastrointestinal (RHR = 1.66, 95%CI 1.62,1.71). Once admitted to hospital, HSUs did not necessarily have longer stays except for conditions such as chest pain (RHR = 0.90, 95% CI 0.86, 0.95). HSUs had shorter times to death in the ED if they presented for cancer (RHR = 2.51), congestive heart failure (RHR = 1.93), myocardial infarction (RHR = 1.53), and stroke (RHR = 1.84), and shorter times to death in-hospital if they presented with cancer (RHR = 1.29). CONCLUSIONS: Differences between HSUs and controls in predictors of transitions among care settings were identified. Co-morbidities and limitations in access to primary care are associated with more rapid transitions from community to ED and hospital among HSUs. Interventions targeting these challenges may better serve patients across health systems.. TRIAL REGISTRATION: Not applicable.


Asunto(s)
Servicio de Urgencia en Hospital , Neoplasias , Humanos , Estudios Retrospectivos , Mortalidad Hospitalaria , Dolor en el Pecho/epidemiología , Dolor en el Pecho/terapia , Atención a la Salud , Ontario/epidemiología
13.
Nat Prod Res ; : 1-6, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38006329

RESUMEN

Ent-kaurane diterpenoids were studied as a biologically active ingredient group of Sigesbeckia pubescens (Makino) Makino. Here, five known ent-kaurane diterpenoids were isolated and identified, named ent-16ß,17-dihydroxy-kauran-19-oic acid (1), ent-16ß,17-dihydroxy-kauran-19-oate (2), ent-18-acetoxy-17-hydroxykauran-19-oic acid (3), ent-16ß,17,18-trihydroxy-kauran-19 -oic acid (4), and ent-17-hydroxy-kauran-16ßH-19-oic acid (5). Their inhibitory effects of these compounds on MDA-MB-231 breast cancer migration were firstly tested in a chemotaxis invasion assay. Among them, compound 1 (DKA) showed superior inhibitory activities with IC50 value of 1.96 µM. Then, a wound healing assay and BALB/c nude mice were used for further studying the inhibitory activity of DKA on MDA-MB-231 breast cancer migration in vitro and in vivo, respectively. The wound healing assay showed that DKA (1, 5, and 25 µM) can significantly inhibit cell migration and the mouse model of lung metastasis showed that DKA (2.5, 5, and 10 mg/kg) could strongly suppress the lung metastasis of MDA-MB-231 breast cancer cells.

14.
bioRxiv ; 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38014300

RESUMEN

Characterizing unknown viruses is essential for understanding viral ecology and preparing against viral outbreaks. Recovering complete genome sequences from environmental samples remains computationally challenging using metagenomics, especially for low-abundance species with uneven coverage. This work presents a method for reliably recovering complete viral genomes from complex environmental samples. Individual genomes are encapsulated into droplets and amplified using multiple displacement amplification. A novel gene detection assay, which employs an RNA-based probe and an exonuclease, selectively identifies droplets containing the target viral genome. Labeled droplets are sorted using a microfluidic sorter, and genomes are extracted for sequencing. Validation experiments using a sewage sample spiked with two known viruses demonstrate the method's efficacy. We achieve 100% recovery of the spiked-in SV40 (Simian virus 40, 5243bp) genome sequence with uniform coverage distribution, and approximately 99.4% for the larger HAd5 genome (Human Adenovirus 5, 35938bp). Notably, genome recovery is achieved with as few as one sorted droplet, which enables the recovery of any desired genomes in complex environmental samples, regardless of their abundance. This method enables targeted characterizations of rare viral species and whole-genome amplification of single genomes for accessing the mutational profile in single virus genomes, contributing to an improved understanding of viral ecology.

15.
Proc Natl Acad Sci U S A ; 120(33): e2301366120, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37549257

RESUMEN

A wide range of macromolecules can undergo phase separation, forming biomolecular condensates in living cells. These membraneless organelles are typically highly dynamic, formed reversibly, and carry out essential functions in biological systems. Crucially, however, a further liquid-to-solid transition of the condensates can lead to irreversible pathological aggregation and cellular dysfunction associated with the onset and development of neurodegenerative diseases. Despite the importance of this liquid-to-solid transition of proteins, the mechanism by which it is initiated in normally functional condensates is unknown. Here we show, by measuring the changes in structure, dynamics, and mechanics in time and space, that single-component FUS condensates do not uniformly convert to a solid gel, but rather that liquid and gel phases coexist simultaneously within the same condensate, resulting in highly inhomogeneous structures. Furthermore, our results show that this transition originates at the interface between the condensate and the dilute continuous phase, and once initiated, the gelation process propagates toward the center of the condensate. To probe such spatially inhomogeneous rheology during condensate aging, we use a combination of established micropipette aspiration experiments together with two optical techniques, spatial dynamic mapping and reflective confocal dynamic speckle microscopy. These results reveal the importance of the spatiotemporal dimension of the liquid-to-solid transition and highlight the interface of biomolecular condensates as a critical element in driving pathological protein aggregation.


Asunto(s)
Condensados Biomoleculares , Agregación Patológica de Proteínas , Humanos , Microscopía Confocal , Reología , Proteína FUS de Unión a ARN
16.
Science ; 381(6659): 794-799, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37590355

RESUMEN

The discovery of small-molecule inhibitors requires suitable binding pockets on protein surfaces. Proteins that lack this feature are considered undruggable and require innovative strategies for therapeutic targeting. KRAS is the most frequently activated oncogene in cancer, and the active state of mutant KRAS is such a recalcitrant target. We designed a natural product-inspired small molecule that remodels the surface of cyclophilin A (CYPA) to create a neomorphic interface with high affinity and selectivity for the active state of KRASG12C (in which glycine-12 is mutated to cysteine). The resulting CYPA:drug:KRASG12C tricomplex inactivated oncogenic signaling and led to tumor regressions in multiple human cancer models. This inhibitory strategy can be used to target additional KRAS mutants and other undruggable cancer drivers. Tricomplex inhibitors that selectively target active KRASG12C or multiple RAS mutants are in clinical trials now (NCT05462717 and NCT05379985).


Asunto(s)
Productos Biológicos , Ciclofilina A , Inmunofilinas , Chaperonas Moleculares , Neoplasias , Proteínas Proto-Oncogénicas p21(ras) , Humanos , Productos Biológicos/química , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Cisteína/química , Cisteína/genética , Chaperonas Moleculares/química , Chaperonas Moleculares/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/química , Proteínas Proto-Oncogénicas p21(ras)/genética , Transducción de Señal , Ciclofilina A/química , Ciclofilina A/metabolismo , Inmunofilinas/química , Inmunofilinas/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/genética
17.
Carcinogenesis ; 44(8-9): 631-641, 2023 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-37586059

RESUMEN

An increasing number of studies have reported the role of gut microbes in colorectal cancer (CRC) development, as they can be influenced by dietary metabolism and mediate alterations in host epigenetics, ultimately affecting CRC. Intake of specific dietary components can affect gut microbial composition and function, and their metabolism regulates important epigenetic functions that may influence CRC risk. Gut microbes can regulate epigenetic modifications through nutrient metabolism, including histone modification, DNA methylation, and noncoding RNAs. Epigenetics, in turn, determines the gut microbial composition and thus influences the risk of developing CRC. This review discusses the complex crosstalk between metabolic reprogramming, gut microbiota, and epigenetics in CRC and highlights the potential applications of the gut microbiota as a biomarker for the prevention, diagnosis, and therapy of CRC.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiología , Epigénesis Genética , Metilación de ADN , Dieta , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo
18.
Br J Nutr ; 130(10): 1689-1703, 2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37039459

RESUMEN

Zn is an important trace element involved in various biochemical processes in aquatic species. An 8-week rearing trial was thus conducted to investigate the effects of Zn on juvenile largemouth bass (Micropterus salmoides) by feeding seven diets, respectively, supplemented with no Zn (Con), 60 and 120 mg/kg inorganic Zn (Sul60 and Sul120), and 30, 60, 90 and 120 mg/kg organic Zn (Bio30, Bio60, Bio90 and Bio120). Sul120 and Bio120 groups showed significantly higher weight gain and specific growth rate than Con group, with Bio60 group obtaining the lowest viscerosomatic index and hepatosomatic index. 60 or 90 mg/kg organic Zn significantly facilitated whole body Zn retention. Up-regulation of hepatic superoxide dismutase, glutathione peroxidase and catalase activities and decline of malondialdehyde contents indicated augmented antioxidant capacities by organic Zn. Zn treatment also lowered plasma aminotransferase levels while promoting acid phosphatase activity and hepatic transcription levels of alp1, acp1 and lyz-c than deprivation of Zn. The alterations in whole body and liver crude lipid and plasma TAG contents illustrated the regulatory effect of Zn on lipid metabolism, which could be possibly attributed to the changes in hepatic expressions of acc1, pparγ, atgl and cpt1. These findings demonstrated the capabilities of Zn in potentiating growth and morphological performance, antioxidant capacity, immunity as well as regulating lipid metabolism in M. salmoides. Organic Zn could perform comparable effects at same or lower supplementation levels than inorganic Zn, suggesting its higher efficiency. 60 mg/kg supplementation of organic Zn could effectively cover the requirements of M. salmoides.


Asunto(s)
Antioxidantes , Lubina , Animales , Antioxidantes/metabolismo , Metabolismo de los Lípidos , Zinc/farmacología , Zinc/metabolismo , Suplementos Dietéticos , Dieta/veterinaria , Inmunidad
19.
Eur J Pharmacol ; 949: 175718, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37054937

RESUMEN

Colorectal cancer (CRC) stands as the second leading cause of cancer-related deaths worldwide with limited available medicines. While drug repurposing comes as a promising strategy for cancer treatment, we discovered that propranolol (Prop), a non-selective ß1 and ß2 adrenergic receptor blocker, significantly inhibited the development of subcutaneous CT26 CRC and AOM/DSS-induced CRC models. The RNA-seq analysis highlighted the activated immune pathways after Prop treatment, with KEGG analysis enriched in T-cell differentiation. Routine analyses of blood revealed a decrease in neutrophil to lymphocyte ratio, a biomarker of systemic inflammation, and a prognostic indicator in the Prop-treated groups in both CRC models. Analysis of the tumor-infiltrating immune cells exhibited that Prop regressed the exhaustion of CD4+ and CD8+ T cells in the CT26-derived graft models, which was further corroborated in the AOM/DSS-induced models. Furthermore, bioinformatic analysis fitted well with the experimental data, showing that ß2 adrenergic receptor (ADRB2) was positively correlated with T-cell exhaustion signature in various tumors. The in vitro experiment showed no direct effect of Prop on CT26 cell viability, while T cells were activated with significantly-upregulated production of IFN-γ and Granzyme B. Consistently, Prop was unable to restrain CT26 tumor growth in nude mice. At last, the combination of Prop and the chemotherapeutic drug Irinotecan acted out the strongest inhibition in CT26 tumor progress. Collectively, we repurpose Prop as a promising and economical therapeutic drug for CRC treatment and highlight T-cell as its target.


Asunto(s)
Neoplasias Colorrectales , Propranolol , Animales , Ratones , Propranolol/farmacología , Propranolol/uso terapéutico , Irinotecán/farmacología , Irinotecán/uso terapéutico , Linfocitos T CD8-positivos , Ratones Desnudos , Antagonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/uso terapéutico , Neoplasias Colorrectales/patología , Línea Celular Tumoral
20.
BMC Microbiol ; 23(1): 81, 2023 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-36966280

RESUMEN

As the Human Microbiome Project (HMP) progresses, the relationship between microbes and human health has been receiving increasing attention. A growing number of reports support the correlation between cancer and microbes. However, most studies have focused on bacteria, rather than fungal communities. In this study, we studied the alteration in lung mycobiome in patients with non-small-cell lung cancer (NSCLC) using metagenomic sequencing and qPCR. The higher fungal diversity and more complex network were observed in the patients with NSCLC. In addition, Alternaria arborescens was found as the most relevant fungus to NSCLC, and the enrichment of it in cancerous tissue was also detected. This study proposes that the changes in fungal communities may be closely related to lung cancer, and provides insights into further exploration the relationship between lung cancer and fungi.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Micobioma , Humanos , Hongos/genética , Pulmón
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