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2.
Sci Adv ; 10(5): eadk8970, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38295172

RESUMO

Micro/nanorobots provide a promising approach for intravascular therapy with high precision. However, blood vessel is a highly complex system, and performing interventional therapy in those submillimeter segments remains challenging. While micro/nanorobots can enter submillimeter segments, they may still comprise nonbiodegradable parts, posing a considerable challenge for post-use removal. Here, we developed a retrievable magnetic colloidal microswarm, composed of tPA-anchored Fe3O4@mSiO2 nanorobots (tPA-nbots), to archive tPA-mediated thrombolysis under balloon catheter-assisted magnetic actuation with x-ray fluoroscopy imaging system (CMAFIS). By deploying tPA-nbot transcatheter to the vicinity of the thrombus, the tPA-nbot microswarms were magnetically actuated to the blood clot at the submillimeter vessels with high precision. After thrombolysis, the tPA-nbots can be retrieved via the CMAFIS, as demonstrated in ex vivo organ of human placenta and in vivo carotid artery of rabbit. The proposed colloidal microswarm provides a promising robotic tool with high spatial precision for enhanced thrombolysis with low side effects.


Assuntos
Artérias , Ativador de Plasminogênio Tecidual , Animais , Humanos , Coelhos , Ativador de Plasminogênio Tecidual/uso terapêutico
3.
Cell ; 187(4): 882-896.e17, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38295787

RESUMO

Streptococcus anginosus (S. anginosus) was enriched in the gastric mucosa of patients with gastric cancer (GC). Here, we show that S. anginosus colonized the mouse stomach and induced acute gastritis. S. anginosus infection spontaneously induced progressive chronic gastritis, parietal cell atrophy, mucinous metaplasia, and dysplasia in conventional mice, and the findings were confirmed in germ-free mice. In addition, S. anginosus accelerated GC progression in carcinogen-induced gastric tumorigenesis and YTN16 GC cell allografts. Consistently, S. anginosus disrupted gastric barrier function, promoted cell proliferation, and inhibited apoptosis. Mechanistically, we identified an S. anginosus surface protein, TMPC, that interacts with Annexin A2 (ANXA2) receptor on gastric epithelial cells. Interaction of TMPC with ANXA2 mediated attachment and colonization of S. anginosus and induced mitogen-activated protein kinase (MAPK) activation. ANXA2 knockout abrogated the induction of MAPK by S. anginosus. Thus, this study reveals S. anginosus as a pathogen that promotes gastric tumorigenesis via direct interactions with gastric epithelial cells in the TMPC-ANXA2-MAPK axis.


Assuntos
Gastrite , Neoplasias Gástricas , Infecções Estreptocócicas , Streptococcus anginosus , Animais , Humanos , Camundongos , Atrofia/patologia , Carcinogênese , Transformação Celular Neoplásica , Mucosa Gástrica , Gastrite/patologia , Inflamação/patologia , Proteínas Quinases Ativadas por Mitógeno , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia , Streptococcus anginosus/fisiologia , Infecções Estreptocócicas/patologia
4.
Sci Adv ; 9(50): eadj0883, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100592

RESUMO

The magnetic microrobots promise benefits in minimally invasive cell-based therapy. However, they generally suffer from an inevitable compromise between their magnetic responsiveness and biomedical functions. Herein, we report a modularized microrobot consisting of magnetic actuation (MA) and cell scaffold (CS) modules. The MA module with strong magnetism and pH-responsive deformability and the CS module with cell loading-release capabilities were fabricated by three-dimensional printing technique. Subsequently, assembly of modules was performed by designing a shaft-hole structure and customizing their relative dimensions, which enabled magnetic navigation in complex environments, while not deteriorating the cellular functionalities. On-demand disassembly at targeted lesion was then realized to facilitate CS module delivery and retrieval of the MA module. Furthermore, the feasibility of proposed system was validated in an in vivo rabbit bile duct. Therefore, this work presents a modular design-based strategy that enables uncompromised fabrication of multifunctional microrobots and stimulates their development for future cell-based therapy.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Sistemas de Liberação de Medicamentos , Animais , Coelhos , Sistemas de Liberação de Medicamentos/métodos , Impressão Tridimensional
5.
Comput Struct Biotechnol J ; 21: 4804-4815, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37841330

RESUMO

The human microbiome is an emerging research frontier due to its profound impacts on health. High-throughput microbiome sequencing enables studying microbial communities but suffers from analytical challenges. In particular, the lack of dedicated preprocessing methods to improve data quality impedes effective minimization of biases prior to downstream analysis. This review aims to address this gap by providing a comprehensive overview of preprocessing techniques relevant to microbiome research. We outline a typical workflow for microbiome data analysis. Preprocessing methods discussed include quality filtering, batch effect correction, imputation of missing values, normalization, and data transformation. We highlight strengths and limitations of each technique to serve as a practical guide for researchers and identify areas needing further methodological development. Establishing robust, standardized preprocessing will be essential for drawing valid biological conclusions from microbiome studies.

6.
iScience ; 26(10): 107626, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37731616

RESUMO

Massive expansion of immature and suppressive myeloid cells is a common feature of malignant solid tumors. Over-expression of cyclin-dependent kinase 20, also known as cell cycle-related kinase (CCRK), in hepatocellular carcinoma (HCC) correlates with reduced patient survival and low immunotherapy responsiveness. Beyond tumor-intrinsic oncogenicity, here we demonstrated that CCRK is upregulated in myeloid cells in tumor-bearing mice and in patients with HCC. Intratumoral injection of Ccrk-knockdown myeloid-derived suppressor cells (MDSCs) increased tumor-infiltrating CD8+T cells and suppressed HCC tumorigenicity. Using an indel mutant transgenic model, we showed that Ccrk inactivation in myeloid cells conferred a mature phenotype with elevated IL-12 production, driving Th1 responses and CD8+T cell cytotoxicity to reduce orthotopic tumor growth and prolong survival. Mechanistically, CCRK activates STAT3/E4BP4 signaling in MDSCs to acquire immunosuppressive activity through transcriptional IL-10 induction and IL-12 suppression. Taken together, our findings unravel mechanistic insights into MDSC-mediated immunosuppression and offer a therapeutic kinase-target for cancer immunotherapy.

7.
Curr Diab Rep ; 23(10): 253-263, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37535293

RESUMO

PURPOSE OF REVIEW: Numerous observations have indicated an increased risk of developing various types of cancers, as well as cancer-related mortality, among patients with diabetes and obesity. The purpose of this review is to outline multiple-cancer screening among these patients through a team-based approach and to present the findings of a pioneering integrated care program designed for patients with obesity with a specific emphasis on cancer prevention. RECENT FINDINGS: A community-based multi-cancer prevention program, which provides all services in one location and utilizes team-based approaches, is reported to be feasible and has the potential to enhance the uptake rate of multiple cancers screening among patients with diabetes and obesity. The team-based approach is a commonly utilized method for managing patients with diabetes, obesity, and cancer, and has been shown to be efficacious. Nevertheless, research on team-based cancer screening programs for patients with diabetes and obesity remains limited. Providing a comprehensive screening for colorectal, prostate, and breast cancer, as well as metabolic syndrome, during a single clinic visit has been proven effective and well-received by participants.


Assuntos
Diabetes Mellitus , Síndrome Metabólica , Neoplasias , Masculino , Humanos , Neoplasias/complicações , Neoplasias/epidemiologia , Diabetes Mellitus/epidemiologia , Obesidade/complicações , Obesidade/epidemiologia
8.
Gastroenterology ; 165(2): 445-462, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37169182

RESUMO

BACKGROUND & AIMS: Immune checkpoint blockade therapy benefits only a small subset of patients with colorectal cancer (CRC), and identification of CRC-intrinsic events modulating immune checkpoint blockade efficacy is an unmet need. We found that AlkB homolog 5 (ALKBH5), an RNA N6-methyladenosine eraser, drives immunosuppression and is a molecular target to boost immune checkpoint blockade therapy in CRC. METHODS: Clinical significance of ALKBH5 was evaluated in human samples (n = 205). Function of ALKBH5 was investigated in allografts, CD34+ humanized mice, and Alkbh5 knockin mice. Immunity change was determined by means of flow cytometry, immunofluorescence, and functional investigation. Methylated RNA immunoprecipitation sequencing and RNA sequencing were used to identify ALKBH5 targets. Vesicle-like nanoparticle-encapsulated ALKBH5-small interfering RNA was constructed for targeting ALKBH5 in vivo. RESULTS: High ALKBH5 expression predicts poor prognosis in CRC. ALKBH5 induced myeloid-derived suppressor cell accumulation but reduced natural killer cells and cytotoxic CD8+ T cells to induce colorectal tumorigenesis in allografts, CD34+ humanized mice, and intestine-specific Alkbh5 knockin mice. Mechanistically, AXIN2, a Wnt suppressor, was identified as a target of ALKBH5. ALKBH5 binds and demethylates AXIN2 messenger RNA, which caused its dissociation from N6-methyladenosine reader IGF2BP1 and degradation, resulting in hyperactivated Wnt/ß-catenin. Subsequently, Wnt/ß-catenin targets, including Dickkopf-related protein 1 (DKK1) were induced by ALKBH5. ALKBH5-induced DKK1 recruited myeloid-derived suppressor cells to drive immunosuppression in CRC, and this effect was abolished by anti-DKK1 in vitro and in vivo. Finally, vesicle-like nanoparticle-encapsulated ALKBH5-small interfering RNA, or anti-DKK1 potentiated anti-PD1 treatment in suppressing CRC growth by enhancing antitumor immunity. CONCLUSIONS: This study identified an ALKBH5-N6-methyladenosine-AXIN2-Wnt-DKK1 axis in CRC, which drives immune suppression to facilitate tumorigenesis. Targeting of ALKBH5 is a promising strategy for sensitizing CRC to immunotherapy.


Assuntos
Neoplasias Colorretais , beta Catenina , Humanos , Camundongos , Animais , beta Catenina/genética , beta Catenina/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Inibidores de Checkpoint Imunológico/uso terapêutico , Carcinogênese/genética , Transformação Celular Neoplásica , RNA Interferente Pequeno/metabolismo , Imunoterapia , Terapia de Imunossupressão , Neoplasias Colorretais/terapia , Neoplasias Colorretais/tratamento farmacológico , Proteína Axina , Homólogo AlkB 5 da RNA Desmetilase/genética , Homólogo AlkB 5 da RNA Desmetilase/metabolismo
9.
Gut ; 72(9): 1758-1773, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37019619

RESUMO

OBJECTIVE: Therapy-induced tumour microenvironment (TME) remodelling poses a major hurdle for cancer cure. As the majority of patients with hepatocellular carcinoma (HCC) exhibits primary or acquired resistance to antiprogrammed cell death (ligand)-1 (anti-PD-[L]1) therapies, we aimed to investigate the mechanisms underlying tumour adaptation to immune-checkpoint targeting. DESIGN: Two immunotherapy-resistant HCC models were generated by serial orthotopic implantation of HCC cells through anti-PD-L1-treated syngeneic, immunocompetent mice and interrogated by single-cell RNA sequencing (scRNA-seq), genomic and immune profiling. Key signalling pathway was investigated by lentiviral-mediated knockdown and pharmacological inhibition, and further verified by scRNA-seq analysis of HCC tumour biopsies from a phase II trial of pembrolizumab (NCT03419481). RESULTS: Anti-PD-L1-resistant tumours grew >10-fold larger than parental tumours in immunocompetent but not immunocompromised mice without overt genetic changes, which were accompanied by intratumoral accumulation of myeloid-derived suppressor cells (MDSC), cytotoxic to exhausted CD8+ T cell conversion and exclusion. Mechanistically, tumour cell-intrinsic upregulation of peroxisome proliferator-activated receptor-gamma (PPARγ) transcriptionally activated vascular endothelial growth factor-A (VEGF-A) production to drive MDSC expansion and CD8+ T cell dysfunction. A selective PPARγ antagonist triggered an immune suppressive-to-stimulatory TME conversion and resensitised tumours to anti-PD-L1 therapy in orthotopic and spontaneous HCC models. Importantly, 40% (6/15) of patients with HCC resistant to pembrolizumab exhibited tumorous PPARγ induction. Moreover, higher baseline PPARγ expression was associated with poorer survival of anti-PD-(L)1-treated patients in multiple cancer types. CONCLUSION: We uncover an adaptive transcriptional programme by which tumour cells evade immune-checkpoint targeting via PPARγ/VEGF-A-mediated TME immunosuppression, thus providing a strategy for counteracting immunotherapeutic resistance in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Carcinoma Hepatocelular/patologia , Fator A de Crescimento do Endotélio Vascular , Neoplasias Hepáticas/patologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , PPAR gama , Microambiente Tumoral , Antígeno B7-H1
10.
Nat Genet ; 55(2): 178-186, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36658435

RESUMO

Precision medicine promises to transform healthcare for groups and individuals through early disease detection, refining diagnoses and tailoring treatments. Analysis of large-scale genomic-phenotypic databases is a critical enabler of precision medicine. Although Asia is home to 60% of the world's population, many Asian ancestries are under-represented in existing databases, leading to missed opportunities for new discoveries, particularly for diseases most relevant for these populations. The Singapore National Precision Medicine initiative is a whole-of-government 10-year initiative aiming to generate precision medicine data of up to one million individuals, integrating genomic, lifestyle, health, social and environmental data. Beyond technologies, routine adoption of precision medicine in clinical practice requires social, ethical, legal and regulatory barriers to be addressed. Identifying driver use cases in which precision medicine results in standardized changes to clinical workflows or improvements in population health, coupled with health economic analysis to demonstrate value-based healthcare, is a vital prerequisite for responsible health system adoption.


Assuntos
Atenção à Saúde , Medicina de Precisão , Humanos , Singapura , Medicina de Precisão/métodos , Ásia
11.
Mol Ther ; 31(1): 119-133, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36146933

RESUMO

The local microenvironment where tumors develop can shape cancer progression and therapeutic outcome. Emerging evidence demonstrate that the efficacy of immune-checkpoint blockade (ICB) is undermined by fibrotic tumor microenvironment (TME). The majority of hepatocellular carcinoma (HCC) develops in liver fibrosis, in which the stromal and immune components may form a barricade against immunotherapy. Here, we report that nanodelivery of a programmed death-ligand 1 (PD-L1) trap gene exerts superior efficacy in treating fibrosis-associated HCC when compared with the conventional monoclonal antibody (mAb). In two fibrosis-associated HCC models induced by carbon tetrachloride and a high-fat, high-carbohydrate diet, the PD-L1 trap induced significantly larger tumor regression than mAb with no evidence of toxicity. Mechanistic studies revealed that PD-L1 trap, but not mAb, consistently reduced the M2 macrophage proportion in the fibrotic liver microenvironment and promoted cytotoxic interferon gamma (IFNγ)+tumor necrosis factor α (TNF-α)+CD8+T cell infiltration to the tumor. Moreover, PD-L1 trap treatment was associated with decreased tumor-infiltrating polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) accumulation, resulting in an inflamed TME with a high cytotoxic CD8+T cell/PMN-MDSC ratio conductive to anti-tumor immune response. Single-cell RNA sequencing analysis of two clinical cohorts demonstrated preferential PD-L1 expression in M2 macrophages in the fibrotic liver, thus supporting the translational potential of nano-PD-L1 trap for fibrotic HCC treatment.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Antineoplásicos/uso terapêutico , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Cirrose Hepática/etiologia , Cirrose Hepática/tratamento farmacológico , Microambiente Tumoral
12.
Oncogene ; 41(36): 4200-4210, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35882981

RESUMO

Large-scale fecal shotgun metagenomic sequencing revealed the high abundance of Parvimonas micra in colorectal cancer (CRC) patients. We investigated the role and clinical significance of P. micra in colorectal tumorigenesis. The abundance of P. micra was examined in 309 fecal samples and 165 colon biopsy tissues of CRC patients and healthy subjects. P. micra was significantly enriched in fecal samples from 128 CRC patients compared to 181 healthy subjects (P < 0.0001); and in colon tissue biopsies from 52 CRC patients compared to 61 healthy subjects (P < 0.0001). Multivariate analysis showed that P. micra is an independent risk factor of poor survival in CRC patients (Hazard Ratio: 1.93). P. micra strain was isolated from feces of a CRC patient. Apcmin/+ mice gavaged with P. micra showed significantly higher tumor burden and tumor load (both P < 0.01). Consistently, gavage of P. micra significantly promoted colonocyte proliferation in conventional mice, which was further confirmed by germ-free mice. P. micra colonization up-regulated genes involved in cell proliferation, stemness, angiogenesis and invasiveness/metastasis; and enhanced Th17 cells infiltration and expression of Th17 cells-secreted cytokines (Il-17, Il-22, and Il-23) in the colon of Apcmin/+, conventional and germ-free mice. P. micra-conditioned medium significantly promoted the differentiation of CD4+ T cells to Th17 cells (IL-17+CD4+ phenotype) and enhanced the oncogenic Wnt signaling pathway. In conclusion, P. micra promoted colorectal tumorigenesis in mice by inducing colonocyte proliferation and altering Th17 immune response. P. micra may act as a prognostic biomarker for poor survival of CRC patients.


Assuntos
Neoplasias Colorretais , Interleucina-17 , Animais , Carcinogênese/genética , Proliferação de Células , Neoplasias Colorretais/patologia , Firmicutes , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-17/metabolismo , Camundongos
13.
Gastroenterology ; 163(4): 908-921, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35724733

RESUMO

BACKGROUND & AIMS: The enteric mycobiota is a major component of the human gut microbiota, but its role in colorectal cancer (CRC) remains largely elusive. We conducted a meta-analysis to uncover the contribution of the fungal mycobiota to CRC. METHODS: We retrieved fecal metagenomic data sets from 7 previous publications and established an additional in-house cohort, totaling 1329 metagenomes (454 with CRC, 350 with adenoma, and 525 healthy individuals). Mycobiota composition and microbial interactions were analyzed. Candidate CRC-enriched fungal species (Aspergillus rambellii) was functionally validated in vitro and in vivo. RESULTS: Multicohort analysis revealed that the enteric mycobiota was altered in CRC. We identified fungi that were associated with patients with CRC or adenoma from multiple cohorts. Signature CRC-associated fungi included 6 enriched (A rambellii, Cordyceps sp. RAO-2017, Erysiphe pulchra, Moniliophthora perniciosa, Sphaerulina musiva, and Phytophthora capsici) and 1 depleted species (A kawachii). Co-occurrent interactions among CRC-enriched fungi became stronger in CRC compared with adenoma and healthy individuals. Moreover, we reported the transkingdom interactions between enteric fungi and bacteria in CRC progression, of which A rambellii was closely associated with CRC-enriched bacteria Fusobacterium nucleatum. A rambellii promoted CRC cell growth in vitro and tumor growth in xenograft mice. We further identified that combined fungal and bacterial biomarkers were more accurate than panels with pure bacterial species to discriminate patients with CRC from healthy individuals (the area under the curve relative change increased by 1.44%-10.60%). CONCLUSIONS: This study reveals enteric mycobiota signatures and pathogenic fungi in stages of colorectal tumorigenesis. Fecal fungi can be used, in addition to bacteria, for noninvasive diagnosis of patients with CRC.


Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/microbiologia , Animais , Aspergillus , Bactérias/genética , Biomarcadores , Transformação Celular Neoplásica , Neoplasias Colorretais/diagnóstico , Fezes/microbiologia , Humanos , Metagenoma , Camundongos
14.
Gastroenterology ; 163(3): 699-711, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35679948

RESUMO

BACKGROUND & AIMS: Lack of viral reference genomes poses a challenge to virome study. We investigated human gut virome and its clinical implication by ultra-deep metagenomic sequencing. METHODS: We extracted sufficient viral DNA from human feces for ultra-deep PacBio sequencing (>10 µg) and Illumina sequencing (>1 µg). Upon de novo assembly and 6 stages of strict filtering, viral genomes were generated and validated in 3 cohorts of 2819 published fecal metagenomes. Diagnostic performance of assembled viruses for colorectal cancer were tested in a training cohort and 2 independent validation cohorts. Virus mapping ratio, evolutionary history, and virus status (lytic or temperate) were also examined. RESULTS: The mean amount of extracted viral DNA increased by 14-fold compared with previous protocols. We obtained PacBio long reads and Illumina short reads with 290-fold higher depth than previous studies. We assembled and validated 1178 contigs as complete viral genomes, of which 1058 were newly identified. Thirteen viral genomes (398-839 kb) that are longer than the largest bacteriophage found in humans (393 kb) were discovered. Phylogenetic tree was constructed based on Hidden Markov Models alignment scores of 4 conserved viral proteins. Incorporating our assembled genomes into the National Center for Biotechnology Information database improved the mapping ratio of published metagenomes ≤18 times. Lytic viruses (75.9% ± 12.2% of total) were predominantly present in our sample. A biomarker panel of 14 novel viruses could discriminate patients with colorectal cancer from controls with an area under the receiver operating characteristics curve of 0.87 in the training cohort, which was validated with areas under the receiver operating characteristics curve of 0.85 and 0.73 in 2 independent cohorts. CONCLUSIONS: We uncovered 1058 novel human gut viruses. These findings can contribute to clinical diagnosis, current viral reference genome, and future virome investigation.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Vírus , Neoplasias Colorretais/genética , Vírus de DNA/genética , DNA Viral/genética , Humanos , Metagenoma , Metagenômica/métodos , Filogenia , Vírus/genética
15.
Oncogene ; 41(28): 3599-3610, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35680985

RESUMO

The consistency of the associations between gastric mucosal microbiome and gastric cancer across studies remained unexamined. We aimed to identify universal microbial signatures in gastric carcinogenesis through a meta-analysis of gastric microbiome from multiple studies. Compositional and ecological profiles of gastric microbes across stages of gastric carcinogenesis were significantly altered. Meta-analysis revealed that opportunistic pathobionts Fusobacterium, Parvimonas, Veillonella, Prevotella and Peptostreptococcus were enriched in GC, while commensals Bifidobacterium, Bacillus and Blautia were depleted in comparison to SG. The co-occurring correlation strengths of GC-enriched bacteria were increased along disease progression while those of GC-depleted bacteria were decreased. Eight bacterial taxa, including Veillonella, Dialister, Granulicatella, Herbaspirillum, Comamonas, Chryseobacterium, Shewanella and Helicobacter, were newly identified by this study as universal biomarkers for robustly discriminating GC from SG, with an area under the curve (AUC) of 0.85. Moreover, H. pylori-positive samples exhibited reduced microbial diversity, altered microbiota community and weaker interactions among gastric microbes. Our meta-analysis demonstrated comprehensive and generalizable gastric mucosa microbial features associated with histological stages of gastric carcinogenesis, including GC associated bacteria, diagnostic biomarkers, bacterial network alteration and H. pylori influence.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Microbiota , Neoplasias Gástricas , Carcinogênese/patologia , Disbiose/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/complicações , Humanos , Estômago/patologia , Neoplasias Gástricas/patologia
16.
Adv Mater ; 34(34): e2201888, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35474246

RESUMO

Biofilm eradication from medical implants is of fundamental importance, and the treatment of biofilm-associated pathogen infections on inaccessible biliary stents remains challenging. Magnetically driven microrobots with controlled motility, accessibility to the tiny lumen, and swarm enhancement effects can physically disrupt the deleterious biostructures while not developing drug resistance. Magnetic urchin-like capsule robots (MUCRs) loaded with magnetic liquid metal droplets (MLMDs, antibacterial agents) are designed using natural sunflower pollen, and the therapeutic effect of swarming MUCR@MLMDs is explored for eradicating complex mixtures of bacterial biofilm within biliary stents collected from patients. The external magnetic field triggers the emergence of the microswarm and induces MLMDs to transform their shape into spheroids and rods with sharp edges. The inherent natural microspikes of MUCRs and the obtained sharp edges of MLMDs actively rupture the dense biological matrix and multiple species of embedded bacterial cells by exerting mechanical force, finally achieving synergistic biofilm eradication. The microswarm is precisely and rapidly deployed into the biliary stent via endoscopy in 10 min. Notably, fluoroscopy imaging is used to track and navigate the locomotion of microswarm in biliary stents in real-time. The microswarm has great potential for treating bacterial biofilm infections associated with medical implants.


Assuntos
Infecções Bacterianas , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Fluoroscopia , Humanos , Fenômenos Magnéticos , Stents/microbiologia
17.
J Cachexia Sarcopenia Muscle ; 12(6): 1393-1407, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34523250

RESUMO

BACKGROUND: Gut microbiota dysbiosis and sarcopenia commonly occur in the elderly. Although the concept of the gut-muscle axis has been raised, the casual relationship is still unclear. This systematic review analyses the current evidence of gut microbiota effects on muscle/sarcopenia. METHODS: A systematic review was performed in PubMed, Embase, Web of Science, and The Cochrane Library databases using the keywords (microbiota* OR microbiome*) AND (sarcopen* OR muscle). Studies reporting the alterations of gut microbiota and muscle/physical performance were analysed. RESULTS: A total of 26 pre-clinical and 10 clinical studies were included. For animal studies, three revealed age-related changes and relationships between gut microbiota and muscle. Three studies focused on muscle characteristics of germ-free mice. Seventy-five per cent of eight faecal microbiota transplantation studies showed that the recipient mice successfully replicated the muscle phenotype of donors. There were positive effects on muscle from seven probiotics, two prebiotics, and short-chain fatty acids (SCFAs). Ten studies investigated on other dietary supplements, antibiotics, exercise, and food withdrawal that affected both muscle and gut microbiota. Twelve studies explored the potential mechanisms of the gut-muscle axis. For clinical studies, 6 studies recruited 676 elderly people (72.8 ± 5.6 years, 57.8% female), while 4 studies focused on 244 young adults (29.7 ± 7.8 years, 55.4% female). The associations of gut microbiota and muscle had been shown in four observational studies. Probiotics, prebiotics, synbiotics, fermented milk, caloric restriction, and exercise in six studies displayed inconsistent effects on muscle mass, function, and gut microbiota. CONCLUSIONS: Altering the gut microbiota through bacteria depletion, faecal transplantation, and various supplements was shown to directly affect muscle phenotypes. Probiotics, prebiotics, SCFAs, and bacterial products are potential novel therapies to enhance muscle mass and physical performance. Lactobacillus and Bifidobacterium strains restored age-related muscle loss. Potential mechanisms of microbiome modulating muscle mainly include protein, energy, lipid, and glucose metabolism, inflammation level, neuromuscular junction, and mitochondrial function. The role of the gut microbiota in the development of muscle loss during aging is a crucial area that requires further studies for translation to patients.


Assuntos
Microbioma Gastrointestinal , Sarcopenia , Simbióticos , Idoso , Animais , Transplante de Microbiota Fecal , Feminino , Humanos , Masculino , Camundongos , Prebióticos , Sarcopenia/etiologia , Sarcopenia/terapia
18.
Sci Robot ; 6(52)2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-34043547

RESUMO

High-precision delivery of microrobots at the whole-body scale is of considerable importance for efforts toward targeted therapeutic intervention. However, vision-based control of microrobots, to deep and narrow spaces inside the body, remains a challenge. Here, we report a soft and resilient magnetic cell microrobot with high biocompatibility that can interface with the human body and adapt to the complex surroundings while navigating inside the body. We achieve time-efficient delivery of soft microrobots using an integrated platform called endoscopy-assisted magnetic actuation with dual imaging system (EMADIS). EMADIS enables rapid deployment across multiple organ/tissue barriers at the whole-body scale and high-precision delivery of soft and biohybrid microrobots in real time to tiny regions with depth up to meter scale through natural orifice, which are commonly inaccessible and even invisible by conventional endoscope and medical robots. The precise delivery of magnetic stem cell spheroid microrobots (MSCSMs) by the EMADIS transesophageal into the bile duct with a total distance of about 100 centimeters can be completed within 8 minutes. The integration strategy offers a full clinical imaging technique-based therapeutic/intervention system, which broadens the accessibility of hitherto hard-to-access regions, by means of soft microrobots.


Assuntos
Sistemas de Liberação de Medicamentos/instrumentação , Endoscopia/instrumentação , Robótica/instrumentação , Células 3T3 , Animais , Sistemas Computacionais , Diagnóstico por Imagem/instrumentação , Desenho de Equipamento , Feminino , Humanos , Magnetismo/instrumentação , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Microtecnologia , Cirurgia Endoscópica por Orifício Natural/instrumentação , Ratos , Ratos Sprague-Dawley , Esferoides Celulares/transplante , Sus scrofa , Ultrassonografia
19.
Sci Transl Med ; 13(588)2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827976

RESUMO

Insufficient T cell infiltration into noninflamed tumors, such as hepatocellular carcinoma (HCC), restricts the effectiveness of immune-checkpoint blockade (ICB) for a subset of patients. Epigenetic therapy provides further opportunities to rewire cancer-associated transcriptional programs, but whether and how selective epigenetic inhibition counteracts the immune-excluded phenotype remain incompletely defined. Here, we showed that pharmacological inhibition of histone deacetylase 8 (HDAC8), a histone H3 lysine 27 (H3K27)-specific isozyme overexpressed in a variety of human cancers, thwarts HCC tumorigenicity in a T cell-dependent manner. The tumor-suppressive effect of selective HDAC8 inhibition was abrogated by CD8+ T cell depletion or regulatory T cell adoptive transfer. Chromatin profiling of human HDAC8-expressing HCCs revealed genome-wide H3K27 deacetylation in 1251 silenced enhancer-target gene pairs that are enriched in metabolic and immune regulators. Mechanistically, down-regulation of HDAC8 increased global and enhancer acetylation of H3K27 to reactivate production of T cell-trafficking chemokines by HCC cells, thus relieving T cell exclusion in both immunodeficient and humanized mouse models. In an HCC preclinical model, selective HDAC8 inhibition increased tumor-infiltrating CD8+ T cells and potentiated eradication of established hepatomas by anti-PD-L1 therapy without evidence of toxicity. Mice treated with HDAC8 and PD-L1 coblockade were protected against subsequent tumor rechallenge as a result of the induction of memory T cells and remained tumor-free for greater than 15 months. Collectively, our study demonstrates that selective HDAC8 inhibition elicits effective and durable responses to ICB by co-opting adaptive immunity through enhancer reprogramming.


Assuntos
Carcinoma Hepatocelular , Inibidores de Histona Desacetilases , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Animais , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/imunologia , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/imunologia , Camundongos , Proteínas Repressoras
20.
JHEP Rep ; 3(2): 100224, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33604533

RESUMO

BACKGROUND & AIMS: Immune checkpoint blockade (ICB) has been approved for treatment of hepatocellular carcinoma (HCC). However, many patients with advanced HCC are non-responders to ICB monotherapy. Cytotoxic chemotherapy has been proposed to modulate the tumor microenvironment (TME) and sensitize tumors to ICB. Thus, we aimed to study the combination of cytotoxic chemotherapy and ICB in an orthotopic HCC model. METHODS: Preclinical orthotopic HCC mouse models were used to elucidate the efficacy of 5-fluorouracil (5-FU) and ICB. The mice were intrahepatically injected with RIL-175 or Hepa1-6 cells, followed by treatment with 5-FU and anti-programmed cell death ligand 1 (PD-L1) antibody. Myeloid-derived suppressor cells (MDSCs) were depleted to validate their role in attenuating sensitivity to immunotherapy. Flow cytometry-based immune profiling and immunofluorescence staining were performed in mice and patient samples, respectively. RESULTS: 5-FU could induce intratumoral MDSC accumulation to counteract the infiltration of T lymphocytes and natural killer cells, thus abrogating the anti-tumor efficacy of PD-L1 blockade. In clinical samples, MDSCs accumulated and CD8+ T cell numbers decreased following transarterial chemoembolization. CONCLUSION: 5-FU can trigger the accumulation of immunosuppressive MDSCs, impairing the response to PD-L1 blockade in HCC. Our data suggest that the combination of specific chemotherapy and ICB may impair anti-tumor immune responses, warranting further study in preclinical models and consideration in clinical settings. LAY SUMMARY: Our findings suggest that some chemotherapies may impair the anti-tumor efficacy of immunotherapy. Further studies are required to uncover the specific effects of different chemotherapies on the immunological profile of tumors. This data will be critical for the rational design of combination immunotherapy strategies for patients with hepatocellular carcinoma.

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