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1.
Br J Anaesth ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267338

RESUMO

BACKGROUND: Dexamethasone has been shown to reduce acute pain after surgery, but there is uncertainty as to its effects on chronic postsurgical pain (CPSP). We hypothesised that in patients undergoing major noncardiac surgery, a single intraoperative dose of dexamethasone increases the incidence of CPSP. METHODS: We devised a propensity score-matched analysis of the ENIGMA-II trial CPSP dataset, aiming to compare the incidence of CPSP in patients who had received dexamethasone or not 12 months after major noncardiac surgery. The primary outcome was the incidence of CPSP. We used propensity score matching and inverse probability weighting to balance baseline variables to estimate the average marginal effect of dexamethasone on patient outcomes, accounting for confounding to estimate the average treatment effect on those treated with dexamethasone. RESULTS: We analysed 2999 patients, of whom 116 of 973 (11.9%) receiving dexamethasone reported CPSP, and 380 of 2026 (18.8%) not receiving dexamethasone reported CPSP, unadjusted odds ratio 0.76 (95% confidence interval 0.78-1.00), P=0.052. After propensity score matching, CPSP occurred in 116 of 973 patients (12.2%) receiving dexamethasone and 380 of 2026 patients (13.8%) not receiving dexamethasone, adjusted risk ratio 0.88 (95% confidence interval 0.61-1.27), P=0.493. There was no difference between groups in quality of life or pain interference with daily activities, but 'least pain' (P=0.033) and 'pain right now' (P=0.034) were higher in the dexamethasone group. CONCLUSIONS: Dexamethasone does not increase the risk of chronic postsurgical pain after major noncardiac surgery. CLINICAL TRIAL REGISTRATION: Open Science Framework Registration DOI https://doi.org/10.17605/OSF.IO/ZDVB5.

2.
Nat Commun ; 15(1): 669, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38253620

RESUMO

The role of N6-methyladenosine (m6A) modification of host mRNA during bacterial infection is unclear. Here, we show that Helicobacter pylori infection upregulates host m6A methylases and increases m6A levels in gastric epithelial cells. Reducing m6A methylase activity via hemizygotic deletion of methylase-encoding gene Mettl3 in mice, or via small interfering RNAs targeting m6A methylases, enhances H. pylori colonization. We identify LOX-1 mRNA as a key m6A-regulated target during H. pylori infection. m6A modification destabilizes LOX-1 mRNA and reduces LOX-1 protein levels. LOX-1 acts as a membrane receptor for H. pylori catalase and contributes to bacterial adhesion. Pharmacological inhibition of LOX-1, or genetic ablation of Lox-1, reduces H. pylori colonization. Moreover, deletion of the bacterial catalase gene decreases adhesion of H. pylori to human gastric sections. Our results indicate that m6A modification of host LOX-1 mRNA contributes to protection against H. pylori infection by downregulating LOX-1 and thus reducing H. pylori adhesion.


Assuntos
Adenosina , Infecções por Helicobacter , Helicobacter pylori , Receptores Depuradores Classe E , Animais , Humanos , Camundongos , Adenosina/análogos & derivados , Catalase/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/metabolismo , RNA Mensageiro/genética , Receptores Depuradores Classe E/genética
4.
Clin Transl Med ; 13(12): e1516, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38148640

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs), integral to the tumour microenvironment, are pivotal in cancer progression, exhibiting either pro-tumourigenic or anti-tumourigenic functions. Their inherent phenotypic and functional diversity allows for the subdivision of CAFs into various subpopulations. While several classification systems have been suggested for different cancer types, a unified molecular classification of CAFs on a single-cell pan-cancer scale has yet to be established. METHODS: We employed a comprehensive single-cell transcriptomic atlas encompassing 12 solid tumour types. Our objective was to establish a novel molecular classification and to elucidate the evolutionary trajectories of CAFs. We investigated the functional profiles of each CAF subtype using Single-Cell Regulatory Network Inference and Clustering and single-cell gene set enrichment analysis. The clinical relevance of these subtypes was assessed through survival curve analysis. Concurrently, we employed multiplex immunofluorescence staining on tumour tissues to determine the dynamic changes of CAF subtypes across different tumour stages. Additionally, we identified the small molecule procyanidin C1 (PCC1) as a target for matrix-producing CAF (matCAF) using molecular docking techniques and further validated these findings through in vitro and in vivo experiments. RESULTS: In our investigation of solid tumours, we identified four molecular clusters of CAFs: progenitor CAF (proCAF), inflammatory CAF (iCAF), myofibroblastic CAF (myCAF) and matCAF, each characterised by distinct molecular traits. This classification was consistently applicable across all nine studied solid tumour types. These CAF subtypes displayed unique evolutionary pathways, functional roles and clinical relevance in various solid tumours. Notably, the matCAF subtype was associated with poorer prognoses in several cancer types. The targeting of matCAF using the identified small molecule, PCC1, demonstrated promising antitumour activity. CONCLUSIONS: Collectively, the various subtypes of CAFs, particularly matCAF, are crucial in the initiation and progression of cancer. Focusing therapeutic strategies on targeting matCAF in solid tumours holds significant potential for cancer treatment.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Humanos , Fibroblastos Associados a Câncer/metabolismo , Simulação de Acoplamento Molecular , Neoplasias/patologia , Perfilação da Expressão Gênica , Transcriptoma/genética , Microambiente Tumoral/genética
5.
Clin Transl Med ; 13(11): e1481, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37983931

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the most common tumours in East Asia countries and is associated with Helicobacter pylori infection. H. pylori utilizes virulence factors, CagA and VacA, to up-regulate pro-inflammatory cytokines and activate NF-κB signaling. Meanwhile, the PIEZO1 upregulation and cancer-associated fibroblast (CAF) enrichment were found in GC progression. However, the mechanisms of PIEZO1 upregulation and its involvement in GC progression have not been fully elucidated. METHODS: The CAF enrichment and clinical significance were investigated in animal models and primary samples. The expression of NF-κB and PIEZO1 in GC was confirmed by immunohistochemistry staining, and expression correlation was analysed in multiple GC datasets. GSEA and Western blot analysis revealed the YAP1-CTGF axis regulation by PIEZO1. The stimulatory effects of CTGF on CAFs were validated by the co-culture system and animal studies. Patient-derived organoid and peritoneal dissemination models were employed to confirm the role of the PIEZO1-YAP1-CTGF cascade in GC. RESULTS: Both CAF signature and PIEZO1 were positively correlated with H. pylori infection. PIEZO1, a mechanosensor, was confirmed as a direct downstream of NF-κB to promote the transformation from intestinal metaplasia to GC. Mechanistic studies revealed that PIEZO1 transduced the oncogenic signal from NF-κB into YAP1 signaling, a well-documented oncogenic pathway in GC progression. PIEZO1 expression was positively correlated with the YAP1 signature (CTGF, CYR61, and c-Myc, etc.) in primary samples. The secreted CTGF by cancer cells stimulated the CAF infiltration to form a stiffened collagen-enrichment microenvironment, thus activating PIEZO1 to form a positive feedback loop. Both PIEZO1 depletion by shRNA and CTGF inhibition by Procyanidin C1 enhanced the efficacy of 5-FU in suppressing the GC cell peritoneal metastasis. CONCLUSION: This study elucidates a novel driving PIEZO1-YAP1-CTGF force, which opens a novel therapeutic avenue to block the transformation from precancerous lesions to GC. H. pylori-NF-κB activates the PIEZO1-YAP1-CTGF axis to remodel the GC microenvironment by promoting CAF infiltration. Targeting PIEZO1-YAP1-CTGF plus chemotherapy might serve as a potential therapeutic option to block GC progression and peritoneal metastasis.


Assuntos
Fibroblastos Associados a Câncer , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Peritoneais , Neoplasias Gástricas , Animais , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Neoplasias Gástricas/patologia , Helicobacter pylori/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Microambiente Tumoral/genética , Canais Iônicos
7.
EBioMedicine ; 93: 104670, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37343363

RESUMO

BACKGROUND: Obesity is a risk factor for colorectal cancer (CRC). The role of gut microbiota in mediating the cancer-promoting effect of obesity is unknown. METHODS: Azoxymethane (AOM)-treated, ApcMin/+ and germ-free mice were gavaged with feces from obese individuals and control subjects respectively. The colonic tumor load and number were recorded at the endpoint in two carcinogenic models. The gut microbiota composition and colonic transcriptome were assessed by metagenomic sequencing and RNA sequencing, respectively. The anticancer effects of bacteria depleted in fecal samples of obese individuals were validated. FINDINGS: Conventional AOM-treated and ApcMin/+ mice receiving feces from obese individuals showed significantly increased colon tumor formation compared with those receiving feces from control subjects. AOM-treated mice receiving feces from obese individuals showed impaired intestinal barrier function and significant upregulation of pro-inflammatory cytokines and activation of oncogenic Wnt signaling pathway. Consistently, transferring feces from obese individuals to germ-free mice led to increased colonic cell proliferation, intestinal barrier function impairment, and induction of oncogenic and proinflammatory gene expression. Moreover, germ-free mice transplanted with feces from obese human donors had increased abundance of potential pathobiont Alistipes finegoldii, and reduced abundance of commensals Bacteroides vulgatus and Akkermansia muciniphila compared with those receiving feces from human donors with normal body mass index (BMI). Validation experiments showed that B. vulgatus and A. muciniphila demonstrated anti-proliferative effects in CRC, while A. finegoldii promoted CRC tumor growth. INTERPRETATION: Our results supported the role of obesity-associated microbiota in colorectal carcinogenesis and identified putative bacterial candidates that may mediate its mechanisms. Microbiota modulation in obese individuals may provide new approaches to prevent or treat obesity-related cancers including CRC. FUNDING: This work was funded by National Key Research and Development Program of China (2020YFA0509200/2020YFA0509203), National Natural Science Foundation of China (81922082), RGC Theme-based Research Scheme Hong Kong (T21-705/20-N), RGC Research Impact Fund Hong Kong (R4632-21F), RGC-CRF Hong Kong (C4039-19GF and C7065-18GF), RGC-GRF Hong Kong (14110819, 14111621), and NTU Start-Up Grant (021337-00001).


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Carcinogênese , Obesidade/complicações , Azoximetano/toxicidade , Neoplasias Colorretais/genética , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
8.
Theranostics ; 12(15): 6509-6526, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185598

RESUMO

Rationale: Hyperactivation of Hippo-Yes-associated protein (YAP) signaling pathway governs tumorigenesis of gastric cancer (GC). Here we reveal that minichromosome maintenance complex component 6 (MCM6) is a critical transcriptional target of YAP in GC. We aim to investigate the function, mechanism of action, and clinical implication of MCM6 in GC. Methods: The downstream targets of YAP were screened by RNA sequencing (RNA-seq) and microarray, and further validated by chromatin immunoprecipitation PCR and luciferase reporter assays. The clinical implication of MCM6 was assessed in multiple GC cohorts. Biological function of MCM6 was evaluated in vitro, in patient-derived organoids, and in vivo. RNA-seq was performed to unravel downstream signaling of MCM6. Potential MCM6 inhibitor was identified and the effect of MCM6 inhibition on GC growth was evaluated. Results: Integrative RNA sequencing and microarray analyses revealed MCM6 as a potential YAP downstream target in GC. The YAP-TEAD complex bound to the promoter of MCM6 to induce its transcription. Increased MCM6 expression was commonly observed in human GC tissues and predicted poor patients survival. MCM6 knockdown suppressed proliferation and migration of GC cells and patient-derived organoids, and attenuated xenograft growth and peritoneal metastasis in mice. Mechanistically, MCM6 activated PI3K/Akt/GSK3ß signaling to support YAP-potentiated gastric tumorigenicity and metastasis. Furthermore, MCM6 deficiency sensitized GC cells to chemo- or radiotherapy by causing DNA breaks and blocking ATR/Chk1-mediated DNA damage response (DDR), leading to exacerbated cell death and tumor regression. As there are no available MCM6 inhibitors, we performed high-throughput virtual screening and identified purpureaside C as a novel MCM6 inhibitor. Purpureaside C not only suppressed GC growth but also synergized with 5-fluorouracil to induce cell death. Conclusions: Hyperactivated YAP in GC induces MCM6 transcription via binding to its promoter. YAP-MCM6 axis facilitates GC progression by inducing PI3K/Akt signaling. Targeting MCM6 suppresses GC growth and sensitizes GC cells to genotoxic agents by modulating ATR/Chk1-dependent DDR, providing a promising strategy for GC treatment.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias Gástricas , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Fluoruracila/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Camundongos , Componente 6 do Complexo de Manutenção de Minicromossomo/genética , Componente 6 do Complexo de Manutenção de Minicromossomo/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/patologia , Proteínas de Sinalização YAP
9.
N Engl J Med ; 386(21): 1986-1997, 2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35363452

RESUMO

BACKGROUND: Perioperative bleeding is common in patients undergoing noncardiac surgery. Tranexamic acid is an antifibrinolytic drug that may safely decrease such bleeding. METHODS: We conducted a trial involving patients undergoing noncardiac surgery. Patients were randomly assigned to receive tranexamic acid (1-g intravenous bolus) or placebo at the start and end of surgery (reported here) and, with the use of a partial factorial design, a hypotension-avoidance or hypertension-avoidance strategy (not reported here). The primary efficacy outcome was life-threatening bleeding, major bleeding, or bleeding into a critical organ (composite bleeding outcome) at 30 days. The primary safety outcome was myocardial injury after noncardiac surgery, nonhemorrhagic stroke, peripheral arterial thrombosis, or symptomatic proximal venous thromboembolism (composite cardiovascular outcome) at 30 days. To establish the noninferiority of tranexamic acid to placebo for the composite cardiovascular outcome, the upper boundary of the one-sided 97.5% confidence interval for the hazard ratio had to be below 1.125, and the one-sided P value had to be less than 0.025. RESULTS: A total of 9535 patients underwent randomization. A composite bleeding outcome event occurred in 433 of 4757 patients (9.1%) in the tranexamic acid group and in 561 of 4778 patients (11.7%) in the placebo group (hazard ratio, 0.76; 95% confidence interval [CI], 0.67 to 0.87; absolute difference, -2.6 percentage points; 95% CI, -3.8 to -1.4; two-sided P<0.001 for superiority). A composite cardiovascular outcome event occurred in 649 of 4581 patients (14.2%) in the tranexamic acid group and in 639 of 4601 patients (13.9%) in the placebo group (hazard ratio, 1.02; 95% CI, 0.92 to 1.14; upper boundary of the one-sided 97.5% CI, 1.14; absolute difference, 0.3 percentage points; 95% CI, -1.1 to 1.7; one-sided P = 0.04 for noninferiority). CONCLUSIONS: Among patients undergoing noncardiac surgery, the incidence of the composite bleeding outcome was significantly lower with tranexamic acid than with placebo. Although the between-group difference in the composite cardiovascular outcome was small, the noninferiority of tranexamic acid was not established. (Funded by the Canadian Institutes of Health Research and others; POISE-3 ClinicalTrials.gov number, NCT03505723.).


Assuntos
Antifibrinolíticos , Ácido Tranexâmico , Antifibrinolíticos/efeitos adversos , Antifibrinolíticos/uso terapêutico , Canadá , Hemorragia/etiologia , Hemorragia/prevenção & controle , Humanos , Procedimentos Cirúrgicos Operatórios , Trombose/induzido quimicamente , Trombose/tratamento farmacológico , Ácido Tranexâmico/efeitos adversos , Ácido Tranexâmico/uso terapêutico
10.
Trials ; 23(1): 101, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35101083

RESUMO

BACKGROUND: For patients undergoing noncardiac surgery, bleeding and hypotension are frequent and associated with increased mortality and cardiovascular complications. Tranexamic acid (TXA) is an antifibrinolytic agent with the potential to reduce surgical bleeding; however, there is uncertainty about its efficacy and safety in noncardiac surgery. Although usual perioperative care is commonly consistent with a hypertension-avoidance strategy (i.e., most patients continue their antihypertensive medications throughout the perioperative period and intraoperative mean arterial pressures of 60 mmHg are commonly accepted), a hypotension-avoidance strategy may improve perioperative outcomes. METHODS: The PeriOperative Ischemic Evaluation (POISE)-3 Trial is a large international randomized controlled trial designed to determine if TXA is superior to placebo for the composite outcome of life-threatening, major, and critical organ bleeding, and non-inferior to placebo for the occurrence of major arterial and venous thrombotic events, at 30 days after randomization. Using a partial factorial design, POISE-3 will additionally determine the effect of a hypotension-avoidance strategy versus a hypertension-avoidance strategy on the risk of major cardiovascular events, at 30 days after randomization. The target sample size is 10,000 participants. Patients ≥45 years of age undergoing noncardiac surgery, with or at risk of cardiovascular and bleeding complications, are randomized to receive a TXA 1 g intravenous bolus or matching placebo at the start and at the end of surgery. Patients, health care providers, data collectors, outcome adjudicators, and investigators are blinded to the treatment allocation. Patients on ≥ 1 chronic antihypertensive medication are also randomized to either of the two blood pressure management strategies, which differ in the management of patient antihypertensive medications on the morning of surgery and on the first 2 days after surgery, and in the target mean arterial pressure during surgery. Outcome adjudicators are blinded to the blood pressure treatment allocation. Patients are followed up at 30 days and 1 year after randomization. DISCUSSION: Bleeding and hypotension in noncardiac surgery are common and have a substantial impact on patient prognosis. The POISE-3 trial will evaluate two interventions to determine their impact on bleeding, cardiovascular complications, and mortality. TRIAL REGISTRATION: ClinicalTrials.gov NCT03505723. Registered on 23 April 2018.


Assuntos
Antifibrinolíticos , Hipotensão , Ácido Tranexâmico , Antifibrinolíticos/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Humanos , Hipotensão/induzido quimicamente , Hipotensão/diagnóstico , Hipotensão/prevenção & controle , Assistência Perioperatória , Ácido Tranexâmico/efeitos adversos
11.
Gut ; 71(8): 1544-1550, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34548338

RESUMO

OBJECTIVE: While it is recommended that patients presenting with acute upper gastrointestinal bleeding (AUGIB) should receive endoscopic intervention within 24 hours, the optimal timing is still uncertain. We aimed to assess whether endoscopy timing postadmission would affect outcomes. DESIGN: We conducted a retrospective, territory-wide, cohort study with healthcare data from all public hospitals in Hong Kong. Adult patients (age ≥18) that presented with AUGIB between 2013 and 2019 and received therapeutic endoscopy within 48 hours (n=6474) were recruited. Patients were classified based on endoscopic timing postadmission: urgent (t≤6), early (6

Assuntos
Endoscopia Gastrointestinal , Hemorragia Gastrointestinal , Doença Aguda , Adulto , Estudos de Coortes , Endoscopia Gastrointestinal/métodos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Humanos , Estudos Retrospectivos
13.
Int J Med Robot ; 17(5): e2300, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34109730

RESUMO

BACKGROUND: Robotic-assisted total knee arthroplasty (TKA) was performed to promote the accuracy of bone resection and mechanical alignment. Among these TKA system procedures, 3D reconstruction of CT data of lower limbs consumes significant manpower. Artificial intelligence (AI) algorithms applying deep learning has been proved efficient in automated identification and visual processing. METHODS: CT data of a total of 200 lower limbs scanning were used for AI-based 3D model construction and CT data of 20 lower limbs scanning were utilised for verification. RESULTS: We showed that the performance of an AI-guided 3D reconstruction of CT data of lower limbs for robotic-assisted TKA was similar to that of the operator-based approach. The time of 3D lower limb model construction using AI was 4.7 min. AI-based 3D models can be used for surgical planning. CONCLUSION: AI was used for the first time to guide the 3D reconstruction of CT data of lower limbs for facilitating robotic-assisted TKA. Incorporation of AI in 3D model reconstruction before TKA might reduce the workload of radiologists.


Assuntos
Artroplastia do Joelho , Aprendizado Profundo , Prótese do Joelho , Procedimentos Cirúrgicos Robóticos , Inteligência Artificial , Humanos , Articulação do Joelho/cirurgia , Extremidade Inferior/diagnóstico por imagem , Extremidade Inferior/cirurgia , Tomografia Computadorizada por Raios X
14.
Int J Med Robot ; 17(4): e2264, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33855810

RESUMO

BACKGROUND: We investigated the accuracy and safety of a new HURWA robotic-assisted total knee arthroplasty (TKA) system in a sheep model. METHODS: Ten male small-tailed Han sheep were used in this study. Sheep were imaged by computed tomography scan before and after bone resection and the cutting errors between actual bone preparation and preoperative planning of the femur and tibia in three dimensions were measured. RESULTS: The overall accuracies after surgery compared with that from preoperative surgical planning of the left and right femurs were 1.93 ± 1.02° and 1.93 ± 1.23°, respectively. Additionally, similarly high overall accuracies for the left and right tibia of 1.26 ± 1.04 and 1.68 ± 0.92°, respectively, were obtained. The gap distances of the distal cut, anterior chamfer, anterior cut, posterior chamfer and posterior cut on the medial side were 0.47 ± 0.35 mm, 0.41 ± 0.37 mm, 0.12 ± 0.26 mm, 0.41 ± 0.44 mm and 0.12 ± 0.23 mm, respectively. No intraoperative complications, such as intraoperative fracture, massive bleeding or death, occurred. CONCLUSION: This new HURWA robotic-assisted TKA system is an accurate and safe tool for TKA surgery based on the sheep model.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Procedimentos Cirúrgicos Robóticos , Animais , Fêmur/cirurgia , Humanos , Articulação do Joelho/cirurgia , Masculino , Ovinos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia
15.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33783485

RESUMO

Tumor suppressor genes (TSGs) exhibit distinct evolutionary features. We speculated that TSG promoters could have evolved specific features that facilitate their tumor-suppressing functions. We found that the promoter CpG dinucleotide frequencies of TSGs are significantly higher than that of non-cancer genes across vertebrate genomes, and positively correlated with gene expression across tissue types. The promoter CpG dinucleotide frequencies of all genes gradually increase with gene age, for which young TSGs have been subject to a stronger evolutionary pressure. Transcription-related features, namely chromatin accessibility, methylation and ZNF263-, SP1-, E2F4- and SP2-binding elements, are associated with gene expression. Moreover, higher promoter CpG dinucleotide frequencies and chromatin accessibility are positively associated with the ability of TSGs to resist downregulation during tumorigenesis. These results were successfully validated with independent datasets. In conclusion, TSGs evolved specific promoter features that optimized cancer resistance through achieving high expression in normal tissues and resistance to downregulation during tumorigenesis.


Assuntos
Cromatina/metabolismo , Biologia Computacional/métodos , Resistencia a Medicamentos Antineoplásicos/genética , Evolução Molecular , Genes Supressores de Tumor , Neoplasias/genética , Regiões Promotoras Genéticas , Antineoplásicos/uso terapêutico , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Cromatina/ultraestrutura , Ilhas de CpG , Metilação de DNA , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Humanos , Anotação de Sequência Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Domínios e Motivos de Interação entre Proteínas , Transcrição Gênica
16.
Oncogene ; 40(9): 1578-1594, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33452458

RESUMO

Aberrant Notch activation has been implicated in multiple malignancies and the identification of NOTCH receptors and related pathways is critical for targeted therapy. In this study, we aim to delineate the most prominent dysregulated NOTCH receptor and comprehensively reveal its deregulation in gastric cancer (GC). In the four Notch members, NOTCH3 was found uniformly upregulated and associated with poor clinical outcomes in multiple GC datasets. siRNA-mediated NOTCH3 knockdown demonstrated antitumor effects by suppressing cell proliferation, inhibiting monolayer formation, and impairing cell invasion abilities. Its depletion also induced early and late apoptosis. NOTCH3 was confirmed to be a direct target of two tumor suppressor microRNAs (miRNAs), namely miR-491-5p and miR-875-5p. The activation of NOTCH3 is partly due to the silence of these two miRNAs. Through RNA-seq profiling and functional validation, PHLDB2 was identified as a potent functional downstream modulator for NOTCH3 in gastric carcinogenesis. PHLDB2 expression demonstrated a positive correlation with NOTCH3, but was negatively correlated with miR-491-5p. Akt-mTOR was revealed as the downstream signaling of PHLDB2. The NOTCH3-PHLDB2-Akt co-activation was found in 33.7% GC patients and the activation of this axis predicted poor clinical outcome. GC cells treated with siNOTCH3, siPHLDB2, miR-491-5p, miR-875-5p, were more sensitive to Cisplatin and 5-FU. Taken together, the NOTCH3-PHLDB2-Akt cascade plays oncogenic role in gastric carcinogenesis and serves as a therapeutic target. Our study provided insights into Notch-mediated underlying molecular mechanisms and implied translational potential.


Assuntos
Proteínas de Transporte/genética , MicroRNAs/genética , Receptor Notch3/genética , Neoplasias Gástricas/genética , Apoptose/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Oncogênica v-akt/genética , RNA Interferente Pequeno/genética , Neoplasias Gástricas/patologia , Serina-Treonina Quinases TOR/genética
17.
Cell Prolif ; 54(1): e12936, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33103338

RESUMO

Osteosarcoma is the most common primary bone malignancy and is a neoplasm thought to be derived from the bone-forming mesenchymal stem cells. Aberrant activation of oncogenes and inactivation of tumour suppressor genes by somatic mutations and epigenetic mechanisms play a pivotal pathogenic role in osteosarcoma. Aside from alterations in these protein-coding genes, it has now been realized that dysregulation of non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and the recently discovered circular RNAs (circRNAs), is crucial to the initiation and progression of osteosarcoma. CircRNAs are single-stranded RNAs that form covalently closed loops and function as an important regulatory element of the genome through multiple machineries. Recently, an increasing number of studies suggested that circRNAs also played critical roles in osteosarcoma. This review summarizes recent development and progression in circRNA transcriptome analysis and their functions in the modulation of osteosarcoma progression.


Assuntos
Osteossarcoma/genética , Osteossarcoma/metabolismo , RNA Circular/metabolismo , Humanos , Osteossarcoma/patologia , RNA Circular/genética
18.
Cancers (Basel) ; 12(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218162

RESUMO

The role of oral microbiota in head and neck squamous cell carcinoma (HNSCC) is poorly understood. Here we sought to evaluate the association of the bacterial microbiome with host gene methylation and patient outcomes, and to explore its potential as a biomarker for early detection or intervention. Here we performed 16S rRNA gene amplicon sequencing in sixty-eight HNSCC patients across both tissue and oral rinse samples to identify oral bacteria with differential abundance between HNSCC and controls. A subset of thirty-one pairs of HNSCC tumor tissues and the adjacent normal tissues were characterized for host gene methylation profile using bisulfite capture sequencing. We observed significant enrichments of Fusobacterium and Peptostreptococcus in HNSCC tumor tissues when compared to the adjacent normal tissues, and in HNSCC oral rinses when compared to healthy subjects, while ten other bacterial genera were largely depleted. These HNSCC-related bacteria were discriminative for HNSCC and controls with area under the receiver operating curves (AUCs) of 0.84 and 0.86 in tissue and oral rinse samples, respectively. Moreover, Fusobacterium nucleatum abundance in HNSCC cases was strongly associated with non-smokers, lower tumor stage, lower rate of recurrence, and improved disease-specific survival. An integrative analysis identified that enrichment of F. nucleatum was associated with host gene promoter methylation, including hypermethylation of tumor suppressor genes LXN and SMARCA2, for which gene expressions were downregulated in the HNSCC cohort from The Cancer Genome Atlas. In conclusion, we identified a taxonomically defined microbial consortium associated with HNSCC that may have clinical potential regarding biomarkers for early detection or intervention. Host-microbe interactions between F. nucleatum enrichment and clinical outcomes or host gene methylation imply a potential role of F. nucleatum as a pro-inflammatory driver in initiating HNSCC without traditional risk factors, which warrants further investigation for the underlying mechanisms.

19.
Oncogene ; 39(43): 6647-6663, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32934314

RESUMO

Fibroblast growth factor receptor type 2 (FGFR2) has emerged as a key oncogenic factor that regulates gastric cancer (GC) progression, but the underlying mechanism of FGF-FGFR2 signaling pathway remains largely unknown. To identify the potential molecular mechanisms of the oncogenic FGFR2 in gastric carcinogenesis and convey a novel therapeutic strategy, we profiled the FGFR alterations and analyzed their clinical associations in TCGA and Hong Kong GC cohorts. We found that FGFR2 overexpression in GC cell lines and primary tumors predicted poor survival and was associated with advanced stages of GC. Functionally, growth abilities and cell cycle progression of GC were inhibited by inactivation of ERK-MAPK signal transduction after FGFR2 knockdown, while apoptosis was promoted. Meanwhile, the first-line anti-cancer drug sensitivity was enhanced. RNA-seq analysis further revealed that YAP1 signaling serves as a significant downstream modulator and mediates the oncogenic signaling of FGFR2. When stimulating FGFR2 by rhFGF18, we observed intensified F-actin, nuclear accumulation of YAP1, and overexpression of YAP1 targets, but these effects were attenuated by either FGFR2 depletion or AZD4547 administration. Additionally, the FGF18-FGFR2 signaling upregulated YAP1 expression through activating c-Jun, an effector of MAPK signaling. In our cohort, 28.94% of GC cases were characterized as FGFR2, c-Jun, and YAP1 co-positive and demonstrated worse clinical outcomes. Remarkably, we also found that co-targeting FGFR2 and YAP1 by AZD4547 and Verteporfin synergistically enhanced the antitumor effects in vitro and in vivo. In conclusion, we have identified the oncogenic FGF-FGFR2 regulates YAP1 signaling in GC. The findings also highlight the translational potential of FGFR2-c-Jun-YAP1 axis, which may serve as a prognostic biomarker and therapeutic target for GC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Fatores de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Neoplasias Gástricas/patologia , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Linhagem Celular Tumoral , Estudos de Coortes , Variações do Número de Cópias de DNA , Conjuntos de Dados como Assunto , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Estimativa de Kaplan-Meier , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Prognóstico , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas c-jun/metabolismo , Pirazóis/farmacologia , Pirazóis/uso terapêutico , RNA-Seq , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidade , Fatores de Transcrição/antagonistas & inibidores , Regulação para Cima , Verteporfina/farmacologia , Verteporfina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Sinalização YAP
20.
Environ Sci Pollut Res Int ; 27(26): 32467-32473, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556990

RESUMO

Emerging evidence suggested that long non-coding RNAs (lncRNAs) play pivotal roles in tumorigenesis. LINC01133 is a newly identified lncRNA first discovered as an oncogene in lung squamous cell carcinoma. Subsequent studies further demonstrated this lncRNA was deregulated in a wide spectrum of tumors, including colorectal, gastric, lung, and pancreatic ductal adenocarcinoma as well as osteosarcoma and hepatocellular carcinoma. Intriguingly, this lncRNA exerted oncogenic or tumor-suppressive action in a tissue-dependent manner. This review sought to summarize our current understanding concerning the deregulation of LINC01133 in human tumors in relation to its molecular mechanisms and cellular functions. The clinical utilization of LINC01133 as a potential prognostic biomarker and a treatment target is also discussed.


Assuntos
Neoplasias Ósseas , Neoplasias Pulmonares/genética , Osteossarcoma , RNA Longo não Codificante , Regulação Neoplásica da Expressão Gênica , Humanos
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