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1.
Small ; : e2310851, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334256

RESUMO

Inspired by the timely emergence of silkworm pupae from their cocoons, silkworm chrysalis-like probiotic composites (SCPCs) are developed for the comprehensive therapy of inflammatory bowel disease (IBD), in which probiotics are enveloped as the "pupa" in a sequential layering of silk sericin (SS), tannic acid (TA), and polydopamine, akin to the protective "cocoon". Compared to unwrapped probiotics, these composites not only demonstrate exceptional resistance to the harsh gastrointestinal environment and exhibit over 200 times greater intestinal colonization but also safeguard probiotics from the damage of IBD environment while enabling probiotics sustained release. The probiotics, in synergy with SS and TA, provide a multi-crossed comprehensive therapy for IBD that simultaneously addresses various pathological features of IBD, including intestinal barrier disruption, elevated pro-inflammatory cytokines, heightened oxidative stress, and disturbances in the intestinal microbiota. SCPCs exhibit remarkable outcomes, including a 9.7-fold reduction in intestinal permeability, an 8.9-fold decrease in IL-6 levels, and a 2.9-fold reduction in TNF-α levels compared to uncoated probiotics. Furthermore, SCPCs demonstrate an impressive 92.25% reactive oxygen species clearance rate, significantly enhance the richness of beneficial intestinal probiotics, and effectively diminish the abundance of pathogenic bacteria, indicating a substantial improvement in the overall therapeutic effect of IBD.

2.
Surg Endosc ; 38(4): 1912-1921, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38326587

RESUMO

BACKGROUND: Many patients experience anorectal dysfunction after rectal surgery, which is known as low anterior resection syndrome (LARS). Robotic systems have many technical advantages that may be suitable for functional preservation after low rectal resection. Thus, the study aimed to explore whether robotic surgery can reduce the incidence and severity of LARS. METHODS: Patients undergoing minimally invasive sphincter-sparing surgery for low rectal cancer were enrolled between January 2015 and December 2020. The patients were divided into robotic or laparoscopic groups. The LARS survey was conducted at 6, 12 and 18 months postoperatively. Major LARS scores were analysed as the primary endpoint. In order to reduce confounding factors, one-to-two propensity score matches were used. RESULTS: In total, 342 patients were enrolled in the study. At 18 months postoperatively, the incidence of LARS was 68.7% (235/342); minor LARS was identified in 112/342 patients (32.7%), and major LARS in 123/342 (36.0%). After matching, the robotic group included 74 patients, and the laparoscopic group included 148 patients. The incidence of major LARS in the robotic group was significantly lower than that in the laparoscopic group at 6, 12, and 18 months after surgery. In multivariate logistic regression analysis, tumour location, laparoscopic surgery, intersphincteric resection, neoadjuvant therapy, and anastomotic leakage were independent risk factors for major LARS after minimally invasive sphincter-sparing surgery for low rectal cancer. Furthermore, a major LARS prediction model was constructed. Results of model evaluation showed that the nomogram had good prediction accuracy and efficiency. CONCLUSIONS: Patients with low rectal cancer may benefit from robotic surgery to reduce the incidence and severity of LARS. Our nomogram could aid surgeons in setting an individualized treatment program for low rectal cancer patients.


Assuntos
Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Síndrome de Ressecção Anterior Baixa , Canal Anal/cirurgia , Canal Anal/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Pontuação de Propensão , Tratamentos com Preservação do Órgão
3.
J Biochem Mol Toxicol ; 38(2): e23647, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348718

RESUMO

Hepatocellular carcinoma (HCC) is among the world's worst malignancies. Nuclear division cycle 1 (NDC1) is an essential membrane-integral nucleoporin, found in this study to be significantly increased in primary HCC. A multivariate analysis revealed that higher NDC1 expression was linked to worse outcome in HCC patients. Mouse xenograft tumors overexpressing NDC1 grew rapidly, and HCC cells overexpressing NDC1 showed enhanced proliferation, invasion, and migration in vitro. In contrast, knocking down NDC1 had the opposite effects in vitro. Furthermore, co-immunoprecipitation and liquid chromatograph mass spectrometer analyses revealed that NDC1 activated PI3K/AKT signaling by interacting with BCAP31. In summary, NDC1 and BCAP31 cooperate to promote the PI3K/AKT pathway, which is essential for HCC carcinogenesis. This suggests that NDC1 is predictive of prognosis in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinogênese , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Divisão do Núcleo Celular , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
4.
Br J Surg ; 111(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38215239

RESUMO

BACKGROUND: The aim of this multicentre cohort study was to compare the long-term oncological outcomes of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for patients with gastric cancer. METHODS: Patients with gastric cancer who underwent radical gastrectomy by robotic or laparoscopic approaches from 1 March 2010 to 31 December 2018 at 10 high-volume centres in China were selected from institutional databases. Patients receiving RG were matched 1 : 1 by propensity score with patients undergoing LG. The primary outcome was 3-year disease-free survival. Secondary outcomes were overall survival and disease recurrence. RESULTS: Some 2055 patients who underwent RG and 4309 patients who had LG were included. The propensity score-matched cohort comprised 2026 RGs and 2026 LGs. Median follow-up was 41 (i.q.r. 39-58) months for the RG group and 39 (38-56) months for the LG group. The 3-year disease-free survival rates were 80.8% in the RG group and 79.5% in the LG group (log rank P = 0.240; HR 0.92, 95% c.i. 0.80 to 1.06; P = 0.242). Three-year OS rates were 83.9 and 81.8% respectively (log rank P = 0.068; HR 0.87, 0.75 to 1.01; P = 0.068) and the cumulative incidence of recurrence over 3 years was 19.3% versus 20.8% (HR 0.95, 0.88 to 1.03; P = 0.219), with no difference between groups. CONCLUSION: RG and LG in patients with gastric cancer are associated with comparable disease-free and overall survival.


Assuntos
Laparoscopia , Levamisol/análogos & derivados , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Resultado do Tratamento , Estudos de Coortes , Neoplasias Gástricas/cirurgia , Gastrectomia , Pontuação de Propensão , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia
5.
Ann Surg ; 279(5): 808-817, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38264902

RESUMO

OBJECTIVE: To compare the short-term and long-term outcomes between robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for gastric cancer. BACKGROUND: The clinical outcomes of RG over LG have not yet been effectively demonstrated. METHODS: This retrospective cohort study included 3599 patients with gastric cancer who underwent radical gastrectomy at eight high-volume hospitals in China from January 2015 to June 2019. Propensity score matching was performed between patients who received RG and LG. The primary end point was 3-year disease-free survival (DFS). RESULTS: After 1:1 propensity score matching, 1034 pairs of patients were enrolled in a balanced cohort for further analysis. The 3-year DFS in the RG and LG was 83.7% and 83.1% ( P =0.745), respectively, and the 3-year overall survival was 85.2% and 84.4%, respectively ( P =0.647). During 3 years of follow-up, 154 patients in the RG and LG groups relapsed (cumulative incidence of recurrence: 15.0% vs 15.0%, P =0.988). There was no significant difference in the recurrence sites between the 2 groups (all P >0.05). Sensitivity analysis showed that RG had comparable 3-year DFS (77.4% vs 76.7%, P =0.745) and overall survival (79.7% vs 78.4%, P =0.577) to LG in patients with advanced (pathologic T2-4a) disease, and the recurrence pattern within 3 years was also similar between the 2 groups (all P >0.05). RG had less intraoperative blood loss, lower conversion rate, and shorter hospital stays than LG (all P >0.05). CONCLUSIONS: For resectable gastric cancer, including advanced cases, RG is a safe approach with comparable 3-year oncological outcomes to LG when performed by experienced surgeons.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Resultado do Tratamento , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Gastrectomia , Pontuação de Propensão , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia
6.
Nat Commun ; 15(1): 427, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38199995

RESUMO

The microbiome in a specific human organ has been well-studied, but few reports have investigated the multi-organ microbiome as a whole. Here, we aim to analyse the intra-individual inter-organ and intra-organ microbiome in deceased humans. We collected 1608 samples from 53 sites of 7 surface organs (oral cavity, esophagus, stomach, small intestine, appendix, large intestine and skin; n = 33 subjects) and performed microbiome profiling, including 16S full-length sequencing. Microbial diversity varied dramatically among organs, and core microbial species co-existed in different intra-individual organs. We deciphered microbial changes across distinct intra-organ sites, and identified signature microbes, their functional traits, and interactions specific to each site. We revealed significant microbial heterogeneity between paired mucosa-lumen samples of stomach, small intestine, and large intestine. Finally, we established the landscape of inter-organ relationships of microbes along the digestive tract. Therefore, we generate a catalogue of bacterial composition, diversity, interaction, functional traits, and bacterial translocation in human at inter-organ and intra-organ levels.


Assuntos
Apêndice , Microbiota , Humanos , Translocação Bacteriana , Estômago , Microbiota/genética , Boca
7.
J Transl Med ; 22(1): 30, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184566

RESUMO

BACKGROUND: Colorectal cancer (CRC) has been the third most prevalent cancer worldwide. Liver metastasis is the critical factor for the poor prognosis of CRC. Here, we investigated the expression and role of PLOD3 in CRC. METHODS: Different liver metastasis models were established by injecting PLOD3 stable knockdown or overexpression CT26 or MC38 mouse CRC cells into the spleen of mice to verify the tumorigenicity and metastasis ability in vivo. RESULTS: We identified PLOD3 is significantly overexpressed in liver metastasis samples of CRC. High expression of PLOD3 was significantly associated with poor survival of CRC patients. The knockdown of PLOD3 exhibited remarkable inhibition of proliferation, migration, and invasion in CRC cells, while the opposite results could be found in different PLOD3-overexpressed CRC cells. Stable knockdown of PLOD3 also significantly inhibited liver metastasis of CRC cells in different xenografts models, while stable overexpression of PLOD3 promotes liver metastasis and tumor progression. Further studies showed that PLOD3 facilitated the T cell activation in the tumor microenvironment and affected the TNF-α/ NF-κB pathway. CONCLUSIONS: This study revealed the essential biological functions of PLOD3 in colon cancer progression and metastasis, suggesting that PLOD3 is a promising translational medicine target and bioengineering targeting PLOD3 overcomes CRC liver metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Neoplasias Colorretais/genética , Neoplasias Hepáticas/genética , NF-kappa B , Linfócitos T , Microambiente Tumoral , Fator de Necrose Tumoral alfa
8.
Sci Rep ; 14(1): 2180, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273073

RESUMO

Tumor budding is a long-established independent adverse prognostic marker for colorectal cancer (CRC), yet assessment of tumor budding was not reproducible. Therefore, development of precise diagnostic approaches to tumor budding is in demand. In this study, we first performed bioinformatic analysis in our single-center CRC patients' cohort (n = 84) and identified tumor budding-associated hub genes using the weighted gene co-expression network analysis (WGCNA). A machine learning methodology was used to identify hub genes and construct a prognostic signature. Nomogram model was used to identified hub genes score for tumor budding, and the receiver operating characteristic (ROC) curve and calibration plot indicated high accuracy and stability of hub gene score for predicted the prognosis of CRC. The association between budding-associated hub genes and score and prognosis of CRC were further verified in TCGA CRC cohort (n = 342). Then gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were applied to explore the signaling pathways related to the tumor budding and validated by immunohistochemistry (IHC) of our clinical samples. Subsequently, immune infiltration analysis demonstrated that there was a high correlation between hub genes score and M2-like macrophages infiltrated in tumor tissue. In addition, somatic mutation and chemotherapeutic response prediction were analyzed based on the risk signature. In summary, we established a tumor budding diagnostic molecular model, which can improve tumor budding assessment and provides a promising novel molecular marker for immunotherapy and prognosis of CRC.


Assuntos
Neoplasias Colorretais , Imunoterapia , Humanos , Prognóstico , Nomogramas , Calibragem , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia
9.
Surg Today ; 54(3): 220-230, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37468743

RESUMO

PURPOSE: Robotic lateral lymph node dissection (LLND) has been described as a safe and feasible procedure for local advanced rectal cancer. The aim of this study was to evaluate the learning curve for robotic-assisted LLND. METHODS: We collected data on 78 consecutive patients who underwent robotic-LLND at our hospital. The learning curve was analyzed using the cumulative sum (CUSUM) method to assess changes in the unilateral LLND operative times across the case sequence. RESULTS: Among the 78 patients, 52 underwent bilateral LLND and 26 underwent unilateral LLND. A total of 130 consecutive data were recorded. We arranged unilateral robotic-LLND operative times and calculated cumulative sum values, allowing the differentiation of three phases: phase I (learning period, cases 1-51); phase II (proficiency period, cases 52-83); and phase III (mastery period, cases 84-130). As the learning curve accumulated, the operation time and estimated blood loss of unilateral robotic-LLND decreased significantly with each phase (P < 0.05). By 12 months after surgery, the International Prostatic Symptom Score of patients at phase III was significantly lower than at phase I (P < 0.05). CONCLUSION: The CUSUM curve shows three phases in the learning of robotic-LLND. The estimated learning curve for robotic-assisted rectal-LLND is achieved after 51 cases.


Assuntos
Laparoscopia , Neoplasias Retais , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Excisão de Linfonodo/métodos , Reto/cirurgia , Linfonodos/patologia , Curva de Aprendizado , Estudos Retrospectivos , Recidiva Local de Neoplasia/cirurgia
10.
Nucleic Acids Res ; 51(22): 12140-12149, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37904586

RESUMO

Gut phages have an important impact on human health. Methylation plays key roles in DNA recognition, gene expression regulation and replication for phages. However, the DNA methylation landscape of gut phages is largely unknown. Here, with PacBio sequencing (2120×, 4785 Gb), we detected gut phage methylation landscape based on 22 673 gut phage genomes, and presented diverse methylation motifs and methylation differences in genomic elements. Moreover, the methylation rate of phages was associated with taxonomy and host, and N6-methyladenine methylation rate was higher in temperate phages than in virulent phages, suggesting an important role for methylation in phage-host interaction. In particular, 3543 (15.63%) phage genomes contained restriction-modification system, which could aid in evading clearance by the host. This study revealed the DNA methylation landscape of gut phage and its potential roles, which will advance the understanding of gut phage survival and human health.


Assuntos
Bacteriófagos , Metilação de DNA , Microbioma Gastrointestinal , Humanos , Bacteriófagos/fisiologia , Bactérias/virologia , Archaea/virologia , Enzimas de Restrição-Modificação do DNA
11.
Front Nutr ; 10: 1237047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37671200

RESUMO

Objective: The assessment of nutritional status has been recognized as crucial in the treatment of geriatric cancer patients. The objective of this study is to determine the clinical predictive value of the geriatric nutritional risk index (GNRI) in predicting the short-term and long-term prognosis of elderly rectal cancer (RC) patients who undergo surgical treatment after neoadjuvant therapy. Methods: Between January 2014 and December 2020, the clinical materials of 639 RC patients aged ≥70 years who underwent surgical treatment after neoadjuvant therapy were retrospectively analysed. Propensity score matching was performed to adjust for baseline potential confounders. Logistic regression analysis and competing risk analysis were conducted to evaluate the correlation between the GNRI and the risk of postoperative major complications and cumulative incidence of cancer-specific survival (CSS). Nomograms were then constructed for postoperative major complications and CSS. Additionally, 203 elderly RC patients were enrolled between January 2021 and December 2022 as an external validation cohort. Results: Multivariate logistic regression analysis showed that GNRI [odds ratio = 1.903, 95% confidence intervals (CI): 1.120-3.233, p = 0.017] was an independent risk factor for postoperative major complications. In competing risk analysis, the GNRI was also identified as an independent prognostic factor for CSS (subdistribution hazard ratio = 3.90, 95% CI: 2.46-6.19, p < 0.001). The postoperative major complication nomogram showed excellent performance internally and externally in the area under the receiver operating characteristic curve (AUC), calibration plots and decision curve analysis (DCA). When compared with other models, the competing risk prognosis nomogram incorporating the GNRI achieved the highest outcomes in terms of the C-index, AUC, calibration plots, and DCA. Conclusion: The GNRI is a simple and effective tool for predicting the risk of postoperative major complications and the long-term prognosis of elderly RC patients who undergo surgical treatment after neoadjuvant therapy.

12.
Sci Rep ; 13(1): 14866, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684265

RESUMO

Treatment guidelines for colorectal cancer (CRC) in elderly patients remain unclear. This study aimed to investigate whether elderly patients (≥ 70 years) with CRC benefit from surgery and adjuvant therapy. A total of 90,347 eligible CRC patients older than 70 years were collected from the Surveillance, Epidemiology, and End Results (SEER) database and divided into a surgery group and a no-surgery group. After being matched by propensity score matching at a 1:1 ratio, 23,930 patients were included in our analysis. The Kaplan‒Meier method and log-rank test were applied to compare overall survival (OS) and cancer-specific survival (CSS). Univariate and multivariate Cox regression analyses were utilized to confirm independent prognostic factors for OS and CSS. In age-stratified analysis (70-74; 75-79; 80-84; ≥ 85), the OS and CSS rates of patients in the surgery group were significantly higher than those of patients in the no-surgery group (all P < 0.001). Adjuvant therapy was an independent prognostic factor for OS and CSS in elderly patients with CRC (all P < 0.001). Further analysis showed that elderly colon cancer patients with stage III and stage IV disease gained a survival benefit from adjuvant chemotherapy. Adjuvant chemoradiotherapy can significantly improve OS and CSS in elderly rectal cancer patients with stage II, III, and IV disease. In conclusion, among CRC patients aged ≥ 70 years reported in the SEER database, treatment with surgical resection is significantly associated with improved OS and CSS. Moreover, adjuvant therapy led to a significant prognostic advantage for elderly advanced CRC patients who underwent surgery.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Idoso , Humanos , Terapia Combinada , Quimioterapia Adjuvante , Quimiorradioterapia Adjuvante , Neoplasias Colorretais/cirurgia
13.
bioRxiv ; 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37745439

RESUMO

While cell fate determination and maintenance are important in establishing and preserving tissue identity and function during development, aberrant cell fate transition leads to cancer cell heterogeneity and resistance to treatment. Here, we report an unexpected role for the transcription factor p63 (Trp63/TP63) in the fate choice of squamous versus neuroendocrine lineage in esophageal development and malignancy. Deletion of p63 results in extensive neuroendocrine differentiation in the developing mouse esophagus and esophageal progenitors derived from human embryonic stem cells. In human esophageal neuroendocrine carcinoma (eNEC) cells, p63 is transcriptionally silenced by EZH2-mediated H3K27 trimethylation (H3K27me3). Upregulation of the major p63 isoform ΔNp63α, through either ectopic expression or EZH2 inhibition, promotes squamous transdifferentiation of eNEC cells. Together these findings uncover p63 as a rheostat in coordinating the transition between squamous and neuroendocrine cell fates during esophageal development and tumor progression.

14.
Front Immunol ; 14: 1228581, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529049

RESUMO

Background: PD-1/PD-L1 immune checkpoint inhibitors are currently the most commonly utilized agents in clinical practice, which elicit an immunostimulatory response to combat malignancies. However, all these inhibitors are currently administered via injection using antibody-based therapies, while there is a growing need for oral alternatives. Methods: This study has developed and synthesized exosome-wrapped gold-peptide nanocomplexes with low immunogenicity, which can target PD-L1 and activate antitumor immunity in vivo through oral absorption. The SuperPDL1exo was characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel silver staining. The transmembrane ability of SuperPDL1exo was evaluated by flow cytometry and immunofluorescence. Cell viability was determined using the Cell Counting Kit-8 (CCK-8) assay. ELISA experiments were conducted to detect serum and tissue inflammatory factors, as well as serum biochemical indicators. Tissue sections were stained with H&E for the evaluation of the safety of SuperPDL1exo. An MC38 colon cancer model was established in immunocompetent C56BL/6 mice to evaluate the effects of SuperPDL1exo on tumor growth in vivo. Immunohistochemistry (IHC) staining was performed to detect cytotoxicity factors such as perforin and granzymes. Results: First, SuperPDL1 was successfully synthesized, and milk exosome membranes were encapsulated through ultrasound, repeated freeze-thaw cycles, and extrusion, resulting in the synthesis of SuperPDL1exo. Multiple characterization results confirmed the successful synthesis of SuperPDL1exo nanoparticles. Furthermore, our data demonstrated that SuperPDL1exo exhibited excellent colloidal stability and superior cell transmembrane ability. In vitro and in vivo experiments revealed that SuperPDL1exo did not cause damage to multiple systemic organs, demonstrating its good biocompatibility. Finally, in the MC38 colon cancer mouse model, it was discovered that SuperPDL1exo could inhibit the progression of colon cancer, and this tumor-suppressive effect was mediated through the activation of tumor-specific cytotoxic T lymphocyte (CTL)-related immune responses. Conclusion: This study has successfully designed and synthesized an oral nanotherapeutic, SuperPDL1exo, which demonstrates small particle size, excellent colloidal stability, transmembrane ability in tumor cells, and biocompatibility. In vivo experiments have shown that it effectively activates T-cell immunity and exerts antitumor effects.


Assuntos
Neoplasias do Colo , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Receptor de Morte Celular Programada 1/metabolismo , Linhagem Celular Tumoral , Antígeno B7-H1/metabolismo , Imunoterapia/métodos , Peptídeos
15.
Cell Rep ; 42(7): 112781, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37421630

RESUMO

Type VI secretion system is widely used in Gram-negative bacteria for injecting toxic effectors into neighboring prokaryotic or eukaryotic cells. Various effectors can be loaded onto the T6SS delivery tube via its core components: Hcp, VgrG, or PAAR. Here, we report 2.8-Å resolution cryo-EM structure of intact T6SS Hcp5-VgrG-PAAR cargo delivery system and crystal structure of unbound Hcp5 from B. fragilis NCTC 9343. Loading of Hcp5 hexameric ring onto VgrG causes expansion of its inner cavity and external surface, explaining how structural changes could be propagated to regulate co-polymerization and surrounding contractile sheath. High-affinity binding between Hcp and VgrG causes entropically unfavorable structuring of long loops. Furthermore, interactions between VgrG trimer and Hcp hexamer are asymmetric, with three of the six Hcp monomers exhibiting a major loop flip. Our study provides insights into the assembly, loading, and firing of T6SS nanomachine that contributes to bacterial inter-species competition and host interactions.


Assuntos
Sistemas de Secreção Tipo VI , Sistemas de Secreção Tipo VI/metabolismo , Proteínas de Bactérias/metabolismo
16.
Structure ; 31(8): 935-947.e4, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37329879

RESUMO

PaaY is a thioesterase that enables toxic metabolites to be degraded through the bacterial phenylacetic acid (PA) pathway. The Acinetobacter baumannii gene FQU82_01591 encodes PaaY, which we demonstrate to possess γ-carbonic anhydrase activity in addition to thioesterase activity. The crystal structure of AbPaaY in complex with bicarbonate reveals a homotrimer with a canonical γ-carbonic anhydrase active site. Thioesterase activity assays demonstrate a preference for lauroyl-CoA as a substrate. The AbPaaY trimer structure shows a unique domain-swapped C-termini, which increases the stability of the enzyme in vitro and decreases its susceptibility to proteolysis in vivo. The domain-swapped C-termini impact thioesterase substrate specificity and enzyme efficacy without affecting carbonic anhydrase activity. AbPaaY knockout reduced the growth of Acinetobacter in media containing PA, decreased biofilm formation, and impaired hydrogen peroxide resistance. Collectively, AbPaaY is a bifunctional enzyme that plays a key role in the metabolism, growth, and stress response mechanisms of A. baumannii.


Assuntos
Acinetobacter baumannii , Anidrases Carbônicas , Acinetobacter baumannii/genética , Anidrases Carbônicas/genética , Biofilmes , Antibacterianos/química
17.
Heliyon ; 9(3): e13904, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36873554

RESUMO

Sciatic hernia is one of the rarely pelvic floor hernias. We report a 45-year-old woman who presented with acute crampy pain of hypogastrium which radiated down the back of the left thigh and found a mass in her left buttock area which is about fist size with local pain, so she had to force to bow position when walking. She was also associated with definite gastro-intestinal symptoms. Computed tomography (CT) of the pelvis and abdomen demonstrated the herniation of an ileal loop through the sciatic foramen on the left side. The diagnosis and management of this case are herein described and previous publications on sciatic hernias are reviewed.

18.
Biomedicines ; 11(3)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36979860

RESUMO

Barrett's esophagus (BE) is a precancerous lesion of esophageal adenocarcinoma (EAC). It is a pathological change in which the squamous epithelium distal esophagus is replaced by columnar epithelium. Loss of P53 is involved in the development of BE and is taken as a risk factor for the progression. We established a HET1A cell line with P53 stably knockdown by adenovirus vector infection, followed by 30 days of successive acidic bile salt treatment. MTT, transwell assay, and wound closure assay were applied to assess cell proliferation and migration ability. The expression of key factors was analyzed by RT-qPCR, western blotting and immunohistochemical staining. Our data show that the protein expression level of P53 reduced after exposure to acidic bile salt treatment, and the P53 deficiency favors the survival of esophageal epithelial cells to accommodate the stimulation of acidic bile salts. Furthermore, exposure to acidic bile salt decreases cell adhesions by repressing the JAK/STAT signaling pathway and activating VEGFR/AKT in P53-deficient esophageal cells. In EAC clinical samples, P53 protein expression is positively correlated with that of ICAM1 and STAT3 and negatively correlated with VEGFR protein expression levels. These findings elucidate the role of P53 in the formation of BE, explain the mechanism of P53 deficiency as a higher risk of progression for BE formation, and provide potential therapeutic targets for EAC.

19.
Oncogene ; 42(13): 941-951, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859558

RESUMO

Extrachromosomal circular DNA (ecDNA) has gained renewed interest since its discovery more than half a century ago, emerging as critical driver of tumor evolution. ecDNA is highly prevalent in many types of cancers, including colorectal cancer (CRC), which is one of the most deadly cancers worldwide. ecDNAs play an essential role in regulating oncogene expression, intratumor heterogeneity, and resistance to therapy independently of canonical chromosomal alterations in CRC. Furthermore, the existence of ecDNAs is attributed to the patient's prognosis, since ecDNA-based oncogene amplification adversely affects clinical outcomes. Recent understanding of ecDNA put an extra layer of complexity in the pathogenesis of CRC. In this review, we will discuss the current understanding on mechanisms of biogenesis, and distinctive features of ecDNA in CRC. In addition, we will examine how ecDNAs mediate oncogene overexpression, gene regulation, and topological interactions with active chromatin, which facilitates genetic heterogeneity, accelerates CRC malignancy, and enhances rapid adaptation to therapy resistance. Finally, we will discuss the potential diagnostic and therapeutic implications of ecDNAs in CRC.


Assuntos
Neoplasias Colorretais , Neoplasias , Humanos , DNA , Oncogenes , Neoplasias/genética , Cromatina , DNA Circular/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética
20.
Clin Res Hepatol Gastroenterol ; 47(3): 102090, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36746236

RESUMO

BACKGROUND AND AIMS: The appendix has an important immune function in both health and disease, and appendectomy may influence microbial ecology and immune function. This meta-analysis aims to assess the association between appendectomy and the risk and course of Crohn's disease (CD). METHODS: PubMed, EMBASE, and the Cochrane Library were used to identify all studies published until June 2022. Data from studies evaluating the association between appendectomy and CD were reviewed. RESULTS: A total of 28 studies were included in the final analysis, comprising 22 case-control and 6 cohort studies. A positive relationship between prior appendectomy and the risk of developing CD was observed in both case-control studies (odds ratio [OR]: 1.59, 95% confidence interval [CI]: 1.22-2.08) and cohort studies (relative risk [RR]: 2.28, 95% CI: 1.66-3.14). The elevated risk of CD persisted 5 years post-appendectomy (RR = 1.24, 95% CI: 1.12-1.36). The risk of developing CD was similarly elevated regardless of the presence (RR = 1.64, 95% CI: 1.17-2.31) or absence (RR = 2.77, 95% CI: 1.84-4.16) of appendicitis in patients. Moreover, significant differences were found in the proportion of terminal ileum lesions (OR = 1.63; 95% CI: 1.38-1.93) and colon lesions (OR = 0.70; 95% CI: 0.5-0.84) between CD patients with appendectomy and those without appendectomy. CONCLUSIONS: The risk of developing CD following an appendectomy is significant and persists 5 years postoperatively. Moreover, the elevated risk of CD may mainly occur in the terminal ileum.


Assuntos
Apêndice , Doença de Crohn , Humanos , Apendicectomia , Estudos de Coortes , Estudos de Casos e Controles
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