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1.
Biochem Genet ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38198021

RESUMO

Colorectal cancer (CRC) is a common human malignancy and the third leading cause of cancer-related death worldwide. Cancer stem cells (CSCs) were considered to play important roles in the genesis and development of many tumors. In recent years, it has been observed that leukemia inhibitory factor (LIF) might be involved in the regulation of stemness in cancer cells. In this study, we observed that LIF could increase the spheroid formation and stemness marker expression (inculding Nanog and SOX2) in CRC cell lines, such as HCT116 and Caco2 cells. Meanwhile, we also observed that LIF could upregulate LncRNA H19 expression via PI3K/AKT pathway. Knockdown of the expression of LncRNA H19 could decrease the spheroid formation and SOX2 expression in LIF-treated HCT116 and Caco2 cells, and thereby LncRNA H19 knockdown could compensate for the stemness enhancement effects induced by LIF. Our results indicated that LncRNA H19 might participate in the stemness promotion of LIF in CRC cells.

2.
bioRxiv ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38076896

RESUMO

Malignant peripheral nerve sheath tumor (MPNST) is a rare, aggressive soft-tissue sarcoma with a poor prognosis and is insensitive to immune checkpoint blockade (ICB) therapy. Loss-of-function of the histone modifying polycomb repressive complex 2 (PRC2) components, EED or SUZ12, is one of the main mechanisms of malignant transformation. In a murine model of MPNST, PRC2-loss tumors have an "immune desert" phenotype and intratumoral (IT) delivery immunogenic modified vaccinia virus Ankara (MVA) sensitized the PRC2-loss tumors to ICB. Here we show that IT MQ833, a second-generation recombinant modified vaccinia virus Ankara virus, results in neutrophil recruitment and activation and neutrophil-dependent tumor killing in the MPNST model. MQ833 was engineered by deleting three viral immune evasion genes, E5R, E3L, and WR199, and expressing three transgenes, including the two membrane-bound Flt3L and OX40L, and IL-12 with an extracellular matrix anchoring signal. Furthermore, we explored strategies to enhance anti-tumor effects of MQ833 by co-administration of granulocyte colony-stimulating factor (G-CSF).

3.
Environ Sci Pollut Res Int ; 30(55): 117637-117653, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37870669

RESUMO

The possibility of using the non-nitrogen-fixing cyanobacterium (Chroococcus sp.) for the reduction of soil nitrate contamination was tested through Petri dish experiments. The application of 0.03, 0.05 and 0.08 mg/cm2 Chroococcus sp. efficiently removed NO3--N from the soil through assimilation of nitrate nutrient and promotion of soil denitrification. At the optimal application dose of 0.05 mg/cm2, 44.06%, 36.89% and 36.17% of NO3--N were removed at initial NO3--N concentrations of 60, 90 and 120 mg/kg, respectively. The polysaccharides released by Chroococcus sp. acted as carbon sources for bacterial denitrification and facilitated the reduction of soil salinity, which significantly (p < 0.05) stimulated the growth of denitrifying bacteria (Hyphomicrobium denitrificans and Hyphomicrobium sp.) as well as significantly (p < 0.05) elevated the activities of nitrate reductase and nitrite reductase by 1.07-1.23 and 1.15-1.22 times, respectively. The application of Chroococcus sp. promoted the dominance of Nocardioides maradonensis in soil microbial community, which resulted in elevated phosphatase activity and increased available phosphorus content. The application of Chroococcus sp. positively regulated the growth of soil bacteria belonging to the genera Chitinophaga, Prevotella and Tumebacillus, which may contribute to increased soil fertility through the production of beneficial enzymes such as invertase, urease and catalase. To date, this is the first study verifying the remediation effect of non-nitrogen-fixing cyanobacteria on nitrate-contaminated soil.


Assuntos
Cianobactérias , Nitratos , Cianobactérias/metabolismo , Nitrato Redutase/metabolismo , Nitrito Redutases/metabolismo , Solo , Desnitrificação
4.
Int Immunopharmacol ; 124(Pt A): 110893, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37669598

RESUMO

Immunotherapeutic strategies targeting γδT cells are now recognized as a promising treatment method for hepatocellular carcinoma (HCC). To date, no specific antigen or antigenic epitope recognized by γδT cells has been identified, limiting their application in the field of HCC treatment. Previously, we used an established screening strategy to identify a novel HCC protein antigen recognized by γδT cells called MSP. In this study, we explored the function of MSP activated-γδT cells in HCC. Results demonstrated that the proportions of γδT cells in the peripheral blood of HCC patients and the level of IFN-γ in the serum were higher than in healthy controls. We also determined that γδT cells can bind MSP protein. MSP-activated γδT cells were shown to contain a specific CDR3δ2 sequence that supports the recognition of MSP by γδT cells. We determined that MSP is highly expressed in HCC, MSP-activated γδT cells in the peripheral blood of HCC patients express co-stimulatory molecules, and MSP-activated γδT cells directly killed HCC cells. In conclusion, we demonstrated that the novel protein ligand MSP activated γδT cells, leading to the killing of HCC cells through direct and indirect mechanisms. These findings could provide a potential new target for the clinical diagnosis and treatment of HCC and a foundation for clinical treatment strategies in HCC.

5.
Front Plant Sci ; 14: 1176648, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404529

RESUMO

Introduction: The endosphere of a plant is an interface containing a thriving community of endobacteria that can affect plant growth and potential for bioremediation. Eichhornia crassipes is an aquatic macrophyte, adapted to estuarine and freshwater ecosystems, which harbors a diverse bacterial community. Despite this, we currently lack a predictive understanding of how E. crassipes taxonomically structure the endobacterial community assemblies across distinct habitats (root, stem, and leaf). Methods: In the present study, we assessed the endophytic bacteriome from different compartments using 16S rRNA gene sequencing analysis and verified the in vitro plant beneficial potential of isolated bacterial endophytes of E. crassipes. Results and discussion: Plant compartments displayed a significant impact on the endobacterial community structures. Stem and leaf tissues were more selective, and the community exhibited a lower richness and diversity than root tissue. The taxonomic analysis of operational taxonomic units (OTUs) showed that the major phyla belonged to Proteobacteria and Actinobacteriota (> 80% in total). The most abundant genera in the sampled endosphere was Delftia in both stem and leaf samples. Members of the family Rhizobiaceae, such as in both stem and leaf samples. Members of the family Rhizobiaceae, such as Allorhizobium- Neorhizobium-Pararhizobium-Rhizobium were mainly associated with leaf tissue, whereas the genera Nannocystis and Nitrospira from the families Nannocystaceae and Nitrospiraceae, respectively, were statistically significantly associated with root tissue. Piscinibacter and Steroidobacter were putative keystone taxa of stem tissue. Most of the endophytic bacteria isolated from E. crassipes showed in vitro plant beneficial effects known to stimulate plant growth and induce plant resistance to stresses. This study provides new insights into the distribution and interaction of endobacteria across different compartments of E. crassipes Future study of endobacterial communities, using both culture-dependent and -independent techniques, will explore the mechanisms underlying the wide-spread adaptability of E. crassipesto various ecosystems and contribute to the development of efficient bacterial consortia for bioremediation and plant growth promotion.

6.
J Exp Med ; 220(8)2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37145142

RESUMO

Effective depletion of immune suppressive regulatory T cells (Tregs) in the tumor microenvironment without triggering systemic autoimmunity is an important strategy for cancer immunotherapy. Modified vaccinia virus Ankara (MVA) is a highly attenuated, non-replicative vaccinia virus with a long history of human use. Here, we report rational engineering of an immune-activating recombinant MVA (rMVA, MVA∆E5R-Flt3L-OX40L) with deletion of the vaccinia E5R gene (encoding an inhibitor of the DNA sensor cyclic GMP-AMP synthase, cGAS) and expression of two membrane-anchored transgenes, Flt3L and OX40L. Intratumoral (IT) delivery of rMVA (MVA∆E5R-Flt3L-OX40L) generates potent antitumor immunity, dependent on CD8+ T cells, the cGAS/STING-mediated cytosolic DNA-sensing pathway, and type I IFN signaling. Remarkably, IT rMVA (MVA∆E5R-Flt3L-OX40L) depletes OX40hi regulatory T cells via OX40L/OX40 interaction and IFNAR signaling. Single-cell RNA-seq analyses of tumors treated with rMVA showed the depletion of OX40hiCCR8hi Tregs and expansion of IFN-responsive Tregs. Taken together, our study provides a proof-of-concept for depleting and reprogramming intratumoral Tregs via an immune-activating rMVA.


Assuntos
Neoplasias , Vírus Vaccinia , Humanos , Vírus Vaccinia/genética , Linfócitos T CD8-Positivos , Nucleotidiltransferases/genética , Microambiente Tumoral
7.
J Med Virol ; 95(1): e28396, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36504005

RESUMO

Multiple treatment modalities for Kaposi sarcoma (KS) have been reported, including chemotherapy, radiation therapy, surgical excision, electrochemotherapy, and cryotherapy. Common topical treatments include timolol, imiquimod, and alitretinoin. We searched our institutional database for patients with ICD-9 or 10 codes for KS seen by a dermatologist with experience in KS management from July 1, 2004 to January 1, 2022. We screened patient charts to include patients who received combination therapy of cryotherapy followed by topical imiquimod three times a week for 2 months (n = 9). Patients were followed in the clinic every 3 months. Time to resolution was assessed by photographic evidence of resolution as determined by a dermatologist and corroborated with clinical documentation in patient charts. Median age (IQR) at KS diagnosis was 58 (27.5) years. All patients were male (n = 9, 100%). Majority were white (n = 7, 78%) and non-Hispanic (n = 8, 89%). Five (56%) had classic KS, one (11%) had HIV-associated KS, and three (33%) were HIV-negative men who have sex with men. Median time to resolution was 30.5 weeks, with a median of two treatments. In our study, 93% (n = 42/45) of lesions and 89% (n = 8/9) of patients experienced complete resolution during a median (range) duration of follow-up of 58 (13-209) weeks. Side effects were limited to pain during cryotherapy, occasional blister formation after cryotherapy, and mild inflammation due to imiquimod. No infections were observed. Combination therapy of cryotherapy and topical imiquimod may be an efficacious and comparatively low-risk treatment for limited, cutaneous KS.


Assuntos
Infecções por HIV , Sarcoma de Kaposi , Minorias Sexuais e de Gênero , Neoplasias Cutâneas , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Imiquimode/uso terapêutico , Sarcoma de Kaposi/tratamento farmacológico , Homossexualidade Masculina , Crioterapia , Imunoterapia , Infecções por HIV/terapia
8.
Nat Commun ; 13(1): 5312, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085288

RESUMO

Response to immunotherapies can be variable and unpredictable. Pathology-based phenotyping of tumors into 'hot' and 'cold' is static, relying solely on T-cell infiltration in single-time single-site biopsies, resulting in suboptimal treatment response prediction. Dynamic vascular events (tumor angiogenesis, leukocyte trafficking) within tumor immune microenvironment (TiME) also influence anti-tumor immunity and treatment response. Here, we report dynamic cellular-level TiME phenotyping in vivo that combines inflammation profiles with vascular features through non-invasive reflectance confocal microscopic imaging. In skin cancer patients, we demonstrate three main TiME phenotypes that correlate with gene and protein expression, and response to toll-like receptor agonist immune-therapy. Notably, phenotypes with high inflammation associate with immunostimulatory signatures and those with high vasculature with angiogenic and endothelial anergy signatures. Moreover, phenotypes with high inflammation and low vasculature demonstrate the best treatment response. This non-invasive in vivo phenotyping approach integrating dynamic vasculature with inflammation serves as a reliable predictor of response to topical immune-therapy in patients.


Assuntos
Imunoterapia , Microambiente Tumoral , Humanos , Fatores Imunológicos , Inflamação , Fenótipo
9.
Sci Rep ; 12(1): 12458, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35864136

RESUMO

Spammer detection is essentially a process of judging the authenticity of users, and thus can be regarded as a classification problem. In order to improve the classification performance, multi-classifier information fusion is usually used to realize the automatic detection of spammers by utilizing the information from multiple classifiers. However, the existing fusion strategies do not reasonably take the uncertainty from the results of different classifiers (views) into account, and the relative importance and reliability of each classifier are not strictly distinguished. Therefore, in order to detect spammers effectively, this paper develops a novel multi-classifier information fusion model based on the evidential reasoning (ER) rule. Firstly, according to the user's characterization strategy, the base classifiers are constructed through the profile-based, content-based and behavior-based. Then, the idea of multi-classifier fusion is combined with the ER rule, and the results of base classifiers are aggregated by considering their weights and reliabilities. Extensive experimental results on the real-world dataset verify the effectiveness of the proposed model.


Assuntos
Algoritmos , Reprodutibilidade dos Testes
10.
J Immunother Cancer ; 9(9)2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34593618

RESUMO

BACKGROUND: Viral-based immunotherapy can overcome resistance to immune checkpoint blockade (ICB) and fill the unmet needs of many patients with cancer. Oncolytic viruses (OVs) are defined as engineered or naturally occurring viruses that selectively replicate in and kill cancer cells. OVs also induce antitumor immunity. The purpose of this study was to compare the antitumor effects of live oncolytic vaccinia viruses versus the inactivated versions and elucidate their underlying immunological mechanisms. METHODS: We engineered a replication-competent, oncolytic vaccinia virus (OV-GM) by inserting a murine GM-CSF gene into the thymidine kinase locus of a mutant vaccinia E3L∆83N, which lacks the Z-DNA-binding domain of vaccinia virulence factor E3. We compared the antitumor effects of intratumoral (IT) delivery of live OV-GM versus heat-inactivated OV-GM (heat-iOV-GM) in a murine B16-F10 melanoma bilateral implantation model. We also generated vvDD, a well-studied oncolytic vaccinia virus, and compared the antitumor effects of live vvDD vs heat-inactivated vvDD (heat-ivvDD) in a murine A20 B-cell lymphoma bilateral tumor implantation model. RESULTS: Heat-iOV-GM infection of dendritic cells (DCs) and tumor cells in vitro induced type I interferon and proinflammatory cytokines and chemokines, whereas live OV-GM did not. IT live OV-GM was less effective in generating systemic antitumor immunity compared with heat-iOV-GM. Similar to heat-iOV-GM, the antitumor effects of live OV-GM also require Batf3-dependent CD103+ dendritic cells. When combined with systemic delivery of ICB, IT heat-iOV-GM was more effective in eradicating tumors, compared with live OV-GM. IT heat-ivvDD was also more effective in treating murine A20 B-cell lymphoma, compared with live vvDD. CONCLUSIONS: Tumor lysis induced by the replication of oncolytic vaccinia virus has a limited effect on the generation of systemic antitumor immunity. The activation of Batf3-dependent CD103+ DCs is critical for antitumor effects induced by both live OV-GM and heat-iOV-GM, with the latter being more potent than live OV-GM in inducing innate and adaptive immunity in both locally injected and distant, non-injected tumors. We propose that evaluations of both innate and adaptive immunity, induced by IT oncolytic viral immunotherapy at injected and non-injected tumors, should be included as potential biomarkers for host responses to viral therapy.


Assuntos
Imunoterapia/métodos , Terapia Viral Oncolítica/métodos , Vírus Oncolíticos/metabolismo , Animais , Feminino , Temperatura Alta , Humanos , Camundongos , Microambiente Tumoral
11.
Ecotoxicol Environ Saf ; 225: 112753, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34500384

RESUMO

This study investigated the influences of three frequently detected antibiotics in surface waters, ciprofloxacin, tetracycline and sulfamethoxazole, on the growth, photosynthetic activity, nitrogen-fixing capacity and proteomic expression profiles of Nostoc sp. PCC 7120, through a 15-day exposure test at environmentally relevant exposure doses of 50-200 ng/L. Cyanobacterial growth was stimulated by 100 ng/L and 200 ng/L of ciprofloxacin and sulfamethoxazole as well as 50-200 ng/L of tetracycline. The nitrogenase synthesis ability in each cyanobacterial cell was stimulated by 50-200 ng/L of ciprofloxacin while inhibited by 100 ng/L and 200 ng/L of tetracycline and sulfamethoxazole. At the exposure dose of 100 ng/L for each antibiotic, the variation of total nitrogen in the culture medium indicated that the nitrogen-fixing capacity of Nostoc sp. was determined by total nitrogenase concentration calculated by cell density × nitrogenase synthesis ability. Therefore, ciprofloxacin enhanced nitrogen fixation through the stimulation of both cyanobacterial growth and nitrogenase synthesis, while tetracycline and sulfamethoxazole enhanced nitrogen fixation merely through growth stimulation. At the exposure dose of 100 ng/L, only two downregulated proteins, a phosphonate ABC transporter and a methionine aminopeptidase, as well as one upregulated protein, the phenylalanine-tRNA ligase alpha subunit, were commonly shared by three antibiotic-treated groups. Ciprofloxacin upregulated proteins related to nitrogen fixation, carbon catabolism and biosynthesis, but downregulated photosynthesis-related proteins. In contrast, tetracycline and sulfamethoxazole increased the photosynthetic activity of Nostoc sp. through upregulating photosynthesis-related proteins, but downregulated proteins related to nitrogen fixation, carbon catabolism and biosynthesis. The resistance of Nostoc sp. PCC 7120 to three target antibiotics were related with the responses of RNA synthesis regulatory proteins. Stimulation of cyanobacterial nitrogen fixation by antibiotic contaminants could aggravate eutrophication in aquatic environments.


Assuntos
Nostoc , Antibacterianos/toxicidade , Fixação de Nitrogênio , Fotossíntese , Proteômica
12.
Cell Rep ; 29(8): 2461-2472.e6, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31747613

RESUMO

The nuclear exosome targeting (NEXT) complex is responsible for specific nuclear RNA degradation in mammalian cells. However, its function in development remains unknown. Here, we find that the depletion of a central factor of the NEXT complex, Zcchc8, in mouse results in developmental defects, a shortened lifespan, and infertility. We find that Zcchc8-deficient embryonic stem cells (ESCs) exhibit proliferation abnormalities and reduced developmental potencies. Importantly, the transcripts of retrotransposon element LINE1 are found to be targeted by Zcchc8 and degraded by a Zcchc8-mediated mechanism. We further find that sustained expression of higher levels of LINE1 RNA is detected in maternal Zcchc8-depleted oocytes and embryos. Zcchc8-depleted oocytes show higher chromatin accessibility and developmental defects in both meiotic maturation and embryogenesis after fertilization. Collectively, our study defines Zcchc8-mediated RNA degradation as an important post-transcription regulation of LINE1 transcripts in early embryos and ESCs, which play vital roles in the pluripotency and early development.


Assuntos
Células-Tronco Embrionárias/metabolismo , Exossomos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Ligação a RNA/metabolismo , RNA/metabolismo , Animais , Núcleo Celular/genética , Núcleo Celular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Camundongos , Proteínas Nucleares/genética , Oócitos/metabolismo , Proteínas de Ligação a RNA/genética
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