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1.
Proc Natl Acad Sci U S A ; 121(29): e2401834121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38976739

RESUMO

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related death worldwide, but the underlying molecular mechanisms remain largely unclear. The transcription factor (TF) specificity protein 1 (SP1) plays a crucial role in the development of various cancers, including LUAD. Recent studies have indicated that master TFs may form phase-separated macromolecular condensates to promote super-enhancer (SE) assembly and oncogene expression. In this study, we demonstrated that SP1 undergoes phase separation and that its zinc finger 3 in the DNA-binding domain is essential for this process. Through Cleavage Under Targets & Release Using Nuclease (CUT&RUN) using antibodies against SP1 and H3K27ac, we found a significant correlation between SP1 enrichment and SE elements, identified the regulator of the G protein signaling 20 (RGS20) gene as the most likely target regulated by SP1 through SE mechanisms, and verified this finding using different approaches. The oncogenic activity of SP1 relies on its phase separation ability and RGS20 gene activation, which can be abolished by glycogen synthase kinase J4 (GSK-J4), a demethylase inhibitor. Together, our findings provide evidence that SP1 regulates its target oncogene expression through phase separation and SE mechanisms, thereby promoting LUAD cell progression. This study also revealed an innovative target for LUAD therapies through intervening in SP1-mediated SE formation.


Assuntos
Adenocarcinoma de Pulmão , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , Proteínas RGS , Fator de Transcrição Sp1 , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genética , Humanos , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Proteínas RGS/metabolismo , Proteínas RGS/genética , Linhagem Celular Tumoral , Animais , Elementos Facilitadores Genéticos , Progressão da Doença , Camundongos , Separação de Fases
2.
Front Immunol ; 15: 1410928, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903520

RESUMO

In recent years, with the deepening understanding of the gut microbiota, it has been recognized to play a significant role in the development and progression of diseases. Particularly in gastrointestinal tumors, the gut microbiota influences tumor growth by dysbiosis, release of bacterial toxins, and modulation of host signaling pathways and immune status. Immune checkpoint inhibitors (ICIs) have greatly improved cancer treatment efficacy by enhancing immune cell responses. Current clinical and preclinical studies have demonstrated that the gut microbiota and its metabolites can enhance the effectiveness of immunotherapy. Furthermore, certain gut microbiota can serve as biomarkers for predicting immunotherapy responses. Interventions targeting the gut microbiota for the treatment of gastrointestinal diseases, especially colorectal cancer (CRC), include fecal microbiota transplantation, probiotics, prebiotics, engineered bacteria, and dietary interventions. These approaches not only improve the efficacy of ICIs but also hold promise for enhancing immunotherapy outcomes. In this review, we primarily discuss the role of the gut microbiota and its metabolites in tumors, host immunity, and immunotherapy.


Assuntos
Microbioma Gastrointestinal , Imunoterapia , Humanos , Microbioma Gastrointestinal/imunologia , Imunoterapia/métodos , Animais , Disbiose/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Neoplasias/microbiologia , Probióticos/uso terapêutico , Transplante de Microbiota Fecal , Inibidores de Checkpoint Imunológico/uso terapêutico , Prebióticos/administração & dosagem
3.
Nat Microbiol ; 9(7): 1686-1699, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898217

RESUMO

The continuing emergence of invasive fungal pathogens poses an increasing threat to public health. Here, through the China Hospital Invasive Fungal Surveillance Net programme, we identified two independent cases of human infection with a previously undescribed invasive fungal pathogen, Rhodosporidiobolus fluvialis, from a genus in which many species are highly resistant to fluconazole and caspofungin. We demonstrate that R. fluvialis can undergo yeast-to-pseudohyphal transition and that pseudohyphal growth enhances its virulence, revealed by the development of a mouse model. Furthermore, we show that mouse infection or mammalian body temperature induces its mutagenesis, allowing the emergence of hypervirulent mutants favouring pseudohyphal growth. Temperature-induced mutagenesis can also elicit the development of pan-resistance to three of the most commonly used first-line antifungals (fluconazole, caspofungin and amphotericin B) in different Rhodosporidiobolus species. Furthermore, polymyxin B was found to exhibit potent activity against the pan-resistant Rhodosporidiobolus mutants. Collectively, by identifying and characterizing a fungal pathogen in the drug-resistant genus Rhodosporidiobolus, we provide evidence that temperature-dependent mutagenesis can enable the development of pan-drug resistance and hypervirulence in fungi, and support the idea that global warming can promote the evolution of new fungal pathogens.


Assuntos
Antifúngicos , Mutagênese , Animais , Camundongos , Humanos , Virulência/genética , Antifúngicos/farmacologia , China , Temperatura Corporal , Modelos Animais de Doenças , Ascomicetos/genética , Ascomicetos/patogenicidade , Ascomicetos/efeitos dos fármacos , Caspofungina/farmacologia , Testes de Sensibilidade Microbiana , Fluconazol/farmacologia , Micoses/microbiologia , Farmacorresistência Fúngica Múltipla/genética , Farmacorresistência Fúngica/genética
4.
Cell Host Microbe ; 32(2): 276-289.e7, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38215741

RESUMO

Bacterial persisters, a subpopulation of genetically susceptible cells that are normally dormant and tolerant to bactericides, have been studied extensively because of their clinical importance. In comparison, much less is known about the determinants underlying fungicide-tolerant fungal persister formation in vivo. Here, we report that during mouse lung infection, Cryptococcus neoformans forms persisters that are highly tolerant to amphotericin B (AmB), the standard of care for treating cryptococcosis. By exploring stationary-phase indicator molecules and developing single-cell tracking strategies, we show that in the lung, AmB persisters are enriched in cryptococcal cells that abundantly produce stationary-phase molecules. The antioxidant ergothioneine plays a specific and key role in AmB persistence, which is conserved in phylogenetically distant fungi. Furthermore, the antidepressant sertraline (SRT) shows potent activity specifically against cryptococcal AmB persisters. Our results provide evidence for and the determinant of AmB-tolerant persister formation in pulmonary cryptococcosis, which has potential clinical significance.


Assuntos
Criptococose , Cryptococcus neoformans , Fungicidas Industriais , Pneumonia , Animais , Camundongos , Anfotericina B/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Criptococose/microbiologia , Fungicidas Industriais/farmacologia , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia
5.
Heliyon ; 9(9): e19799, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810047

RESUMO

Ferroptosis was first proposed in 2012, a new form of cell death. Autophagy plays a crucial role in cell clearance and maintaining homeostasis. Autophagy is involved in the initial step of ferroptosis under the action of histone elements such as NCOA4, RAB7A, and BECN1. Ferroptosis and autophagy are involved in tumor progression, treatment, and drug resistance in the tumor microenvironment. In this review, we described the mechanisms of ferroptosis, autophagy, and tumor and immunotherapy, respectively, and emphasized the relationship between autophagy-related ferroptosis and tumor.

6.
Adv Drug Deliv Rev ; 200: 115007, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37437715

RESUMO

Human pathogenic fungi pose a serious threat to human health and safety. Unfortunately, the limited number of antifungal options is exacerbated by the continuous emergence of drug-resistant variants, leading to frequent drug treatment failures. Recent studies have also highlighted the clinical importance of other modes of fungal survival of antifungal treatment, including drug tolerance and persistence, pointing to the complexity of the fungal response to antifungal drugs. A lack of understanding of the fungal drug response has hampered the identification of new targets, the development of alternative antifungal strategies and the design of appropriate delivery systems. In this review we summarize recent advances in the study of antifungal resistance, tolerance and persistence, with an emphasis on promising drug targets and drug delivery systems that may yield important insights into the development of new or improved antifungal therapies against fungal infections.


Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Micoses/tratamento farmacológico , Fungos/fisiologia , Tolerância a Medicamentos , Sistemas de Liberação de Medicamentos
7.
mLife ; 1(1): 79-91, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38818325

RESUMO

Cryptococcus neoformans and its sister species Cryptococcus deuterogattii are important human fungal pathogens. Despite their phylogenetically close relationship, these two Cryptococcus pathogens are greatly different in their clinical characteristics. However, the determinants underlying the regulatory differences of their pathogenicity remain largely unknown. Here, we show that the forkhead transcription factor Hcm1 promotes infection in C. neoformans but not in C. deuterogattii. Monitoring in vitro and in vivo fitness outcomes of multiple clinical isolates from the two pathogens indicates that Hcm1 mediates pathogenicity in C. neoformans through its key involvement in oxidative stress defense. By comparison, Hcm1 is not critical for antioxidation in C. deuterogattii. Furthermore, we identified SRX1, which encodes the antioxidant sulfiredoxin, as a conserved target of Hcm1 in two Cryptococcus pathogens. Like HCM1, SRX1 had a greater role in antioxidation in C. neoformans than in C. deuterogattii. Significantly, overexpression of SRX1 can largely rescue the defective pathogenicity caused by the absence of Hcm1 in C. neoformans. Conversely, Srx1 is dispensable for virulence in C. deuterogattii. Overall, our findings demonstrate that the difference in the contribution of the antioxidant sulfiredoxin to oxidative stress defense underlies the Hcm1-mediated regulatory differences of pathogenicity in two closely related pathogens.

8.
Chem Biol Interact ; 348: 109653, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516974

RESUMO

Angiotensin II, the effector peptide of the renin-angiotensin system, is not only a pivotal peptide implicated in the regulation of blood pressure but also a key mediator of the inflammatory processes that play an important role in the pathology of hypertension-related cSVD. Harpagide is the major bioactive constituent of Scrophulariae Radix widely used in traditional Chinese medicine for numerous diseases including hypertension. The present study aimed to investigate the effect of harpagide on Ang II-induced neuroinflammation and the potential mechanism. Pretreated with harpagide or resatorvid (the TLR4 pathway inhibitor), BV2 cells were treated with Ang II or LPS (the TLR4 activator). NO, pro-inflammatory cytokines, the proteins on TLR4/MyD88/NF-κB signaling pathway and the expression of CD86, CD206, TREM2 in BV2 cells were detected respectively. Subsequently, the effects of harpagide on neurotoxicity and BBB destruction triggered by Ang II-induced neuroinflammation were investigated in the co-cultures of BV2 microglia/HT22 hippocampal neurons, BV2 microglia/bEnd.3 endotheliocyte and BV2 microglia/BBB monolayer model. We found that Ang II converted microglia into M1 state and resulted in neuroinflammation through activating TLR4/MyD88/NF-κB signaling pathway. It also triggered the imbalance of TLR4/TREM2 in microglia. Ang II-mediated inflammation microglia further led to neuronal apoptosis and BBB damage. Harpagide showed the effect of alleviating Ang II-mediated neuroinflammation as well as the resulting neurotoxicity and BBB destruction through inhibiting the TLR4/MyD88/NF-κB pathway. The anti-inflammatory and neuroprotective effect of harpagide suggested that it might be a potential therapeutic strategy in hypertensive cSVD.


Assuntos
Angiotensina II/farmacologia , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Glicosídeos Iridoides/farmacologia , Microglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Piranos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Linhagem Celular , Humanos , Microglia/citologia , Microglia/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Receptor 4 Toll-Like/metabolismo
9.
ACS Omega ; 6(51): 35600-35606, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34984291

RESUMO

A self-lubricating hydrogel filament was achieved by establishing an in situ photocuring system and using camphorquinone/diphenyl iodonium hexafluorophosphate (CQ/DPI) as the blue-light photoinitiators, acrylamide (AM) and N,N-dimethylacrylamide (DMAA) as the monomers, polyethylene glycol diacrylate (PEGDA) as the cross-linker, and lecithin as the lipid lubricant. The blue-light photopolymerization efficiency and the photorheological properties of the hydrogel precursor were investigated by photodifferential scanning calorimetry and a photorheological system. With the increase of DMAA, the photopolymerization efficiency of the precursor improved, while the elasticity of poly(DMAA/AM) decreased accordingly. The physical cross-linking effect between lecithin and the poly(DMAA/AM) network led to improved polymerization properties and elasticity. The lipid-based boundary layer at the hydrogel surface endowed the self-lubrication of the hydrogel filament. The extruded hydrogel filaments exhibited excellent mechanical properties and weavability, which were expected to play a realistic role in soft robots and bioengineering.

10.
Mol Med Rep ; 22(4): 3358-3366, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32945470

RESUMO

Infantile hemangioma (IH) is one of the most common vascular tumors that occurs during childhood, but its pathogenesis is currently not completely understood. Even though lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays vital roles in tumorigenesis of malignant tumors, its roles in IH remain unclear. Therefore, we evaluate the function of lncRNA NEAT1 in IH. Reverse transcription­-quantitative PCR indicated that IH tissues exhibited high expression levels of NEAT1 and hypoxia­inducible factor 1α (HIF1α), and low expression levels of the microRNA (miR)­33a­5p. Small interfering RNA­mediated depletion of NEAT1 suppressed hemangioma endothelial cell (HemEC) proliferation, migration and invasion. The data suggested that NEAT1 positively regulated HIF1α expression by sponging miR­33a­5p in HemECs. miR­33a­5p overexpression or HIF1α silencing also acted to suppress HemEC proliferation, migration and invasion. Furthermore, the results indicated that the NEAT1/miR­33a­5p/HIF1α axis regulated the NF­κB signaling pathway. Collectively, the results revealed that depletion of lncRNA NEAT1 suppressed the tumorigenesis of IH by competitively binding miR­33a­5p and thereby stimulating the HIF1α/NF­κB signaling pathway.


Assuntos
Hemangioma/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Regiões 3' não Traduzidas , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lactente , Masculino , NF-kappa B/metabolismo , RNA Longo não Codificante/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
11.
Mol Med Rep ; 10(4): 1765-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25118798

RESUMO

Accumulative evidence has demonstrated that inflammation has an important role in human papillomavirus (HPV) oncogenicity. However, the effects of high mobility group protein box 1 (HMGB1)-toll like receptor 4 (TLR4) signaling pathway associated inflammation on epidermal warts caused by HPV remain unclear. The present study investigated the HMGB1, TLR4 and nuclear factor-κB p65 expression in condyloma acuminatum (CA) and verruca vulgaris (VV). Immunohistochemistry and western blot analysis revealed that p65 expression in epithelial nuclei in VV and CA was significantly higher than in normal skin (NS) (P<0.01), and p65 in CA was higher than in VV but this difference was not significant. The level of extracellular HMGB1 increased significantly and progressively from NS to VV to CA (P<0.05). The level of TLR4 on the surface of epithelial membranes in the CA samples was significantly higher than in NS (P<0.01), and TLR4 in VV samples was significantly lower than in NS (P<0.01). There was a positive correlation between p65 expression in the epithelial nuclei and HMGB1 in the epithelial intercellular spaces (r=0.5199, P<0.01). These findings indicate that inflammation is intensified in warts caused by HPV. HMGB1-TLR4 pathway-associated inflammation may therefore have a pivotal role in CA. HMGB1, rather than TLR4, may be a vital mediator of inflammation in VV. Therapies targeting HMGB1 may be a potential strategy for the treatment of HPV-associated warts.


Assuntos
Proteína HMGB1/metabolismo , Papillomaviridae/patogenicidade , Receptor 4 Toll-Like/metabolismo , Verrugas/patologia , Núcleo Celular/metabolismo , Espaço Extracelular/metabolismo , Humanos , Imuno-Histoquímica , Fator de Transcrição RelA/metabolismo , Verrugas/metabolismo
12.
BMC Cancer ; 13: 311, 2013 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-23803172

RESUMO

BACKGROUND: High mobility group protein box 1 (HMGB1) is a DNA binding protein located in nucleus. It is released into extracellular fluid where it acts as a novel proinflammatory cytokine which interacts with Toll like receptor 4 (TLR4) to activate nuclear factor-κB (NF-κB). This sequence of events is involved in tumor growth and progression. However, the effects of HMGB1, TLR4 and NF-κB on epidermal tumors remain unclear. METHODS: Human epidermal tumor specimens were obtained from 96 patients. Immunohistochemistry was used to detect expression of HMGB1, TLR4 and NF-κB p65 in human epidermal tumor and normal skin specimens. Western blot analysis was used to detect the expression of NF-κB p65 in epithelial cell nuclei in human epidermal tumor and normal tissues. RESULTS: Immunohistochemistry and western blot analysis indicated a progressive but statistically significant increase in p65 expression in epithelial nuclei in benign seborrheic keratosis (SK), precancerous lesions (PCL), low malignancy basal cell carcinoma (BCC) and high malignancy squamous cell carcinoma (SCC) (P <0.01). The level of extracellular HMGB1 in SK was significantly higher than in normal skin (NS) (P <0.01), and was higher than in SCC but without statistical significance. The level of TLR4 on epithelial membranes of SCC cells was significantly higher than in SK, PCL, BCC and NS (P <0.01). There was a significant positive correlation between p65 expression in the epithelial nuclei and TLR4 expression on the epithelial cell membranes (r = 0.3212, P <0.01). CONCLUSIONS: These findings indicate that inflammation is intensified in parallel with increasing malignancy. They also indicate that the TLR4 signaling pathway, rather than HMGB1, may be the principal mediator of inflammation in high-grade malignant epidermal tumors. Combined detection of p65 in the epithelial nuclei and TLR4 on the epithelial membranes may assist the accurate diagnosis of malignant epidermal tumors.


Assuntos
Carcinoma Basocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Proteína HMGB1/metabolismo , Lesões Pré-Cancerosas/metabolismo , Neoplasias Cutâneas/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismo , Análise de Variância , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Espaço Extracelular/metabolismo , Humanos , Ceratose Seborreica/metabolismo , Transdução de Sinais , Pele/metabolismo
13.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(11): 1171-4, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23172532

RESUMO

OBJECTIVE: To evaluate whether neutrophil-lymphocyte ratio(NLR) predicts risk of recurrence in patients with advanced colon cancer undergoing curative resection followed by adjuvant chemotherapy. METHODS: A total of 149 patients with advanced colon cancer undergoing curative resection followed by adjuvant chemotherapy(FOLFOX6 protocol) were included. NLR was calculated preoperatively and before chemotherapy. The changes in NLR and the predictive value of NLR for prognosis were analyzed. RESULTS: The NLR of 149 patients was 2.8±1.5. NLR of 3.5 was identified according to the ROC curve. NLR<3.5 and NLR≥3.5 were classified as low and high NLR group, respectively. The 5-year recurrence-free survival(RFS) of patients with high preoperative NLR(n=22) was significantly worse than that of those with low preoperative NLR(n=127)(50.9% vs. 76.4%, P=0.025). The difference of 5-year RFS between high pre-chemotherapy NLR group(n=34) and low pre-chemotherapy NLR group(n=115) was statistically significant(50.1% vs. 71.4%, P=0.032). The 5-year RFS was 79.5% in patients with low preoperative NLR converting to high pre-chemotherapy NLR(n=16), similar to the group with high pre-chemotherapy group(P=0.077). The 5-year RFS was 17.7% in patients with high preoperative NLR reverting to low pre-chemotherapy NLR(n=12), similar to the group with low pre-chemotherapy group(P=0.978). There was significant difference in 5-year RFS between the postoperatively elevated group and postoperatively decreased group(P=0.036). CONCLUSION: An elevated blood NLR may be a biomarker of poor RFS in patients with advanced colon cancer after curative resection and chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/terapia , Linfócitos/imunologia , Neutrófilos/imunologia , Adulto , Idoso , Quimioterapia Adjuvante , Neoplasias do Colo/sangue , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/uso terapêutico , Prognóstico
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