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1.
J Neurosci ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147590

RESUMO

Ribbon synapses of inner hair cells are uniquely designed for ultrafast and indefatigable neurotransmission of the sound. The molecular machinery ensuring the efficient, compensatory recycling of the synaptic vesicles, however, remains elusive. This study showed that hair cell knockout of murine Dmxl2, whose human homolog is responsible for non-syndromic sensorineural hearing loss DFNA71, resulted in auditory synaptopathy by impairing synaptic endocytosis and recycling. The mutant mice in the C57BL/6J background of either sex had mild hearing loss with severely diminished wave-I amplitude of the auditory brainstem response. Membrane capacitance measurements of the inner hair cells revealed deficiency in sustained synaptic exocytosis and endocytic membrane retrieval. Consistent with the electrophysiological findings, 3D electron microscopy reconstruction showed reduced reserve pool of synaptic vesicles and endocytic compartments, while the membrane-proximal and ribbon-associated vesicles remain intact. Our results propose an important role of DMXL2 in hair cell endocytosis and recycling of the synaptic vesicles.Significance Statement The molecular basis underlying efficient recycling of the ribbon synaptic vesicles in cochlear hair cells remains elusive. In this study, investigation of a hair cell-specific knockout mouse for Dmxl2 identifies its import roles in endocytosis and recycling of the auditory synaptic vesicles. The mutant mice display auditory synaptopathy, a common feature for noise-induced hearing loss and age-related hearing loss. The inner hair cells show deficiency in sustained synaptic exocytosis and endocytic membrane retrieval with reduced reserve pool of synaptic vesicles and endocytic compartments. Our results provide new insights into the molecular machinery ensuring ultrafast and indefatigable neurotransmission of the sound.

2.
Apoptosis ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222275

RESUMO

Lung cancer is one of the most common malignant tumors. Despite decades of research, the treatment of lung cancer remains challenging. Non-small cell lung cancer (NSCLC) is the primary type of lung cancer and is a significant focus of research in lung cancer treatment. The deubiquitinase ubiquitin-specific protease 28 (USP28) plays a role in the progression of various tumors and serves as a potential therapeutic target. This study aims to determine the role of USP28 in the progression of NSCLC. We examined the impact of the USP28 inhibitor AZ1 on the cell cycle, apoptosis, DNA damage response, and cellular immunogenicity in non-small cell lung cancer. We observed that AZ1 and siUSP28 induce DNA damage, leading to the activation of Noxa-mediated mitochondrial apoptosis. The dsDNA and mtDNA released from DNA damage and mitochondrial apoptosis activate tumor cell immunogenicity through the cGAS-STING signaling pathway. Simultaneously, targeting USP28 promotes the degradation of c-MYC, resulting in cell cycle arrest and inhibition of DNA repair. This further promotes DNA damage-induced cell apoptosis mediated by the Noxa protein, thereby enhancing tumor cell immunogenicity mediated by dsDNA and mtDNA. Moreover, we found that the combination of AZ1 and cisplatin (DDP) can enhance therapeutic efficacy, thereby providing a new strategy to overcome cisplatin resistance in NSCLC. These findings suggest that targeting USP28 and combining it with cisplatin are feasible strategies for treating NSCLC.

3.
Br J Cancer ; 128(7): 1223-1235, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36646807

RESUMO

BACKGROUND: Mental stress-induced neurotransmitters can affect the immune system in various ways. Therefore, a better understanding of the role of neurotransmitters in the tumour immune microenvironment is expected to promote the development of novel anti-tumour therapies. METHODS: In this study, we analysed the plasma levels of neurotransmitters in anti-programmed cell death protein 1 (PD-1) monoclonal antibody (mAb)-resistance patients and sensitive patients, to identify significantly different neurotransmitters. Subsequently, animal experiments and experiments in vitro were used to reveal the specific mechanism of norepinephrine's (NE) effect on immunotherapy. RESULTS: The plasma NE levels were higher in anti-PD-1 mAb-resistance patients, which may be the main cause of anti-PD-1 mAb resistance. Then, from the perspective of the immunosuppressive microenvironment to explore the specific mechanism of NE-induced anti-PD-1 mAb resistance, we found that NE can affect the secretion of C-X-C Motif Chemokine Ligand 9 (CXCL9) and adenosine (ADO) in tumour cells, thereby inhibiting chemotaxis and function of CD8+ T cells. Notably, the WNT7A/ß-catenin signalling pathway plays a crucial role in this progression. CONCLUSION: NE can affect the secretion of CXCL9 and ADO in tumour cells, thereby inhibiting chemotaxis and the function of CD8+ T cells and inducing anti-PD-1 mAb resistance in lung adenocarcinoma (LUAD).


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Animais , Linfócitos T CD8-Positivos , Norepinefrina/farmacologia , Linhagem Celular Tumoral , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Microambiente Tumoral
4.
BMC Cancer ; 23(1): 28, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611139

RESUMO

OBJECTIVE: Targeting deubiquitinases (DUBs) has emerged as a promising avenue for anticancer drug development. However, the effect and mechanism of pan-DUB inhibitor EOAI on non-small cell lung cancer (NSCLC) remains to be studied. MATERIALS AND METHODS: The expression of ubiquitin-specific peptidase 5 (USP5) in NSCLC was evaluated by immunohistochemistry. The effect of the USP5 inhibitor, EOAI, on NSCLC cell growth and cell cycle was evaluated by CCK-8 and PI staining. Apoptosis was detected by Annexin V-FITC/PI double staining. Autophagy was examined by LC3 immunofluorescence. Comet assay and γ-H2AX immunofluorescence staining were used to detect DNA damage, and Western blotting was used to detect the expression of apoptosis, cycle, autophagy and DNA damage-related proteins. In vivo experiments demonstrated the effect of EOAI on NSCLC. RESULTS: We also found that USP5 was significantly upregulated in NSCLC tissues in this study. In addition, we show that EOAI can cause DNA damage in NSCLC cells while modulating the transcriptional activity of P53, thereby inducing cell cycle arrest in NSCLC cells, autophagy and apoptosis. In vivo experiments have shown that EOAI can inhibit tumors and synergistically enhance the anti-tumor effect of cisplatin. CONCLUSION: USP5-mediated epigenetic regulation of oncogenes promotes the occurrence of NSCLC, which provides ideas for developing potential targeted therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Epigênese Genética , Linhagem Celular Tumoral , Dano ao DNA , Proteases Específicas de Ubiquitina/metabolismo , Apoptose , Autofagia , Proliferação de Células
5.
World J Surg Oncol ; 21(1): 78, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36872314

RESUMO

BACKGROUND: The purpose of our study is to investigate the expression level and prognostic value of serum α-hydroxybutyrate dehydrogenase (α-HBDH) in lung cancer (LC) patients. METHOD: LC patients treated in the Department of Oncology, Shaanxi Provincial Cancer Hospital from January 2014 to December 2016 were included in this study, all of whom underwent serological detection of α-HBDH prior to admission, and were enrolled in follow-up 5-year survival. Comparing the differences between high group and normal groups based on α-HBDH and LDH expression via clinicopathological parameters and laboratory data. Univariate and multivariate regression and overall survival (OS) were analyzed to explore whether elevated α-HBDH was an independent risk factor for LC, compared to LDH. RESULTS: Multivariate regression analysis showed that age (P = 0.018), liver metastasis (P = 0.011), α-HBDH (P = 0.015), and neutrophil-to-lymphocyte ratio (NLR) (P = 0.031) were independent prognostic factors affecting OS in LC patients. The overall diagnostic efficacy of α-HBDH (AUC = 0.887) was higher than that of LDH (AUC = 0.709) in the ROC curve. The sensitivity was significantly higher of α-HBDH (sensitivity: 76.06%, specificity: 94.87%) compared with LDH (sensitivity: 49.30%, specificity: 94.87%). The median of OS was more significant in the high-α-HBDH group (6.4 months) than in the normal-α-HBDH group (12.7 months) (P = 0.023). The median of OS was significant in the high-LDH (> 245 U/L) group at 5.8 months and 12.0 months in the normal-LDH (≤ 245 U/L) group (P = 0.068). CONCLUSIONS: Elevated expression of α-HBDH may indicate a poor prognosis of LC patients. It has a higher sensitivity than LDH and can be used as a potential early biomarker and an independent risk factor predicting the prognosis of LC survival.


Assuntos
Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Prognóstico , Institutos de Câncer , Hospitalização
6.
J Clin Lab Anal ; 36(6): e24462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35522136

RESUMO

PURPOSE: To investigate the expression of heat shock protein 90α (HSP90α) in patients with lung cancer (LC) and the clinical value of HSP90α and other related markers in the diagnosis of LC. METHODS: Of 335 patients enrolled in the study cohort, 175 were screened for LC and 160 were healthy (HC). The plasma levels of HSP90α and related markers (CEA, NSE, CYFRA21-1 and ProGRP) were detected in all individuals in the cohort by enzyme-linked immunosorbent assay (ELISA). Groups were divided according to gender (male/female), age (≤60 years/>60 years), types of LC (small-cell carcinoma, squamous carcinoma and adenocarcinoma), staging (I, II, III and IV) and metastasis (metastasis and non-metastasis) separately. Wilcoxon Mann-Whitney test and Kruskal-Wallis test were used to compare statistical differences between two groups/among the multiple groups for each factor of HSP90α. The r-value and Kappa were used to compare HSP90α with related markers, and the receiver operating curve (ROC) was used to evaluate the efficacy of plasma HSP90α in predicting LC. RESULTS: No statistical difference was found in the plasma level of HSP90α among different age and gender groups (p > 0.05). In the group divided by LC type, staging and metastasis status, there were statistical differences among different groups in HSP90α level (p < 0.05). The levels of HSP90α, CEA, NSE, CYFRA21-1 and ProGRP in LC groups were significantly higher than HC (p < 0.001). R values of HSP90α correlated with other related markers in the diagnosis of LC (p < 0.05). Although HSP90α and other related markers did not fit the satisfactory conformance, in terms of the positive rate of diagnosis, it was statistically differences in the diagnostic positive rate between HSP90α and each marker (p < 0.01). ROC analysis showed that a plasma HSP90α cut-off point of 50.02 ng/ml had an optimal predictive value for LC. CONCLUSIONS: HSP90α has significant clinical value in early screening and diagnosis of LC. The combined application of HSP90α and related markers can improve the positive rate of early diagnosis of LC effectively.


Assuntos
Antígeno Carcinoembrionário , Neoplasias Pulmonares , Antígenos de Neoplasias , Biomarcadores Tumorais , Feminino , Humanos , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade
7.
Neural Plast ; 2020: 6350479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617096

RESUMO

Hearing loss is a highly heterogeneous disorder, with more than 60% of congenital cases caused by genetic factors. This study is aimed at identifying the genetic cause of congenital hearing loss in a Chinese Han family. Auditory evaluation before and after cochlear implantation and targeted next-generation sequencing of 140 deafness-related genes were performed for the deaf proband. Compound heterozygous mutations c.3658_3662del (p. E1221Wfs∗23) and c.6177+1G>T were identified in MYO15A as the only candidate pathogenic mutations cosegregated with the hearing loss in this family. These two variants were absent in 200 normal-hearing Chinese Hans and were classified as likely pathogenic and pathogenic, respectively, based on the ACMG guideline. Our study further expanded the mutation spectrum of MYO15A as the c.3658_3662del mutation is novel and confirmed that deaf patients with recessive MYO15A mutations have a good outcome for cochlear implantation.


Assuntos
Implante Coclear , Surdez/genética , Mutação , Miosinas/genética , Adolescente , Audiologia , China , Surdez/diagnóstico por imagem , Surdez/cirurgia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imageamento por Ressonância Magnética , Masculino , Linhagem , Tomografia Computadorizada por Raios X
8.
Apoptosis ; 24(9-10): 826-836, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31342239

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most malignant tumors in east Asia. However, the molecular mechanism underlying its progression remains unclear. The ubiquitin-proteasome system (UPS) is a central mechanism for protein degradation and turnover. Accumulating evidence showed that more and more deubiquitinases could serve as attractive anti-cancer target. The expression of USP14 and UCH37 in esophagus squamous cell carcinoma tissues were examined by immunohistochemistry and western blot assays. Effect of b-AP15, a USP14 and UCH37 inhibitor, on ESCC cell growth was evaluated by cell viability assay. After cell lines being treated with b-AP15, cell cycle, apoptosis and the expression of related proteins were further explored to investigate the anti-ESCC mechanism of b-AP15. Results showed that deubiquitinating enzymes (DUBs) USP14 and UCH37 expressed at higher levels in ESCC tissues than in adjacent tissues. b-AP15 could inhibit cell proliferation and induce G2/M cell cycle arrest and apoptosis in ESCC cells. Mechanistically, b-AP15 treatment triggered Noxa-dependent apoptosis, which was regulated by c-Myc. Silencing Noxa and c-Myc could reduce b-AP15-induced apoptosis in ESCC cells. Our results revealed a novel mechanism of anti-tumor activity of b-AP15 in ESCC, and b-AP15 could be used as a potential therapeutic agent in ESCC.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Piperidonas/farmacologia , Ubiquitina Tiolesterase/metabolismo , Anticarcinógenos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Neoplasias Esofágicas/tratamento farmacológico , Inativação Gênica , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fatores de Transcrição/genética , Ubiquitina Tiolesterase/efeitos dos fármacos
9.
Mol Carcinog ; 58(1): 42-54, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30182448

RESUMO

Increasing evidence suggests that deubiquitinase USP7 participates in tumor progression by various mechanisms and serves as a potential therapeutic target. However, its expression and role in esophageal cancer remains elusive; the anti-cancer effect by targeting USP7 still needs to be investigated. Here, we reported that USP7 was overexpressed in esophageal squamous cell carcinoma (ESCC) tissues compared with adjacent tissues, implying that USP7 was an attractive anticancer target of ESCC. Pharmaceutical or genetic inactivation of USP7 inhibited esophageal cancer cells growth in vitro and in vivo and induced apoptosis. Mechanistically, inhibition of USP7 accumulated poly-ubiquitinated proteins, activated endoplasmic reticulum stress, and increased expression of ATF4, which transcriptionally upregulated expression of NOXA and induced NOXA-mediated apoptosis. These results provide an evidence for clinical investigation of USP7 inhibitors for the treatment of ESCC.


Assuntos
Apoptose , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Neoplasias Esofágicas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Peptidase 7 Específica de Ubiquitina/metabolismo , Animais , Biomarcadores Tumorais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Tiofenos/farmacologia , Células Tumorais Cultivadas , Peptidase 7 Específica de Ubiquitina/antagonistas & inibidores , Peptidase 7 Específica de Ubiquitina/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Bioorg Chem ; 92: 103190, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31465969

RESUMO

A series of novel indoline derivatives were synthesized and evaluated for antiproliferative activity against four selected cancer cell lines (Hela, A549, HepG2 and KYSE30). Among them, compound 20 displayed the potent inhibition activity against esophageal cancer cells (Kyse30, Kyse450, Kyse510 and EC109). Cellular mechanism studies in esophageal squamous cell carcinoma (ESCC) cells elucidated compound 20 inhibited cell growths in vitro and in vivo, reduced colony formation, arrested cell cycle at M phase, and induced Noxa-dependent apoptosis in ESCC. Importantly, compound 20 was identified as a novel Noxa mediated apoptosis inducer. These results suggested that compound 20 might be a promising anticancer agent with potential for development of further clinical applications.


Assuntos
Antineoplásicos/química , Neoplasias Esofágicas/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Indóis/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Indóis/farmacologia , Estrutura Molecular , RNA Interferente Pequeno/metabolismo , Relação Estrutura-Atividade
11.
Adv Exp Med Biol ; 1130: 73-92, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30915702

RESUMO

It is estimated that at least 50% of congenital or childhood hearing loss is attributable to genetic causes. In non-syndromic hearing loss, which accounts for 70% of genetic hearing loss, approximately 80% of cases are autosomal recessive, 15% autosomal dominant, and 1-2% mitochondrial or X-linked. In addition, 30% of genetic hearing loss is syndromic. The genetic causes of hearing loss are highly heterogeneous. So far, more than 140 deafness-related genes have been discovered. Studies on those genes tremendously increased our understanding of the inner ear functions at the molecular level. It also offers important information for the patients and allows personalized and accurate genetic counseling. In many cases, genetic diagnosis of hearing loss can help to avoid unnecessary and costly clinical testing, offer prognostic information, and guide future medical management. On the other hand, a variety of gene therapeutic approaches have been developed aiming to relieve or converse the hearing loss due to genetic causes. Prevention of genetic hearing loss is feasible through prepregnancy and prenatal genetic diagnosis and counseling.


Assuntos
Surdez/diagnóstico , Surdez/prevenção & controle , Perda Auditiva/diagnóstico , Perda Auditiva/prevenção & controle , Surdez/genética , Orelha Interna , Feminino , Aconselhamento Genético , Perda Auditiva/genética , Humanos , Gravidez , Diagnóstico Pré-Natal
12.
Neural Plast ; 2018: 7272308, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849566

RESUMO

Genetic hearing impairment is highly heterogeneous. In this study, targeted next-generation sequencing (NGS) in two Chinese Han families identified a novel p.G141R homozygous mutation in ILDR1 as the genetic cause of the deafness. Consistent with the recessive inheritance, cosegregation of the p.G141R variant with the hearing loss was confirmed in members of both families by PCR amplification and Sanger sequencing. SNP genotyping analysis suggested that those two families were not closely related. Our study showed that targeted NGS is an effective tool for diagnosis of genetic deafness and that p.G141R in ILDR1 may be a relatively frequent mutation for DFNB42 in Chinese Hans.


Assuntos
Surdez/genética , Predisposição Genética para Doença , Perda Auditiva Neurossensorial/genética , Receptores de Superfície Celular/genética , Povo Asiático/genética , China , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Linhagem , Polimorfismo de Nucleotídeo Único
13.
Neural Plast ; 2018: 1970150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30154835

RESUMO

Microglial cells are involved in surveillance and cleaning of the central nervous system. Recently, microglial-like cells (MLC) have been found in an adult cochlea and investigated for their role in cochlear inflammation. The presence and potential roles of MLCs during the development of the cochlea, however, remain unclear. In this study, immunostaining was performed using the MLC-specific marker IBA1 to characterize the presence, distribution, and morphology of MLCs in the developing cochlea. From P0 to P14, MLCs were present in a variety of cochlear regions including the modiolus, spiral lamina, spiral ganglion, spiral ligament, and the organ of Corti. Interestingly, the overall number of MLCs in a mouse cochlea steadily increased since P0, peaks at P5, then gradually decreased from P5 to P14. In the spiral ligament, the distribution of the MLCs trends to shift from the type I/II fibrocyte-rich regions to the type III/IV fibrocyte-rich regions during the course of cochlear development, accompanied by the morphological changes of MLCs from the amoeboid, activated form to the ramified, quiescent form. Our results suggested that MLCs experience drastic morphological and distributional changes during postnatal cochlear development, which may play a role in the maturing and remodeling of the cochlea.


Assuntos
Cóclea/crescimento & desenvolvimento , Cóclea/ultraestrutura , Microglia/fisiologia , Microglia/ultraestrutura , Animais , Animais Recém-Nascidos , Camundongos , Camundongos Endogâmicos C57BL
14.
Sci Total Environ ; 952: 175845, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39209172

RESUMO

Vegetation change in the Tibetan Plateau (TP) is a crucial indicator of climate change in alpine regions. Previous studies have reported an overall greening trend in the vegetation structure across the TP, especially in its northeastern part, in response to a warming climate. However, variations in the vegetation function and the possible drivers remain poorly understood. Considering the optimal temperature for plants in TP is usually higher than the current temperature, our hypothesis is the function and structure of alpine vegetation have changed synchronously over past few decades. To test this hypothesis, we analyzed satellite-observed solar-induced chlorophyll fluorescence (SIF) and leaf area index (LAI) in the Yellow River source (YRS) region in the northeastern TP to quantify the long-term trends in vegetation functional and structural states, respectively. The results suggest that from 1982 to 2018, SIF increased significantly in 77.71 % of the YRS area, resulting in a significant upward trend of 0.52 × 10-3 mW m-2 nm-1 sr-1 yr-1 (p < 0.001) for the regional-mean SIF. This represents a 16.1 % increase in SIF, which is close in magnitude to the increase in LAI over the same period. The synchronous changes between vegetation function and structure suggest that improved greenness corresponds to a similar level of change in carbon uptake across YRS. Additionally, we used a multiple regression approach to quantify the contribution of climatic factors to SIF changes in YRS. Our analyses show that the increases in SIF were primarily driven by rising temperatures. Spatially, temperature dominated SIF changes in most parts of YRS, except for certain dry parts in the northern and western YRS, where precipitation had a greater impact. Our results are crucial for a comprehensive understanding of climate regulations on vegetation structure and function in high-elevation regions.

15.
Int J Biol Macromol ; 259(Pt 2): 129208, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38185298

RESUMO

The Staphylococcus aureus clumping factor A (ClfA) is a fibrinogen (Fg) binding protein that plays an important role in the clumping of S. aureus in blood plasma. The current anti-infective approaches targeting ClfA are mainly based on monoclonal antibodies but showed less impressive efficacy for clinical applications. Nanobodies offer advantages in enhanced tissue penetration and a propensity to bind small epitopes. However, there is no report on generating specific nanobodies for ClfA. Here, we constructed a synthetic nanobody library based on yeast surface display to isolate nanobodies against the Fg binding domain ClfA221-550. We firstly obtained a primary nanobody directed to ClfA221-550, and then employed error-prone mutagenesis to enhance its binding affinity. Finally, 18 variants were isolated with high affinities (EC50, 1.1 ± 0.1 nM to 4.8 ± 0.3 nM), in which CNb1 presented the highest inhibition efficiency in the adhesion of S. aureus to fibrinogen. Moreover, structural simulation analysis indicated that the epitope for CNb1 partially overlapped with the binding sites for fibrinogen, thus inhibiting ClfA binding to Fg. Overall, these results indicated that the specific nanobodies generated here could prevent the adhesion of S. aureus to fibrinogen, suggesting their potential capacities in the control of S. aureus infections.


Assuntos
Anticorpos de Domínio Único , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Saccharomyces cerevisiae/metabolismo , Anticorpos de Domínio Único/metabolismo , Sítios de Ligação , Fibrinogênio/metabolismo
16.
Cell Death Dis ; 15(6): 409, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862475

RESUMO

Low glucose is a common microenvironment for rapidly growing solid tumors, which has developed multiple approaches to survive under glucose deprivation. However, the specific regulatory mechanism remains largely elusive. In this study, we demonstrate that glucose deprivation, while not amino acid or serum starvation, transactivates the expression of DCAF1. This enhances the K48-linked polyubiquitination and proteasome-dependent degradation of Rheb, inhibits mTORC1 activity, induces autophagy, and facilitates cancer cell survival under glucose deprivation conditions. This study identified DCAF1 as a new cellular glucose sensor and uncovered new insights into mechanism of DCAF1-mediated inactivation of Rheb-mTORC1 pathway for promoting cancer cell survival in response to glucose deprivation.


Assuntos
Sobrevivência Celular , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteína Enriquecida em Homólogo de Ras do Encéfalo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Glucose/metabolismo , Linhagem Celular Tumoral , Autofagia , Ubiquitinação , Transdução de Sinais , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Células HEK293 , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética
17.
Heliyon ; 10(1): e23479, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38205310

RESUMO

Objectives: The purpose of this study is to describe the current situation and forecast the trends of co-infection between the human immunodeficiency virus (HIV) and drug-susceptible tuberculosis (DS-TB) in different countries, across various age groups and genders. Methods: We obtained data on the number of cases, age-standardized incidence rate, age-standardized prevalence rate, age-standardized rate of disability-adjusted life years (DALYs), and age-standardized death rate from the Global Burden of Disease (GBD) 2019 database. These data were used to describe the distribution and burden of co-infection between the human immunodeficiency virus (HIV) and DS-TB in different regions, genders, and age groups. We employed joinpoint regression analysis to analyze the temporal trends from 1990 to 2019. Additionally, an age-period-cohort model was established to forecast the future trends of co-infection up to 2040. Results: The prevalence and burden of co-infection varied across different age groups and genders. The territories with the higher disease burden were distributed in some Asian and African countries. In terms of temporal trends, the age-standardized incidence rate and age-standardized prevalence rate of HIV and DS-TB co-infection exhibited an overall increasing trend from 1990 to 2019, and the prediction indicated a slow downward trend from 2019 to 2040. Conclusions: The co-infection of HIV and DS-TB posed a grave threat to public health and economic development. What's more, there existed a significant disparity between the actual state of co-infection and the desired goals for prevention and control.

18.
Front Bioeng Biotechnol ; 11: 1186897, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251570

RESUMO

Objective: The purpose of this study was to investigate whether bacteriochlorophyll a (BCA) could be used as a potential diagnostic factor in near-infrared fluorescence (NIRF) imaging and in mediating sonodynamic antitumor effect. Methods: The UV spectrum and fluorescence spectra of bacteriochlorophyll a were measured. The IVIS Lumina imaging system was used to observe the fluorescence imaging of bacteriochlorophyll a. 9,10-Dimethylanthracene (DMA) reagent was used as a singlet oxygen sensor to detect singlet oxygen produced by bacteriochlorophyll a. LLC cells of mouse lung adenocarcinoma were selected as experimental subjects. Flow cytometry was used to detect the optimal uptake time of bacteriochlorophyll a in LLC cells. A laser confocal microscope was used to observe the binding of bacteriochlorophyll a to cells. The cell survival rate of each experimental group was detected by the CCK-8 method to detect the cytotoxicity of bacteriochlorophyll a. The effect of BCA-mediated sonodynamic therapy (SDT) on tumor cells was detected by the calcein acetoxymethyl ester/propidium iodide (CAM/PI) double staining method. 2,7-Dichlorodihydrofluorescein-diacetate (DCFH-DA) was used as the staining agent to evaluate and analyze intracellular reactive oxygen species (ROS) levels by fluorescence microscopy and flow cytometry (FCM). A confocal laser scanning microscope (CLSM) was used to observe the localization in the organelles of bacteriochlorophyll a. The IVIS Lumina imaging system was used to observe the fluorescence imaging of BCA in vitro. Results: Bacteriochlorophyll a-mediated SDT significantly increased cytotoxicity to LLC cells compared to other treatments, such as ultrasound (US) only, bacteriochlorophyll a only, and sham therapy. The CLSM observed bacteriochlorophyll a aggregation around the cell membrane and cytoplasm. FCM analysis and fluorescence microscopy showed that bacteriochlorophyll a-mediated SDT in LLC cells significantly inhibited cell growth and caused an obvious increase in intracellular ROS levels, and its fluorescence imaging function suggests that it can be a potential diagnostic factor. Conclusion: The results showed that bacteriochlorophyll a possesses good sonosensitivity and fluorescence imaging function. It can be effectively internalized in LLC cells, and bacteriochlorophyll a-mediated SDT is associated with ROS generation. This suggests that bacteriochlorophyll a can be used as a new type of sound sensitizer, and the bacteriochlorophyll a-mediated sonodynamic effect may be a potential treatment for lung cancer.

19.
Front Public Health ; 11: 1282051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035283

RESUMO

Objective: This study aims to review the blood routine and biochemical indicators of the plateau population for three consecutive years, and analyze the impact of the plateau on these blood indicators of the Tibetan population and the Han immigrant population. Method: These parameters were extracted from the Laboratory Department of Ali District People's Hospital in Tibet from January 2019 to December 2021, including blood routine, liver and kidney function, blood lipids, myocardial enzyme spectrum, and rheumatic factor indicators. Changes in these parameters were analyzed over 3 consecutive years according to inclusion and exclusion criteria. Result: A total of 114 Tibetans and 93 Hans participated in the study. These parameters were significantly different between Tibetan and Han populations. Red blood cells (RBC), hemoglobin (HGB), hematocrit (HCT), mean hemoglobin content (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cells (WBC), lymphocytes (LYMPH) and monocytes (MONO) were significantly higher in Hans than Tibetans (p < 0.05). Biochemically, total bilirubin (TBIL), direct bilirubin (DBIL), albumin (ALB), urea nitrogen (Urea), creatinine (Cr), uric acid (UA), glucose (GLU), triglycerides (TG) and creatine kinase isoenzyme (CKMB) were significantly higher in Hans than Tibetans; aspartate aminotransferase (AST), glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), antistreptolysin (ASO), and C-reactive protein (CRP) were significantly higher in Tibetans than Hans (p < 0.05). There were no obvious continuous upward or downward trend of the parameters for 3 consecutive years. Conclusion: In high-altitude areas, Han immigrants have long-term stress changes compared with Tibetans. The main differences are reflected in the blood system, liver and kidney functions, etc., which provide basic data for further research on the health status of plateau populations.


Assuntos
Altitude , Hemoglobinas , Humanos , Tibet/epidemiologia , Estudos Longitudinais , Hemoglobinas/análise , Bilirrubina , Ureia
20.
Eur J Med Chem ; 246: 114955, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36459757

RESUMO

A series of novel ß-carboline derivatives was designed, synthesized and evaluated as potential anticancer agents. Among them, compound 6g showed the most potent antiproliferative activity against the 786-0, HT-29 and 22RV1 cell lines with IC50 values of 2.71, 2.02, and 3.86 µM, respectively. The antitumor efficiency of compound 6gin vivo was also evaluated, and the results revealed that compound 6g significantly suppressed tumor development and reduced tumor weight in a mouse colorectal cancer homograft model. Further investigation on mechanisms of action demonstrated that compound 6g inhibited HCT116 cell growth by stimulating the ATG5/ATG7-dependent autophagic pathway. These molecules might be served as candidates for further development of colorectal cancer therapy agent.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Animais , Camundongos , Relação Estrutura-Atividade , Proliferação de Células , Carbolinas , Células HT29 , Autofagia , Neoplasias Colorretais/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Estrutura Molecular
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