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1.
Biomaterials ; 312: 122733, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39106819

RESUMEN

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) demonstrates unique characteristics in anticancer therapies as it selectively induces apoptosis in cancer cells. However, most cancer cells are TRAIL-resistant. Odanacatib (ODN), a cathepsin K inhibitor, is considered a novel sensitizer for cancer treatment. Combination therapy between TRAIL and sensitizers is considered a potent platform that improves TRAIL-based anticancer therapies beyond TRAIL monotherapy. Herein, we developed ODN loaded poly(lactic-co-glycolic) nanoparticles conjugated to GST-TRAIL (TRAIL-ODN-PLGA-NPs) to target and treat TRAIL-resistant cancer. TRAIL-ODN-PLGA-NPs demonstrated a significant increase in cellular uptake via death receptors (DR5 and DR4) on surface of cancer cells. TRAIL-ODN-PLGA-NPs exposure destroyed more TRAIL-resistant cells compared to a single treatment with free drugs. The released ODN decreased the Raptor protein, thereby increasing damage to mitochondria by elevating reactive oxygen species (ROS) generation. Additionally, Bim protein stabilization improved TRAIL-resistant cell sensitization to TRAIL-induced apoptosis. The in vivo biodistribution study revealed that TRAIL-ODN-PLGA-NPs demonstrated high location and retention in tumor sites via the intravenous route. Furthermore, TRAIL-ODN-PLGA-NPs significantly inhibited xenograft tumor models of TRAIL-resistant Caki-1 and TRAIL-sensitive MDA-MB-231 cells.The inhibition was associated with apoptosis activation, Raptor protein stabilizing Bim protein downregulation, Bax accumulation, and mitochondrial ROS generation elevation. Additionally, TRAIL-ODN-PLGA-NPs affected the tumor microenvironment by increasing tumor necrosis factor-α and reducing interleukin-6. In conclusion, we evealed that our formulation demonstrated synergistic effects against TRAIL compared with the combination of free drug in vitro and in vivo models. Therefore, TRAIL-ODN-PLGA-NPs may be a novel candidate for TRAIL-induced apoptosis in cancer treatment.


Asunto(s)
Antineoplásicos , Compuestos de Bifenilo , Resistencia a Antineoplásicos , Nanopartículas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ligando Inductor de Apoptosis Relacionado con TNF , Animales , Femenino , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Compuestos de Bifenilo/uso terapéutico , Compuestos de Bifenilo/farmacología , Compuestos de Bifenilo/química , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Especies Reactivas de Oxígeno/metabolismo , Distribución Tisular , Ligando Inductor de Apoptosis Relacionado con TNF/uso terapéutico , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología
2.
Clin Chim Acta ; 564: 119907, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39127297

RESUMEN

BACKGROUND: Various biomarkers reportedly predict persistent acute kidney injury (AKI) despite their varying predictive performance across clinical trials. This study aims to compare the accuracy of various biomarkers in predicting persistent AKI in different populations and regions. METHODS: In this meta-analysis, we searched for urinary C-C motif chemokine ligand 14 (CCL14), Tissue inhibitor of metalloproteinase-2&insulin-like growth factor-binding protein-7 (TIMP-2&IGFBP7), Neutrophil Gelatinase-Associated Lipocalin (NGAL), plasma Cystatin C (pCysC), Soluble urokinase plasminogen activator receptor (suPAR), Proenkephalin (PenK) and urinary dickkopf-3:urinary creatinine (uDKK3:uCr) from various databases including Medline, PubMed, Embase, and Cochrane. This was geared towards predicting persistent AKI in adults (>18 years). Hierarchically summarized subject work characteristic curves (HSROC) and diagnostic odds ratio (DOR) values were used to summarize the diagnostic accuracy of the biomarkers. Further, meta-regression and subgroup analyses were carried out to identify sources of heterogeneity as well as evaluate the best predictive biomarkers in different populations and regions. RESULTS: We screened 31 studies from 2,356 studies and assessed the diagnostic value of 7 biomarkers for persistent AKI. Overall, CCL14 had the best diagnostic efficacy with an AUC of 0.79 (95 % CI 0.75-0.82), whereas TIMP-2 & IGFBP7, NGAL, and pCysC had diagnostic efficacy of 0.75 (95 % CI 0.71-0.79),0.71 (95 % CI 0.67-0.75), and 0.7007, respectively. Due to a limited number of studies, PenK, uDKK3:uCr, and suPAR were not subjected to meta-analysis; however, relevant literature reported diagnostic efficacy above 0.70. Subgroup analyses based on population, region, biomarker detection time, AKI onset time, and AKI duration revealed that in the intensive care unit (ICU) population, the AUC of CCL14 was 0.8070, the AUC of TIMP-2 & IGFBP7 was 0.726, the AUC of pCysC was 0.72, and the AUC of NGAL was 0.7344; in the sepsis population, the AUC of CCL14 was 0.85, the AUC of TIMP-2&IGFBP7 was 0.7438, and the AUC of NGAL was 0.544; in the post-operative population, the AUC of CCL14 was 0.83-0.93, the AUC of TIMP-2&IGFBP7 was 0.71, and the AUC of pCysC was 0.683. Regional differences were observed in biomarker prediction of persistent kidney injury, with AUCs of 0.8558 for CCL14, 0.7563 for TIMP-2 & IGFBP7, and 0.7116 for NGAL in the Eurasian American population. In the sub-African population, TIMP-2 & IGFBP7 had AUCs of 0.7945, 0.7418 for CCL14, 0.7097 for NGAL, and 0.7007 for pCysC. for TIMP-2 & IGFBP7 was 0.7945, AUC for CCL14 was 0.7418, AUC for NGAL was 0.7097, and AUC for pCysC was 0.7007 in the sub-African population. Duration of biomarker detection, AKI onset, and AKI did not influence the optimal predictive performance of CCL14. Subgroup analysis and meta-regression of CCL14-related studies revealed that CCL14 is the most appropriate biomarker for predicting persistent stage 2-3 AKI, with heterogeneity stemming from sample size and AKI staging. CONCLUSION: This meta-analysis discovered CCL14 as the best biomarker to predict persistent AKI, specifically persistent stage 2-3 AKI.


Asunto(s)
Lesión Renal Aguda , Biomarcadores , Humanos , Biomarcadores/sangre , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/sangre , Lesión Renal Aguda/orina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/orina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre
3.
J Environ Sci (China) ; 147: 597-606, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39003074

RESUMEN

Harnessing bacteria for superoxide production in bioremediation holds immense promise, yet its practical application is hindered by slow production rates and the relatively weak redox potential of superoxide. This study delves into a cost-effective approach to amplify superoxide production using an Arthrobacter strain, a prevalent soil bacterial genus. Our research reveals that introducing a carbon source along with specific iron-binding ligands, including deferoxamine (DFO), diethylenetriamine pentaacetate (DTPA), citrate, and oxalate, robustly augments microbial superoxide generation. Moreover, our findings suggest that these iron-binding ligands play a pivotal role in converting superoxide into hydroxyl radicals by modulating the electron transfer rate between Fe(III)/Fe(II) and superoxide. Remarkably, among the tested ligands, only DTPA emerges as a potent promoter of this conversion process when complexed with Fe(III). We identify an optimal Fe(III) to DTPA ratio of approximately 1:1 for enhancing hydroxyl radical production within the Arthrobacter culture. This research underscores the efficacy of simultaneously introducing carbon sources and DTPA in facilitating superoxide production and its subsequent conversion to hydroxyl radicals, significantly elevating bioremediation performance. Furthermore, our study reveals that DTPA augments superoxide production in cultures of diverse soils, with various soil microorganisms beyond Arthrobacter identified as contributors to superoxide generation. This emphasizes the universal applicability of DTPA across multiple bacterial genera. In conclusion, our study introduces a promising methodology for enhancing microbial superoxide production and its conversion into hydroxyl radicals. These findings hold substantial implications for the deployment of microbial reactive oxygen species in bioremediation, offering innovative solutions for addressing environmental contamination challenges.


Asunto(s)
Arthrobacter , Biodegradación Ambiental , Radical Hidroxilo , Hierro , Superóxidos , Radical Hidroxilo/metabolismo , Superóxidos/metabolismo , Arthrobacter/metabolismo , Hierro/metabolismo , Ligandos , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Deferoxamina/metabolismo
4.
J Pathol ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39360360

RESUMEN

Hunner-type interstitial cystitis (HIC) is a chronic inflammatory disease of the urinary bladder with an unknown etiology. We conducted comprehensive immunogenomic profiling of bladder specimens obtained by biopsy and cystectomy from 37 patients with HIC. Next-generation RNA sequencing demonstrated abundant plasma cell infiltration with frequent light chain restriction in HIC-affected bladder tissue. Subsequent analysis of the B-cell receptor repertoire revealed spatial and temporal expansion of B-cell clones. The extent of B-cell clonal expansion was significantly correlated with the gene expression levels of TNFSF13 and TNFSF13B, which encode APRIL and BAFF, respectively. These findings indicate that APRIL and BAFF are the key regulators of clonal B-cell expansion in HIC and might serve as therapeutic targets in this debilitating disease. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

5.
Chem Biol Interact ; 403: 111260, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39357784

RESUMEN

Homocysteine (Hcy) is produced through methionine transmethylation. Elevated Hcy levels are termed Hyperhomocysteinemia (HHcy) and represent a risk factor for neurodegenerative conditions such as Alzheimer's disease. This study aimed to explore the impact of mild HHcy and the neuroprotective effects of ibuprofen and rivastigmine via immunohistochemical analysis of glial markers (Iba-1 and GFAP). Additionally, we assessed levels of vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), chemokine ligand 5 (CCL5/RANTES), CX3C chemokine ligand 1 (CX3CL1), and the NGF/p75NTR/tropomyosin kinase B (TrkB) pathway in the hippocampus of adult rats. Mild chronic HHcy was induced chemically in Wistar rats by subcutaneous administration of Hcy (4 mg/kg body weight) twice daily for 30 days. Rivastigmine (0.5 mg/kg) and ibuprofen (40 mg/kg) were administered intraperitoneally once daily. Results revealed elevated levels of CCL5/RANTES and reduced levels of VEGF, EGF, and TrkB in the hippocampus of HHcy-exposed rats. Rivastigmine mitigated the neurotoxic effects of HHcy by increasing TrkB and VEGF levels. Conversely, ibuprofen attenuated CCL5/RANTES levels against the neurotoxicity of HHcy, significantly reducing this chemokine's levels. HHcy-induced neurochemical impairment in the hippocampus may jeopardize neurogenesis, synapse formation, axonal transport, and inflammatory balance, leading to neurodegeneration. Treatments with rivastigmine and ibuprofen alleviated some of these detrimental effects. Reversing HHcy-induced damage through these compounds could serve as a potential neuroprotective strategy against brain damage.

6.
Microb Pathog ; 196: 106990, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39362288

RESUMEN

The rising demand for innovative antimicrobial solutions has shifted focus towards silver nanoparticles (AgNPs), especially those produced through eco-friendly methods. This study introduces a novel approach utilizing actinomycetes strains-Streptomyces albus, Micromonospora maris, and Arthrobacter crystallopoietes-to biosynthesize AgNPs with remarkable antibacterial properties. Through molecular characterization, we identified unique features of these nanoparticles, and computational modeling suggested significant ion-ligand interactions with proteins 6REV and 3K07. Our research highlights the promise of these biogenically synthesized nanoparticles in advancing biomedical applications. Actinomycetes were sourced and screened for their ability to produce metallic nanoparticles, revealing that among 35 samples, only six showed this capability. Notably, Streptomyces albus strain smmdk14 (OR685674), Micromonospora maris strain smmdk13 (OR685672), and Arthrobacter crystallopoietes strain smmdk12 (OR685674) were identified as effective silver nanoparticle producers. The synthesized nanoparticles demonstrated potent antibacterial activity against common pathogens including E. coli, Pseudomonas aeruginosa, Klebsiella spp., Enterococcus faecalis, Staphylococcus aureus, and Acinetobacter spp. The data obtained from color change observation, UV-visible spectrophotometry, Zeta potential, FTIR spectroscopy, and transmission electron microscopy (TEM) characterized AgNPs potentiality. The nanoparticles were spherical, with sizes ranging from 6.46 nm to 24.7 nm. Optimization of production conditions, comparison of antimicrobial effects with antibiotics, evaluation of potential toxicity, and assessment of wound-healing capabilities were also conducted. The biosynthesized AgNPs exhibited superior antibacterial properties compared to traditional antibiotics and significantly accelerated wound healing by approximately 66.4 % in fibroblast cell cultures. Additionally, computational analysis predicted interactions between various metal ions and specific amino acid residues in proteins 6REV and 3K07. Overall, this study demonstrates the successful creation of AgNPs with notable antibacterial and wound-healing properties, underscoring their potential for medical applications.

7.
J Comput Chem ; 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367774

RESUMEN

In protein-ligand docking, the score assigned to a protein-ligand complex is approximate. Especially, the internal energy of the ligand is difficult to compute precisely using a molecular mechanics based force-field, introducing significant noise in the rank-ordering of ligands. We propose an open-source protocol (https://github.com/UnixJunkie/MMO), using two quantum mechanics (QM) single point energy calculations, plus a Monte Carlo (Monte Carlo) based ligand minimization procedure in-between, to estimate ligand strain after docking. The MC simulation uses the ANI-2x (QM approximating) force field and is performed in the dihedral space. On some protein targets, using strain filtering after docking allows to significantly improve hit rates. We performed a structure-based virtual screening campaign on nine protein targets from the Laboratoire d'Innovation Thérapeutique-PubChem assays dataset using Cambridge crystallographic data centre genetic optimization for ligand docking. Then, docked ligands were submitted to the strain estimation protocol and the impact on hit rate was analyzed. As for docking, the method does not always work. However, if sufficient active and inactive molecules are known for a given protein target, its efficiency can be evaluated.

8.
Drug Discov Today ; : 104197, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39368697

RESUMEN

Cryptic sites can expand the space of druggable proteins, but the potential usefulness of such sites needs to be investigated before any major effort. Given that the binding pockets are not formed, the druggability of such sites is not well understood. The analysis of proteins and their ligands shows that cryptic sites that are formed primarily by the motion of side chains moving out of the pocket to enable ligand binding generally do not bind drug-sized molecules with sufficient potency. By contrast, sites that are formed by loop or hinge motion are potentially valuable drug targets. Arguments are provided to explain the underlying causes in terms of classical enzyme inhibition theory and the kinetics of side chain motion and ligand binding.

9.
J Hepatocell Carcinoma ; 11: 1823-1833, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39364434

RESUMEN

Purpose: To examine the relationship between lactate dehydrogenase (LDH) levels and soluble programmed cell death-ligand 1 (sPD-L1) levels in hepatocellular carcinoma (HCC) patients undergoing transarterial chemoembolization (TACE). Methods: A total of 83 hCC patients participated in this study. Patients were categorized into subgroups based on their alpha-fetoprotein (AFP) levels, presence or absence of extrahepatic metastasis, vascular invasion, Barcelona Clinic Liver Cancer (BCLC) stage, tumor response, tumor size, and number LDH and sPD-L1 levels were compared before and after TACE (3, 7, and 30 days post-TACE). Results: LDH and sPD-L1 levels were significantly higher at 3 and 7 days post-TACE than at baseline. Positive correlations were observed between changes in LDH levels and sPD-L1 levels at 3 and 7 days post-TACE. LDH levels were higher in patients with elevated AFP compared to those in the normal AFP group at 3 and 7 days post-TACE, in the stable disease (SD) group compared to complete response (CR) and partial response (PR) groups at 7 days post-TACE, and in those with tumor > 5 cm compared with those with tumor ≤ 5 cm at 3 and 7 days after TACE (all P < 0.05). sPD-L1 levels were higher in patients with vascular invasion than those without vascular invasion at 3 and 7 days post-TACE, in the SD group compared to CR and PR groups at 3 and 7 days post-TACE, and in those with tumor > 5 cm compared to those with tumor < 5 cm at 3 and 7 days after TACE (all P < 0.05). Conclusion: A positive correlation was found between LDH expression and sPD-L1 levels, suggesting LDH as a potential biomarker for assessing immune status in HCC patients following TACE.

10.
Proc Natl Acad Sci U S A ; 121(41): e2409097121, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39365813

RESUMEN

The only known peptide-gated ion channels-FaNaCs/WaNaCs and HyNaCs-belong to different clades of the DEG/ENaC family. FaNaCs are activated by the short neuropeptide FMRFamide, and HyNaCs by Hydra RFamides, which are not evolutionarily related to FMRFamide. The FMRFamide-binding site in FaNaCs was recently identified in a cleft atop the large extracellular domain. However, this cleft is not conserved in HyNaCs. Here, we combined molecular modeling and site-directed mutagenesis and identified a putative binding pocket for Hydra-RFamides in the extracellular domain of the heterotrimeric HyNaC2/3/5. This pocket localizes to only one of the three subunit interfaces, indicating that this trimeric ion channel binds a single peptide ligand. We engineered an unnatural amino acid at the putative binding pocket entrance, which allowed covalent tethering of Hydra RFamide to the channel, thereby trapping the channel in an open conformation. The identified pocket localizes to the same region as the acidic pocket of acid-sensing ion channels (ASICs), which binds peptide ligands. The pocket in HyNaCs is less acidic, and both electrostatic and hydrophobic interactions contribute to peptide binding. Collectively, our results reveal a conserved ligand-binding pocket in HyNaCs and ASICs and indicate independent evolution of peptide-binding cavities in the two subgroups of peptide-gated ion channels.


Asunto(s)
Canales Iónicos Sensibles al Ácido , Animales , Sitios de Unión , Canales Iónicos Sensibles al Ácido/metabolismo , Canales Iónicos Sensibles al Ácido/genética , Canales Iónicos Sensibles al Ácido/química , Hydra/metabolismo , Hydra/genética , Péptidos/metabolismo , Péptidos/química , Modelos Moleculares , FMRFamida/metabolismo , Unión Proteica , Secuencia de Aminoácidos , Anémonas de Mar/metabolismo , Anémonas de Mar/genética , Mutagénesis Sitio-Dirigida , Neuropéptidos/metabolismo , Neuropéptidos/genética , Neuropéptidos/química
11.
J Exp Clin Cancer Res ; 43(1): 275, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39350280

RESUMEN

BACKGROUND: The vast majority of pancreatic cancers have been shown to be insensitive to single-agent immunotherapy. Exploring the mechanisms of immune resistance and implementing combination therapeutic strategies are crucial for PDAC patients to derive benefits from immunotherapy. Deletion of BAP1 occurs in approximately 27% of PDAC patients and is significantly correlated with poor prognosis, but the mechanism how BAP1-deletion compromises survival of patients with PDAC remain a puzzle. METHODS: Bap1 knock-out KPC (KrasG12D/+; LSLTrp53R172H/+; Pdx-1-Cre) mice and control KPC mice, syngeneic xenograft models were applied to analysis the correlation between BAP1 and immune therapy response in PDAC. Immunoprecipitation, RT-qPCR, luciferase and transcriptome analysis were combined to revealing potential mechanisms. Syngeneic xenograft models and flow cytometry were constructed to examine the efficacy of the inhibitor of SIRT1 and its synergistic effect with anti-PD-1 therapy. RESULT: The deletion of BAP1 contributes to the resistance to immunotherapy in PDAC, which is attributable to BAP1's suppression of the transcriptional activity of HSF1. Specifically, BAP1 competes with SIRT1 for binding to the K80 acetylated HSF1. The BAP1-HSF1 interaction preserves the acetylation of HSF1-K80 and promotes HSF1-HSP70 interaction, facilitating HSF1 oligomerization and detachment from the chromatin. Furthermore, we demonstrate that the targeted inhibition of SIRT1 reverses the immune insensitivity in BAP1 deficient PDAC mouse model. CONCLUSION: Our study elucidates an unrevealed mechanism by which BAP1 regulates immune therapy response in PDAC via HSF1 inhibition, and providing promising therapeutic strategies to address immune insensitivity in BAP1-deficient PDAC.


Asunto(s)
Neoplasias Pancreáticas , Proteínas Supresoras de Tumor , Ubiquitina Tiolesterasa , Animales , Ratones , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/metabolismo , Humanos , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Factores de Transcripción del Choque Térmico/metabolismo , Factores de Transcripción del Choque Térmico/genética , Línea Celular Tumoral , Ratones Noqueados , Inmunoterapia/métodos
12.
Artículo en Inglés | MEDLINE | ID: mdl-39361523

RESUMEN

Osteosarcoma (OS) is a lethal malignant orthotopic bone tumor that primarily affects children and adolescents. Biomimetic nanocarriers have attracted wide attention as a new strategy for delivering chemotherapy agents to the OS. However, challenges such as rapid clearance and limited targeting hinder the effectiveness of OS chemotherapy. In this study, we designed reactive oxygen species (ROS)-responsive nanoparticles (NPs) coated with an interleukin (IL)11-engineered macrophage membrane (MM). The camouflage by MMs prevents clearance of IL-11-engineered MM-coated NPs loaded with doxorubicin (IL-11/MM@NPs/Dox) by the immune system. Moreover, the macrophage membrane combined with surface-expressed IL-11 not only directed IL-11/MM@NPs/Dox to OS tissues but also selectively identified IL-11 receptor alpha (IL-11Rα)-enriched OS cells. Within these cells, elevated levels of ROS triggered the controlled release of Dox from the ROS-responsive NPs. The synergistic modification of targeted ligand conjugation and cell membrane coating on the ROS-responsive NPs enhanced drug availability and reduced toxic side effects, thereby boosting the efficacy of OS chemotherapy. In summary, our findings suggest that IL-11/MM@NPs/Dox represents a promising approach to improving OS chemotherapy efficacy while ensuring excellent biocompatibility.

13.
Proc Natl Acad Sci U S A ; 121(41): e2400298121, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39361640

RESUMEN

Somatostatin receptors (SSTRs) exert critical biological functions such as negatively regulating hormone release and cell proliferation, making them popular targets for developing therapeutics to treat endocrine disorders, especially neuroendocrine tumors. Although several panagonists mimicking the endogenous ligand somatostatin are available, the development of more effective and safer somatostatinergic therapies is limited due to a lack of molecular understanding of the ligand recognition and regulation of divergent SSTR subtypes. Here, we report four cryoelectron microscopy structures of Gi-coupled SSTR1 and SSTR3 activated by distinct agonists, including the FDA-approved panagonist pasireotide as well as their selective small molecule agonists L-797591 and L-796778. Our structures reveal a conserved recognition pattern of pasireotide in SSTRs attributed to the binding with a conserved extended binding pocket, distinct from SST14, octreotide, and lanreotide. Together with mutagenesis analyses, our structures further reveal the dynamic feature of ligand binding pockets in SSTR1 and SSTR3 to accommodate divergent agonists, the key determinants of ligand selectivity lying across the orthosteric pocket of different SSTR subtypes, as well as the molecular mechanism underlying diversity and conservation of receptor activation. Our work provides a framework for rational design of subtype-selective SSTR ligands and may facilitate drug development efforts targeting SSTRs with improved therapeutic efficacy and reduced side effects.


Asunto(s)
Microscopía por Crioelectrón , Receptores de Somatostatina , Somatostatina , Receptores de Somatostatina/metabolismo , Receptores de Somatostatina/química , Receptores de Somatostatina/agonistas , Humanos , Ligandos , Somatostatina/metabolismo , Somatostatina/análogos & derivados , Somatostatina/química , Sitios de Unión , Unión Proteica , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/metabolismo
14.
J Mol Graph Model ; 133: 108872, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39362060

RESUMEN

Human fatty acid-binding proteins (FABPs) are involved in many aspects of lipid metabolism, such as the uptake, transport, and storage of lipophilic molecules, as well as cellular functions. Understanding how FABPs recognize fatty acids (FAs) is crucial for identifying FABP function and applications, such as in inhibitor design or biomarker development. The recently developed AlphaFold3 (AF3) demonstrates significantly higher accuracy than other prediction tools, particularly in predicting protein-ligand interactions with state-of-the-art docking tools. Studies on whether AF3 can be used to identify the FAs of FABP are lacking. To assess the accuracy of FA docking to FABPs using AF3, models of FA docked into FABP generated using AF3 were compared with experimentally determined FA-bound FABP structures. FA ligands in AF3 structures docked reliably into the FA-binding pocket of FABPs; however, the detailed binding configuration of most FA ligands docked into FABPs and the interaction between FA and FABP determined using AF3 and experimentally differed. These results will aid in understanding FA docking to FABPs and other FA-binding proteins using AF3.

15.
J Comput Biol ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39364612

RESUMEN

D-peptides, the mirror image of canonical L-peptides, offer numerous biological advantages that make them effective therapeutics. This article details how to use DexDesign, the newest OSPREY-based algorithm, for designing these D-peptides de novo. OSPREY physics-based models precisely mimic energy-equivariant reflection operations, enabling the generation of D-peptide scaffolds from L-peptide templates. Due to the scarcity of D-peptide:L-protein structural data, DexDesign calls a geometric hashing algorithm, Method of Accelerated Search for Tertiary Ensemble Representatives, as a subroutine to produce a synthetic structural dataset. DexDesign enables mixed-chirality designs with a new user interface and also reduces the conformation and sequence search space using three new design techniques: Minimum Flexible Set, Inverse Alanine Scanning, and K*-based Mutational Scanning.

16.
Artículo en Inglés | MEDLINE | ID: mdl-39364618

RESUMEN

Interleukin-4 (IL-4) controls cell growth and immune system regulation in tumorigenesis and can inhibit the growth of colon cancer cell lines, but the possible mechanism is unclear. In this study, we investigated the possible mechanism of IL-4 in colorectal cancer (CRC) through in vitro experiments. CRC cells received treatment with IL-4 (50 ng/mL), investigating the suppressor of cytokine signaling 1 (SOCS1)-related mechanism underlying the role of IL-4 in the progression and immunosuppression of CRC. The malignant processes of CRC cells and CD8+T cell-mediated immune response in CRC cells were determined by CCK-8, Transwell, wound healing, and flow cytometry assays. Programmed death ligand 1 (PD-L1), SOCS1 expressions, and c-Jun N-terminal kinase (JNK) activation in CRC cells were analyzed by quantitative reverse transcription polymerase chain reaction and/or Western blot. IL-4 repressed the malignant processes, yet promoted the apoptosis of CRC cells. Besides, IL-4 downregulated PD-L1 level, upregulated SOCS1 level, and restrained JNK activation in CRC cells, while enhancing CRC cell-killing effect of CD8+T cells. IL-4-induced effects on the aforementioned malignant processes of CRC cells and the killing effect of CD8+T cells toward CRC cells were all reversed when SOCS1 was knocked down in the CRC cells. IL-4 downregulates PD-L1 level via SOCS1 upregulation-induced JNK deactivation to enhance antitumor immunity in in vitro CRC. The study provides a theoretical basis for the clinical application of IL-4 in antitumor immunity in CRC.

17.
Int J Mol Med ; 54(6)2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39364750

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a particularly aggressive form of cancer with high mortality. In the present study, a novel 8­hydroxyquinoline derivative (91b1) was investigated for its anticancer activities in ESCC along with its associated mechanisms. The in vitro cytotoxic effect of 91b1 were evaluated across five ESCC cell lines using MTS assay, with cisplatin serving as a comparative standard. Changes in gene expression profile were identified by cDNA microarray and further validated by qualitative PCR and immunostaining. Additionally, protein levels of the most notably downregulated target in archival ESCC samples were also studied. 91b1 demonstrated comparable anticancer effect with cisplatin. Notably, chemokine ligand 5 (Ccl5) was identified as the most substantially downregulated gene, with its suppression at both mRNA and protein expression in ESCC cells, exhibiting a dose­dependent manner. The recombinant human protein of CCL5 enhanced the invasion of ESCC cells using the Transwell assay. The upregulation of CCL5 protein was also detected in 50% of ESCC cell lines. CCL5 was also overexpressed in 76.9% of ESCC specimens. The overall results indicated that 91b1 could effectively induce anticancer effect on ESCC cells through downregulating CCL5 expression with suppression of tumor invasion. Overall, these findings suggested that 91b1 effectively inhibited ESCC cell proliferation and tumor invasion by downregulating CCL5 expression, highlighting its potential as a therapeutic agent for ESCC treatment.


Asunto(s)
Quimiocina CCL5 , Regulación hacia Abajo , Neoplasias Esofágicas , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/genética , Línea Celular Tumoral , Quimiocina CCL5/metabolismo , Quimiocina CCL5/genética , Regulación hacia Abajo/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Invasividad Neoplásica , Oxiquinolina/farmacología , Oxiquinolina/química , Oxiquinolina/análogos & derivados , Antineoplásicos/farmacología , Antineoplásicos/química , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Proliferación Celular/efectos de los fármacos , Masculino , Femenino , Movimiento Celular/efectos de los fármacos , Cisplatino/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genética
18.
ChemSusChem ; : e202401875, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354813

RESUMEN

The combination of the quantum confinement effect of quantum dots (QDs) and unique photoelectric properties of perovskite semiconductors make perovskite quantum dots (PQDs) a promising candidate for photoelectric devices. To truly unlock their potential, a deep understanding of structure-property relationship is paramount. Among the various factors influencing this relationship, the role of surface ligands cannot be overstated. The polarity, conductivity, stability, and interaction effects of these ligands with QD surfaces create complicated ligand-QDs relationships, which greatly influences the successful synthesis of QDs. In essence, the surface chemistry of ligands serves as a critical determinant in shaping the properties of both the resulting QDs and QD-based devices. To address this, our paper introduces an innovative approach to studying ligands, utilizing their inherent functional groups as a classification criterion. It is begun by discussing the types of surface defects of PQDs and the functional groups used for passivation, emphasizing the importance of analyzing ligands based on their functional groups. Then the passivation mechanisms of ligands with various functional groups and their impact on enhancing QD performance are delved into. Ultimately, this paper summarizes and offers several design principles and rules for PQDs surface ligands that can be applied in most scenarios.

19.
World J Gastroenterol ; 30(36): 4031-4035, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39351252

RESUMEN

In recent years, with the extensive application of immunotherapy in clinical practice, it has achieved encouraging therapeutic effects. While enhancing clinical efficacy, however, it can also cause autoimmune damage, triggering immune-related adverse events (irAEs). Reports of immunotherapy-induced gastritis have been increasing annually, but due to its atypical clinical symptoms, early diag-nosis poses a certain challenge. Furthermore, it can lead to severe complications such as gastric bleeding, elevating the risk of adverse outcomes for solid tumor patients if immunotherapy is interrupted. Therefore, gaining a thorough under-standing of the pathogenesis, clinical manifestations, diagnostic criteria, and treatment of immune-related gastritis is of utmost importance for early identification, diagnosis, and treatment. Additionally, the treatment of immune-related gastritis should be personalized according to the specific condition of each patient. For patients with grade 2-3 irAEs, restarting immune checkpoint inhibitors (ICIs) therapy may be considered when symptoms subside to grade 0-1. When restarting ICIs therapy, it is often recommended to use different types of ICIs. For grade 4 irAEs, permanent discontinuation of the medication is necessary.


Asunto(s)
Gastritis , Inhibidores de Puntos de Control Inmunológico , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Gastritis/inmunología , Gastritis/inducido químicamente , Gastritis/diagnóstico , Inmunoterapia/efectos adversos , Inmunoterapia/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología
20.
Chembiochem ; : e202400441, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39352839

RESUMEN

Original covalent probes with an N-acyl-N-alkyl sulfonamide cleavable linker were developed to target a broad set of human Matrix Metalloproteases (MMPs). The electrophilicity of this cleavable linker was modulated to improve the selectivity of the probes as well as reduce their unspecific reactivity in complex biological matrices. We first demonstrated that targeting the S3 subsite of MMPs enables access to broad-spectrum affinity-based probes that exclusively react with the active version of these proteases. The probes were further assessed in proteomes of varying complexity, where human MMP-13 was artificially introduced at known concentration and the resulting labeled MMP was imaged by in-gel fluorescence imaging. We showed that the less reactive probe was still able to covalently modify MMP-13 while exhibiting reduced off-target unspecific reactivity. This study clearly demonstrated the importance of finely controlling the reactivity of the NASA warhead to improve the selectivity of covalent probes in complex biological systems.

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