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1.
Cell ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38843831

RESUMEN

Experimental studies on DNA transposable elements (TEs) have been limited in scale, leading to a lack of understanding of the factors influencing transposition activity, evolutionary dynamics, and application potential as genome engineering tools. We predicted 130 active DNA TEs from 102 metazoan genomes and evaluated their activity in human cells. We identified 40 active (integration-competent) TEs, surpassing the cumulative number (20) of TEs found previously. With this unified comparative data, we found that the Tc1/mariner superfamily exhibits elevated activity, potentially explaining their pervasive horizontal transfers. Further functional characterization of TEs revealed additional divergence in features such as insertion bias. Remarkably, in CAR-T therapy for hematological and solid tumors, Mariner2_AG (MAG), the most active DNA TE identified, largely outperformed two widely used vectors, the lentiviral vector and the TE-based vector SB100X. Overall, this study highlights the varied transposition features and evolutionary dynamics of DNA TEs and increases the TE toolbox diversity.

2.
Cancer Control ; 31: 10732748241251562, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716503

RESUMEN

BACKGROUND: Liquid biopsy, including the detection of circulating tumor cells (CTCs), has emerged as a promising tool for cancer diagnosis and monitoring. However, the prognostic value of CTCs in nasopharyngeal carcinoma (NPC) remains unclear due to the lack of phenotypic characterization. The expression of Excision Repair Cross-Complementation Group 1 (ERCC1) and CTCs epithelial-mesenchymal transition (EMT) have been associated with treatment efficacy. In this study, we aimed to evaluate the prognostic significance of ERCC1 expression on CTCs and their EMT subtypes before treatment in NPC. METHODS: We retrospectively analyzed 108 newly diagnosed locally advanced NPC patients who underwent CanPatrol™ CTC testing between November 2018 and November 2021. CTCs were counted and classified into epithelial, epithelial-mesenchymal hybrid, and mesenchymal subtypes. ERCC1 expression was divided into negative and positive groups. Clinical features and survival outcomes were analyzed. RESULTS: The positive rate of CTCs was 92.6% (100/108), with an ERCC1 positivity rate of 74% (74/100). Further analysis of the subtypes showed that positive ERCC1 on mesenchymal CTCs was associated with a later N stage (P = .01). Positive ERCC1 expression was associated with poor overall survival (OS; P = .039) and disease-free survival (DFS; P = .035). Further analysis of subtypes showed that the positive ERCC1 on mesenchymal-type CTCs was associated with poor OS (P = .012) and metastasis-free survival (MFS; P = .001). CONCLUSION: Our findings suggest that ERCC1 expression on CTCs may serve as a new prognostic marker for NPC patients. Evaluating CTCs subtypes may become an auxiliary tool for personalized and precise treatment.


BackgroundLiquid biopsy, including the detection of circulating tumor cells (CTCs), has emerged as a promising tool for cancer diagnosis and monitoring. However, the prognostic value of CTCs in nasopharyngeal carcinoma (NPC) remains unclear due to the lack of phenotypic characterization. The expression of Excision Repair Cross-Complementation Group 1 (ERCC1) and CTCs epithelial-mesenchymal transition (EMT) have been associated with treatment efficacy. In this study, we aimed to evaluate the prognostic significance of ERCC1 expression on CTCs and their EMT subtypes before treatment in NPC.MethodsWe retrospectively analyzed 108 newly diagnosed locally advanced NPC patients who underwent CanPatrol™ CTC testing between November 2018 and November 2021. CTCs were counted and classified into epithelial, epithelial-mesenchymal hybrid, and mesenchymal subtypes. ERCC1 expression was divided into negative and positive groups. Clinical features and survival outcomes were analyzed.ResultsThe positive rate of CTCs was 92.6% (100/108), with an ERCC1 positivity rate of 74% (74/100). Further analysis of the subtypes showed that positive ERCC1 on mesenchymal CTCs was associated with a later N stage (P = .01). Positive ERCC1 expression was associated with poor overall survival (OS; P = .039) and disease-free survival (DFS; P = .035). Further analysis of subtypes showed that the positive ERCC1 on mesenchymal-type CTCs was associated with poor OS (P = .012) and metastasis-free survival (MFS; P = .001).ConclusionOur findings suggest that ERCC1 expression on CTCs may serve as a new prognostic marker for NPC patients. Evaluating CTCs subtypes may become an auxiliary tool for personalized and precise treatment.


Asunto(s)
Proteínas de Unión al ADN , Endonucleasas , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patología , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/sangre , Carcinoma Nasofaríngeo/mortalidad , Carcinoma Nasofaríngeo/metabolismo , Masculino , Femenino , Pronóstico , Persona de Mediana Edad , Endonucleasas/metabolismo , Estudios Retrospectivos , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/sangre , Neoplasias Nasofaríngeas/mortalidad , Proteínas de Unión al ADN/metabolismo , Transición Epitelial-Mesenquimal/genética , Adulto , Biomarcadores de Tumor/metabolismo , Anciano , Reparación por Escisión
3.
ACS Chem Biol ; 19(4): 999-1010, 2024 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-38513196

RESUMEN

Nonreceptor tyrosine kinase c-Src plays a crucial role in cell signaling and contributes to tumor progression. However, the development of selective c-Src inhibitors turns out to be challenging. In our previous study, we performed posttranslational modification-inspired drug design (PTMI-DD) to provide a plausible way for designing selective kinase inhibitors. In this study, after identifying a unique pocket comprising a less conserved cysteine and an autophosphorylation site in c-Src as well as a promiscuous covalent inhibitor, chemical optimization was performed to obtain (R)-LW-Srci-8 with nearly 75-fold improved potency (IC50 = 35.83 ± 7.21 nM). Crystallographic studies revealed the critical C-F···C═O interactions that may contribute to tight binding. The kinact and Ki values validated the improved binding affinity and decreased warhead reactivity of (R)-LW-Srci-8 for c-Src. Notably, in vitro tyrosine kinase profiling and cellular activity-based protein profiling (ABPP) cooperatively indicated a specific inhibition of c-Src by (R)-LW-Srci-8. Intriguingly, (R)-LW-Srci-8 preferentially binds to inactive c-Src with unphosphorylated Y419 both in vitro and in cells, subsequently disrupting the autophosphorylation. Collectively, our study demonstrated the feasibility of developing selective kinase inhibitors by cotargeting a nucleophilic residue and a posttranslational modification site and providing a chemical probe for c-Src functional studies.


Asunto(s)
Proteína Tirosina Quinasa CSK , Inhibidores de Proteínas Quinasas , Humanos , Proteína Tirosina Quinasa CSK/antagonistas & inhibidores , Proteína Tirosina Quinasa CSK/metabolismo , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Transducción de Señal , Familia-src Quinasas
4.
Apoptosis ; 29(1-2): 243-266, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37670104

RESUMEN

A particular GTPase-activating protein called RACGAP1 is involved in apoptosis, proliferation, invasion, metastasis, and drug resistance in a variety of malignancies. Nevertheless, the role of RACGAP1 in pan-cancer was less studied, and its value of the expression and prognostic of nasopharyngeal carcinoma (NPC) has not been explored. Hence, the goal of this study was to investigate the oncogenic and immunological roles of RACGAP1 in various cancers and its potential value in NPC. We comprehensively analyzed RACGAP1 expression, prognostic value, function, methylation levels, relationship with immune cells, immune infiltration, and immunotherapy response in pan-cancer utilizing multiple databases. The results discovered that RACGAP1 expression was elevated in most cancers and suggested poor prognosis, which could be related to the involvement of RACGAP1 in various cancer-related pathways such as the cell cycle and correlated with RACGAP1 methylation levels, immune cell infiltration and reaction to immunotherapy, and chemoresistance. RACGAP1 could inhibit anti-tumor immunity and immunotherapy responses by fostering immune cell infiltration and cytotoxic T lymphocyte dysfunction. Significantly, we validated that RACGAP1 mRNA and protein were highly expressed in NPC. The Gene Expression Omnibus database revealed that elevated RACGAP1 expression was associated with shorter PFS in patients with NPC, and RACGAP1 potentially influenced cell cycle progression, DNA replication, metabolism, and immune-related pathways, resulting in the recurrence and metastasis of NPC. This study indicated that RACGAP1 could be a potential biomarker in pan-cancer and NPC.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Apoptosis/genética , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Neoplasias Nasofaríngeas/genética
5.
PeerJ ; 11: e16301, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37953778

RESUMEN

Background: Chronic kidney disease (CKD) is a significant global health issue characterized by progressive loss of kidney function. Renal interstitial fibrosis (TIF) is a common feature of CKD, but current treatments are seldom effective in reversing TIF. Nicotinamide N-methyltransferase (NNMT) has been found to increase in kidneys with TIF, but its role in renal fibrosis is unclear. Methods: Using mice with unilateral ureteral obstruction (UUO) and cultured renal interstitial fibroblast cells (NRK-49F) stimulated with transforming growth factor-ß1 (TGF-ß1), we investigated the function of NNMT in vivo and in vitro. Results: We performed single-cell transcriptome sequencing (scRNA-seq) on the kidneys of mice and found that NNMT increased mainly in fibroblasts of UUO mice compared to sham mice. Additionally, NNMT was positively correlated with the expression of renal fibrosis-related genes after UUO injury. Knocking down NNMT expression reduced fibroblast activation and was accompanied by an increase in DNA methylation of p53 and a decrease in its phosphorylation. Conclusions: Our findings suggest that chronic kidney injury leads to an accumulation of NNMT, which might decrease p53 methylation, and increase the expression and activity of p53. We propose that NNMT promotes fibroblast activation and renal fibrosis, making NNMT a novel target for preventing and treating renal fibrosis.


Asunto(s)
Nicotinamida N-Metiltransferasa , Insuficiencia Renal Crónica , Obstrucción Ureteral , Fibrosis , Riñón/metabolismo , Nicotinamida N-Metiltransferasa/genética , Insuficiencia Renal Crónica/genética , Proteína p53 Supresora de Tumor/metabolismo , Obstrucción Ureteral/genética , Animales , Ratones
6.
FASEB J ; 37(10): e23175, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37742293

RESUMEN

Many studies have highlighted the importance of moderate exercise. While it can attenuate diabetic kidney disease, its mechanism has remained unclear. The level of myokine irisin in plasma increases during exercise. We found that irisin was decreased in diabetic patients and was closely related to renal function, proteinuria, and podocyte autophagy injury. Muscle-specific overexpression of PGC-1α (mPGC-1α) in a mouse model is known to increase plasma irisin levels. The mPGC-1α mice were crossed with db/m mice to obtain db/db mPGC-1α+ mice in the present study. Compared to db/db mice without mPGC-1α, plasma irisin was increased, and albuminuria and glomerular pathological damage were both alleviated in db/db mPGC-1α+ mice. Impaired autophagy in podocytes was restored as well. Irisin inhibited the activation of the PI3K/AKT/mTOR signaling pathway in cultured human podocytes and improved damaged autophagy induced by high glucose levels. Then, db/db mice were treated with recombinant irisin, which had similar beneficial effects on the kidney as those in db/db mPGC-1α+ mice, with alleviated glomerular injury and albuminuria. Moreover, the autophagy in podocytes was also significantly restored. These results suggest that irisin secreted by skeletal muscles protects the kidney from diabetes mellitus damage. It also restores autophagy in podocytes by inhibiting the abnormal activation of the PI3K/AKT/mTOR signaling pathway. Thus, irisin may become a new drug for the prevention and treatment of diabetic nephropathy.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Podocitos , Humanos , Ratones , Animales , Podocitos/metabolismo , Nefropatías Diabéticas/metabolismo , Fibronectinas/metabolismo , Albuminuria/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Autofagia , Serina-Treonina Quinasas TOR/metabolismo , Diabetes Mellitus/metabolismo
7.
Front Nutr ; 10: 1243390, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37614742

RESUMEN

Dietary fibers (DFs) and their metabolites attract significant attention in research on health and disease, attributing to their effects on regulating metabolism, proliferation, inflammation, and immunity. When fermented by gut microbiota, DFs mainly produce short-chain fatty acids (SCFAs), such as acetic acid, propionic acid, and butyric acid. As the essential nutrients for intestinal epithelial cells, SCFAs maintain intestinal homeostasis and play essential roles in a wide range of biological functions. SCFAs have been found to inhibit histone deacetylase, activate G protein-coupled receptors, and modulate the immune response, which impacts cancer and anti-cancer treatment. Notably, while extensive studies have illuminated the roles of SCFAs in colorectal cancer development, progression, and treatment outcomes, limited evidence is available for other types of cancers. This restricts our understanding of the complex mechanisms and clinical applications of SCFAs in tumors outside the intestinal tract. In this study, we provide a comprehensive summary of the latest evidence on the roles and mechanisms of SCFAs, with a focus on butyric acid and propionic acid, derived from microbial fermentation of DFs in cancer. Additionally, we recapitulate the clinical applications of SCFAs in cancer treatments and offer our perspectives on the challenges, limitations, and prospects of utilizing SCFAs in cancer research and therapy.

8.
Artículo en Inglés | MEDLINE | ID: mdl-37498753

RESUMEN

OBJECTIVE: A brain-computer interface (BCI) can be used to translate neuronal activity into commands to control external devices. However, using noninvasive BCI to control a robotic arm for movements in three-dimensional (3D) environments and accomplish complicated daily tasks, such as grasping and drinking, remains a challenge. APPROACH: In this study, a shared robotic arm control system based on hybrid asynchronous BCI and computer vision was presented. The BCI model, which combines steady-state visual evoked potentials (SSVEPs) and blink-related electrooculography (EOG) signals, allows users to freely choose from fifteen commands in an asynchronous mode corresponding to robot actions in a 3D workspace and reach targets with a wide movement range, while computer vision can identify objects and assist a robotic arm in completing more precise tasks, such as grasping a target automatically. RESULTS: Ten subjects participated in the experiments and achieved an average accuracy of more than 92% and a high trajectory efficiency for robot movement. All subjects were able to perform the reach-grasp-drink tasks successfully using the proposed shared control method, with fewer error commands and shorter completion time than with direct BCI control. SIGNIFICANCE: Our results demonstrated the feasibility and efficiency of generating practical multidimensional control of an intuitive robotic arm by merging hybrid asynchronous BCI and computer vision-based recognition.


Asunto(s)
Interfaces Cerebro-Computador , Procedimientos Quirúrgicos Robotizados , Humanos , Potenciales Evocados Visuales , Movimiento/fisiología , Computadores , Electroencefalografía/métodos
9.
Bioorg Chem ; 139: 106676, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37352720

RESUMEN

Neuronal PAS domain protein 3 (NPAS3), a basic helix-loop-helix PER-ARNT-SIM (bHLH-PAS) family member, is a pivotal transcription factor in neuronal regeneration, development, and related diseases, regulating the expression of downstream genes. Despite several modulators of certain bHLH-PAS family proteins being identified, the NPAS3-targeted compound has yet to be reported. Herein, we discovered a hit compound BI-78D3 that directly blocks the NPAS3-ARNT heterodimer formation by covalently binding to the aryl hydrocarbon receptor nuclear translocator (ARNT) subunit. Further optimization based on the hit scaffold yielded a highly potent Compound 6 with a biochemical EC50 value of 282 ± 61 nM and uncovered the 5-nitrothiazole-2-sulfydryl as a cysteine-targeting covalent warhead. Compound 6 effectively down-regulated NPAS3's transcriptional function by disrupting the interface of NPAS3-ARNT complexes at cellular level. In conclusion, our study identifies the 5-nitrothiazole-2-sulfydryl as a cysteine-modified warhead and provides a strategy that blocks the NPAS3-ARNT heterodimerization by covalently conjugating ARNT Cys336 residue. Compound 6 may serve as a promising chemical probe for exploring NPAS3-related physiological functions.


Asunto(s)
Translocador Nuclear del Receptor de Aril Hidrocarburo , Receptores de Hidrocarburo de Aril , Translocador Nuclear del Receptor de Aril Hidrocarburo/química , Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Cisteína/metabolismo , Unión Proteica , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo
10.
IEEE Trans Med Imaging ; 42(6): 1809-1821, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37022247

RESUMEN

Whole-slide image (WSI) classification is fundamental to computational pathology, which is challenging in extra-high resolution, expensive manual annotation, data heterogeneity, etc. Multiple instance learning (MIL) provides a promising way towards WSI classification, which nevertheless suffers from the memory bottleneck issue inherently, due to the gigapixel high resolution. To avoid this issue, the overwhelming majority of existing approaches have to decouple the feature encoder and the MIL aggregator in MIL networks, which may largely degrade the performance. Towards this end, this paper presents a Bayesian Collaborative Learning (BCL) framework to address the memory bottleneck issue with WSI classification. Our basic idea is to introduce an auxiliary patch classifier to interact with the target MIL classifier to be learned, so that the feature encoder and the MIL aggregator in the MIL classifier can be learned collaboratively while preventing the memory bottleneck issue. Such a collaborative learning procedure is formulated under a unified Bayesian probabilistic framework and a principled Expectation-Maximization algorithm is developed to infer the optimal model parameters iteratively. As an implementation of the E-step, an effective quality-aware pseudo labeling strategy is also suggested. The proposed BCL is extensively evaluated on three publicly available WSI datasets, i.e., CAMELYON16, TCGA-NSCLC and TCGA-RCC, achieving an AUC of 95.6%, 96.0% and 97.5% respectively, which consistently outperforms all the methods compared. Comprehensive analysis and discussion will also be presented for in-depth understanding of the method. To promote future work, our source code is released at: https://github.com/Zero-We/BCL.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Prácticas Interdisciplinarias , Neoplasias Pulmonares , Humanos , Teorema de Bayes , Algoritmos
11.
Med Image Anal ; 85: 102748, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36731274

RESUMEN

Computerized identification of lymph node metastasis of breast cancer (BCLNM) from whole-slide pathological images (WSIs) can largely benefit therapy decision and prognosis analysis. Besides the general challenges of computational pathology, like extra-high resolution, very expensive fine-grained annotation, etc., two particular difficulties with this task lie in (1) modeling the significant inter-tumoral heterogeneity in BCLNM pathological images, and (2) identifying micro-metastases, i.e., metastasized tumors with tiny foci. Towards this end, this paper presents a novel weakly supervised method, termed as Prototypical Multiple Instance Learning (PMIL), to learn to predict BCLNM from WSIs with slide-level class labels only. PMIL introduces the well-established vocabulary-based multiple instance learning (MIL) paradigm into computational pathology, which is characterized by utilizing the so-called prototypes to model pathological data and construct WSI features. PMIL mainly consists of two innovatively designed modules, i.e., the prototype discovery module which acquires prototypes from training data by unsupervised clustering, and the prototype-based slide embedding module which builds WSI features by matching constitutive patches against the prototypes. Relative to existing MIL methods for WSI classification, PMIL has two substantial merits: (1) being more explicit and interpretable in modeling the inter-tumoral heterogeneity in BCLNM pathological images, and (2) being more effective in identifying micro-metastases. Evaluation is conducted on two datasets, i.e., the public Camelyon16 dataset and the Zbraln dataset created by ourselves. PMIL achieves an AUC of 88.2% on Camelyon16 and 98.4% on Zbraln (at 40x magnification factor), which consistently outperforms other compared methods. Comprehensive analysis will also be carried out to further reveal the effectiveness and merits of the proposed method.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Metástasis Linfática , Pronóstico
12.
Eur Arch Otorhinolaryngol ; 280(4): 1621-1627, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36227348

RESUMEN

BACKGROUND: This study aimed to develop and validate a deep learning (DL) model to identify atelectasis and attic retraction pocket in cases of otitis media with effusion (OME) using multi-center otoscopic images. METHOD: A total of 6393 OME otoscopic images from three centers were used to develop and validate a DL model for detecting atelectasis and attic retraction pocket. A threefold random cross-validation procedure was adopted to divide the dataset into training validation sets on a patient level. A team of otologists was assigned to diagnose and characterize atelectasis and attic retraction pocket in otoscopic images. Receiver operating characteristic (ROC) curves, including area under the ROC curve (AUC), accuracy, sensitivity, and specificity were used to assess the performance of the DL model. Class Activation Mapping (CAM) illustrated the discriminative regions in the otoscopic images. RESULTS: Among all OME otoscopic images, 3564 (55.74%) were identified with attic retraction pocket, and 2460 (38.48%) with atelectasis. The diagnostic DL model of attic retraction pocket and atelectasis achieved a threefold cross-validation accuracy of 89% and 79%, AUC of 0.89 and 0.87, a sensitivity of 0.93 and 0.71, and a specificity of 0.62 and 0.84, respectively. Larger and deeper cases of atelectasis and attic retraction pocket showed greater weight, based on the red color depicted in the heat map of CAM. CONCLUSION: The DL algorithm could be employed to identify atelectasis and attic retraction pocket in otoscopic images of OME, and as a tool to assist in the accurate diagnosis of OME.


Asunto(s)
Aprendizaje Profundo , Otitis Media con Derrame , Otitis Media , Atelectasia Pulmonar , Humanos , Oído Medio , Otitis Media con Derrame/diagnóstico , Otitis Media con Derrame/diagnóstico por imagen , Membrana Timpánica
13.
Ann Transl Med ; 10(8): 494, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35571427

RESUMEN

Background: Immunoglobulin (Ig) A nephropathy (IgAN) with a membranoproliferative pattern of injury that manifests as nephrotic syndrome (NS) is rarely reported in hepatitis C virus (HCV)-induced cirrhosis. It is not known whether eradication of HCV by direct-acting antiviral (DAA) drugs can lead to remission of proteinuria and improve the long-term prognosis. Case Description: We report the case of a 52-year-old woman with HCV cirrhosis for 10 years. She had undergone splenectomy and cholecystectomy due to complications of liver cirrhosis. The patient presented with NS and was diagnosed by kidney biopsy with IgAN with a membranoproliferative pattern of injury. Twelve-week sofosbuvir and ledipasvir therapy successfully eradicated HCV in this decompensated cirrhosis patient and resulted in partial remission of IgAN. The patient stayed in partial remission for 4 years and had her first relapse with deterioration of portal hypertension and suspected hepatic carcinoma despite a sustained HCV virologic response. We consider the IgAN in this case to be secondary to liver cirrhosis and HCV infection rather than a primary nephropathy. DAA drugs which have no direct reno-protective effect resulted in partial remission of IgAN because they eradicated HCV and improved the liver disorder. Conclusions: Although relapse of IgAN could occur when liver cirrhosis deteriorates, DAA treatment may be considered an alternative for similar patients.

14.
ACS Appl Mater Interfaces ; 14(18): 21474-21485, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35486453

RESUMEN

Multiresponsive and high-performance flexible actuators with a simple configuration, high mechanical strength, and low-power consumption are highly desirable for soft robotics. Here, a novel mechanically robust and multiresponsive Ti3C2Tx MXene-based actuator with high actuation performance via dual-mechanism synergistic effect driven by the hygroexpansion of bacterial cellulose (BC) layer and the thermal expansion of biaxially oriented polypropylene (BOPP) layer is developed. The actuator is flexible and shows an ultrahigh tensile strength of 195 MPa. Unlike the conventional bimorph-structured actuators based on a single-mechanism, the actuator developed provides a favorable architecture for dual-mechanism synergism, resulting in exceptionally reversible actuation performance under electricity and near-infrared (NIR) light stimuli. Typically, the developed actuator can produce the largest bending angle (∼400°) at the lowest voltage (≤4 V) compared with that reported previously for single mechanism soft actuators. Furthermore, the actuator also can be driven by a NIR light at a 2 m distance, displaying an excellent long-distance photoresponsive property. Finally, various intriguing applications are demonstrated to show the great potential of the actuator for soft robotics.

15.
Bioorg Med Chem ; 52: 116512, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34801827

RESUMEN

Histone acetylation is one of the most essential parts of epigenetic modification, mediating a variety of complex biological functions. In these procedure, p300/CBP could catalyze the acetylation of lysine 27 on histone 3 (H3K27ac), and had been reported to mediate tumorigenesis and development in a variety of tumors by enhancing chromatin transcription activity. Ovarian cancer, as an extremely malignant tumor, has also been observed to undergo abnormal acetylation of histones. However, whether the treatment of ovarian cancer could be achieved by inhibiting the acetylation activity of p300/CBP on H3K27 has not been well investigated. In this article, we modified the structure of p300/CBP HAT domain inhibitor A-485 and obtained a highly active small molecule known as 13f, which has an IC50 value of 0.49 nM for inhibiting the in vitro enzyme activity of p300, as well as the anti-proliferation IC50 value on ovarian cancer cell line OVCAR-3 was 153 nM. In addition, 13f had strong acetylase family selectivity, good metabolic stability and promising in vivo anti-tumor activity in OVCAR-3 xenograft model. The discovery of 13f revealed a more active chemical entity of the HATs domain of p300/CBP and provided a novel idea for the application of epigenetic inhibitors in the treatment of ovarian cancer.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Oxazoles/farmacología , Compuestos de Espiro/farmacología , Factores de Transcripción p300-CBP/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Femenino , Humanos , Estructura Molecular , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Oxazoles/síntesis química , Oxazoles/química , Compuestos de Espiro/síntesis química , Compuestos de Espiro/química , Relación Estructura-Actividad , Factores de Transcripción p300-CBP/metabolismo
16.
J Med Chem ; 64(12): 8194-8207, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-34077206

RESUMEN

Disruption of EZH2-embryonic ectoderm development (EED) protein-protein interaction (PPI) is a new promising cancer therapeutic strategy. We have previously reported the discovery of astemizole, a small-molecule inhibitor targeting the EZH2-EED PPI. Herein, we report the cocrystal structure of EED in complex with astemizole at 2.15 Å. The structure elucidates the detailed binding mode of astemizole to EED and provides a structure-guided design for the discovery of a novel EZH2-EED interaction inhibitor, DC-PRC2in-01, with an affinity Kd of 4.56 µM. DC-PRC2in-01 destabilizes the PRC2 complex, thereby leading to the degradation of PRC2 core proteins and the decrease of global H3K27me3 levels in cancer cells. The proliferation of PRC2-driven lymphomas cells is effectively inhibited, and the cell cycle is arrested in the G0/G1 phase. Together, these data demonstrate that DC-PRC2in-01 could be an effective chemical probe for investigating the PRC2-related physiology and pathology and providing a promising chemical scaffold for further development.


Asunto(s)
Astemizol/análogos & derivados , Astemizol/farmacología , Proteína Potenciadora del Homólogo Zeste 2/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Complejo Represivo Polycomb 2/antagonistas & inhibidores , Unión Proteica/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Reposicionamiento de Medicamentos , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Inhibidores Enzimáticos/síntesis química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Complejo Represivo Polycomb 2/metabolismo , Relación Estructura-Actividad
17.
Eur J Med Chem ; 215: 113281, 2021 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-33611192

RESUMEN

Cyclin-dependent kinases play significant roles in cell cycle progression and are promising targets for cancer therapy. However, most potent CDK inhibitors lack the balance between efficacy and safety because of poor selectivity. Given the roles of CDK2 in tumorigenesis, selective CDK2 inhibition may provide therapeutic benefits against certain cancer. In this study, a series of 4-benzoylamino-1H-pyrazole-3-carboxamide derivatives were designed, synthesized, and evaluated. The most selective compound DC-K2in212 in this series exhibited high potency towards CDK2 and had effective anti-proliferative activity against A2058 melanoma cell line and MV4-11 leukemia cell line while exhibiting low toxic effect on human normal cell lines MRC5 and LX2. The molecular modeling illustrated that compound DC-K2in212 had the similar binding mode with CDK2 as C-73, the most selective CDK2 inhibitor reported so far, which might account for selectivity against CDK2 over CDK1. Further biological studies revealed that compound DC-K2in212 suppressed CDK2-associated downstream signaling pathway, blocked cell cycle progression, and induced cellular apoptosis. Therefore, compound DC-K2in212 could serve as a potential CDK2 inhibitor for further development.


Asunto(s)
Benzamidas/farmacología , Quinasa 2 Dependiente de la Ciclina/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzamidas/síntesis química , Benzamidas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Quinasa 2 Dependiente de la Ciclina/metabolismo , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Unión Proteica , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/metabolismo , Pirazoles/síntesis química , Pirazoles/metabolismo , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad
18.
BMJ Open ; 11(1): e041139, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33478963

RESUMEN

OBJECTIVES: This study investigated the usefulness and performance of a two-stage attention-aware convolutional neural network (CNN) for the automated diagnosis of otitis media from tympanic membrane (TM) images. DESIGN: A classification model development and validation study in ears with otitis media based on otoscopic TM images. Two commonly used CNNs were trained and evaluated on the dataset. On the basis of a Class Activation Map (CAM), a two-stage classification pipeline was developed to improve accuracy and reliability, and simulate an expert reading the TM images. SETTING AND PARTICIPANTS: This is a retrospective study using otoendoscopic images obtained from the Department of Otorhinolaryngology in China. A dataset was generated with 6066 otoscopic images from 2022 participants comprising four kinds of TM images, that is, normal eardrum, otitis media with effusion (OME) and two stages of chronic suppurative otitis media (CSOM). RESULTS: The proposed method achieved an overall accuracy of 93.4% using ResNet50 as the backbone network in a threefold cross-validation. The F1 Score of classification for normal images was 94.3%, and 96.8% for OME. There was a small difference between the active and inactive status of CSOM, achieving 91.7% and 82.4% F1 scores, respectively. The results demonstrate a classification performance equivalent to the diagnosis level of an associate professor in otolaryngology. CONCLUSIONS: CNNs provide a useful and effective tool for the automated classification of TM images. In addition, having a weakly supervised method such as CAM can help the network focus on discriminative parts of the image and improve performance with a relatively small database. This two-stage method is beneficial to improve the accuracy of diagnosis of otitis media for junior otolaryngologists and physicians in other disciplines.


Asunto(s)
Redes Neurales de la Computación , Neuroendoscopía/métodos , Otitis Media/diagnóstico por imagen , Membrana Timpánica/diagnóstico por imagen , China , Humanos , Neuroendoscopía/instrumentación , Reproducibilidad de los Resultados , Estudios Retrospectivos
19.
Eur J Med Chem ; 211: 113091, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33338869

RESUMEN

Cyclin-dependent kinase 9 (CDK9) is an increasingly important potential cancer treatment target. Nowadays, developing selective CDK9 inhibitors has been extremely challenging as its ATP-binding sites are similar with other CDKs. Here, we report that the CDK9 inhibitor BAY-1143572 is converted into a series of proteolysis targeting chimeras (PROTACs) which leads to several compounds inducing the degradation of CDK9 in acute myeloid leukemia cells at a low nanomolar concentration. In addition, the most potent PROTAC molecule B03 could inhibit cell growth more effectively than warhead alone, with little inhibition of other kinases. This enhanced antiproliferative activity is mediated by a slight increase in kinase inhibitory activity and an increase in the level of apoptosis induction. Moreover, B03 could induce the degradation of CDK9 in vivo. Our work provides evidence that B03 represents a lead for further development and that CDK9 degradation is a potential valuable therapeutic strategy in acute myeloid leukemia.


Asunto(s)
Quinasa 9 Dependiente de la Ciclina , Leucemia Mieloide Aguda , Inhibidores de Proteínas Quinasas , Humanos , Proliferación Celular , Quinasa 9 Dependiente de la Ciclina/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico
20.
ACS Appl Mater Interfaces ; 13(1): 1431-1440, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33356105

RESUMEN

It is highly desirable to develop green and renewable structural materials from biomaterials to replace synthetic materials involved from civil engineering to aerospace industries. Herein, we put forward a facile but effective top-down strategy to convert natural bamboo into bamboo steel. The fabrication process of bamboo steel involves the removal of lignin and hemicellulose, freeze-drying followed by epoxy infiltration, and densification combined with in situ solidification. The prepared bamboo steel is a super-strong composite material with a high specific tensile strength (302 MPa g-1 cm3), which is higher than that (227 MPa g-1 cm3) of conventional high specific strength steel. The bamboo steel demonstrates a high tensile strength of 407.6 MPa, a record flexural strength of 513.8 MPa, and a high toughness of 14.08 MJ/m3, which is improved by 360, 290, and 380% over those of natural bamboo, respectively. Particularly, the mechanical properties of the bamboo steel are the highest among the biofiber-reinforced polymer composites reported previously. The well-preserved bamboo scaffolds assure the integrity of bamboo fibers, while the densification under high pressure results in a high-fiber volume fraction with an improved hydrogen bonding among the adjacent bamboo fibers, and the epoxy resin impregnated enhances the stress transfer because of its chemical crosslinking with cellulose molecules. These endow the bamboo steel with superior mechanical performance. Furthermore, the bamboo steel demonstrates an excellent thermal insulating capability with a low thermal conductivity (about 0.29 W/mK). In addition, the bamboo steel shows a low coefficient of thermal expansion (about 6.3 × 10-6 K-1) and a very high-dimensional stability to moisture attack. The strategy of fabricating high-performance bamboo steel with green and abundant natural bamboo as raw materials is highly attractive for the sustainable development of structural engineering materials.

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