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Endocrine-resistant ER+HER2- breast cancer (BC) is particularly aggressive and leads to poor clinical outcomes. Effective therapeutic strategies against endocrine-resistant BC remain elusive. Here, analysis of the RNA-sequencing data from ER+HER2- BC patients receiving neoadjuvant endocrine therapy and spatial transcriptomics analysis both show the downregulation of innate immune signaling sensing cytosolic DNA, which primarily occurs in endocrine-resistant BC cells, not immune cells. Indeed, compared with endocrine-sensitive BC cells, the activity of sensing cytosolic DNA through the cGAS-STING pathway is attenuated in endocrine-resistant BC cells. Screening of kinase inhibitor library show that this effect is mainly mediated by hyperactivation of AKT1 kinase, which binds to kinase domain of TBK1, preventing the formation of a trimeric complex TBK1/STING/IRF3. Notably, inactivation of cGAS-STING signaling forms a positive feedback loop with hyperactivated AKT1 to promote endocrine resistance, which is physiologically important and clinically relevant in patients with ER+HER2- BC. Blocking the positive feedback loop using the combination of an AKT1 inhibitor with a STING agonist results in the engagement of innate and adaptive immune signaling and impairs the growth of endocrine-resistant tumors in humanized mice models, providing a potential strategy for treating patients with endocrine-resistant BC.
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Targeting ferroptosis for cancer therapy has slowed because of an incomplete understanding of ferroptosis mechanisms under specific pathological contexts such as tumorigenesis and cancer treatment. Here, we identify TRPML1-mediated lysosomal exocytosis as a potential anti-ferroptotic process through genome-wide CRISPR-Cas9 activation and kinase inhibitor library screening. AKT directly phosphorylated TRPML1 at Ser343 and inhibited K552 ubiquitination and proteasome degradation of TRPML1, thereby promoting TRPML1 binding to ARL8B to trigger lysosomal exocytosis. This boosted ferroptosis defense of AKT-hyperactivated cancer cells by reducing intracellular ferrous iron and enhancing membrane repair. Correlation analysis and functional analysis revealed that TRPML1-mediated ferroptosis resistance is a previously unrecognized feature of AKT-hyperactivated cancers and is necessary for AKT-driven tumorigenesis and cancer therapeutic resistance. TRPML1 inactivation or blockade of the interaction between TRPML1 and ARL8B inhibited AKT-driven tumorigenesis and cancer therapeutic resistance in vitro and in vivo by promoting ferroptosis. A synthetic peptide targeting TRPML1 inhibited AKT-driven tumorigenesis and enhanced the sensitivity of AKT-hyperactivated tumors to ferroptosis inducers, radiotherapy, and immunotherapy by boosting ferroptosis in vivo. Together, our findings identified TRPML1 as a therapeutic target in AKT-hyperactivated cancer.
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Ferroptose , Neoplasias , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Camundongos , Fatores de Ribosilação do ADP/metabolismo , Carcinogênese/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Ferroptose/efeitos dos fármacos , Lisossomos/metabolismo , Neoplasias/patologia , Neoplasias/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , UbiquitinaçãoRESUMO
The prognosis of patients with decompensated cirrhosis is poor, with significantly increased liver-related mortality rates. With the rising tide of decompensated cirrhosis associated with metabolic dysfunction-associated steatotic liver disease (MASLD), the role of metabolic bariatric surgery (MBS) in achieving hepatic recompensation is garnering increasing attention. However, the complexity of preoperative assessment, the risk of postoperative disease recurrence, and the potential for patients to experience surgical complications of the MBS present challenges. In this opinion article we analyze the potential of MBS to induce recompensation in MASLD-related cirrhosis, discuss the mechanisms by which MBS may affect recompensation, and compare the characteristics of different MBS procedures; we highlight the therapeutic potential of MBS in MASLD-related cirrhosis recompensation and advocate for research in this complex area.
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Recompensation has gained increasing attention in the field of cirrhosis, particularly in chronic liver disease with a definite aetiology. The current global prevalence of obesity and nonalcoholic fatty liver disease (NAFLD) is increasing, but there is currently a lack of a clear definition for recompensation in NAFLD-related cirrhosis. Here, we provide an up-to-date perspective on the natural history of NAFLD, emphasizing the reversible nature of the disease, summarizing possible mechanisms underlying recompensation in NAFLD, discussing challenges that need to be addressed and outlining future research directions in the field. Recompensation is a promising goal in patients with NAFLD-related cirrhosis, and further studies are needed to explore its underlying mechanisms and uncover its clinical features.
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Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Cirrose Hepática/complicações , Fibrose , Obesidade/complicações , Obesidade/epidemiologia , PrevisõesRESUMO
BACKGROUND AND AIM: The condition of hepatic fibrosis is hazardous. Therefore, it is vital that we investigate the mechanism of hepatic fibrosis to provide new targets for treatment. METHODS: Preliminary screening and research was carried out based on our prior results and our speculated role of the particle with quaternary structure arrangement (PAQosome) in hepatic fibrosis. The experiments were conducted using LX-2 or HepG2 cell lines by western blotting, quantitative real-time polymerase chain reaction, luciferase assays, and co-immunoprecipitation and were further validated in the Gene Expression Omnibus (GEO) database. RESULTS: We screened and proved that several subunits of the PAQosome regulate the development of liver fibrosis, including the asparagine synthetase domain-containing 1 upstream open reading frame (ASDURF), prefoldin subunit 4 (PFDN4), prefoldin subunit 5 (PFDN5), unconventional prefoldin RNA polymerase II subunit 5 interactor (URI1), and ubiquitously expressed prefoldin-like chaperone (UXT). ASDURF promotes hepatic fibrosis through the transforming growth factor-ß1 (TGFß1)/Sekelsky mothers against decapentaplegic homologue 3 (Smad3) and NF-κB signaling pathways. ASDURF regulates the expression of asparagine synthetase domain-containing 1 (ASNSD1). PFDN4, PFDN5, URI1, and UXT regulate cell proliferation through the PI3K/AKT pathway, and thus regulate liver fibrosis. A hepatic fibrosis score ≥ F2 was selected as the diagnostic criteria for hepatic fibrosis in the GSE96971 database. The area under the receiver operating characteristic curve of PFDN4, PFDN5, UXT, and ASNSD1 were 0.862 (confidence interval [CI]: 0.6588-1.000), 0.538 (CI: 0.224-0.853), 0.708 (CI: 0.449-0.966), and 0.831 (CI: 0.638-1.000), respectively. CONCLUSIONS: These findings demonstrate that the PAQosome is a brand new target for hepatic fibrosis therapy.
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Aspartato-Amônia Ligase , Humanos , Aspartato-Amônia Ligase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , NF-kappa B/metabolismo , Fibrose , Fator de Crescimento Transformador beta1/metabolismo , Células Estreladas do Fígado/metabolismo , Proteínas de Ciclo Celular/metabolismo , Chaperonas Moleculares/metabolismoRESUMO
Objective: To build a three-dimensional (3D) deep learning-based computer-aided diagnosis (CAD) system and investigate its applicability for automatic detection of anterior cruciate ligament (ACL) of the knee joint in magnetic resonance imaging (MRI). Methods: In this study, we develop a 3D weighted multi-view convolutional neural network by fusing different views of MRI to detect ACL. The network is evaluated on two MRI datasets, the in-house MRI-ACL dataset and the publicly available MRNet-v1.0 dataset. In the MRI-ACL dataset, the retrospective study collects 100 cases, and four views per patient are included. There are 50 ACL patients and 50 normal patients, respectively. The MRNet-v1.0 dataset contains 1,250 cases with three views, of which 208 are ACL patients, and the rest are normal or other abnormal patients. Results: The area under the receiver operating characteristic curve (AUC) of the ACL diagnosis system is 97.00% and 92.86% at the optimal threshold for the MRI-ACL dataset and the MRNet-v1.0 dataset, respectively, indicating a high overall diagnostic accuracy. In comparison, the best AUC of the single-view diagnosis methods are 96.00% (MRI-ACL dataset) and 91.78% (MRNet-v1.0 dataset), and our method improves by about 1.00% and 1.08%. Furthermore, our method also improves by about 1.00% (MRI-ACL dataset) and 0.28% (MRNet-v1.0 dataset) compared with the multi-view network (i.e., MRNet). Conclusion: The presented 3D weighted multi-view network achieves superior AUC in diagnosing ACL, not only in the in-house MRI-ACL dataset but also in the publicly available MRNet-v1.0 dataset, which demonstrates its clinical applicability for the automatic detection of ACL.
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BACKGROUND: As the most lethal gynecologic cancer, ovarian cancer (OV) holds the potential of being immunotherapy-responsive. However, only modest therapeutic effects have been achieved by immunotherapies such as immune checkpoint blockade. This study aims to propose a generalized stroma-immune prognostic signature (SIPS) to identify OV patients who may benefit from immunotherapy. METHODS: The 2097 OV patients included in the study were significant with high-grade serous ovarian cancer in the III/IV stage. The 470 immune-related signatures were collected and analyzed by the Cox regression and Lasso algorithm to generalize a credible SIPS. Correlations between the SIPS signature and tumor microenvironment were further analyzed. The critical immunosuppressive role of stroma indicated by the SIPS was further validated by targeting the major suppressive stroma component (CAFs, Cancer-associated fibroblasts) in vitro and in vivo. With four machine-learning methods predicting tumor immune subtypes, the stroma-immune signature was upgraded to a 23-gene signature. RESULTS: The SIPS effectively discriminated the high-risk individuals in the training and validating cohorts, where the high SIPS succeeded in predicting worse survival in several immunotherapy cohorts. The SIPS signature was positively correlated with stroma components, especially CAFs and immunosuppressive cells in the tumor microenvironment, indicating the critical suppressive stroma-immune network. The combination of CAFs' marker PDGFRB inhibitors and frontline PARP inhibitors substantially inhibited tumor growth and promoted the survival of OV-bearing mice. The stroma-immune signature was upgraded to a 23-gene signature to improve clinical utility. Several drug types that suppress stroma-immune signatures, such as EGFR inhibitors, could be candidates for potential immunotherapeutic combinations in ovarian cancer. CONCLUSIONS: The stroma-immune signature could efficiently predict the immunotherapeutic sensitivity of OV patients. Immunotherapy and auxiliary drugs targeting stroma could enhance immunotherapeutic efficacy in ovarian cancer.
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Síndrome de DiGeorge , Neoplasias Ovarianas , Feminino , Animais , Camundongos , Humanos , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Prognóstico , Neoplasias Ovarianas/tratamento farmacológico , Imunossupressores , Imunoterapia , Microambiente TumoralRESUMO
In recent years, homologous recombination deficiency (HRD) has not achieved the expected substantial promotion of immunotherapeutic efficacy in ovarian cancer. This study aims to explore the role of HRD functional phenotype as a powerful biomarker in identifying HRD patients who may benefit from immunotherapy. HRD functional phenotype, namely HRD-EXCUTE, was defined as the average level of the 15 hub genes upregulated in HRD ovarian cancer. A decision tree was plotted to evaluate the critical role of HRD-EXCUTE in HRD patients. Agents inducing HRD-EXCUTE were identified by CMAP web (Connectivity Map). The mechanisms and immunotherapeutic effect of PARPi and HDACi in promoting HRD-EXCUTE was examined in vitro and in vivo. The decision tree plotted on the basis of HRD and HRD-EXCUTE indicated the HRD patients without the HRD functional phenotype were largely unresponsive to immunotherapy, which was validated by the immunotherapeutic cohorts. Furthermore, loss of HRD-EXCUTE in the HRD patients attenuated immunogenicity and inhibited immune cells in tumor microenvironment. Moreover, Niraparib combined with Entinostat induced HRD-EXCUTE by activating the cGAS-STING pathway and increasing the histone acetylation. The combination therapy could enhance the cytotoxicity of immune cells, and promote pro-immune cells infiltrating into ascites, resulting in inhibited ovarian cancer growth. The HRD functional phenotype HRD-EXCUTE was set up as a potent biomarker to identify whether HRD patients can benefit from immunotherapy. Loss of HRD-EXCUTE in HRD patients were largely insensitive to immunotherapy. The combination of PARPi with HDACi could improve the efficacy of the PARPi-based immunotherapy in ovarian cancer by augmenting the HRD functional phenotype.
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Inibidores de Histona Desacetilases , Neoplasias Ovarianas , Humanos , Feminino , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Recombinação Homóloga , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Fenótipo , Microambiente TumoralRESUMO
BACKGROUND & AIMS: There is an unmet clinical need for non-invasive tests to diagnose non-alcoholic fatty liver disease (NAFLD) and individual fibrosis stages. We aimed to test whether urine protein panels could be used to identify NAFLD, NAFLD with fibrosis (stage F ≥ 1) and NAFLD with significant fibrosis (stage F ≥ 2). METHODS: We collected urine samples from 100 patients with biopsy-confirmed NAFLD and 40 healthy volunteers, and proteomics and bioinformatics analyses were performed in this derivation cohort. Diagnostic models were developed for detecting NAFLD (UPNAFLD model), NAFLD with fibrosis (UPfibrosis model), or NAFLD with significant fibrosis (UPsignificant fibrosis model). Subsequently, the derivation cohort was divided into training and testing sets to evaluate the efficacy of these diagnostic models. Finally, in a separate independent validation cohort of 100 patients with biopsy-confirmed NAFLD and 45 healthy controls, urinary enzyme-linked immunosorbent assay analyses were undertaken to validate the accuracy of these new diagnostic models. RESULTS: The UPfibrosis model and the UPsignificant fibrosis model showed an AUROC of .863 (95% CI: .725-1.000) and 0.858 (95% CI: .712-1.000) in the training set; and .837 (95% CI: .711-.963) and .916 (95% CI: .825-1.000) in the testing set respectively. The UPNAFLD model showed an excellent diagnostic performance and the area under the receiver operator characteristic curve (AUROC) exceeded .90 in the derivation cohort. In the independent validation cohort, the AUROC for all three of the above diagnostic models exceeded .80. CONCLUSIONS: Our newly developed models constructed from urine protein biomarkers have good accuracy for non-invasively diagnosing liver fibrosis in NAFLD.
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Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Cirrose Hepática/patologia , Fibrose , Biomarcadores/metabolismo , Biópsia , Fígado/patologiaRESUMO
Ferroptosis, an iron-dependent lipid peroxidation-driven programmed cell death, is closely related to cancer therapy. The development of druggable ferroptosis inducers and their rational application in cancer therapy are critical. Here, we identified Tubastatin A, an HDAC6 inhibitor as a novel druggable ferroptosis inducer through large-scale drug screening. Tubastatin A directly bonded to GPX4 and inhibited GPX4 enzymatic activity through biotin-linked Tubastatin A putdown and LC/MS analysis, which is independent of its inhibition of HDAC6. In addition, our results showed that radiotherapy not only activated Nrf2-mediated GPX4 transcription but also inhibited lysosome-mediated GPX4 degradation, subsequently inducing ferroptosis tolerance and radioresistance in cancer cells. Tubastatin A overcame ferroptosis resistance and radioresistance of cancer cells by inhibiting GPX4 enzymatic activity. More importantly, Tubastatin A has excellent bioavailability, as demonstrated by its ability to significantly promote radiotherapy-induced lipid peroxidation and tumour suppression in a mouse xenograft model. Our findings identify a novel druggable ferroptosis inducer, Tubastatin A, which enhances radiotherapy-mediated antitumor effects. This work provides a compelling rationale for the clinical evaluation of Tubastatin A, especially in combination with radiotherapy.
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Ferroptose , Neoplasias , Humanos , Animais , Camundongos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Apoptose , Peroxidação de LipídeosRESUMO
BACKGROUND: Liver biopsy for the diagnosis of non-alcoholic steatohepatitis (NASH) is limited by its inherent invasiveness and possible sampling errors. Some studies have shown that cytokeratin-18 (CK-18) concentrations may be useful in diagnosing NASH, but results across studies have been inconsistent. We aimed to identify the utility of CK-18 M30 concentrations as an alternative to liver biopsy for non-invasive identification of NASH. METHODS: Individual data were collected from 14 registry centers on patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD), and in all patients, circulating CK-18 M30 levels were measured. Individuals with a NAFLD activity score (NAS) ≥5 with a score of ≥1 for each of steatosis, ballooning, and lobular inflammation were diagnosed as having definite NASH; individuals with a NAS ≤2 and no fibrosis were diagnosed as having non-alcoholic fatty liver (NAFL). RESULTS: A total of 2571 participants were screened, and 1008 (153 with NAFL and 855 with NASH) were finally enrolled. Median CK-18 M30 levels were higher in patients with NASH than in those with NAFL (mean difference 177 U/L; standardized mean difference [SMD]: 0.87 [0.69-1.04]). There was an interaction between CK-18 M30 levels and serum alanine aminotransferase, body mass index (BMI), and hypertension ( P â<â0.001, P â=â0.026 and P â=â0.049, respectively). CK-18 M30 levels were positively associated with histological NAS in most centers. The area under the receiver operating characteristics (AUROC) for NASH was 0.750 (95% confidence intervals: 0.714-0.787), and CK-18 M30 at Youden's index maximum was 275.7 U/L. Both sensitivity (55% [52%-59%]) and positive predictive value (59%) were not ideal. CONCLUSION: This large multicenter registry study shows that CK-18 M30 measurement in isolation is of limited value for non-invasively diagnosing NASH.
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Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Queratina-18 , Biomarcadores , Biópsia , Hepatócitos/patologia , Apoptose , Fígado/patologiaRESUMO
Five undescribed indole alkaloids, fusarindoles A-E, together with seven known compounds were obtained from the marine-derived fungus Fusarium equiseti LJ-1. Their chemical structures and absolute configurations were determined by comprehensive analysis of the NMR, HRMS, UV, IR, ECD calculation and single-crystal X-ray diffraction data. The possible biosynthetic pathways of fusarindoles C-E were proposed. The cytotoxicities of eleven compounds, including fusarindoles A-E and six known compounds, against five human cancer cell lines A549, CNE2, SUNE1, HepG2 and QGY7701 were evaluated.
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BACKGROUND AND AIM: Over 10% of hepatocellular carcinoma (HCC) cases recur each year, even after surgical resection. Currently, there is a lack of knowledge about the causes of recurrence and the effective prevention. Prediction of HCC recurrence requires diagnostic markers endowed with high sensitivity and specificity. This study aims to identify new key proteins for HCC recurrence and to build machine learning algorithms for predicting HCC recurrence. METHODS: The proteomics data for analysis in this study were obtained from the Clinical Proteomics Tumor Analysis Consortium (CPTAC) database. We analyzed different proteins based on cases with or without recurrence of HCC. Survival analysis, Cox regression analysis, and area under the ROC curves (AUROC > 0.7) were used to screen for more significant differential proteins. Predictive models for HCC recurrence were developed using four machine learning algorithms. RESULTS: A total of 690 differentially expressed proteins between 50 relapsed and 77 non-relapsed hepatitis B-related HCC patients were identified. Seven of these proteins had an AUROC > 0.7 for 5-year survival in HCC, including BAHCC1, ESF1, RAP1GAP, RUFY1, SCAMP3, STK3, and TMEM230. Among the machine learning algorithms, the random forest algorithm showed the highest AUROC values (AUROC: 0.991, 95% CI 0.962-0.999) for identifying HCC recurrence, followed by the support vector machine (AUROC: 0.893, 95% Cl 0.824-0.956), the logistic regression (AUROC: 0.774, 95% Cl 0.672-0.868), and the multi-layer perceptron algorithm (AUROC: 0.571, 95% Cl 0.459-0.682). CONCLUSIONS: Our study identifies seven novel proteins for predicting HCC recurrence and the random forest algorithm as the most suitable predictive model for HCC recurrence.
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Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Doença de Parkinson , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Proteômica , Proteínas de Membrana , Algoritmos , Aprendizado de Máquina , Mineração de Dados , Proteínas Serina-Treonina Quinases , Proteínas de TransporteRESUMO
INTRODUCTION AND OBJECTIVES: It is well known that the quality of life (QoL) of patients with chronic hepatitis C (HCV) is lower than that of the general population and that therapy with direct-acting antivirals (DAA) for HCV is safe and effective. However, data on the QoL of patients are scanty. The purpose of this study was to assess the effect of DAA drugs on patients' QoL. METHODS: The literature included in this meta-analysis was due in March 2021. The random effect model of heterogeneous data and the fixed effect model of homogeneous data were used to analyze the data. QoL had to be evaluated using the Short Form Health Survey (SF-36) questionnaire with at least one measure at baseline (T0) and one measure at 12 weeks (T12) or 24 weeks (T24) after the end of therapy. The meta-analysis included eight studies, which involved 1,619 patients. RESULTS: At T12, the meta-analysis showed all items of the SF-36 questionnaire improved from the pretreatment to post-treatment period and reached statistical significance (p < 0.05) except for the bodily pain (mean difference: 1.16, 95%CI -0.43-2.74) and role limitations-emotional (mean difference: 4.10, 95%CI -1.32-9.52). However, after subgroup analysis (whether ribavirin was being used or not), the bodily pain domain (mean difference: 3.34, 95%CI 1.03-5.65) became statistically significant again. At T24, the results indicated that all items of the SF-36 questionnaire improved from the pretreatment to the post-treatment period and reached statistical significance (p < 0.05) except for the role limitations-emotional domain (mean difference: 4.50, 95%CI -2.66-11.66). CONCLUSIONS: There is evidence indicating that DAA therapy is accompanied by an improvement in QoL. Patients receiving DAA medication have a clinically relevant improvement in most domains of the SF-36 questionnaire at T12 or T24, except for a few aspects including role limitations-emotional.
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Hepatite C Crônica , Hepatite C , Antivirais/efeitos adversos , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Humanos , Dor , Qualidade de VidaRESUMO
Non-alcoholic fatty liver disease (NAFLD), recently re-defined and re-classified as metabolic dysfunction-associated fatty liver disease (MAFLD), has become increasingly prevalent and emerged as a public health problem worldwide. To date, the precise pathogenic mechanisms underpinning MAFLD are not entirely understood, and there is no effective pharmacological therapy for NAFLD/MAFLD. As a newly discovered form of iron-dependent programmed cell death, ferroptosis can be involved in the development and progression of various chronic diseases, but the pathogenic connections and mechanisms that link MAFLD and ferroptosis have not been fully elucidated. The main characteristics of ferroptosis are the accumulation of lipid peroxides and reactive oxygen species. In this brief narrative review, the mechanisms of ferroptosis and its putative pathogenic role in MAFLD are discussed to highlight potential new research directions and ideas for the prevention and treatment of MAFLD.
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Ferroptose , Hepatopatia Gordurosa não Alcoólica , Humanos , Espécies Reativas de Oxigênio/metabolismoRESUMO
The accumulation of lipid peroxides is recognized as a determinant of the occurrence of ferroptosis. However, the sensors and amplifying process of lipid peroxidation linked to ferroptosis remain obscure. Here we identify PKCßII as a critical contributor of ferroptosis through independent genome-wide CRISPR-Cas9 and kinase inhibitor library screening. Our results show that PKCßII senses the initial lipid peroxides and amplifies lipid peroxidation linked to ferroptosis through phosphorylation and activation of ACSL4. Lipidomics analysis shows that activated ACSL4 catalyses polyunsaturated fatty acid-containing lipid biosynthesis and promotes the accumulation of lipid peroxidation products, leading to ferroptosis. Attenuation of the PKCßII-ACSL4 pathway effectively blocks ferroptosis in vitro and impairs ferroptosis-associated cancer immunotherapy in vivo. Our results identify PKCßII as a sensor of lipid peroxidation, and the lipid peroxidation-PKCßII-ACSL4 positive-feedback axis may provide potential targets for ferroptosis-associated disease treatment.
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Coenzima A Ligases/metabolismo , Ferroptose/fisiologia , Peroxidação de Lipídeos/fisiologia , Proteína Quinase C beta/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Humanos , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/terapia , Fosforilação , Proteína Quinase C beta/genéticaRESUMO
Amino acid-directed strategy becomes an efficient way to explore the alkaloids' biosynthetic potential of marine fungi. The metabolites of marine fungus Monascus albidus BB3 were regulated obviously when cultured in GPY medium supplemented with L-tryptophan, L-phenylalanine, D,L-methionine, L-threonine, L-lysine, L-serine and L-valine. Four new γ-lactams, monascuslactams A-D (1-4), together with two known compounds pulchellalactam (5) and O-acetylperlolyrine (6) were obtained. Their structures were determined by comprehensive analysis on the 1 D and 2 D NMR, HRESIMS, UV and IR data, and their absolute configurations were assigned by the experimental and calculated ECD data analysis. Compounds 3, 4 and 6 showed moderate cytotoxicity against human cancer cell lines SUNE1, HepG2, QGY7701, GLC82, HCT116 and MDA-MB-231.