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1.
Adv Sci (Weinh) ; : e2403592, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023171

RESUMO

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.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38908982

RESUMO

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.

3.
Sci Transl Med ; 16(753): eadk0330, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38924427

RESUMO

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.


Assuntos
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 , Ubiquitinação
4.
J Transl Med ; 21(1): 586, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658364

RESUMO

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.


Assuntos
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 Tumoral
5.
Int J Biol Sci ; 19(6): 1846-1860, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063431

RESUMO

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.


Assuntos
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 Tumoral
6.
Liver Int ; 43(6): 1234-1246, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36924436

RESUMO

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.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Cirrose Hepática/patologia , Fibrose , Biomarcadores/metabolismo , Biópsia , Fígado/patologia
7.
Redox Biol ; 62: 102677, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36989572

RESUMO

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.


Assuntos
Ferroptose , Neoplasias , Humanos , Animais , Camundongos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Apoptose , Peroxidação de Lipídeos
8.
Chin Med J (Engl) ; 136(3): 341-350, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36848175

RESUMO

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  < 0.001, P  = 0.026 and P  = 0.049, 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.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Queratina-18 , Biomarcadores , Biópsia , Hepatócitos/patologia , Apoptose , Fígado/patologia
9.
Phytochemistry ; 204: 113456, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36179822

RESUMO

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.

10.
J Gastroenterol Hepatol ; 37(11): 2145-2153, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35816347

RESUMO

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.


Assuntos
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 Transporte
11.
Nat Cell Biol ; 24(1): 88-98, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35027735

RESUMO

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.


Assuntos
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/genética
12.
Nat Prod Res ; 36(10): 2534-2541, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33951987

RESUMO

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.


Assuntos
Antineoplásicos , Monascus , Antineoplásicos/química , Antineoplásicos/farmacologia , Fungos , Humanos , Lactamas , Estrutura Molecular
13.
Int J Gen Med ; 14: 8621-8630, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34849007

RESUMO

BACKGROUND: The aim of the study was to develop a nomogram to predict the overall survival (OS) of patients with solitary plasmacytoma of bone (SBP). MATERIALS AND METHODS: Patients diagnosed with SBP between 1993 and 2012 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. All eligible patients were randomly allocated to the training sets and the validation sets. The nomogram was developed with the training set and validated with the validation set using the concordance index (C-index), calibration plots, and decision curve analyses (DCA). RESULTS: Age, marital status, tumor grade, treatment were independent prognostic indicators for OS (P<0.05) and were integrated to construct the nomogram. C-indexes for OS prediction in the training and validation sets were 0.78 and 0.73, respectively. The calibration plots demonstrated good consistency between the predicted and actual survival. DCA demonstrated that the new model has great benefits. In the total cohort, the median OS of patients in the low- and high-risk groups were 12.17 (95% CI 11.92-12.42) and 3.92 (95% CI 2.83-5.01) years, respectively. CONCLUSION: The nomogram showed excellent applicability and accuracy, which could be a reliable tool for predicting OS in SBP patients.

14.
Signal Transduct Target Ther ; 6(1): 401, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34848680

RESUMO

Met tyrosine kinase, a receptor for a hepatocyte growth factor (HGF), plays a critical role in tumor growth, metastasis, and drug resistance. Mitochondria are highly dynamic and undergo fission and fusion to maintain a functional mitochondrial network. Dysregulated mitochondrial dynamics are responsible for the progression and metastasis of many cancers. Here, using structured illumination microscopy (SIM) and high spatial and temporal resolution live cell imaging, we identified mitochondrial trafficking of receptor tyrosine kinase Met. The contacts between activated Met kinase and mitochondria formed dramatically, and an intact HGF/Met axis was necessary for dysregulated mitochondrial fission and cancer cell movements. Mechanically, we found that Met directly phosphorylated outer mitochondrial membrane protein Fis1 at Tyr38 (Fis1 pY38). Fis1 pY38 promoted mitochondrial fission by recruiting the mitochondrial fission GTPase dynamin-related protein-1 (Drp1) to mitochondria. Fragmented mitochondria fueled actin filament remodeling and lamellipodia or invadopodia formation to facilitate cell metastasis in hepatocellular carcinoma (HCC) cells both in vitro and in vivo. These findings reveal a novel and noncanonical pathway of Met receptor tyrosine kinase in the regulation of mitochondrial activities, which may provide a therapeutic target for metastatic HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias Hepáticas/metabolismo , Dinâmica Mitocondrial , Proteínas Mitocondriais/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Carcinoma Hepatocelular/genética , Células HeLa , Humanos , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Mitocôndrias Hepáticas/genética , Proteínas Mitocondriais/genética , Fosforilação , Proteínas Proto-Oncogênicas c-met/genética
15.
Mol Med ; 27(1): 141, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34732133

RESUMO

BACKGROUND: We aimed to investigate the functions and underlying mechanism of lncRNA SNHG1 in bone differentiation and angiogenesis in the development of osteoporosis. METHODS: The differential gene or proteins expressions were measured by qPCR or western blot assays, respectively. The targeted relationships among molecular were confirmed through luciferase reporter, RIP and ChIP assays, respectively. Alkaline phosphatase (ALP), alizarin red S (ARS) and TRAP staining were performed to measure the osteoblast/osteoclast differentiation of BMSCs. The viability, migration and angiogenesis in BM-EPCs were validated by CCK-8, clone formation, transwell and tube formation assays, respectively. Western blot and immunofluorescence detected the cytosolic/nuclear localization of ß-catenin. Ovariectomized (OVX) mice were established to confirm the findings in vitro. RESULTS: SNHG1 was enhanced and miR-181c-5p was decreased in serum and femoral tissue from OVX mice. SNHG1 directly inhibited miR-181c-5p to activate Wnt3a/ß-catenin signaling by upregulating SFRP1. In addition, knockdown of SNHG1 promoted the osteogenic differentiation of BMSCs by increasing miR-181c-5p. In contrast, SNHG1 overexpression advanced the osteoclast differentiation of BMSCs and inhibited the angiogenesis of BM-EPCs, whereas these effects were all reversed by miR-181c-5p overexpression. In vivo experiments indicated that SNHG1 silencing alleviated osteoporosis through stimulating osteoblastogenesis and inhibiting osteoclastogenesis by modulating miR-181c-5p. Importantly, SNHG1 could be induced by SP1 in BMSCs. CONCLUSIONS: Collectively, SP1-induced SNHG1 modulated SFRP1/Wnt/ß-catenin signaling pathway via sponging miR-181c-5p, thereby inhibiting osteoblast differentiation and angiogenesis while promoting osteoclast formation. Further, SNHG1 silence might provide a potential treatment for osteoporosis.


Assuntos
Remodelação Óssea/genética , MicroRNAs , Osteoporose/genética , RNA Longo não Codificante , Fator de Transcrição Sp1/genética , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica , Transdução de Sinais , Células-Tronco/citologia , Proteína Wnt3A/metabolismo
16.
Nat Commun ; 12(1): 2672, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976130

RESUMO

Most patients with triple negative breast cancer (TNBC) do not respond to anti-PD1/PDL1 immunotherapy, indicating the necessity to explore immune checkpoint targets. B7H3 is a highly glycosylated protein. However, the mechanisms of B7H3 glycosylation regulation and whether the sugar moiety contributes to immunosuppression are unclear. Here, we identify aberrant B7H3 glycosylation and show that N-glycosylation of B7H3 at NXT motif sites is responsible for its protein stability and immunosuppression in TNBC tumors. The fucosyltransferase FUT8 catalyzes B7H3 core fucosylation at N-glycans to maintain its high expression. Knockdown of FUT8 rescues glycosylated B7H3-mediated immunosuppressive function in TNBC cells. Abnormal B7H3 glycosylation mediated by FUT8 overexpression can be physiologically important and clinically relevant in patients with TNBC. Notably, the combination of core fucosylation inhibitor 2F-Fuc and anti-PDL1 results in enhanced therapeutic efficacy in B7H3-positive TNBC tumors. These findings suggest that targeting the FUT8-B7H3 axis might be a promising strategy for improving anti-tumor immune responses in patients with TNBC.


Assuntos
Antígenos B7/metabolismo , Fucosiltransferases/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Antígenos B7/genética , Linhagem Celular Tumoral , Feminino , Fucose/metabolismo , Fucosiltransferases/genética , Técnicas de Inativação de Genes , Glicosilação , Células HEK293 , Humanos , Imunidade , Estimativa de Kaplan-Meier , Camundongos Endogâmicos BALB C , Camundongos SCID , Polissacarídeos/metabolismo , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
17.
Autophagy ; 17(12): 4323-4340, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33977871

RESUMO

Macroautophagy/autophagy plays an important role during the development of human cancer. BECN1 (beclin 1), a core player in autophagy regulation, is downregulated in many kinds of malignancy. The underlying mechanism, however, has not been fully illuminated. Here, we found that CUL3 (cullin 3), an E3 ubiquitin ligase, could interact with BECN1 and promote the K48-linked ubiquitination and degradation of this protein; In addition, CUL3 led to a decrease in autophagic activity through downregulating BECN1. We also found that KLHL38 was a substrate adaptor of the CUL3 E3 ligase complex-mediated ubiquitination and degradation of BECN1. In breast and ovarian cancer, CUL3 could promote the proliferation of tumor cells, and the expression of CUL3 was related to poor prognosis in patients. Our study reveals the underlying mechanism of BECN1 ubiquitination and degradation that affects autophagic activity and subsequently leads to tumor progression, providing a novel therapeutic strategy that regulates autophagy to combat cancer.Abbreviations: ATG: autophagy-related BECN1: beclin 1 CHX: cycloheximide CoIP: co-immunoprecipitation CUL3: cullin 3 IP: immunoprecipitation MS: mass spectrometry PtdIns3K: phosphatidylinositol 3-kinase UPS: ubiquitin-proteasome system.


Assuntos
Autofagia , Proteínas Culina , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Proteínas Culina/metabolismo , Humanos , Ubiquitina/metabolismo , Ubiquitinação
18.
J Hepatobiliary Pancreat Sci ; 28(7): 593-603, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33908180

RESUMO

BACKGROUND: The presence of significant liver fibrosis is a key determinant of long-term prognosis in non-alcoholic fatty liver disease (NAFLD). We aimed to develop a novel machine learning algorithm (MLA) to predict fibrosis severity in NAFLD and compared it with the most widely used non-invasive fibrosis biomarkers. METHODS: We used a cohort of 553 adults with biopsy-proven NAFLD, who were randomly divided into a training cohort (n = 278) for the development of both logistic regression model (LRM) and MLA, and a validation cohort (n = 275). Significant fibrosis was defined as fibrosis stage F ≥ 2. MLA and LRM were derived from variables that were selected using a least absolute shrinkage and selection operator (LASSO) logistic regression algorithm. RESULTS: In the training cohort, the variables selected by LASSO algorithm were body mass index, pro-collagen type III, collagen type IV, aspartate aminotransferase and albumin-to-globulin ratio. The diagnostic accuracy of MLA showed the highest values of area under the receiver operator characteristic curve (AUROC: 0.902, 95% CI 0.869-0.904) for identifying fibrosis F ≥ 2. The LRM AUROC was 0.764, 95% CI 0.710-0.816 and significantly better than the AST-to-Platelet ratio (AUROC 0.684, 95% CI 0.605-0.762), FIB-4 score (AUROC 0.594, 95% CI 0.503-0.685) and NAFLD Fibrosis Score (AUROC 0.557, 95% CI 0.470-0.644). In the validation cohort, MLA also showed the highest AUROC (0.893, 95% CI 0.864-0.901). The diagnostic accuracy of MLA outperformed that of LRM in all subgroups considered. CONCLUSIONS: Our newly developed MLA algorithm has excellent diagnostic performance for predicting fibrosis F ≥ 2 in patients with biopsy-confirmed NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Algoritmos , Biomarcadores , Biópsia , Fibrose , Humanos , Cirrose Hepática/diagnóstico , Aprendizado de Máquina , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Valor Preditivo dos Testes , Curva ROC , Índice de Gravidade de Doença
19.
Chem Biodivers ; 18(5): e2100068, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33811740

RESUMO

Five new decalins, monalbidins A-E (1, 2 and 7-9), together with 16 known compounds (3-6 and 10-21), were isolated from the AcOEt extract of marine derived fungus Monascus albidus BB3 cultured in GPY medium. Among the known compounds, 1-hydroxymonacolin L (11), dehydromonacolin J (15), 8-O-acetylmonacolin J (19) and O-acetylmonacolin K (21) were separated from natural sources for the first time. Their structures were determined by comprehensive analysis on the 1D and 2D NMR, HR-ESI-MS, UV and IR data, and their absolute configurations were assigned by experimental and calculated ECD data, and X-ray single-crystal diffraction analysis. Monalbidins C and D (7 and 8), monacolin K methyl ester (13), dehydromonacolin L (14), dehydromonacolin K (16), monacolin K (20) and O-acetylmonacolin K (21) showed moderate cytotoxicity against human cancer cell lines SUNE1, HepG2, QGY7701, HCT116 and MDA-MB-231.


Assuntos
Antineoplásicos/farmacologia , Monascus/química , Naftalenos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Conformação Molecular , Naftalenos/química , Naftalenos/isolamento & purificação , Estereoisomerismo
20.
Oncogene ; 40(13): 2422-2436, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664452

RESUMO

Polycomb repressor complex 1 (PRC1) is linked to the regulation of gene expression and histone ubiquitylation conformation, which contributes to carcinogenesis. However, the upstream regulators of PRC1 biogenesis machinery remain obscure. Here, we report that the polycomb group-related mammalian gene Mel18 is a target of the protein kinase AKT. AKT phosphorylates Mel18 at T334 to disrupt the interaction between Mel18 and other PRC1 members, leading to attenuated PRC1-dependent ubiquitylation of histone H2A at Lys119. As such, PRC1 target genes, many of which are known oncogenes, are derepressed upon T334-Mel18 phosphorylation, which promotes malignant behaviours, including cell proliferation, tumour formation, migration and invasion, bone and brain metastatic lesion formation. Notably, a positive correlation between AKT activity and pT334-Mel18 is observed, and prognostic models based on p-AKT and pT334-Mel18 that predicted overall survival and distant metastasis-free survival in breast cancer patients are established. These findings have implications for understanding the role of AKT and its associated proteins in chromatin ubiquitylation, and also indicate the AKT-Mel18-H2AK119ub axis as a novel prognostic biomarker and therapeutic target for cancer patients.


Assuntos
Neoplasias da Mama/genética , Carcinogênese/genética , Proteínas de Ciclo Celular/genética , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas c-akt/genética , Adulto , Idoso , Neoplasias da Mama/patologia , Proliferação de Células , Cromatina , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Histonas/genética , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Metástase Neoplásica , Intervalo Livre de Progressão , Ubiquitinação/genética
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