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1.
Nature ; 622(7984): 834-841, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37794190

RESUMEN

Although haemoglobin is a known carrier of oxygen in erythrocytes that functions to transport oxygen over a long range, its physiological roles outside erythrocytes are largely elusive1,2. Here we found that chondrocytes produced massive amounts of haemoglobin to form eosin-positive bodies in their cytoplasm. The haemoglobin body (Hedy) is a membraneless condensate characterized by phase separation. Production of haemoglobin in chondrocytes is controlled by hypoxia and is dependent on KLF1 rather than the HIF1/2α pathway. Deletion of haemoglobin in chondrocytes leads to Hedy loss along with severe hypoxia, enhanced glycolysis and extensive cell death in the centre of cartilaginous tissue, which is attributed to the loss of the Hedy-controlled oxygen supply under hypoxic conditions. These results demonstrate an extra-erythrocyte role of haemoglobin in chondrocytes, and uncover a heretofore unrecognized mechanism in which chondrocytes survive a hypoxic environment through Hedy.


Asunto(s)
Adaptación Fisiológica , Hipoxia de la Célula , Condrocitos , Hemoglobinas , Humanos , Cartílago Articular/citología , Cartílago Articular/metabolismo , Muerte Celular , Hipoxia de la Célula/fisiología , Condrocitos/metabolismo , Citoplasma/metabolismo , Eosina Amarillenta-(YS)/metabolismo , Eritrocitos/metabolismo , Glucólisis , Hemoglobinas/deficiencia , Hemoglobinas/genética , Hemoglobinas/metabolismo , Oxígeno/metabolismo
2.
Pharmacol Res ; : 107354, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39154671

RESUMEN

Breast cancer is a major public health concern worldwide, being the most commonly diagnosed cancer among women and a leading cause of cancer-related deaths. Recent studies have highlighted the significance of non-histone methylation in breast cancer, which modulates the activity, interaction, localization, and stability of target proteins. This regulation affects critical processes such as oncogenesis, tumor growth, proliferation, invasion, migration, and immune responses. This review delves into the enzymes responsible for non-histone methylation, such as protein arginine methyltransferases (PRMTs), lysine methyltransferases (KMTs), and demethylases, and explores their roles in breast cancer. By elucidating the molecular mechanisms and functional consequences of non-histone methylation, this review aims to provide insights into novel therapeutic strategies targeting these pathways. The therapeutic potential of targeting non-histone methylation to overcome drug resistance and enhance treatment efficacy in breast cancer is also discussed, highlighting promising avenues for future research and clinical applications.

3.
Bioorg Chem ; 134: 106463, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36924655

RESUMEN

Phenyldivinylsulfonamides emerged from a series of divinylsulfonamides, demonstrating their ability to effectively re-bridge disulfide bonds. This kind of linkers was attached to monomethyl auristatin E (MMAE) and further conjugated with a model antibody, trastuzumab. After optimization, the linker 20 can deliver stable and highly homogenous DAR (Drug-to-Antibody Ratio) four antibody-drug conjugates (ADCs). The method was also applicable for other IgG1 antibodies to obtain ADCs with controlled four payloads. Moreover, the MMAE-bearing ADC is potent, selective and efficacious against target cell lines.


Asunto(s)
Antineoplásicos , Inmunoconjugados , Inmunoconjugados/farmacología , Inmunoconjugados/química , Línea Celular Tumoral , Trastuzumab/química , Antineoplásicos/farmacología , Antineoplásicos/química
4.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37762128

RESUMEN

Up to 50% of hepatocellular carcinoma (HCC) is caused by hepatitis B virus (HBV) infection, and the surface protein of HBV is essential for the progression of HBV-related HCC. The expression of large HBV surface antigen (LHB) is presented in HBV-associated HCC tissues and is significantly associated with the development of HCC. Gene set enrichment analysis revealed that LHB overexpression regulates the cell cycle process. Excess LHB in HCC cells induced chronic endoplasmic reticulum (ER) stress and was significantly correlated with tumor growth in vivo. Cell cycle analysis showed that cell cycle progression from G1 to S phase was greatly enhanced in vitro. We identified intensive crosstalk between ER stress and cell cycle progression in HCC. As an important regulator of the G1/S checkpoint, p27 was transcriptionally upregulated by transcription factors ATF4 and XBP1s, downstream of the unfolded protein response pathway. Moreover, LHB-induced ER stress promoted internal ribosome-entry-site-mediated selective translation of p27, and E3 ubiquitin ligase HRD1-mediated p27 ubiquitination and degradation. Ultimately, the decrease in p27 protein levels reduced G1/S arrest and promoted the progress of HCC by regulating the cell cycle.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Hepatitis B/complicaciones , Virus de la Hepatitis B , Factores Inmunológicos , Neoplasias Hepáticas/genética , Proteínas de la Membrana , Respuesta de Proteína Desplegada
5.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1677-1686, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35347967

RESUMEN

Based on network pharmacology, the mechanism of Polygoni Cuspidati Rhizoma et Radix-Ligustri Lucidi Fructus(PL) combination against acute gouty arthritis(AGA) was explored and preliminarily verified by animal experiment. The chemical components and corresponding targets of PL were retrieved from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). The active components with oral bioavailability(OB)≥30% and drug-likeness(DL)≥0.18 were screened based on literature, and the related protein targets were collected. Then the protein targets were standardized with the help of UniProt database. The AGA-related targets were searched from GeneCards, NCBI, and DrugBank. The common targets of the disease and the medicinals were yielded by FunRich V3, and the protein-protein interaction(PPI) network was constructed to screen the key targets, followed by Gene Ontology(GO) term enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis of the key targets. Afterwards, some of the key targets were verified by sodium urate crystal-induced AGA mouse model. A total of 25 active components and 287 targets of PL, 811 targets of AGA, and 88 common targets were screened out. PPI network analysis showed that tumor necrosis factor(TNF), interleukin-6(IL-6), and interleukin-1ß(IL-1ß) may be the core targets of PL in the treatment of AGA. The key targets were mainly involved in 566 GO terms(P<0.05), including multiple biological processes such as inflammatory response and immune response. Moreover, they were related to 116 KEGG pathways and these pathways were involved in inflammation and immunity, mainly including NOD-like receptor signaling pathway and TNF signaling pathway. Animal experiment confirmed that PL can alleviate ankle swelling, improve abnormal gait, and down-regulate the protein expression of TNF-α, IL-6, and IL-1ß in AGA mice, indicating that PL can treat AGA through TNF-α, IL-6, and IL-1ß and the feasibility of network pharmacology to predict drug targets. This study preliminarily discussed the key targets and biological signaling pathways involved in the treatment of AGA with PL combination, which reflected the multi-pathway and multi-target action characteristics of Chinese medicine. Moreover, this study laid a scientific basis for research on the treatment of AGA with PL combination, as well as the mechanism of action.


Asunto(s)
Artritis Gotosa , Medicamentos Herbarios Chinos , Ligustrum , Animales , Artritis Gotosa/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Ratones , Farmacología en Red , Rizoma
6.
Mol Cancer ; 20(1): 79, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-34044846

RESUMEN

BACKGROUND: Somatic mutations are involved in hepatocellular carcinoma (HCC) progression, but the genetic mechanism associated to hepatocarcinogenesis remains poorly understood. We report that Eyes absent homolog 2 (EYA2) suppresses the HCC progression, while EYA2(A510E) mutation identified by exome sequencing attenuates the tumor-inhibiting effect of EYA2. METHODS: Whole-exome sequencing was performed on six pairs of human HCC primary tumors and matched adjacent tissues. Focusing on EYA2, expression level of EYA2 in human HCC samples was evaluated by quantitative real-time PCR, western blot and immunohistochemistry. Loss- and gain-of-function studies, hepatocyte-specific deletion of EYA2 (Eya2-/-) in mice and RNA sequencing analysis were used to explore the functional effect and mechanism of EYA2 on HCC cell growth and metastasis. EYA2 methylation status was evaluated using Sequenom MassARRAY and publicly available data analysis. RESULTS: A new somatic mutation p.Ala510Glu of EYA2 was identified in HCC tissues. The expression of EYA2 was down-regulated in HCC and associated with tumor size (P = 0.001), Barcelona Clinic Liver Cancer stage (P = 0.016) and tumor differentiation (P = 0.048). High level of EYA2 was correlated with a favorable prognosis in HCC patients (P = 0.003). Results from loss-of-function and gain-of-function experiments suggested that knockdown of EYA2 enhanced, while overexpression of EYA2 attenuated, the proliferation, clone formation, invasion, and migration of HCC cells in vitro. Delivery of EYA2 gene had a therapeutic effect on inhibition of orthotopic liver tumor in nude mice. However, EYA2(A510E) mutation led to protein degradation by unfolded protein response, thus weakening the inhibitory function of EYA2. Hepatocyte-specific deletion of EYA2 in mice dramatically promoted diethylnitrosamine-induced HCC development. EYA2 was also down-regulated in HCC by aberrant CpG methylation. Mechanically, EYA2 combined with DACH1 to transcriptionally regulate SOCS3 expression, thus suppressing the progression of HCC via SOCS3-mediated blockade of the JAK/STAT signaling pathway. CONCLUSIONS: In our study, we identified and validated EYA2 as a tumor suppressor gene in HCC, providing a new insight into HCC pathogenesis.


Asunto(s)
Carcinoma Hepatocelular/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Quinasas Janus/metabolismo , Neoplasias Hepáticas/patología , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Factores de Transcripción STAT/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas/metabolismo , Adulto , Anciano , Animales , Carcinoma Hepatocelular/metabolismo , Progresión de la Enfermedad , Femenino , Xenoinjertos , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Transducción de Señal/fisiología
7.
Nitric Oxide ; 107: 1-10, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33246103

RESUMEN

Phenotypic modulation of Corpus Cavernosum Smooth Muscle Cells (CCSMCs) is an important step in the development and progression of bilateral cavernous nerve injury induced erectile dysfunction (BCNI-ED). To investigate the effect of exogenous hydrogen sulfide (H2S) on the phenotypic modulation of CCSMCs in BCNI-ED rats, a total of 18 male Sprague-Dawley rats were equally divided into 3 groups, including sham-operated (Sham) group, BCNI group and BCNI treated with NaHS (BCNI + NaHS) group. The treated group received intraperitoneal injection of NaHS (100 µmol kg-1day-1) for 4 weeks starting day 1 postoperatively. Erectile function was measured by the ratio of intracavernous pressure (ICP)/mean arterial pressure (MAP), and relevant tissues were harvested for Immunohistochemistry, Hematoxylin and eosin (H&E), Masson's trichrome staining, H2S fluorescent probe WSP-1 and Western blot. The primary CCSMCs were isolated and pretreatment with NaHS before exposed to PDGF-BB (platelet-derived growth factor). Relative expression mRNA and protein of phenotypic biomarkers, RhoA, ROCK-1 and cell cycle proteins were detected. Cystathionine-ß-synthase (CBS) and cystathionine-γ-lyase (CSE), 3-mercaptopyruvate sulfurtransferase (3-MST) and H2S levels in penile tissue was significantly decreased in the BCNI group compared with the Sham group. Compared with the BCNI group, administration of NaHS significantly increased the ratio of ICP/MAP, ratio of smooth muscle to collagen, expressions of a-SMA, calponin and decreased the expression of OPN, collagen-I, RhoA, ROCK1 in the penile tissue. PDGF-BB-treated CCSMCs exhibited higher expression of OPN, RhoA, ROCK1, and lower α-SMA, calponin, which were attenuated by NaHS pretreatment. NaHS suppressed RhoA/ROCK activity and decreased the expression of CDK2, Cyclin E1, while increased the expression of P27kip1 induced by PDGF-BB in CCSMCs. Taken together, this study indicated that exogenous H2S inhibited the phenotypic modulation of CCSMCs by suppressing RhoA/ROCK1 signaling and affecting its downstream factor, CDK2, Cyclin E1, P27kip1, thereby improved BCNI rat erectile function.


Asunto(s)
Disfunción Eréctil/tratamiento farmacológico , Sulfuro de Hidrógeno/uso terapéutico , Músculo Liso/efectos de los fármacos , Erección Peniana/efectos de los fármacos , Pene/efectos de los fármacos , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Quinasa 2 Dependiente de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Ciclinas/metabolismo , Disfunción Eréctil/etiología , Masculino , Músculo Liso/citología , Miocitos del Músculo Liso/efectos de los fármacos , Pene/citología , Pene/inervación , Traumatismos de los Nervios Periféricos/complicaciones , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Proteínas de Unión al GTP rho/metabolismo , Quinasas Asociadas a rho/metabolismo
8.
Bioorg Med Chem ; 51: 116497, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34794002

RESUMEN

Antibody-drug conjugates (ADCs) have emerging as efficient agents to target deliver cytotoxic drugs and reduce their off-target side effects. Triptolide has attracted attention to be used in ADC development. Herein, three rationally designed triptolide drug-linkers have been synthesized for use in site-specific construction of ADCs. Carbamates that were supposed to be more stable than carbonates were introduced to attach triptolide to the linkers. PEG and discrete PEG chains were incorporated to improve the hydrophilicity of drug-linkers. The ADCs were finally site-specifically prepared by conjugation of the drug-linkers to trastuzumab through disulfide re-bridging approach. The preliminary anti-tumor activities of these ADCs were evaluated and they displayed high potencies against HER2-targeted cancer in vitro and in vivo.


Asunto(s)
Antineoplásicos/farmacología , Diterpenos/farmacología , Inmunoconjugados/farmacología , Fenantrenos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Diterpenos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Epoxi/química , Compuestos Epoxi/farmacología , Humanos , Inmunoconjugados/química , Masculino , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/patología , Ratones , Estructura Molecular , Fenantrenos/química , Relación Estructura-Actividad
9.
Perfusion ; 36(2): 122-129, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32522095

RESUMEN

BACKGROUND: Periprocedural myocardial infarction is a common complication following percutaneous coronary intervention. The present study was conducted with an aim to compare the safety and efficacy of loading doses of ticagrelor versus clopidogrel in preventing periprocedural myocardial infarction in Asian patients with acute coronary syndrome undergoing elective percutaneous coronary intervention. METHODS: A total of 114 patients with acute coronary syndrome undergoing elective percutaneous coronary intervention were assigned to clopidogrel group (n = 57, the loading and maintenance doses were 300 and 75 mg qd for clopidogrel, and 300 and 100 mg qd for aspirin), or ticagrelor group (n = 57, the loading and maintenance doses were 180 and 90 mg bid for ticagrelor, and 300 and 100 mg qd for aspirin). Cardiac biomarkers were measured before, 8 hours, and 24 hours after percutaneous coronary intervention. The percutaneous coronary intervention-related periprocedural myocardial infarction was defined according to the fourth universal definition of myocardial infarction (2018). RESULTS: The overall incidence of percutaneous coronary intervention-related periprocedural myocardial infarction was 21.1%. The ticagrelor group showed a significantly lower incidence of periprocedural myocardial infarction (12.3% vs 29.8%, p = 0.022) and numerically lower bleeding events (3.5% vs 8.8%, p = 0.242) as compared with clopidogrel group. No patient had major adverse cardiovascular events during the 1-month follow-up. The levels of high-sensitivity C-reactive protein did not differ significantly between the two groups (p > 0.05), indicating that the benefits of ticagrelor were not from its anti-inflammatory effects. Multivariable analysis showed that the use of ticagrelor (odds ratio: 0.50; 95% confidence interval: 0.29-0.87; p = 0.014) and number of stents (odds ratio: 2.75; 95% confidence interval: 1.25-6.06; p = 0.012) were independent predictors of periprocedural myocardial infarction. CONCLUSION: Pretreatment with a loading dose of ticagrelor seems to be superior in reducing the incidence of percutaneous coronary intervention-related periprocedural myocardial infarction in Asian patients with acute coronary syndrome as compared with clopidogrel.


Asunto(s)
Síndrome Coronario Agudo , Clopidogrel/administración & dosificación , Infarto del Miocardio , Intervención Coronaria Percutánea , Ticagrelor/administración & dosificación , Síndrome Coronario Agudo/tratamiento farmacológico , Humanos , Infarto del Miocardio/etiología , Infarto del Miocardio/prevención & control , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/administración & dosificación , Resultado del Tratamiento
10.
Anal Chem ; 92(20): 13702-13710, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32955856

RESUMEN

We describe an efficient decision tree searching strategy (DTSS) to boost the identification of cross-linked peptides. The DTSS approach allows the identification of a wealth of complementary information to facilitate the construction of more protein-protein interaction networks for human cell lysate, which was tested by the use of a recently reported cross-linking data set (ACS Cent. Sci. 2019, 5, 1514-1522). A variant of the PhoX-linker, named pDSPE, was synthesized and applied to cross-link Escherichia coli cell lysate to demonstrate that the acquisition of doubly charged ions can significantly improve identification results. The method can be seamlessly integrated to other search engines to maximize the number of identified cross-links.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Árboles de Decisión , Espectrometría de Masas/métodos , Péptidos/análisis , Cromatografía Líquida de Alta Presión , Escherichia coli/metabolismo , Péptidos/química , Péptidos/metabolismo , Ácidos Fosforosos/química , Mapas de Interacción de Proteínas
11.
Am J Pathol ; 189(8): 1637-1653, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31345467

RESUMEN

Cholangiocarcinoma (CCA) is a malignant cancer that is associated with high mortality rates. The relationship between laminin γ 2 chain gene (LAMC2) and epidermal growth factor receptor (EGFR) has been previously documented in gastric cancer and oral squamous cell carcinoma. This study investigates the role of LAMC2 in epithelial-mesenchymal transition (EMT) and angiogenesis in CCA and explores the underlying mechanism(s). Differentially expressed genes related to CCA were initially screened using a microarray analysis, and the interaction between LAMC2 and the EGFR signaling pathway was identified. To determine the regulatory effects of LAMC2 on CCA progression, LAMC2 was silenced or overexpressed and the EGFR signaling pathway was activated or blocked. Subsequently, the regulation effects of LAMC2 were evaluated on the expression of EMT markers, invasion and migration of CCA cells, as well as microvessel density in nude mice. Microarray analysis demonstrated that highly expressed LAMC2 is linked to CCA development, which involves the EGFR signaling pathway. When LAMC2 expression was increased, the EGFR signaling pathway and EMT were activated in CCA tissues. Silencing of LAMC2 as well as EGFR signaling pathway inhibition led to suppression of EMT, cell invasion, and migration abilities in vitro, as well as angiogenesis in vivo. This study demonstrates that LAMC2 silencing suppresses the activity of the EGFR signaling pathway, thus functioning as a tumor suppressor in CCA.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Transición Epitelial-Mesenquimal , Laminina/metabolismo , Neovascularización Patológica/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/metabolismo , Adulto , Anciano , Animales , Neoplasias de los Conductos Biliares/irrigación sanguínea , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Línea Celular Tumoral , Colangiocarcinoma/irrigación sanguínea , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Receptores ErbB/metabolismo , Femenino , Silenciador del Gen , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Neovascularización Patológica/patología
12.
Am J Pathol ; 189(5): 1065-1076, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30735628

RESUMEN

It has been reported that disorders of epigenetic modulation play a critical role in carcinogenesis. Methyl-CpG binding domain protein 2 (MBD2) is known to act as an epigenetic modulator in various types of tumors; however, the role of MBD2 in lung adenocarcinoma (LUAD) remains unclear. Herein, we demonstrated the down-regulation of MBD2 in LUAD compared with adjacent nontumor tissues. The down-regulation of MBD2 in LUAD was correlated with metastasis and poor survival. In addition, MBD2 inhibited tumor metastasis by maintaining the expression of the miR-200s, which suppressed the invasive properties of tumors. Also, MBD2 positively correlated with 5-hydroxymethylcytosine content in the promoter of miR-200s. The conventional view is that MBD2 acts as a transcriptional suppressor. However, the data revealed that MBD2 may act as a transcriptional activator by recruiting 10 to 11 translocation 1 (TET1) and forming a chromatin-remodeling complex. The MBD2-TET1 complex locates to the TET1 promoter and removes the methyl residues in this region, thereby activating TET1 transcription. TET1 also acted as a tumor suppressor in LUAD. Taken together, the data demonstrate the correlation between MBD2, miR-200s, and TET1, and tumor suppressive effect of MBD2 through up-regulation of TET1 and the miR-200s.


Asunto(s)
Adenocarcinoma del Pulmón/patología , Biomarcadores de Tumor/genética , Proteínas de Unión al ADN/metabolismo , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Oxigenasas de Función Mixta/genética , Proteínas Proto-Oncogénicas/genética , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Apoptosis , Movimiento Celular , Proliferación Celular , Metilación de ADN , Proteínas de Unión al ADN/genética , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Pronóstico , Regiones Promotoras Genéticas , Células Tumorales Cultivadas
13.
Blood ; 131(10): 1111-1121, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29352039

RESUMEN

Effective vaccines against malaria caused by Plasmodium falciparum are still lacking, and the molecular mechanism of the host-parasite interaction is not fully understood. Here we demonstrate that the interaction of RAP2, a parasite-secreted rhoptry protein that functions in the parasitophorous vacuole formation stage of the invasion, and CD147 on the host erythrocyte is essential for erythrocyte invasion by P falciparum and is independent from all previously identified interactions involved. Importantly, the blockade of the CD147-RAP2 interaction by HP6H8, a humanized CD147 antibody, completely abolished the parasite invasion with both cure and preventative functions in a humanized mouse model. Together with its long half-life on human red blood cells and its safety profile in cynomolgus monkeys, HP6H8 is the first antibody that offers an advantageous approach by targeting a more conserved late-stage parasite ligand for preventing as well as treating severe malaria.


Asunto(s)
Basigina/metabolismo , Eritrocitos/metabolismo , Malaria Falciparum/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Unión al GTP rap/metabolismo , Animales , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Antiprotozoarios/farmacología , Eritrocitos/parasitología , Eritrocitos/patología , Humanos , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID
14.
J Pathol ; 249(2): 255-267, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31215640

RESUMEN

The γ-secretase complex is a presenilin-dependent aspartyl protease involved in the intramembranous cleavage of various type I transmembrane proteins. As a type I transmembrane protein, CD147 is highly expressed in hepatoma cells and promotes cell proliferation, migration, and invasion. However, the direct underlying mechanism of how CD147 promotes cancer cell proliferation is unknown. Here, we demonstrated that CD147 undergoes an intramembranous cleavage by the γ-secretase at lysine 231 to release its intracellular domains (ICDs). The nuclear translocation of the CD147ICD regulated Notch1 expression by directly binding to the NOTCH1 promoter and promoted the activation of the Notch signaling pathway. Simultaneously, overexpression of CD147ICD promoted cancer cell proliferation via Notch1 signaling. In 102 cases of human hepatocellular carcinoma (HCC) tissues, patients with a high positive rate of nuclear CD147ICD expression had a significantly poor overall survival compared with patients with a low positive rate of nuclear CD147ICD expression. We confirmed that nuclear CD147ICD predicted a poor prognosis in human HCC. The combined therapy of the γ-secretase complex inhibitor and CD147-directed antibody showed better efficacy than monotherapy in orthotopic transplantation HCC mouse models. In conclusion, CD147 is cleaved by the γ-secretase and releases CD147ICD to the cell nucleus, promoting Notch1 expression via direct binding to the NOTCH1 promoter. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/metabolismo , Basigina/metabolismo , Carcinoma Hepatocelular/enzimología , Proliferación Celular , Neoplasias Hepáticas/enzimología , Receptor Notch1/metabolismo , Transporte Activo de Núcleo Celular , Animales , Antineoplásicos Inmunológicos/farmacología , Basigina/antagonistas & inhibidores , Basigina/genética , Sitios de Unión , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Regiones Promotoras Genéticas , Proteolisis , Receptor Notch1/genética , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Bioorg Med Chem ; 28(23): 115793, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33039798

RESUMEN

Methods that site-specifically attach payloads to an antibody with controlled DAR (Drug-Antibody Ratio) are highly desirable for the generation of homogeneous antibody-drug conjugates (ADCs). We describe the use of N-phenyl-divinylsulfonamide scaffold as a linker platform to site-specifically construct homogeneous DAR four ADCs through a disulfide re-bridging approach. Several monomethyl auristatin E (MMAE)-linkers were synthesized and the drug-linkers that contain electron-donating groups on the phenyl of the linker showed high stability. Her2-targeted MMAE-linker-herceptin and EGFR targeted MMAE-linker-cetuximab conjugates were prepared. The conjugates demonstrated high efficacy and selectivity for killing target-positive cancer cells in vitro. The EGFR-targeted conjugates also showed significant antitumor activities in vivo.


Asunto(s)
Inmunoconjugados/química , Sulfonamidas/química , Aminobenzoatos/química , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cetuximab/química , Reacción de Cicloadición , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Neoplasias/tratamiento farmacológico , Oligopéptidos/química , Trasplante Heterólogo , Trastuzumab/química
16.
Cancer Sci ; 110(8): 2368-2377, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31222863

RESUMEN

Macrophages are essential inflammatory cells which regulate the features of immune reactions within tumors. Many studies have reported their regulatory roles in immunity through cytokines and cell signaling. However, relatively few studies have focused on their metabolic features and mechanisms. We aimed to determine the signaling pathway regulating cell metabolism and the mechanism related to the regulation of human tumor-associated macrophages (TAMs) in gastric cancer (GC). Tumor-infiltrated macrophages were isolated from human GC tissues using magnetic beads, gene transcription was determined by real-time PCR, protein expression was monitored using western blots, metabolites were determined using HPLC, and transcriptional regulation was analyzed by the luciferase-based reporter gene system. A significant decrease in microRNA (miR)-30c and an increase in regulated in development and DNA damage responses 1 (REDD1) were detected in human GC TAMs, the transcription of miR-30c was negatively correlated with REDD1. MicroRNA-30c expression was suppressed by hypoxia-inducible factor-1α activation and related to decreased mTOR activity as well as glycolysis in human GC TAMs. Hypoxia-regulated miR-30c downregulated REDD-1 expression by targeting its 3'UTR. Overexpression of miR-30c or restored mTOR activity in macrophages with miR-30cLow expression promoted M1 macrophage differentiation and function in TAMs. Therefore, hypoxia in the human GC microenvironment suppressed the expression of miR-30c, and decreased mTOR activity as well as glycolysis in GC TAMs, thus inhibiting M1 differentiation and function. These results provide a novel metabolic strategy for tumor microenvironment-based therapy.


Asunto(s)
Glucólisis/genética , Hipoxia/genética , Macrófagos/patología , MicroARNs/genética , Neoplasias Gástricas/genética , Serina-Treonina Quinasas TOR/genética , Regiones no Traducidas 3'/genética , Diferenciación Celular , Línea Celular , Proliferación Celular/genética , Regulación hacia Abajo/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Hipoxia/patología , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Masculino , Persona de Mediana Edad , Transducción de Señal/genética , Neoplasias Gástricas/patología , Factores de Transcripción/genética , Transcripción Genética/genética , Microambiente Tumoral/genética
17.
Exp Cell Res ; 363(1): 84-94, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29289595

RESUMEN

Autophagy is a highly dynamic process characterized with the term of autophagic flux. In the present study, we developed a quantifiable luciferase reporter system to measure the capacity as well as the dynamics of autophagic flux. Briefly, a luciferase variant of Luc2p was fused with p62/SQSTM1 or its UBA domain deletion mutant (p62ΔU) and transfected into cells. The expressed Luc2p-p62 fusion protein was primarily degraded via autophagy, while Luc2p-p62ΔU was employed as a normalization control due to its resistance to autophagic degradation. The luciferase activity of the lysates from two parallel populations of glioma cells expressing either Luc2p-p62 or Luc2p-p62ΔU was determined and the ratio of Luc2p-p62ΔU/Luc2p-p62 was used to assay the autophagic flux. By this approach, the induction of autophagy was manifested as an increased Luc2p-p62ΔU/Luc2p-p62 ratio, which could be neutralized by autophagy inhibitors or knockdown of ATG5. The performance of our autophagic flux detection system was comparable to a recently reported GFP-LC3-RFP-LC3ΔG probe. We tested the system in TMZ treated glioma cells, and found that coadministration of chloroquine to attenuate cellular autophagic flux significantly improved the TMZ efficacy by triggering more early apoptosis. Collectively, our luciferase-based autophagic flux assay may serve as a useful alternative yet sensitive method for autophagic flux detection in tumor cells.


Asunto(s)
Autofagia/fisiología , Glioma/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína Sequestosoma-1/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis/fisiología , Línea Celular Tumoral , Supervivencia Celular/fisiología , Humanos , Luciferasas/metabolismo
18.
Artículo en Inglés | MEDLINE | ID: mdl-31279678

RESUMEN

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

19.
Small ; : e1800762, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30019826

RESUMEN

CO2 conversion into value-added chemical fuels driven by solar energy is an intriguing approach to address the current and future demand of energy supply. Currently, most reported surface-sensitized heterogeneous photocatalysts present poor activity and selectivity under visible light irradiation. Here, photosensitized porous metallic and magnetic 1200 CoC composites (PMMCoCC-1200) are coupled with a [Ru(bpy)3 ]Cl2 photosensitizer to efficiently reduce CO2 under visible-light irradiation in a selective and sustainable way. As a result, the CO production reaches a high yield of 1258.30 µL with selectivity of 64.21% in 6 h, superior to most reported heterogeneous photocatalysts. Systematic investigation demonstrates that the central metal cobalt is the active site for activating the adsorbed CO2 molecules and the surficial graphite carbon coating on cobalt metal is crucial for transferring the electrons from the triplet metal-to-ligand charge transfer of the photosensitizer Ru(bpy)32+ , which gives rise to significant enhancement for CO2 reduction efficiency. The fast electron injection from the excited Ru(bpy)32+ to PMMCoCC-1200 and the slow backward charge recombination result in a long-lived, charge-separated state for CO2 reduction. More impressively, the long-time stability and easy magnetic recycling ability of this metallic photocatalyst offer more benefits to the photocatalytic field.

20.
Pediatr Dermatol ; 35(2): 265-267, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29436008

RESUMEN

This retrospective study aimed to identify factors that predict treatment response in a cohort of Asian children with vitiligo. Shorter duration of vitiligo was associated with better repigmentation. Patients with focal vitiligo of short duration have a good chance of achieving repigmentation with topical agents alone.


Asunto(s)
Inhibidores de la Calcineurina/uso terapéutico , Glucocorticoides/uso terapéutico , Fototerapia/métodos , Prednisolona/uso terapéutico , Vitíligo/terapia , Administración Tópica , Pueblo Asiatico , Niño , Preescolar , Terapia Combinada , Femenino , Humanos , Masculino , Estudios Retrospectivos , Pigmentación de la Piel/efectos de los fármacos , Resultado del Tratamiento
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