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1.
Environ Toxicol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884142

RESUMO

Environmental antineoplastics such as sorafenib may pose a risk to humans through water recycling, and the increased risk of cardiotoxicity is a clinical issue in sorafenib users. Thus, developing strategies to prevent sorafenib cardiotoxicity is an urgent work. Empagliflozin, as a sodium-glucose co-transporter-2 (SGLT2) inhibitor for type 2 diabetes control, has been approved for heart failure therapy. Still, its cardioprotective effect in the experimental model of sorafenib cardiotoxicity has not yet been reported. Real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to study the effect of sorafenib exposure on cardiac SGLT2 expression. The impact of empagliflozin on cell viability was investigated in the sorafenib-treated cardiomyocytes using Alamar blue assay. Immunoblot analysis was employed to delineate the effect of sorafenib and empagliflozin on ferroptosis/proinflammatory signaling in cardiomyocytes. Ferroptosis/DNA damage/fibrosis/inflammation of myocardial tissues was studied in mice with a 28-day sorafenib ± empagliflozin treatment using histological analyses. Sorafenib exposure significantly promoted SGLT2 upregulation in cardiomyocytes and mouse hearts. Empagliflozin treatment significantly attenuated the sorafenib-induced cytotoxicity/DNA damage/fibrosis in cardiomyocytes and mouse hearts. Moreover, GPX4/xCT-dependent ferroptosis as an inducer for releasing high mobility group box 1 (HMGB1) was also blocked by empagliflozin administration in the sorafenib-treated cardiomyocytes and myocardial tissues. Furthermore, empagliflozin treatment significantly inhibited the sorafenib-promoted NFκB/HMGB1 axis in cardiomyocytes and myocardial tissues, and sorafenib-stimulated proinflammatory signaling (TNF-α/IL-1ß/IL-6) was repressed by empagliflozin administration. Finally, empagliflozin treatment significantly attenuated the sorafenib-promoted macrophage recruitments in mouse hearts. In conclusion, empagliflozin may act as a cardioprotective agent for humans under sorafenib exposure by modulating ferroptosis/DNA damage/fibrosis/inflammation. However, further clinical evidence is required to support this preclinical finding.

2.
BMC Med Educ ; 24(1): 132, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341547

RESUMO

BACKGROUND: Longitudinal integrated clerkships (LICs) and traditional block rotations (TBRs) employ different designs that provide various learning experiences for students. In this study, we explored students' clinical participation and interpersonal interactions in LICs and TBRs at 2 metropolitan hospitals in Taiwan. METHODS: In April 2018, we enrolled 15 LIC and 29 TBR students. We conducted a cross-sectional survey which required the students to outline a typical daily schedule during their internal medicine rotations and draw an ecomap of the clinical team members. With the patient in the center as a reference, the size of each circle in an ecomap indicated the importance of the member; the distances and number of connecting lines between two circles represented the relationship and frequency of interaction, respectively, between the corresponding members. We analyzed the results and compared the responses of the LIC and TBR students. RESULTS: The LIC students spent more time on direct patient care and in the outpatient clinic/operation room, whereas the TBR students participated more in educational activities and in observation behind their seniors. In the ecomap analysis, the LIC students had a closer relationship with attending physicians and had better interactions with patients and preceptors than did the TBR students. Conversely, the TBR students felt closer to and interacted more frequently with interns and residents. CONCLUSIONS: The LIC students had more opportunities to care for patients directly and engaged in interactions with patients and attending physicians more frequently than did the TBR students. TRIAL REGISTRATION: Ethical approval for the study was obtained from the Institutional Review Board of Tri-Service General Hospital (TSGHIRB 2-106-05-018).


Assuntos
Estágio Clínico , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Taiwan , Estudos Transversais , Estágio Clínico/métodos
3.
J Microbiol Immunol Infect ; 57(2): 309-319, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38199822

RESUMO

INTRODUCTION: Early enteral nutrition (EN) is a nutritional strategy for reducing the incidence of in-hospital infections. However, the benefits of early EN, under targeted temperature management (TTM) in patients with out-of-hospital cardiac arrest (OHCA), remain unclear. We aimed to evaluate the effect of early EN on the infective complications of OHCA patients who underwent TTM. METHODS: We retrospectively searched the clinical databases of two adult emergency tertiary referral hospitals in southern Taiwan and identified patients admitted for OHCA who underwent TTM between 2017 and 2022. The 85 enrolled patients were divided into two groups based on timing: early EN (EN within 48 h of admission) and delayed EN (EN > 48 h after admission). Clinical outcomes of 7-day infective complications between the two groups were analyzed. RESULTS: Early EN was provided to 57 (67 %) of 85 patients and delayed EN was provided to the remaining 28 (33 %) patients. No significant differences in baseline patient characteristics were observed between the two groups. In addition, no differences in clinical outcomes were observed, except that the early EN group had a lower 7-day bacteremia rate (5.3 % vs. 26.9 %, p = 0.013). Gram-negative bacteria were the major pathogen among the 7-day infective complications. CONCLUSION: In OHCA patients treated with TTM, early EN was associated with a lower 7-day bacteremia rate. Furthermore, the application of early EN in this population was well tolerated without significant adverse events.


Assuntos
Bacteriemia , Parada Cardíaca Extra-Hospitalar , Humanos , Nutrição Enteral , Estudos Retrospectivos , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/complicações , Temperatura , Bacteriemia/complicações
4.
Gene ; 865: 147331, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36871674

RESUMO

Slow skeletal muscle troponin T (TNNT1) as a poor prognostic indicator is upregulated in colon and breast cancers. However, the role of TNNT1 in the disease prognosis and biological functions of hepatocellular carcinoma (HCC) is still unclear. The Cancer Genome Atlas (TCGA), real-time quantitative RT-PCR (qRT-PCR), immunoblot, and immunohistochemical analyses were applied to evaluate the TNNT1 expression of human HCC. The impact of TNNT1 levels on disease progression and survival outcome was studied using TCGA analysis. Moreover, the bioinformatics analysis and HCC cell culture were used to investigate the biological functions of TNNT1. Besides, the immunoblot analysis and enzyme-linked immunosorbent assay (ELISA) were used to detect the extracellular TNNT1 of HCC cells and circulating TNNT1 of HCC patients, respectively. The effect of TNNT1 neutralization on oncogenic behaviors and signaling was further validated in the cultured hepatoma cells. In this study, tumoral and blood TNNT1 was upregulated in HCC patients based on the analyses using bioinformatics, fresh tissues, paraffin sections, and serum. From the multiple bioinformatics tools, the TNNT1 overexpression was associated with advanced stage, high grade, metastasis, vascular invasion, recurrence, and poor survival outcome in HCC patients. By the cell culture and TCGA analyses, TNNT1 expression and release were positively correlated with epithelial-mesenchymal transition (EMT) processes in HCC tissues and cells. Moreover, TNNT1 neutralization suppressed oncogenic behaviors and EMT in hepatoma cells. In conclusion, TNNT1 may serve as a non-invasive biomarker and drug target for HCC management. This research finding may provide a new insight for HCC diagnosis and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Músculo Esquelético/metabolismo , Prognóstico , Troponina T/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-36981892

RESUMO

To investigate the relationship between chronic liver disease and tendon disorder, a retrospective cohort study was conducted using the Kaohsiung Veterans General Hospital database. Patients >18 years with newly diagnosed liver disease and with at least a two-year follow-up in the hospital were included. An equal number of 20,479 cases were enrolled in both the liver-disease and non-liver-disease groups using a propensity score matching method. Disease was defined using ICD-9 or ICD-10 codes. The primary outcome was the development of tendon disorder. Demographic characteristics, comorbidities, use of tendon-toxic drugs, and status of HBV/HCV infection were included for analysis. The results showed 348 (1.7%) and 219 (1.1%) individuals developed tendon disorder in the chronic liver disease group and non-liver-disease group. Concomitant use of glucocorticoids and statins may have further raised the risk of tendon disorder in the liver disease group. The co-existence of HBV/HCV infection did not increase the risk of tendon disorder in the patients with liver disease. Considering these findings, physicians should be more aware of tendon issues in advance, and a prophylactic strategy should be adopted in patients with chronic liver disease.


Assuntos
Hepatite C , Hepatopatias , Humanos , Estudos Retrospectivos , Taiwan/epidemiologia , Hepatopatias/complicações , Hepatopatias/epidemiologia , Tendões
6.
Environ Pollut ; 327: 121476, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997141

RESUMO

Plasticizers are considered as environmental pollution released from medical devices and increased potential oncogenic risks in clinical therapy. Our previous studies have shown that long-term exposure to di-ethylhexyl phthalate (DEHP)/mono-ethylhexyl phthalate (MEHP) promotes chemotherapeutic drug resistance in colorectal cancer. In this study, we investigated the alteration of glycosylation in colorectal cancer following long-term plasticizers exposure. First, we determined the profiles of cell surface N-glycomes by using mass spectrometry and found out the alterations of α2,8-linkages glycans. Next, we analyzed the correlation between serum DEHP/MEHP levels and ST8SIA6 expression from matched tissues in total 110 colorectal cancer patients. Moreover, clinical specimens and TCGA database were used to analyze the expression of ST8SIA6 in advanced stage of cancer. Finally, we showed that ST8SIA6 regulated stemness in vitro and in vivo. Our results revealed long-term DEHP/MEHP exposure significantly caused cancer patients with poorer survival outcome and attenuated the expression of ST8SIA6 in cancer cells and tissue samples. As expected, silencing of ST8SIA6 promoted cancer stemness and tumorigenicity by upregulating stemness-associated proteins. In addition, the cell viability assay showed enhanced drug resistance in ST8SIA6 silencing cells treated with irinotecan. Besides, ST8SIA6 was downregulated in the advanced stage and positively correlated with tumor recurrence in colorectal cancer. Our results imply that ST8SIA6 potentially plays an important role in oncogenic effects with long-term phthalates exposure.


Assuntos
Neoplasias Colorretais , Dietilexilftalato , Humanos , Plastificantes/análise , Dietilexilftalato/análise , Glicosilação , Sialiltransferases/metabolismo
7.
Science ; 376(6597): 1074-1079, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35653481

RESUMO

Aminoacyl transfer RNA (tRNA) synthetases (aaRSs) are attractive drug targets, and we present class I and II aaRSs as previously unrecognized targets for adenosine 5'-monophosphate-mimicking nucleoside sulfamates. The target enzyme catalyzes the formation of an inhibitory amino acid-sulfamate conjugate through a reaction-hijacking mechanism. We identified adenosine 5'-sulfamate as a broad-specificity compound that hijacks a range of aaRSs and ML901 as a specific reagent a specific reagent that hijacks a single aaRS in the malaria parasite Plasmodium falciparum, namely tyrosine RS (PfYRS). ML901 exerts whole-life-cycle-killing activity with low nanomolar potency and single-dose efficacy in a mouse model of malaria. X-ray crystallographic studies of plasmodium and human YRSs reveal differential flexibility of a loop over the catalytic site that underpins differential susceptibility to reaction hijacking by ML901.


Assuntos
Antimaláricos , Malária Falciparum , Terapia de Alvo Molecular , Plasmodium falciparum , Biossíntese de Proteínas , Proteínas de Protozoários , Tirosina-tRNA Ligase , Adenosina/análogos & derivados , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Cristalografia por Raios X , Humanos , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Camundongos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Biossíntese de Proteínas/efeitos dos fármacos , Conformação Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Ácidos Sulfônicos/química , Tirosina-tRNA Ligase/química , Tirosina-tRNA Ligase/metabolismo
8.
Genes (Basel) ; 13(4)2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35456435

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common RCC subtype with a high mortality. It has been reported that delta-like 1 homologue (DLK1) participates in the tumor microenvironmental remodeling of ccRCC, but the relationship between delta-like 2 homologue (DLK2, a DLK1 homologue) and ccRCC is still unclear. Thus, this study aims to investigate the role of DLK2 in the biological function and disease prognosis of ccRCC using bioinformatics analysis. The TNMplot database showed that DLK2 was upregulated in ccRCC tissues. From the UALCAN analysis, the overexpression of DLK2 was associated with advanced stage and high grade in ccRCC. Moreover, the Kaplan-Meier plotter (KM Plotter) database showed that DLK2 upregulation was associated with poor survival outcome in ccRCC. By the LinkedOmics analysis, DLK2 signaling may participated in the modulation of ccRCC extracellular matrix (ECM), cell metabolism, ribosome biogenesis, TGF-ß signaling and Notch pathway. Besides, Tumor Immune Estimation Resource (TIMER) analysis showed that the macrophage and CD8+ T cell infiltrations were associated with good prognosis in ccRCC patients. Finally, DLK2 overexpression was associated with the reduced macrophage recruitments and the M1-M2 polarization of macrophage in ccRCC tissues. Together, DLK2 may acts as a novel biomarker, even therapeutic target in ccRCC. However, this study lacks experimental validation, and further studies are required to support this viewpoint.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Biologia Computacional , Feminino , Humanos , Neoplasias Renais/metabolismo , Masculino , Prognóstico
9.
Artigo em Inglês | MEDLINE | ID: mdl-35457390

RESUMO

This cohort study aimed to investigate the association between steroid injections for shoulder diseases and the increased incidence of cuff tendon tears. The Kaohsiung Veterans General Hospital clinical database was used in this study. Patients were enrolled using the corresponding diagnostic codes for shoulder diseases. Patients who received steroid injections were included in the case group, and those without steroid injections were included in the control group. The outcome measure was the occurrence of cuff tendon tears during the study period. Adjusted hazard ratios for outcomes were calculated using Cox regression analysis adjusted for sex, age, and comorbidities. Of the 1025 patients with shoulder disease, 205 were in the case group and 820 were in the control group. The incidence of cuff tendon tears was 9.8% in patients who received steroid injections (p < 0.001). The adjusted hazard ratios for steroid injections, smoking, and chronic liver disease were 7.44 (p < 0.001), 2.40 (p = 0.046), 3.25 (p = 0.007), respectively. Steroid injections on the shoulder were associated with a raised risk of cuff tendon tears by 7.44 times compared to non-injection. The incidence of cuff tendon tears increased by 3.25 times with concurrent chronic liver disease and by 2.4 times with smoking.


Assuntos
Lesões do Manguito Rotador , Estudos de Coortes , Humanos , Lesões do Manguito Rotador/epidemiologia , Esteroides/efeitos adversos , Tendões
10.
J Pers Med ; 12(3)2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35330401

RESUMO

Sialylation of glycoproteins is modified by distinct sialyltransferases such as ST3Gal, ST6Gal, ST6GalNAc, or ST8SIA with α2,3-, α2,6-, or α2,8-linkages. Alteration of these sialyltransferases causing aberrant sialylation is associated with the progression of colon cancer. However, among the ST8- sialyltransferases, the role of ST8SIA6 in colon cancer remains poorly understood. In this study, we explored the involvement of ST8SIA6 in colon cancer using multiple gene databases. The relationship between ST8SIA6 expression and tumor stages/grades was investigated by UALCAN analysis, and Kaplan-Meier Plotter analysis was used to analyze the expression of ST8SIA6 on the survival outcome of colon cancer patients. Moreover, the biological functions of ST8SIA6 in colon cancer were explored using LinkedOmics and cancer cell metabolism gene DB. Finally, TIMER and TISMO analyses were used to delineate ST8SIA6 levels in tumor immunity and immunotherapy responses, respectively. ST8SIA6 downregulation was associated with an advanced stage and poorly differentiated grade; however, ST8SIA6 expression did not affect the survival outcomes in patients with colon cancer. Gene ontology analysis suggested that ST8SIA6 participates in cell surface adhesion, angiogenesis, and membrane vesicle trafficking. In addition, ST8SIA6 levels affected immunocyte infiltration and immunotherapy responses in colon cancer. Collectively, these results suggest that ST8SIA6 may serve as a novel therapeutic target towards personalized medicine for colon cancer.

11.
Clin Case Rep ; 10(1): e05285, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35035967

RESUMO

We described an 87-year-old man who presented with fever and hemoptysis. Nosocomial pneumonia was initially suspected. However, the patient had worsening hemoptysis despite defervescence. Chest computed tomography disclosed ruptured thoracic aortic aneurysm. Emergent surgery was then commenced for adequate treatment.

12.
J Interv Card Electrophysiol ; 64(3): 587-595, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34468890

RESUMO

PURPOSE: The relationship between height and incident atrial fibrillation (AF) has recently been demonstrated. We aimed to evaluate the impact of height on outcomes of ablation in patients with drug-refractory symptomatic paroxysmal AF (PAF). METHODS: A total of 689 patients (470 males; age, 53.0 ± 11.7 years) with symptomatic paroxysmal AF receiving index catheter ablation (CA) between 2003 and 2013 were enrolled in this study. The baseline characteristics, ablation, and follow-up results were evaluated. The patients were categorized according to the quartiles of height for each sex. RESULTS: Patients in the lower quartiles of height had a lower incidence of AF recurrence (log-rank p = 0.022). Height in female patients was strongly associated with AF recurrence (p = 0.027) after an index ablation in the 6.33 ± 4.32 years of follow-up. Female patients > 159 cm in height had a higher likelihood of AF recurrence after index CA (HR = 2.01, 95% CI: 1.24-3.25, p = 0.005) than that in those below this height. In computed tomography (CT) scan, the superoinferior diameter of the left atrium (LA) correlated with body height in females, but not in male patients. CONCLUSIONS: Height is associated with AF recurrence after the index CA of PAF in female patients. In Asian populations, women above height 159 cm are twice as likely to have AF recurrence post-ablation as shorter women.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Adulto , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Estatura , Ablação por Cateter/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
13.
Biomedicines ; 11(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36672567

RESUMO

Individuals of Asian descent are at higher risk for developing hyperuricemia and gout as compared to Western populations. Urate-lowering therapy (ULT) is an effective treatment for hyperuricemia and gout. It was reported that febuxostat, one of the ULTs, raises the risk of atrial fibrillation (AF) in elderly populations. Nevertheless, this association has not been properly investigated in Asian populations. We aimed to investigate the development of AF after ULT with different drugs in an Asian population. We conducted a retrospective cohort study using the clinical database at Kaohsiung Veterans General Hospital. Patients newly diagnosed with gout between 1 January 2013 and 31 December 2020 and with a documented baseline serum uric acid (sUA) level but no prior diagnosis of AF were identified. Patients were divided into three groups-allopurinol, benzbromarone, and febuxostat users. During the follow-up period, the risks of incident AF following the initiation of ULT with different drugs were assessed. Development of incident AF was noted in 43 (6%) of the 713 eligible patients during the follow-up period (mean, 49.4 ± 26.6 months). Febuxostat-treated patients had a higher prevalence of certain comorbidities (diabetes mellitus, heart failure, and chronic kidney disease) and higher CHA2DS2-VASc scores. Compared with allopurinol, neither febuxostat nor benzbromarone was associated with increased adjusted hazard ratios (HR) for incident AF (HR: 1.20, 95% confidence interval [CI]: 0.43-3.34; HR: 0.68, 95% CI: 0.22-2.08). There was no difference in the risk of incident AF among Asian patients with gout who received febuxostat, allopurinol, or benzbromarone. Further studies are needed to evaluate long-term cardiovascular outcomes in patients receiving different ULT drugs.

14.
Diagnostics (Basel) ; 11(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34943463

RESUMO

Vascular impairment is a crucial factor associated with chronic muscle pain, but relevant research from the microcirculatory aspect is lacking. Here, we investigated the differences in neck muscle microcirculation detected through laser-doppler flowmetry (LDF) and cervical biomechanics by a videofluoroscopic image in asymptomatic participants and patients with postural neck and shoulder pain. To understand the mechanism behind the effect of myofascial treatment, transverse friction massage (TFM) was applied and the immediate effects of muscular intervention on microcirculation were monitored. In total, 16 asymptomatic participants and 22 patients (mean age = 26.3 ± 2.4 and 25.4 ± 3.2 years, respectively) were recruited. Their neck muscle microcirculation and spinal image sequence were assessed. The differences in the baseline blood flow between the asymptomatic and patient groups were nonsignificant. However, the standard deviations in the measurements of the upper trapezius muscle in the patients were significantly larger (p < 0.05). Regarding the TFM-induced responses of skin microcirculation, the blood flow ratio was significantly higher in the patients than in the asymptomatic participants (p < 0.05). In conclusion, postintervention hyperemia determined through noninvasive LDF may be an indicator for the understanding of the mechanism underlying massage therapies and the design of interventions for postural pain.

15.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34548400

RESUMO

The Plasmodium falciparum proteasome is a potential antimalarial drug target. We have identified a series of amino-amide boronates that are potent and specific inhibitors of the P. falciparum 20S proteasome (Pf20S) ß5 active site and that exhibit fast-acting antimalarial activity. They selectively inhibit the growth of P. falciparum compared with a human cell line and exhibit high potency against field isolates of P. falciparum and Plasmodium vivax They have a low propensity for development of resistance and possess liver stage and transmission-blocking activity. Exemplar compounds, MPI-5 and MPI-13, show potent activity against P. falciparum infections in a SCID mouse model with an oral dosing regimen that is well tolerated. We show that MPI-5 binds more strongly to Pf20S than to human constitutive 20S (Hs20Sc). Comparison of the cryo-electron microscopy (EM) structures of Pf20S and Hs20Sc in complex with MPI-5 and Pf20S in complex with the clinically used anti-cancer agent, bortezomib, reveal differences in binding modes that help to explain the selectivity. Together, this work provides insights into the 20S proteasome in P. falciparum, underpinning the design of potent and selective antimalarial proteasome inhibitors.


Assuntos
Compostos de Boro/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/farmacologia , Administração Oral , Animais , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Domínio Catalítico , Humanos , Malária Falciparum/enzimologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Plasmodium falciparum/enzimologia , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/química
16.
J Med Chem ; 64(10): 6902-6923, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34000802

RESUMO

Stimulator of Interferon Genes (STING) plays an important role in innate immunity by inducing type I interferon production upon infection with intracellular pathogens. STING activation can promote increased T-cell activation and inflammation in the tumor microenvironment, resulting in antitumor immunity. Natural and synthetic cyclic dinucleotides (CDNs) are known to activate STING, and several synthetic CDN molecules are being investigated in the clinic using an intratumoral administration route. Here, we describe the identification of STING agonist 15a, a cyclic dinucleotide structurally diversified from natural ligands with optimized properties for systemic intravenous (iv) administration. Our studies have shown that STING activation by 15a leads to an acute innate immune response as measured by cytokine secretion and adaptive immune response via activation of CD8+ cytotoxic T-cells, which ultimately provides robust antitumor efficacy.


Assuntos
Proteínas de Membrana/agonistas , Nucleotídeos Cíclicos/química , Pirimidinas/química , Administração Intravenosa , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Meia-Vida , Humanos , Imunoterapia , Proteínas de Membrana/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Neoplasias/patologia , Neoplasias/terapia , Nucleotídeos Cíclicos/metabolismo , Nucleotídeos Cíclicos/uso terapêutico , Fosfatos/química , Ratos , Relação Estrutura-Atividade , Transplante Heterólogo
17.
Biochem Biophys Res Commun ; 550: 70-76, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33689882

RESUMO

T cells secrete several inflammatory cytokines that play a critical role in the progression of atherosclerosis. Although green tea epigallocatechin-3-gallate (EGCG) exerts anti-inflammatory and anti-atherosclerotic effects in animals, few studies have identified the mechanism underlying these effects in human primary T cells. This study investigated the pathway involved in EGCG modulation of cytokine secretion in activated human primary T cells. We pre-treated human primary T cells with EGCG (0.1, 1, 5, 10, and 20 µM) for 4 h and incubated them with or without phorbol 12-myristate 13-acetate and ionomycin (P/I) for 20 h. The cytokine production, activator protein (AP)-1 binding activity, and level of mitogen-activated protein kinase (MAPK) were assessed using enzyme-linked immunosorbent assay, electrophoretic mobility shift assay, and Western blotting, respectively. At 10 and 20 µM, EGCG decreased interleukin (IL)-2 levels by 26.0% and 38.8%, IL-4 levels by 41.5% and 55.9%, INF-γ levels by 31.3% and 34.7%, and tumor-necrosis factor (TNF)-α levels by 23.0% and 37.6%, respectively. In addition, the level of phosphorylated c-Jun N-terminal (p-JNK) and extracellular signal-regulated kinase (p-ERK) was decreased, but not the level of p-p38 MAPK. EGCG did not alter any of the total protein amounts, suggesting a selective effect on specific types of MAPKs in stimulated human T cells. EGCG tended to inactivate AP-1 DNA-binding activity. The P/I-induced production of IL-2, IL-4, INF-γ, and TNF-α by human T cells was suppressed by AP-1 inhibitor in a concentration-dependent manner. In conclusion, EGCG suppressed cytokine secretion in activated human primary T cells, and this effect was likely mediated by AP-1 inactivation through the ERK and JNK, but not p38 MAPK, pathways. These results may be related to the mechanisms through which EGCG inhibits immune- or inflammation-related atherogenesis.


Assuntos
Catequina/análogos & derivados , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/farmacologia , Catequina/imunologia , Catequina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Ativação Linfocitária/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Linfócitos T/citologia , Linfócitos T/metabolismo , Fator de Transcrição AP-1/metabolismo
18.
Bioorg Med Chem ; 28(19): 115681, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32912429

RESUMO

Autophagy is postulated to be required by cancer cells to survive periods of metabolic and/or hypoxic stress. ATG7 is the E1 enzyme that is required for activation of Ubl conjugation pathways involved in autophagosome formation. This article describes the design and optimization of pyrazolopyrimidine sulfamate compounds as potent and selective inhibitors of ATG7. Cellular levels of the autophagy markers, LC3B and NBR1, are regulated following treatment with these compounds.


Assuntos
Proteína 7 Relacionada à Autofagia/antagonistas & inibidores , Descoberta de Drogas , Pirazóis/farmacologia , Pirimidinas/farmacologia , Ácidos Sulfônicos/farmacologia , Autofagia/efeitos dos fármacos , Proteína 7 Relacionada à Autofagia/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Ácidos Sulfônicos/síntese química , Ácidos Sulfônicos/química
19.
BMC Cancer ; 19(1): 1083, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711427

RESUMO

BACKGROUND: Hepatoma-derived growth factor (HDGF) participates in angiogenesis and represents a negative prognostic factor in oral cancer. The current study was designed to elucidate the regulatory mechanism between HDGF and vascular endothelial growth factor (VEGF) and the clinical impact of oral cancer. METHODS: TCGA data and surgical samples from oral cancer patients were used for the clinicopathological parameter and survival analysis. Human oral cancer SCC4 and SAS cells were treated with recombinant HDGF protein. VEGF gene expression and protein level were analyzed by RT-PCR, Western blotting, and enzyme-linked immunosorbent assay. The signaling pathways for regulating VEGF expression were investigated. The nucleolin neutralizing antibody and HIF-1α inhibitor were applied to SCC4 cells to investigate their effects on the HDGF-stimulated VEGF pathways. RESULTS: TCGA and immunohistochemical analysis revealed a positive correlation between HDGF and VEGF expression in oral cancer tissues. Recombinant HDGF significantly increased VEGF gene and protein expression in oral cancer SCC4 cells in a dose-dependent manner. HDGF enhanced the phosphorylation levels of AKT and IkB and the protein level of HIF-1α and NF-κB. The nucleolin-neutralizing antibody abolished HDGF-stimulated HIF-1α, NF-κB and VEGF protein expression in SCC4 cells. The HIF-1α inhibitor antagonized the HDGF-induced VEGF gene expression. High VEGF expression was strongly correlated with HDGF expression, advanced disease, and poor survival. CONCLUSION: This study postulated a new pathway in which HDGF activated HIF-1α and then induced VEGF expression through binding to membrane nucleolin under normoxic conditions, leading to poor disease control. The HDGF/HIF-1α/VEGF axis is important for developing future therapeutic strategies.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Masculino , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Prognóstico , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fator A de Crescimento do Endotélio Vascular/genética
20.
Oncogene ; 38(37): 6461-6477, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31332288

RESUMO

Helicobacter pylori (Hp) infection and overexpression of hepatoma-derived growth factor (HDGF) are involved in gastric carcinogenesis. However, the relationship between Hp-induced gastric diseases and HDGF upregulation is not yet completely clear. This study aimed to elucidate the role of HDGF in Hp-induced gastric inflammation and carcinogenesis. HDGF expression in gastric biopsy and serum from patients was analyzed by immunohistochemical and ELISA analysis, respectively. Hp and gastric cells coculture system was employed to delineate the mechanism underlying HDGF overexpression during Hp infection. The gastric pathologies of wild type and HDGF knockout mice after Hp infection were investigated by immunohistochemical, immunoblot, and immunofluorescence analyses. HDGF level was significantly elevated in patients with Hp infection or intestinal metaplasia (IM, a precancerous lesion), and HDGF overexpression was positively correlated with Hp load, IM, and neutrophil infiltration in gastric biopsy. Consistently, patients with Hp infection or IM had significantly higher serum HDGF level. By using coculture assay, Hp infection led to HDGF upregulation and secretion in gastric cells. In mice model, HDGF ablation significantly suppressed the Hp-induced neutrophil infiltration and inflammatory TNF-α/COX-2 signaling, thereby relieving the tissue damage in stomach. This was further supported by that recombinant HDGF (rHDGF) stimulated the differentiation/chemotaxis of cultured neutrophils and oncogenic behaviors of gastric cells. Time series studies showed that Hp infection elicited an inflammatory TNF-α/HDGF/COX-2 cascade in stomach. HDGF secretion by Hp infection promotes the neutrophils infiltration and relays Hp-induced inflammatory signaling. Thus, HDGF may constitute a novel diagnostic marker and therapeutic target for Hp-induced gastritis and carcinogenesis.


Assuntos
Gastrite , Infecções por Helicobacter/complicações , Helicobacter pylori/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Infiltração de Neutrófilos , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiologia , Animais , Carcinogênese/genética , Carcinogênese/imunologia , Carcinogênese/patologia , Células Cultivadas , Mucosa Gástrica/imunologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Gastrite/genética , Gastrite/imunologia , Gastrite/microbiologia , Gastrite/patologia , Células HL-60 , Infecções por Helicobacter/genética , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/genética , Neutrófilos/imunologia , Neutrófilos/metabolismo , Estômago/imunologia , Estômago/microbiologia , Estômago/patologia , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia
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