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1.
Front Oncol ; 14: 1354543, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606099

RESUMO

Nectin-4 is a Ca2+-independent immunoglobulin-like protein that exhibits significantly elevated expression in malignant tumors while maintaining extremely low levels in healthy adult tissues. In recent years, overexpression of Nectin-4 has been implicated in tumor occurrence and development of various cancers, including breast cancer, urothelial cancer, and lung cancer. In 2019, the Food and Drug Administration approved enfortumab vedotin, the first antibody-drug conjugate targeting Nectin-4, for the treatment of urothelial carcinoma. This has emphasized the value of Nectin-4 in tumor targeted therapy and promoted the implementation of more clinical trials of enfortumab vedotin. In addition, many new drugs targeting Nectin-4 for the treatment of malignant tumors have entered clinical trials, with the aim of exploring potential new indications. However, the exact mechanisms by which Nectin-4 affects tumorigenesis and progression are still unclear, and the emergence of drug resistance and treatment-related adverse reactions poses challenges. This article reviews the diagnostic potential, prognostic significance, and molecular role of Nectin-4 in tumors, with a focus on clinical trials in the field of Nectin-4-related tumor treatment and the development of new drugs targeting Nectin-4.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38563882

RESUMO

PURPOSE: Positron emission tomography (PET) with prostate-specific membrane antigen (PSMA) targeting tracers has emerged as a valuable diagnostic tool for prostate cancer (PCa), androgen deprivation therapy (ADT) stands as the cornerstone treatment for advanced PCa, yet forecasting the response to hormonal therapy poses a significant clinical hurdle. METHODS: In a prospective cohort of 86 PCa patients undergoing short-term ADT, this study evaluated the prognostic potential of [18F]DCFPyL PET/CT scans. Comprehensive data encompassing clinical profiles, baseline prostate-specific antigen (PSA) levels, and imaging metrics were assessed. We developed predictive models for assessing decreases in PSA levels (PSA50 and PSA70) based on a combination of PET-related parameters and clinical factors. Kaplan-Meier survival analysis was utilized to ascertain the prognostic value of PET-based metrics. RESULTS: In this study, elevated [18F]DCFPyL uptake within the primary tumor, as indicated by a SUV ≥ 6.78 (p = 0.0024), and a reduction in the tumor volume (TV) of primary PSMA-avid tumor with PSMA-TV < 41.96 cm3 (p = 0.038), as well as an increased burden of metastatic PSMA-avid tumor, with PSMA-TV (PSMA-TV ≥ 71.39 cm3) (p = 0.012) were identified in association with diminished progression-free survival (PFS). PET and clinical parameters demonstrated constrained predictive capacity for PSA50 response as indicated by an area under the curve (AUC) of 0.442. CONCLUSION: Our study revealed that pretreatment [18F]DCFPyL uptake in primary or metastatic tumor sites is prognostically relevant in high-risk PCa patients undergoing ADT. Further research is needed to develop robust predictive models in this multifaceted landscape of PCa management.

3.
Int Immunopharmacol ; 130: 111811, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38457929

RESUMO

Glaucoma is characterized by a progressive loss of retinal ganglion cells (RGCs), leading to irreversible visual function impairment. Sustained increase in intraocular pressure represents a major risk factor for glaucoma, yet the underlying mechanisms of RGC apoptosis induced by intraocular pressure remains unclear. This study aims to investigate the role of TRPV4 in RGC apoptosis in a rat model of chronic ocular hypertension (COH) and the underlying molecular mechanism. In the COH rat models, we evaluated the visual function, retinal pathological changes and RGC apoptosis. TRPV4 expression and downstream signaling molecules were also detected. We found that RGC density decreased and RGC apoptosis was induced in COH eyes compared with control eyes. TRPV4 expression increased significantly in response to elevated IOP. TRPV4 inhibition by the TRPV4 antagonist HC-067047 (HC-067) suppressed RGC apoptosis and protected visual function. HC-067 treatment upregulated the phosphorylation of CaMKII in both control and COH eyes. Finally, HC-067 treatment suppressed the production of TNF-α induced by ocular hypertension. The TRPV4 antagonist HC-067 might suppress RGC apoptosis by regulating the activation of CaMKII and inhibiting the production of TNF-α in the COH model. This indicated that TRPV4 antagonists may be a potential and novel therapeutic strategy for glaucoma.


Assuntos
Apoptose , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Morfolinas , Hipertensão Ocular , Pirróis , Células Ganglionares da Retina , Canais de Cátion TRPV , Fator de Necrose Tumoral alfa , Animais , Ratos , Apoptose/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Modelos Animais de Doenças , Glaucoma/tratamento farmacológico , Hipertensão Ocular/tratamento farmacológico , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/patologia , Canais de Cátion TRPV/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Pirróis/farmacologia , Pirróis/uso terapêutico
4.
Materials (Basel) ; 16(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38005000

RESUMO

A Ni60+30%WC composite coating was prepared on the surface of Q235 steel by utilizing a high cooling rate, small thermal deformation of the substrate material, and the good metallurgical bonding characteristics of laser cladding technology. This paper focuses on the study of the composite coatings prepared under different process parameters in order to select the optimal process parameters and provide theoretical guidance for future practical applications. The macroscopic morphology and microstructure of t he composite coatings were investigated with the help of an optical microscope (OM) and a scanning electron microscope (SEM). The elemental distribution of the composite coatings was examined using an X-ray diffractometer. The microhardness and wear resistance of the composite coatings were tested using a microhardness tester, a friction tester, and a three-dimensional (3D) profilometer. The results of all the samples showed that the Ni60+30%WC composite coatings prepared at a laser power of 1600 W and a scanning speed of 10 mm/s were well formed, with a dense microstructure, and the microhardness is more than four times higher than the base material, the wear amount is less than 50% of the base material, and the wear resistance has been significantly improved. Therefore, the experimental results for the laser power of 1600 W and scanning speed of 10 mm/s are the optimal process parameters for the preparation of Ni60+30%WC.

5.
Eur J Clin Pharmacol ; 79(12): 1665-1673, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37796282

RESUMO

PURPOSE: To analyze the characteristics of overlapping meta-analyses based on randomized controlled trials (RCTs) which reported PD-1/PD-L1 inhibitors in non-small cell cancer (NSCLC). METHODS: Meta-analyses were identified from English and Chinese databases until January 1, 2022. Differences in characteristics of overlapping meta-analyses that conducted in China and other countries were compared to assess their publication propensity. The corrected covered area (CCA) and coverage of relevant RCTs were analyzed for subtopics according to detailed intervention types. The waste and redundancy of evidence were assessed in the case of PD-1/PD-L1 inhibitor monotherapy for second-line treatment for NSCLC. RESULTS: Fifty-nine meta-analyses published in English and 17 meta-analyses published in Chinese reporting 26 RCTs were identified. Fifty-three (69.74%) meta-analyses were conducted in China. The overlapping meta-analyses in China were more likely to be from hospitals, supported by government funding, integrate first and second-line therapies. Five of the six subtopics had overlapping meta-analyses according to specific types of interventions. The CCA of overlapping meta-analyses ranged from 33.33 to 63.19%, and the coverage of relevant RCTs ranged from 63.64 to 100%. All the conclusions of overlapping meta-analyses have been consistent in the subtopic of PD-1/PD-L1 inhibitor monotherapy for second-line treatment since 2017. CONCLUSION: Overlapping meta-analyses of PD-1/PD-L1 inhibitors in NSCLC hints that meta-analyses under this topic probably exist serious redundancy. Future research should focus on prospective registration of protocols for systematic reviews/meta-analyses, scientific designed PICO, and cumulative meta-analysis to reduce redundant and wasted studies. Journals should strengthen the requirement for reviewing previously published evidence in manuscript review.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Receptor de Morte Celular Programada 1 , Revisões Sistemáticas como Assunto
6.
Nat Metab ; 5(7): 1159-1173, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37337119

RESUMO

Increased expression of branched-chain amino acid transaminase 1 or 2 (BCAT1 and BCAT2) has been associated with aggressive phenotypes of different cancers. Here we identify a gain of function of BCAT1 glutamic acid to alanine mutation at codon 61 (BCAT1E61A) enriched around 2.8% in clinical gastric cancer samples. We found that BCAT1E61A confers higher enzymatic activity to boost branched-chain amino acid (BCAA) catabolism, accelerate cell growth and motility and contribute to tumor development. BCAT1 directly interacts with RhoC, leading to elevation of RhoC activity. Notably, the BCAA-derived metabolite, branched-chain α-keto acid directly binds to the small GTPase protein RhoC and promotes its activity. BCAT1 knockout-suppressed cell motility could be rescued by expressing BCAT1E61A or adding branched-chain α-keto acid. We also identified that candesartan acts as an inhibitor of BCAT1E61A, thus repressing RhoC activity and cancer cell motility in vitro and preventing peritoneal metastasis in vivo. Our study reveals a link between BCAA metabolism and cell motility and proliferation through regulating RhoC activation, with potential therapeutic implications for cancers.


Assuntos
Neoplasias , Humanos , Proteínas , Proliferação de Células , Cetoácidos/metabolismo , Aminoácidos de Cadeia Ramificada/metabolismo , Transaminases/metabolismo
7.
Heliyon ; 9(5): e16097, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215840

RESUMO

Coronary arterial disease (CAD) is the leading cause of mortality in the world. Hyperuricemia has recently emerged as a novel independent risk factor of CAD, in addition to the traditional risk factors such as hyperlipidemia, smoking, and obesity. Several clinical studies have shown that hyperuricemia is strongly associated with the risk, progression and poor prognosis of CAD, as well as verifying an association with traditional CAD risk factors. Uric acid or enzymes in the uric acid production pathway are associated with inflammation, oxidative stress, regulation of multiple signaling pathways and the renin-angiotensin-aldosterone system (RAAS), and these pathophysiological alterations are currently the main mechanisms of coronary atherosclerosis formation. The risk of death from CAD can be effectively reduced by the uric acid-lowering therapy, but the interventional treatment of uric acid levels in patients with CAD remains controversial due to the diversity of co-morbidities and the complexity of causative factors. In this review, we analyze the association between hyperuricemia and CAD, elucidate the possible mechanisms by which uric acid induces or exacerbates CAD, and discuss the benefits and drawbacks of uric acid-lowering therapy. This review could provide theoretical references for the prevention and management of hyperuricemia-associated CAD.

9.
Natl Sci Rev ; 9(5): nwab212, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35663242

RESUMO

BCAT2-mediated branched-chain amino acid (BCAA) catabolism is critical for pancreatic ductal adenocarcinoma (PDAC) development, especially at an early stage. However, whether a high-BCAA diet promotes PDAC development in vivo, and the underlying mechanism of BCAT2 upregulation, remain undefined. Here, we find that a high-BCAA diet promotes pancreatic intraepithelial neoplasia (PanIN) progression in LSL-KrasG12D/+ ; Pdx1-Cre (KC) mice. Moreover, we screened with an available deubiquitylase library which contains 31 members of USP family and identified that USP1 deubiquitylates BCAT2 at the K229 site. Furthermore, BCAA increases USP1 protein at the translational level via the GCN2-eIF2α pathway both in vitro and in vivo. More importantly, USP1 inhibition recedes cell proliferation and clone formation in PDAC cells and attenuates pancreas tumor growth in an orthotopic transplanted mice model. Consistently, a positive correlation between USP1 and BCAT2 is found in KC; LSL-KrasG12D/+ ; p53flox/+ ; Pdx1-Cre mice and clinical samples. Thus, a therapeutic targeting USP1-BCAT2-BCAA metabolic axis could be considered as a rational strategy for treatment of PDAC and precisive dietary intervention of BCAA has potentially translational significance.

10.
Signal Transduct Target Ther ; 7(1): 192, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35729157

RESUMO

Folic acid, served as dietary supplement, is closely linked to one-carbon metabolism and methionine metabolism. Previous clinical evidence indicated that folic acid supplementation displays dual effect on cancer development, promoting or suppressing tumor formation and progression. However, the underlying mechanism remains to be uncovered. Here, we report that high-folate diet significantly promotes cancer development in mice with hepatocellular carcinoma (HCC) induced by DEN/high-fat diet (HFD), simultaneously with increased expression of methionine adenosyltransferase 2A (gene name, MAT2A; protein name, MATIIα), the key enzyme in methionine metabolism, and acceleration of methionine cycle in cancer tissues. In contrast, folate-free diet reduces MATIIα expression and impedes HFD-induced HCC development. Notably, methionine metabolism is dynamically reprogrammed with valosin-containing protein p97/p47 complex-interacting protein (VCIP135) which functions as a deubiquitylating enzyme to bind and stabilize MATIIα in response to folic acid signal. Consistently, upregulation of MATIIα expression is positively correlated with increased VCIP135 protein level in human HCC tissues compared to adjacent tissues. Furthermore, liver-specific knockout of Mat2a remarkably abolishes the advocating effect of folic acid on HFD-induced HCC, demonstrating that the effect of high or free folate-diet on HFD-induced HCC relies on Mat2a. Moreover, folate and multiple intermediate metabolites in one-carbon metabolism are significantly decreased in vivo and in vitro upon Mat2a deletion. Together, folate promotes the integration of methionine and one-carbon metabolism, contributing to HCC development via hijacking MATIIα metabolic pathway. This study provides insight into folate-promoted cancer development, strongly recommending the tailor-made folate supplement guideline for both sub-healthy populations and patients with cancer expressing high level of MATIIα expression.


Assuntos
Ácido Fólico , Metionina Adenosiltransferase , Animais , Dieta , Ácido Fólico/farmacologia , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Metionina/metabolismo , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Camundongos
11.
Sci China Life Sci ; 65(10): 2017-2030, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35366151

RESUMO

Epithelial ovarian cancer (EOC) exhibits strong dependency on the tricarboxylic acid (TCA) cycle and oxidative phosphorylation to fuel anabolic process. Here, we show that malate dehydrogenase 2 (MDH2), a key enzyme of the TCA cycle, is palmitoylated at cysteine 138 (C138) residue, resulting in increased activity of MDH2. We next identify that ZDHHC18 acts as a palmitoyltransferase of MDH2. Glutamine deprivation enhances MDH2 palmitoylation by increasing the binding between ZDHHC18 and MDH2. MDH2 silencing represses mitochondrial respiration as well as ovarian cancer cell proliferation both in vitro and in vivo. Intriguingly, re-expression of wild-type MDH2, but not its palmitoylation-deficient C138S mutant, sustains mitochondrial respiration and restores the growth as well as clonogenic capability of ovarian cancer cells. Notably, MDH2 palmitoylation level is elevated in clinical cancer samples from patients with high-grade serous ovarian cancer. These observations suggest that MDH2 palmitoylation catalyzed by ZDHHC18 sustains mitochondrial respiration and promotes the malignancy of ovarian cancer, yielding possibilities of targeting ZDHHC18-mediated MDH2 palmitoylation in the treatment of EOC.


Assuntos
Malato Desidrogenase , Neoplasias Ovarianas , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Cisteína , Feminino , Glutamina , Humanos , Lipoilação , Malato Desidrogenase/química , Malato Desidrogenase/metabolismo , Respiração , Ácidos Tricarboxílicos
12.
J Biomed Nanotechnol ; 17(2): 205-215, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33785092

RESUMO

Imaging-guided cancer theranostic is a promising strategy for cancer diagnostic and therapeutic. Photodynamic therapy (PDT), as an approved treatment modality, is limited by the poor solubility and dispersion of photosensitizers (PS) in biological fluids. Herein, it is demonstrated that superparamagnetic iron oxide (SPIO)-based nanoparticles (SCFs), prepared by conjugated with Chlorin e6 (Ce6) and modified with folic acid (FA) on the surface, can be used as versatile drug delivery vehicles for effective PDT. The nanoparticles are great carriers for photosensitizer Ce6 with an extremely high loading efficiency. In vitro fluorescence imaging and in vivo magnetic resonance imaging (MRI) results indicated that SCFs selectively accumulated in tumor cells. Under near-infrared laser irradiation, SCFs were confirmed to be capable of inducing low cell viability of RM-1 cells In vitro and displaying efficient tumor ablation with negligible side effects in tumor-bearing mice models.


Assuntos
Nanopartículas , Fotoquimioterapia , Porfirinas , Animais , Linhagem Celular Tumoral , Clorofilídeos , Compostos Férricos , Ácido Fólico , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Fármacos Fotossensibilizantes/farmacologia , Medicina de Precisão , Nanomedicina Teranóstica
13.
Chemistry ; 23(42): 10187-10194, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28590063

RESUMO

A noble-metal-free and highly efficient bifunctional catalyst for overall water splitting is greatly desirable to generate clean and sustainable energy carriers such as hydrogen, but enormous challenges remain. Herein, porous interconnected iron-nickel nitride nanosheets are designed and grown on carbon fiber cloth (FeNi-N/CFC); combining a facile electrodeposition method and in situ nitriding process. The as-synthesized FeNi-N/CFC, with a low mass loading of 0.25 mg cm-2 , exhibits excellent catalytic activities for both the oxygen evolution reaction (OER) with 20 mA cm-2 at an overpotential (η) of 232 mV and also the hydrogen evolution reaction (HER) with 10 mA cm-2 at η=106 mV. As a bifunctional electrocatalyst for overall water splitting FeNi-N/CFC only requires a cell voltage of 1.55 V to drive a current density (j) of 10 mA cm-2 and shows robust long-term durability at j>360 mA cm-2 with a negligible change in current density over 60 h; revealing its promising application in commercial electrolyzers.

14.
Scanning ; 38(6): 545-553, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26751133

RESUMO

The aim of this study was to analyze the effects of ultrasound bath intensity, CaCl2 and sodium tripolyphosphate (STPP) concentration on the ultrastructure of longissimus muscle fiber from milk goats. The sarcomere length was measured by atomic force microscopy. According to the results of AFM images, the sarcomere length is longest when the conditions were an intensity of 100 W ultrasound bath (42.77% increment), a concentration of 300 mM CaCl2 injection (44.68% increment) or 90 mM STPP injection (19.41% increment). Apart from the sarcomere length, the study put forward a potential index (roughness) to represent tenderness of meat which was treated by ultrasound bath. Among different methods, ultrasound bath was chosen as the preferred tenderization method. SCANNING 38:545-553, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Cloreto de Cálcio/farmacologia , Microscopia de Força Atômica/métodos , Fibras Musculares Esqueléticas/ultraestrutura , Polifosfatos/farmacologia , Animais , Cabras , Fibras Musculares Esqueléticas/efeitos dos fármacos , Sarcômeros/efeitos dos fármacos , Sarcômeros/ultraestrutura , Ultrassom
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