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1.
J Am Chem Soc ; 146(17): 12206-12214, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38637324

RESUMO

Chiral nanographenes (NGs) have garnered significant interest as optoelectronic materials in recent years. While helically chiral NGs have been extensively studied, axially chiral NGs have only witnessed limited examples, with no prior reports of axially chiral nonbenzenoid NGs. Herein we report an axially chiral nonbenzenoid nanographene featuring six pentagons and four heptagons. This compound, denoted as 2, was efficiently synthesized via an efficient Pd-catalyzed aryl silane homocoupling reaction. The presence of two bulky 3,5-di-tert-butylphenyl groups around the axis connecting the two nonbenzenoid PAH (AHR) segments endows 2 with atropisomeric chirality and high racemization energy barrier, effectively preventing racemization of both R- and S-enantiomers at room temperature. Optically pure R-2 and S-2 were obtained by chiral HPLC separation, and they exhibit circular dichroism (CD) activity at wavelengths up to 660 nm, one of the longest wavelengths with CD responses reported for the chiral NGs. Interestingly, racemic 2 forms a homoconfiguration π-dimer in the crystal lattice, belonging to the I222 chiral space group. Consequently, this unique structure renders crystals of 2 with a second harmonic generation (SHG) response, distinguishing it from all the reported axially chiral benzenoid NGs. Moreover, R-2 and S-2 also exhibit SHG-CD properties.

2.
Molecules ; 28(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37513401

RESUMO

An unprecedented N-alkylation of 3-nitroindoles with para-quinone methides was developed for the first time. Using potassium carbonate as the base, a wide range of structurally diverse N-diarylmethylindole derivatives were obtained with moderated to good yields via the protection group migration/aza-1,6-Michael addition sequences. The reaction process was also demonstrated by control experiments. Different from the previous advances where 3-nitrodoles served as electrophiles trapping by various nucleophiles, the reaction herein is featured that 3-nitrodoles is defined with latent N-centered nucleophiles to react with ortho-hydrophenyl p-QMs for construction of various N-diarylmethylindoles.

3.
Angew Chem Int Ed Engl ; 62(39): e202304632, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37338996

RESUMO

Non-benzenoid polycyclic aromatic hydrocarbons (PAHs) have received a lot of attention because of their unique optical, electronic, and magnetic properties, but their synthesis remains challenging. Herein, we report a non-benzenoid isomer of peri-tetracene, diazulenorubicene (DAR), with two sets of 5/7/5 membered rings synthesized by a (3+2) annulation reaction. Compared with the precursor containing only 5/7 membered rings, the newly formed five membered rings switch the aromaticity of the original heptagon/pentagon from antiaromatic/aromatic to non-aromatic/antiaromatic respectively, modify the intermolecular packing modes, and lower the LUMO levels. Notably, compound 2 b (DAR-TMS) shows p-type semiconducting properties with a hole mobility up to 1.27 cm2  V-1 s-1 . Moreover, further extension to larger non-benzenoid PAHs with 19 rings was achieved through on-surface chemistry from the DAR derivative with one alkynyl group.

4.
Angew Chem Int Ed Engl ; 62(17): e202300990, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-36861376

RESUMO

Non-benzenoid acenes containing heptagons have received increasing attention. We herein report a heptacene analogue containing a quinoidal benzodi[7]annulene core. Derivatives of this new non-benzenoid acene were obtained through an efficient synthetic strategy involving an Aldol condensation and a Diels-Alder reaction as key steps. The configuration of this heptacene analogue can be modulated from a wavy to a curved one by just varying the substituents from a (triisopropylsilyl)ethynyl group to a 2,4,6-triisopropylphenyl (Trip) group. When mesityl (Mes) groups are linked to the heptagons, the resulting non-benzenoid acene displays polymorphism with a tunable configuration from a curved to a wavy one upon varying the crystallization conditions. In addition, this new non-benzenoid acene can be oxidized or reduced by NOSbF6 or KC8 to the respective radical cation or radical anion. Compared with the neutral acene, the radical anion shows a wavy configuration and the central hexagon becomes aromatic.

5.
Adv Sci (Weinh) ; 10(15): e2300530, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36967566

RESUMO

Emissive organic semiconductors are highly demanding for organic light-emitting transistors (OLETs) and electrically pumped organic lasers (EPOLs). However, it remains a great challenge to obtain organic semiconductors with high carrier mobility and high photoluminescence quantum yield simultaneously. Here, a new design strategy is reported for highly emissive ambipolar and even n-type semiconductors by introducing perfluorophenyl groups into polycyclic aromatic hydrocarbons such as perylene and anthracene. The results reveal that 3,9-diperfluorophenyl perylene (5FDPP) exhibits the ambipolar semiconducting property with hole and electron mobilities up to 0.12 and 1.89 cm2 V-1 s-1 , and a photoluminescence quantum yield of 55%. One of the crystal forms of 5FDPA exhibits blue emission with an emission quantum yield of 52% and simultaneously shows the n-type semiconducting property with an electron mobility up to 2.65 cm2 V-1 s-1 , which is the highest value among the reported organic emissive n-type semiconductors. Furthermore, crystals of 5FDPP are utilized to fabricate OLETs by using Ag as source-drain electrodes. The electroluminescence is detected in the transporting channels with an external quantum efficiency (EQE) of up to 2.2%, and the current density is up to 145 kA cm-2 , which are among the highest values for single-component OLETs with symmetric electrodes.

6.
J Cardiothorac Surg ; 18(1): 16, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631901

RESUMO

BACKGROUND: Preoperative anemia is common in patients undergoing cardiac surgery with various etiologies, among which iron deficiency is the leading cause. However, the benefit of intravenous (IV) iron for the treatment of anemia before cardiac surgery is uncertain. This updated meta-analysis aimed to evaluate the efficacy of IV iron in adult cardiac surgery patients with preoperative anemia. METHODS: This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched Embase, PubMed and the Cochrane Central Register of Controlled Trials to identify eligible randomized controlled trials (RCTs) and observational studies. Quality was assessed using the Cochrane Collaboration risk of bias tool and Newcastle-Ottawa scale, and the strength of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria. Trial sequential analysis was performed on the primary outcome (transfusion rate) to confirm whether firm evidence was reached. RESULTS: Six RCTs (936 patients) and 5 observational studies (1350 patients) were included in this meta-analysis. The IV iron group and the control group were comparable in terms of transfusion rate [55.1% vs 60.9%, risk ratio (RR) = 0.91, 95% confidence interval (CI) 0.81-1.03, P = 0.13, low quality]. There were no significant differences in units transfused per patient, ICU stay and hospital length of stay between the two groups. And pooled data showed a benefit of IV iron compared to the control group on mortality (2.76% vs 3.75%, RR = 0.58, 95% CI 0.36-0.95, P = 0.03, moderate quality) and no mortality reduction existed when including only RCTs. CONCLUSIONS: This meta-analysis suggested that IV iron treatment for patients with anemia before cardiac surgery did not reduce the transfusion requirement (low quality), but it was associated with decreased mortality (moderate quality). More large-scale, high-quality randomized clinical trials are warranted to confirm or refute our findings. PROSPERO registry reference: CRD42022331875.


Assuntos
Anemia , Procedimentos Cirúrgicos Cardíacos , Adulto , Humanos , Ferro/uso terapêutico , Anemia/tratamento farmacológico , Transfusão de Sangue , Administração Intravenosa , Estudos Observacionais como Assunto
7.
Angew Chem Int Ed Engl ; 61(36): e202208378, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35811386

RESUMO

We herein report a phosphoric-acid-substituted tetraphenylethene (T-P) capable of adapting its geometric configuration and biological activity to the microenvironment upon light irradiation for apoptosis modulation. Different from most ultraviolet-responsive isomerization, T-P undergoes cis-trans isomerization under visible light irradiation, which is biocompatible and thus photo-modulation is possible in living biosystems. By using alkaline phosphatase (ALP) and albumin as dual targets, T-P isomers display different protein binding selectivity, cancer-cell internalization efficiency and apoptosis-inducing ability. The proapoptotic activity was found to be kinetically controlled by the enzymatic reaction with ALP and regulated by co-existing albumin. Motivated by these findings, two-way modulation of proapoptotic effect and on-demand boosting anticancer efficacy were realized in vitro and in vivo using light and endogenous proteins as multiple non-invasive switching stimuli.


Assuntos
Neoplasias , Albuminas , Humanos , Isomerismo , Luz , Proteínas , Microambiente Tumoral
8.
Chem Commun (Camb) ; 58(33): 5100-5103, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35388834

RESUMO

A perylene five-membered ring diimide, PDI39, was developed as a new electron-deficient building block for n-type semiconductors. The π-expanded conjugated molecules containing azulenes were synthesized from PDI39. These conjugated molecules show helical geometry and near-infrared absorption up to 810 nm.

9.
Scand J Gastroenterol ; 57(8): 990-995, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35275756

RESUMO

BACKGROUND: Acute pancreatitis is an acute inflammatory disorder of the pancreas, and severe acute pancreatitis is associated with high mortality. Early assessment the severity of AP has an important significance for improving clinical outcomes. Our object aimed to develop a nomogram with high simplicity and rapidity for predicting the severity of acute pancreatitis. METHODS: Patients admitted to the Hunan Provincial People's Hospital within 72 h from onset of AP from January 2010 and December 2020 were enrolled to establish a nomogram. Independent predictors were determined using univariate and multivariate analysis and then assembled to construct a predicting nomogram. The performance of proposed nomogram was evaluated by Brier score and Harrell's concordance index (C-index). Meanwhile, clinical data of AP patients from January 2021 to January 2022 were collected for external validation. RESULTS: Album (OR 0.891, 95%CI 0.867-0.917), calcium (OR 0.151, 95%CI 0.084-0.273), neutrophil to lymphocyte ratio (OR 1.055, 95%CI 1.023-1.088) and systemic inflammatory response syndrome (OR 6.292, 95%CI 4.459-8.879) were identified as independent factors of SAP after univariate and multivariate analysis (p < .05). A predictive nomogram was accordingly established using these four independent variables. The internally verified C-index was 0.796 (95% CI 0.773-0.818), Brier score was 0.138. The externally verified C index was 0.820 (95% CI 0.754-0.887). CONCLUSION: A nomogram for predicting the severity of AP was well developed, it may be of great significance for clinicians to quickly assess the progress of AP and choose more-targeted strategies.


Assuntos
Pancreatite , Doença Aguda , Humanos , Nomogramas , Pancreatite/diagnóstico , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença
10.
Acta Pharmacol Sin ; 43(6): 1594-1604, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34588618

RESUMO

Physapubenolide (PB), a withanolide-type compound extracted from the traditional herb Physalis minima L., has been demonstrated to exert remarkable cytotoxicity against cancer cells; however, its molecular mechanisms are still unclear. In this study, we demonstrated that PB inhibited cell proliferation and migration in melanoma cells by inducing cell apoptosis. The anticancer activity of PB was further verified in a melanoma xenograft model. To explore the mechanism underlying the anticancer effects of PB, we carried out an in silico target prediction study, which combined three approaches (chemical similarity searching, quantitative structure-activity relationship (QSAR), and molecular docking) to identify the targets of PB, and found that PB likely targets 3-hydroxy-methylglutaryl CoA reductase (HMGCR), the rate-limiting enzyme of the mevalonate pathway, which promotes cancer cell proliferation, migration, and metastasis. We further demonstrated that PB interacted with HMGCR, decreased its protein expression and inhibited the HMGCR/YAP pathway in melanoma cells. In addition, we found that PB could restore vemurafenib sensitivity in vemurafenib-resistant A-375 cells, which was correlated with the downregulation of HMGCR. In conclusion, we demonstrate that PB elicits anticancer action and enhances sensitivity to vemurafenib by targeting HMGCR.


Assuntos
Melanoma , Vitanolídeos , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Melanoma/tratamento farmacológico , Simulação de Acoplamento Molecular , Vemurafenib , Vitanolídeos/farmacologia
11.
Front Med (Lausanne) ; 9: 1021899, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687401

RESUMO

Background: Portal vein thrombosis (PVT) is an increasingly recognized complication of cirrhosis and possibly associated with mortality. This study aims to evaluate provoking factors for PVT, then establish a concise and efficient nomogram for predicting PVT presence among admitted cirrhotic patients. Materials and methods: All cirrhotic patients admitted in Hunan Provincial People's Hospital between January 2010 and September 2020 were retrospectively reviewed, the clinical and laboratory data were collected. Multivariate logistic regression analysis and the least absolute shrinkage and selection operator regression method were used for screening the independent predictors and constructing the nomogram. The calibration curve was plotted to evaluate the consistent degree between observed outcomes and predicted probabilities. The area under the receiver operating characteristics curve was used to assess the discriminant performance. The decision curve analysis (DCA) was carried out to evaluate the benefits of nomogram. Results: A total of 4,479 patients with cirrhosis were enrolled and 281 patients were identified with PVT. Smoking history, splenomegaly, esophagogastric varices, surgical history, red blood cell transfusion, and D-dimer were independent risk factors for PVT in cirrhosis. A nomogram was established with a good discrimination capacity and predictive efficiency with an the area under the curve (AUC) of 0.704 (95% CI: 0.664-0.745) in the training set and 0.685 (95% CI: 0.615-0.754) in the validation set. DCA suggested the net benefit of nomogram had a superior risk threshold probability. Conclusion: A concise and efficient nomogram was established with good performance, which may aid clinical decision making and guide best treatment measures.

12.
Ecotoxicol Environ Saf ; 222: 112525, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274838

RESUMO

The information of the acute oral toxicity for most polycyclic aromatic hydrocarbons (PAHs) in mammals are lacking due to limited experimental resources, leading to a need to develop reliable in silico methods to evaluate the toxicity endpoint. In this study, we developed the quantitative structure-activity relationship (QSAR) models by genetic algorithm (GA) and multiple linear regression (MLR) for the rat acute oral toxicity (LD50) of PAHs following the strict validation principles of QSAR modeling recommended by OECD. The best QSAR model comprised eight simple 2D descriptors with definite physicochemical meaning, which showed that maximum atom-type electrotopological state, van der Waals surface area, mean atomic van der Waals volume, and total number of bonds are main influencing factors for the toxicity endpoint. A true external set (554 compounds) without rat acute oral toxicity values, and 22 limit test compounds, were firstly predicted along with reliability assessment. We also compared our proposed model with the OPERA predictions and recently published literature to prove the prediction reliability. Furthermore, the interspecies toxicity (iST) models of PAHs between rat and mouse were also established, validated and employed for filling data gap. Overall, our developed models should be applicable to new or untested or not yet synthesized PAHs falling within the applicability domain (AD) of the models for rapid acute oral toxicity prediction, thus being important for environmental or personal exposure risk assessment under regulatory frameworks.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Relação Quantitativa Estrutura-Atividade , Animais , Dose Letal Mediana , Modelos Lineares , Camundongos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Ratos , Reprodutibilidade dos Testes
13.
Acta Pharmacol Sin ; 42(7): 1180-1189, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33149145

RESUMO

Anexelekto (AXL), a member of the TYRO3-AXL-MER (TAM) family of receptor tyrosine kinases (RTK), is overexpressed in varieties of tumor tissues and promotes tumor development by regulating cell proliferation, migration and invasion. In this study, we investigated the role of AXL in regulating glycolysis in human ovarian cancer (OvCa) cells. We showed that the expression of AXL mRNA and protein was significantly higher in OvCa tissue than that in normal ovarian epithelial tissue. In human OvCa cell lines suppression of AXL significantly inhibited cell proliferation, and increased the sensitivity of OvCa cells to cisplatin, which also proved by nude mice tumor formation experiment. KEGG analysis showed that AXL was significantly enriched in the glycolysis pathways of cancer. Changes in AXL expression in OvCa cells affect tumor glycolysis. We demonstrated that the promotion effect of AXL on glycolysis was mediated by phosphorylating the M2 isoform of pyruvate kinase (PKM2) at Y105. AXL expression was significantly higher in cisplatin-resistant OvCa cells A2780/DDP compared with the parental A2780 cells. Inhibition of AXL decreased the level of glycolysis in A2780/DDP cells, and increased the cytotoxicity of cisplatin against A2780/DDP cells, suggesting that AXL-mediated glycolysis was associated with cisplatin resistance in OvCa. In conclusion, this study demonstrates for the first time that AXL is involved in the regulation of the Warburg effect. Our results not only highlight the clinical value of targeting AXL, but also provide theoretical basis for the combination of AXL inhibitor and cisplatin in the treatment of OvCa.


Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Glicólise/fisiologia , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Antineoplásicos/farmacologia , Benzocicloeptenos/farmacologia , Benzocicloeptenos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Desoxiglucose/farmacologia , Desoxiglucose/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Glicólise/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos Nus , Neoplasias Ovarianas/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Triazóis/farmacologia , Triazóis/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase Axl
14.
Front Pharmacol ; 11: 550469, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013387

RESUMO

The M2 isoform of pyruvate kinase (PKM2), as a key glycolytic enzyme, plays important roles in tumorigenesis and chemotherapeutic drug resistance. However, the intricate mechanism of PKM2 as a protein kinase regulating breast cancer progression and tamoxifen resistance needs to be further clarified. Here, we reported that PKM2 controls the expression of survivin by phosphorylating c-Myc at Ser-62. Functionally, PKM2 knockdown suppressed breast cancer cell proliferation and migration, which could be rescued by overexpression of survivin. Interestingly, we found that the level of PKM2 expression was upregulated in the tamoxifen resistant breast cancer cells MCF-7/TAMR, and knockdown of PKM2 sensitized the cells to 4-hydroxytamoxifen (4OH-T). In addition, the elevated level of PKM2 correlates with poor relapse-free survival in breast cancer patients treated with tamoxifen. Overall, our findings demonstrated that PKM2-c-Myc-survivin cascade regulated the proliferation, migration and tamoxifen resistance of breast cancer cells, suggesting that PKM2 represents a novel prognostic marker and an attractive target for breast cancer therapeutics, and that PKM2 inhibitor combined with tamoxifen may be a promising strategy to reverse tamoxifen resistance in breast cancer patients.

15.
Oncogene ; 39(43): 6704-6718, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32958832

RESUMO

Autophagy can protect stressed cancer cell by degradation of damaged proteins and organelles. However, the regulatory mechanisms behind this cellular process remain incompletely understood. Here, we demonstrate that RSK2 (p90 ribosomal S6 kinase 2) plays a critical role in ER stress-induced autophagy in breast cancer cells. We demonstrated that the promotive effect of RSK2 on autophagy resulted from directly binding of AMPKα2 in nucleus and phosphorylating it at Thr172 residue. IRE1α, an ER membrane-associated protein mediating unfolded protein response (UPR), is required for transducing the signal for activation of ERK1/2-RSK2 under ER stress. Suppression of autophagy by knockdown of RSK2 enhanced the sensitivity of breast cancer cells to ER stress both in vitro and in vivo. Furthermore, we demonstrated that inhibition of RSK2-mediated autophagy rendered breast cancer cells more sensitive to paclitaxel, a chemotherapeutic agent that induces ER stress-mediated cell death. This study identifies RSK2 as a novel controller of autophagy in tumor cells and suggests that targeting RSK2 can be exploited as an approach to reinforce the efficacy of ER stress-inducing agents against cancer.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos/farmacologia , Autofagia , Neoplasias da Mama/patologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Núcleo Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endorribonucleases/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7 , Camundongos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Eur J Med Chem ; 199: 112421, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32428794

RESUMO

It has been realized that FDA approved drugs may have more molecular targets than is commonly thought. Thus, to find the exact drug-target interactions (DTIs) is of great significance for exploring the new molecular mechanism of drugs. Here, we developed a multi-scale system pharmacology (MSSP) method for the large-scale prediction of DTIs. We used MSSP to integrate drug-related and target-related data from multiple levels, the network structural data formed by known drug-target relationships for predicting likely unknown DTIs. Prediction results revealed that Ixabepilone, an epothilone B analog for treating breast cancer patients, may target Bcl-2, an oncogene that contributes to tumor progression and therapy resistance by inhibiting apoptosis. Furthermore, we demonstrated that Ixabepilone could bind with Bcl-2 and decrease its protein expression in breast cancer cells. The down-regulation of Bcl-2 by Ixabepilone is resulted from promoting its degradation by affecting p-Bcl-2. We further found that Ixabepilone could induce autophagy by releasing Beclin1 from Beclin1/Bcl-2 complex. Inhibition of autophagy by knockdown of Beclin1 or pharmacological inhibitor augmented apoptosis, thus enhancing the antitumor efficacy of Ixabepilone against breast cancer cells in vitro and in vivo. In addition, Ixabepilone also decreases Bcl-2 protein expression and induces cytoprotective autophagy in human hepatic carcinoma and glioma cells. In conclusion, this study not only provides a feasible and alternative way exploring new molecular mechanisms of drugs by combing computation DTI prediction, but also reveals an effective strategy to reinforce the antitumor efficacy of Ixabepilone.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Epotilonas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Epotilonas/síntese química , Epotilonas/química , Feminino , Humanos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
Theranostics ; 10(4): 1833-1848, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32042339

RESUMO

Purpose: To determine the role of UCH-L1 in regulating ERα expression, and to evaluate whether therapeutic targeting of UCH-L1 can enhance the efficacy of anti-estrogen therapy against breast cancer with loss or reduction of ERα. Methods: Expressions of UCH-L1 and ERα were examined in breast cancer cells and patient specimens. The associations between UCH-L1 and ERα, therapeutic response and prognosis in breast cancer patients were analyzed using multiple databases. The molecular pathways by which UCH-L1 regulates ERα were analyzed using immunoblotting, qRT-PCR, immunoprecipitation, ubiquitination, luciferase and ChIP assays. The effects of UCH-L1 inhibition on the efficacy of tamoxifen in ERα (-) breast cancer cells were tested both in vivo and in vitro. Results: UCH-L1 expression was conversely correlated with ERα status in breast cancer, and the negative regulatory effect of UCH-L1 on ERα was mediated by the deubiquitinase-mediated stability of EGFR, which suppresses ERα transcription. High expression of UCH-L1 was associated with poor therapeutic response and prognosis in patients with breast cancer. Up-regulation of ERα caused by UCH-L1 inhibition could significantly enhance the efficacy of tamoxifen and fulvestrant in ERα (-) breast cancer both in vivo and in vitro. Conclusions: Our results reveal an important role of UCH-L1 in modulating ERα status and demonstrate the involvement of UCH-L1-EGFR signaling pathway, suggesting that UCH-L1 may serve as a novel adjuvant target for treatment of hormone therapy-insensitive breast cancers. Targeting UCH-L1 to sensitize ER negative breast cancer to anti-estrogen therapy might represent a new therapeutic strategy that warrants further exploration.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Ubiquitina Tiolesterase/genética , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/metabolismo , Antagonistas de Estrogênios/uso terapêutico , Feminino , Fulvestranto/uso terapêutico , Humanos , Camundongos , Camundongos Nus , Tamoxifeno/uso terapêutico , Ubiquitina Tiolesterase/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
Front Pharmacol ; 11: 629266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33628188

RESUMO

DNA repair pathways are triggered to maintain genetic stability and integrity when mammalian cells are exposed to endogenous or exogenous DNA-damaging agents. The deregulation of DNA repair pathways is associated with the initiation and progression of cancer. As the primary anti-cancer therapies, ionizing radiation and chemotherapeutic agents induce cell death by directly or indirectly causing DNA damage, dysregulation of the DNA damage response may contribute to hypersensitivity or resistance of cancer cells to genotoxic agents and targeting DNA repair pathway can increase the tumor sensitivity to cancer therapies. Therefore, targeting DNA repair pathways may be a potential therapeutic approach for cancer treatment. A better understanding of the biology and the regulatory mechanisms of DNA repair pathways has the potential to facilitate the development of inhibitors of nuclear and mitochondria DNA repair pathways for enhancing anticancer effect of DNA damage-based therapy.

19.
Angew Chem Int Ed Engl ; 59(9): 3529-3533, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31863545

RESUMO

Polycyclic aromatic hydrocarbons with hexagons/pentagons or hexagons/heptagons have been intensively investigated in recent years, but those with simultaneous presence of hexagons, pentagons and heptagons remain rare. In this paper, we report dicyclohepta[ijkl,uvwx]rubicene (DHR), a non-benzenoid isomer of dibenzo[bc,kl]coronene with two pentagons and two heptagons. We developed an efficient and scalable synthetic method for DHR by using Scholl reaction and dehydrogenation. Crystal structure of DHR shows that the benzenoid rings, two pentagons and two heptagons are coplanar. The bond lengths analysis and the ICSS(1)zz and LOL-π calculations indicate that the incorporation of two formal azulene moieties has an effect on the conjugated structure. The π-electrons of benzenoid and pentagon rings are more delocalized. Cyclic voltammetry studies indicate that DHR shows multiple oxidation and reduction potentials. Interestingly, DHR exhibits unusual S0 to S2 absorption and abnormal anti-Kasha S2 to S0 emission. Moreover, crystals of DHR exhibit semiconducting behaviour with hole mobility up to 0.082 cm2 V-1 s-1 .

20.
Acta Pharmacol Sin ; 40(9): 1237-1244, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30914761

RESUMO

Eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has been shown to play an important role in modulating autophagy and apoptosis in tumor cells under various stresses. In this study, we investigated the regulatory role of eEF-2K in pyroptosis (a new form of programmed necrosis) in doxorubicin-treated human melanoma cells. We found that doxorubicin (0.5-5 µmol/L) induced pyroptosis in melanoma cell lines SK-MEL-5, SK-MEL-28, and A-375 with high expression of DFNA5, but not in human breast cancer cell line MCF-7 with little expression of DFNA5. On the other hand, doxorubicin treatment activated autophagy in the melanoma cells; inhibition of autophagy by transfecting the cells with siRNA targeting Beclin1 or by pretreatment with chloroquine (20 µmol/L) significantly augmented pyroptosis, thus sensitizing the melanoma cells to doxorubicin. We further demonstrated that doxorubicin treatment activated eEF-2K in the melanoma cells, and silencing of eEF-2K blunted autophagic responses, but promoted doxorubicin-induced pyroptotic cell death. Taken together, the above results demonstrate that eEF-2K dictates the cross-talk between pyroptosis and autophagy in doxorubicin-treated human melanoma cells; suppression of eEF-2K results in inhibiting autophagy and augmenting pyroptosis, thus modulating the sensitivity of melanoma cells to doxorubicin, suggesting that targeting eEF-2K may reinforce the antitumor efficacy of doxorubicin, offering a new insight into tumor chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Autofagia/fisiologia , Doxorrubicina/farmacologia , Quinase do Fator 2 de Elongação/metabolismo , Melanoma/metabolismo , Piroptose/fisiologia , Autofagia/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Humanos , Melanoma/tratamento farmacológico , Proteínas Associadas aos Microtúbulos/metabolismo , Piroptose/efeitos dos fármacos , Receptores de Estrogênio/metabolismo
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