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1.
J Virol ; 98(2): e0180123, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38193691

RESUMO

In mammals, NLRX1 is a unique member of the nucleotide-binding domain and leucine-rich repeat (NLR) family showing an ability to negatively regulate IFN antiviral immunity. Intron-containing genes, including NLRX1, have more than one transcript due to alternative splicing; however, little is known about the function of its splicing variants. Here, we identified a transcript variant of NLRX1 in zebrafish (Danio rerio), termed NLRX1-tv4, as a negative regulator of fish IFN response. Zebrafish NLRX1-tv4 was slightly induced by viral infection, with an expression pattern similar to the full-length NLRX1. Despite the lack of an N-terminal domain that exists in the full-length NLRX1, overexpression of NLRX1-tv4 still impaired fish IFN antiviral response and promoted viral replication in fish cells, similar to the full-length NLRX1. Mechanistically, NLRX1-tv4 targeted STING for proteasome-dependent protein degradation by recruiting an E3 ubiquitin ligase RNF5 to drive the K48-linked ubiquitination, eventually downregulating the IFN antiviral response. Mapping of NLRX1-tv4 domains showed that its N-terminal and C-terminal regions exhibited a similar potential to inhibit STING-mediated IFN antiviral response. Our findings reveal that like the full-length NLRX1, zebrafish NLRX-tv4 functions as an inhibitor to shape fish IFN antiviral response.IMPORTANCEIn this study, we demonstrate that a transcript variant of zebrafish NLRX1, termed NLRX1-tv4, downregulates fish IFN response and promotes virus replication by targeting STING for protein degradation and impairing the interaction of STING and TBK1 and that its N- and C-terminus exhibit a similar inhibitory potential. Our results are helpful in clarifying the current contradictory understanding of structure and function of vertebrate NLRX1s.


Assuntos
Proteínas de Membrana , Proteínas Mitocondriais , Proteínas de Peixe-Zebra , Animais , Imunidade Inata , Domínios Proteicos , Isoformas de Proteínas/genética , Ubiquitina-Proteína Ligases , Ubiquitinação , Peixe-Zebra/imunologia , Peixe-Zebra/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Membrana/metabolismo , Interferons/metabolismo
2.
Respir Res ; 25(1): 199, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720331

RESUMO

BACKGROUND: Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) remains a devastating clinical complication seriously affecting the therapeutic outcome of preterm infants. Hence, early prevention and timely diagnosis prior to pathological change is the key to reducing morbidity and improving prognosis. Our primary objective is to utilize machine learning techniques to build predictive models that could accurately identify BPD infants at risk of developing PH. METHODS: The data utilized in this study were collected from neonatology departments of four tertiary-level hospitals in China. To address the issue of imbalanced data, oversampling algorithms synthetic minority over-sampling technique (SMOTE) was applied to improve the model. RESULTS: Seven hundred sixty one clinical records were collected in our study. Following data pre-processing and feature selection, 5 of the 46 features were used to build models, including duration of invasive respiratory support (day), the severity of BPD, ventilator-associated pneumonia, pulmonary hemorrhage, and early-onset PH. Four machine learning models were applied to predictive learning, and after comprehensive selection a model was ultimately selected. The model achieved 93.8% sensitivity, 85.0% accuracy, and 0.933 AUC. A score of the logistic regression formula greater than 0 was identified as a warning sign of BPD-PH. CONCLUSIONS: We comprehensively compared different machine learning models and ultimately obtained a good prognosis model which was sufficient to support pediatric clinicians to make early diagnosis and formulate a better treatment plan for pediatric patients with BPD-PH.


Assuntos
Displasia Broncopulmonar , Hipertensão Pulmonar , Aprendizado de Máquina , Humanos , Displasia Broncopulmonar/diagnóstico , Recém-Nascido , Hipertensão Pulmonar/diagnóstico , Masculino , Feminino , Estudos Retrospectivos , Lactente Extremamente Prematuro , Recém-Nascido Prematuro
3.
Opt Lett ; 48(23): 6263-6266, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039242

RESUMO

A high-power regenerative amplifier (RA) based on dual-slab Yb:KGd(WO4)2 (Yb:KGW) was demonstrated, which provided a maximum average power of 33.7 W at a repetition rate of 75-200 kHz before compression with a central wavelength of 1039 nm, corresponding to an optical-to-optical conversion efficiency of 51.4%. To the best of our knowledge, this is the highest average power from the Yb:KGW solid-state RA. The compressed pulse duration of 205 fs was realized under the maximum output power. By adjusting the gain of the crystals, respectively, the spectral shaping can be achieved. A combination spectrum with root-mean-square (RMS) bandwidth of 4.5 nm was generated with a central wavelength of 1035 nm at an output power of 20 W, the compressed pulse duration was 159 fs. Meanwhile, effective mitigation of thermal effects by dual-slab configuration guaranteed the nearly diffraction-limited beam quality: M x2 = 1.17 and M y2 = 1.20.

4.
Mol Cell Biochem ; 476(7): 2729-2738, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33683556

RESUMO

Colon cancer is one of the most familiar malignancies worldwide, with high morbidity and high mortality. This study intended to explore the role and mechanism of tectoridin (TEC) in regulating the progression of colon cancer. First, colon cancer cell lines (HCT116 and SW480 cells) were treated with different doses of TEC (0-200 µM). Then, CCK8 and clone formation experiments were performed to detect cell proliferation. Flow cytometry and western blot were conducted to examine apoptosis. Subsequently, Transwell assay and wound-healing test was employed to determine the effect of TEC on colon cancer cell invasion and migration. Next, western blot was performed to monitor the PKC/p38 MAPK pathway activation. In addition, a tumor model was established in nude mice to explore the effect of TEC on tumor growth in vivo. TEC dose-dependently dampened the proliferation, migration and invasion of colon cancer cells and facilitated their apoptosis. In addition, TEC abated the tumor cell growth in vivo. Besides, TEC dose-dependently suppressed the expression of PKC and p38 MAPK. Moreover, inhibiting the PKC pathway almost cancel out the anti-tumor effects induced by TEC. TEC attenuates the colon cancer progression by inhibiting the PKC/p38 MAPK pathway.


Assuntos
Neoplasias do Colo/enzimologia , Regulação para Baixo/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Isoflavonas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Proteína Quinase C/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Células HCT116 , Humanos
5.
J Nanobiotechnology ; 19(1): 33, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514385

RESUMO

BACKGROUND: The outbreak and pandemic of coronavirus SARS-CoV-2 caused significant threaten to global public health and economic consequences. It is extremely urgent that global people must take actions to develop safe and effective preventions and therapeutics. Nanobodies, which are derived from single­chain camelid antibodies, had shown antiviral properties in various challenge viruses. In this study, multivalent nanobodies with high affinity blocking SARS-CoV-2 spike interaction with ACE2 protein were developed. RESULTS: Totally, four specific nanobodies against spike protein and its RBD domain were screened from a naïve VHH library. Among them, Nb91-hFc and Nb3-hFc demonstrated antiviral activity by neutralizing spike pseudotyped viruses in vitro. Subsequently, multivalent nanobodies were constructed to improve the neutralizing capacity. As a result, heterodimer nanobody Nb91-Nb3-hFc exhibited the strongest RBD-binding affinity and neutralizing ability against SARS-CoV-2 pseudoviruses with an IC50 value at approximately 1.54 nM. CONCLUSIONS: The present study indicated that naïve VHH library could be used as a potential resource for rapid acquisition and exploitation of antiviral nanobodies. Heterodimer nanobody Nb91-Nb3-hFc may serve as a potential therapeutic agent for the treatment of COVID-19.


Assuntos
Anticorpos de Domínio Único/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Sítios de Ligação , Células HEK293 , Humanos , Testes de Neutralização , Ligação Proteica , Domínios Proteicos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores
6.
Prostate ; 79(13): 1553-1562, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31294486

RESUMO

BACKGROUND: Previous studies had demonstrated that aldo-keto reductase family 1 member C3 (AKR1C3), a crucial enzyme in the steroidogenic pathway, played an important role in abiraterone (ABI)-resistance in metastatic castration-resistant prostate cancer (mCRPC) by increasing intratumoral androgen synthesis. However, its value in predicting treatment response in patients with mCRPC is unknown. METHOD AND MATERIALS: Data of 163 patients with metastatic prostate cancer between 2016 and 2018 were retrospectively analyzed. All patients received androgen deprivation therapy plus bicalutamide after initial diagnosis. After mCRPC, either ABI or docetaxel (DOC) treatment was used. No patient had the experience of therapy to the primary tumor. AKR1C3 protein was detected by immunohistochemical staining from rebiopsy (re-Bx) of primary prostate lesions at mCRPC. Kaplan-Meier curves and Cox regression were used to analyze the association between AKR1C3 and treatment outcomes. RESULTS: AKR1C3 was positive in 58 of 163 (35.6%) cases. AKR1C3 was associated with significantly shorter median prostate-specific antigen progression-free survival (mPSA-PFS, 5.6 mo vs 10.7 mo; P < .001), median radiographic progression-free survival (mrPFS, 11.1 mo vs 18.0 mo; P = .018), and numerically shorter median overall survival (mOS, 20.4 mo vs 26.4 mo; P = .157). Notably, AKR1C3-positive patients treated with ABI, but not DOC, had shorter mPSA-PFS and mrPFS compared with AKR1C3-negative men, (mPSA-PFS, 5.7 mo vs. 11.2 mo; P < .001; mrPFS, 12.4 mo vs 23.3 mo; P = .048). However, AKR1C3 expression had no correlation to PSA response or OS. Multivariate Cox regression indicated that AKR1C3 was independently accompanied with rapid PSA progression (hazard ratio [HR], 3.64; 95% confidence interval [CI], 2.10-6.31; P < 0.001) and radiological progression (HR, 2.08; 95% CI, 1.05-4.11; P = .036) in the ABI-treated subgroup. CONCLUSION: This study demonstrated that AKR1C3 detection in tissues from prostate re-Bx at mCRPC was associated with early resistance to ABI but not DOC. These results will help to make optimal personalized treatment decisions for patients with mCRPC, facilitate physicians predicting the effectiveness of ABI.


Assuntos
Membro C3 da Família 1 de alfa-Ceto Redutase/metabolismo , Androstenos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/enzimologia , Idoso , Membro C3 da Família 1 de alfa-Ceto Redutase/biossíntese , Androstenos/administração & dosagem , Androstenos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Docetaxel/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Humanos , Biópsia Guiada por Imagem , Imuno-Histoquímica , Masculino , Metástase Neoplásica , Prednisona/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/patologia , Estudos Retrospectivos
7.
Exp Cell Res ; 371(1): 50-62, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30055135

RESUMO

DESI2 is a novel pro-apoptotic gene. We previously reported that DESI2 overexpression induces S phase arrest and apoptosis by activating checkpoint kinases. This work was to test whether the combination of endostatin, an endogenous antiangiogenic inhibitor, with DESI2 could improve the therapy efficacy in vitro and in vivo. The recombinant plasmid co-expressing DESI2 and endostatin was encapsulated with DOTAP/Cholesterol cationic liposome. Mice bearing CT26 colon carcinoma and LL2 lung cancer were treated with the DNA-liposome complex. We found that, in vitro, the combination of DESI2 and endostatin more efficiently inhibited proliferation of CT26, LL2, HCT116 and A549 cancer cells via apoptosis, as assessed by MTT assay, colony-formation assays, flow cytometric analysis, hoechst staining and activation of caspase-3, respectively. In addition, DESI2 overexpression caused up-regulation of RPS7, a substrate of DESI2 deubiquitination. Furthermore, siRNA targeting RPS7 partially abrogated, whereas RPS7 overexpression enhanced DESI2-induced inhibition of cell proliferation. Importantly, the combination also caused DNA lesions accumulation, which further promotes apoptosis. Mechanistic rationale suggested that endostatin first inhibits DNA-PKcs kinase, and partly abrogated DESI2-induced phosphorylation of DNA-PKcs, leading to increase of DNA damage, then contributes to DESI2-induced apoptosis. In vivo, the combined gene therapy more significantly inhibited tumor growth and efficiently prolonged the survival of tumor bearing mice than mono therapy. The improved antitumor effect was associated with inhibition of cell proliferation via apoptosis, as analyzed by TUNEL assay and PCNA immunostaining. The combination also inhibited angiogenesis, as assessed by alginate-encapsulated tumor cell assay and CD31 staining. Our data suggest that the combined gene therapy of DESI2 and endostatin can significantly enhance the antitumor activity as a DNA lesions accumulator, apoptosis inducer and angiogenesis inhibitor. The present study may provide a novel method for the treatment of cancer.


Assuntos
Carbono-Nitrogênio Liases/genética , Neoplasias do Colo/genética , Endostatinas/genética , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Neoplasias Pulmonares/genética , Plasmídeos/metabolismo , Células A549 , Inibidores da Angiogênese/química , Inibidores da Angiogênese/metabolismo , Animais , Apoptose/genética , Carbono-Nitrogênio Liases/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Proliferação de Células , Colesterol/química , Colesterol/metabolismo , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Fragmentação do DNA , Endostatinas/metabolismo , Ácidos Graxos Monoinsaturados/química , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Células HCT116 , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Camundongos , Camundongos Endogâmicos C57BL , Plasmídeos/administração & dosagem , Plasmídeos/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Ribossômicas/antagonistas & inibidores , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Transdução de Sinais , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Exp Cell Res ; 366(1): 24-33, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29522753

RESUMO

PTEN deficiency often causes defects in DNA damage repair. Currently, effective therapies for breast cancer are lacking. ATM is an attractive target for cancer treatment. Previous studies suggested a synthetic lethality between PTEN and PARP. However, the synthetically lethal interaction between PTEN and ATM in breast cancer has not been reported. Moreover, the mechanism remains elusive. Here, using KU-60019, an ATM kinase inhibitor, we investigated ATM inhibition as a synthetically lethal strategy to target breast cancer cells with PTEN defects. We found that KU-60019 preferentially sensitizes PTEN-deficient MDA-MB-468 breast cancer cells to cisplatin, though it also slightly enhances sensitivity of PTEN wild-type breast cancer cells. The increased cytotoxic sensitivity is associated with apoptosis, as evidenced by flow cytometry and PARP cleavage. Additionally, the increase of DNA damage accumulation due to the decreased capability of DNA repair, as indicated by γ-H2AX and Rad51 foci, also contributed to this selective cytotoxicity. Mechanistically, compared with PTEN wild-type MDA-MB-231 cells, PTEN-deficient MDA-MB-468 cells have lower level of Rad51, higher ATM kinase activity, and display the elevated level of DNA damage. Moreover, these differences could be further enlarged by cisplatin. Our findings suggest that ATM is a promising target for PTEN-defective breast cancer.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Cisplatino/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Humanos , Células MCF-7 , Morfolinas/farmacologia , Tioxantenos/farmacologia
9.
BMC Cancer ; 18(1): 101, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29378532

RESUMO

BACKGROUND: The prognosis of hepatocellular carcinoma with portal vein tumor thrombus remains extremely poor. This pilot study aimed to evaluate the technical feasibility, effectiveness and safety of transcatheter chemoembolization for tumors in the liver parenchyma plus intra-arterial ethanol embolization for portal vein tumor thrombus. METHODS: A pilot study was carried out on 31 patients in the treatment group (transcatheter chemoembolization plus intra-arterial ethanol embolization) and 57 patients in the control group (transcatheter chemoembolization alone). Enhanced computed tomography/magnetic resonance images were repeated 4 weeks after the procedure to assess the response. Overall survival and complications were assessed until the patient died or was lost to follow-up. RESULTS: Median survival was 10.5 months in the treatment group (2.4 ± 1.7 courses) and 3.9 months in the control group (1.9 ± 1 courses) (P = 0.001). Patients in the treatment group had better overall survival (at 3, 6 and 12 months, respectively), compared to patients in the control group (90.3% vs. 59.6%, 64.5% vs. 29.8%, and 41.9% vs. 10.6%; p = 0.001). Furthermore, the rate of portal vein tumor thrombus regression was higher in the treatment group (93.1%) than in the control group (32.1%) (P < 0.001). CONCLUSIONS: Based on the results of this study, transcatheter chemoembolization combined with intra-arterial ethanol embolization may be more effective than transcatheter chemoembolization alone for treating hepatocellular carcinoma with portal vein tumor thrombus. Intra-arterial ethanol embolization for treating portal vein tumor thrombus is safe, feasible and prolongs overall survival.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Trombose Venosa/tratamento farmacológico , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Tomografia Computadorizada de Feixe Cônico , Etanol/administração & dosagem , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Veia Porta/efeitos dos fármacos , Veia Porta/patologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/patologia
10.
BMC Cancer ; 17(1): 167, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28253859

RESUMO

BACKGROUND: Recently studies have demonstrated that the long non-coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) may participate in the development and progression of lung cancer. In this study, we hypothesized that genetic variant of this lncRNA may affect the prognosis of lung cancer patients. METHODS: We conducted a follow-up study for 538 patients with non-small cell lung carcinoma (NSCLC), including 140 early-staged (stage I and II) and 398 advanced staged (stage III and IV) patients. The genetic variant rs3200401 in MALAT1 was then genotyped among this population by using TaqMan assay. The association of this variant with overall survival of these patients was further analyzed. RESULTS: It was shown that among the advanced lung adenoma patients, subjects carrying rs3200401 CT and CT + TT genotypes had significantly longer median survival time (MST = 29.9, 28.9 vs. 19.3 month, Long-rank P = 0.019 and 0.024, respectively) and decreased death risks [crude HR (95% CI) = 0.65 (0.43-0.98) and 0.64 (0.44-0.95), P = 0.040 and 0.025, respectively], when compared to subjects wtih the MALAT1 rs3200401 CC genotype. However, the beneficial effect of rs3200401 was not seen among early NSCLC and advanced lung squamous cell carcinoma patients. We further tested the TCGA data, and found that a higher expression of MALAT1 was associated with metastatic of advanced lung adenocarcinoma but not with lung squamous cell carcinoma. CONCLUSIONS: The rs3200401 T allele located on the lncRNA MALAT1 was associated with a better survival for advanced lung adenocarcinoma patients, which may offer a novel prognostic biomarker for this patient subgroup. However, these results need to be validated in larger populations of lung cancer and the biological function of this variant still warrants further investigation.


Assuntos
Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Prognóstico , Modelos de Riscos Proporcionais
11.
Br J Neurosurg ; 31(6): 638-640, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27416304

RESUMO

Langerhans cell histiocytosis (LCH) is a rare disease, and involvement of the atlas is extremely uncommon. Biopsy of atlas lesions is difficult and risky. In this case report, we describe the performance of percutaneous computed tomography-guided biopsy of an atlantal LCH in a patient with no complication.


Assuntos
Atlas Cervical/patologia , Histiocitose de Células de Langerhans/patologia , Doenças Raras/patologia , Doenças da Coluna Vertebral/patologia , Humanos , Biópsia Guiada por Imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
12.
J Biol Chem ; 290(24): 14927-44, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-25918161

RESUMO

PNAS-4, a novel pro-apoptotic gene, was activated during the early response to DNA damage. Our previous study has shown that PNAS-4 induces S phase arrest and apoptosis when overexpressed in A549 lung cancer cells. However, the underlying action mechanism remains far from clear. In this work, we found that PNAS-4 expression in lung tumor tissues is significantly lower than that in adjacent lung tissues; its expression is significantly increased in A549 cells after exposure to cisplatin, methyl methane sulfonate, and mitomycin; and its overexpression induces S phase arrest and apoptosis in A549 (p53 WT), NCI-H460 (p53 WT), H526 (p53 mutation), and Calu-1 (p53(-/-)) lung cancer cells, leading to proliferation inhibition irrespective of their p53 status. The S phase arrest is associated with up-regulation of p21(Waf1/Cip1) and inhibition of the Cdc25A-CDK2-cyclin E/A pathway. Up-regulation of p21(Waf1/Cip1) is p53-independent and correlates with activation of ERK. We further showed that the intra-S phase checkpoint, which occurs via DNA-dependent protein kinase-mediated activation of Chk1 and Chk2, is involved in the S phase arrest and apoptosis. Gene silencing of Chk1/2 rescues, whereas that of ATM or ATR does not affect, S phase arrest and apoptosis. Furthermore, human PNAS-4 induces DNA breaks in comet assays and γ-H2AX staining. Intriguingly, caspase-dependent cleavage of Chk1 has an additional role in enhancing apoptosis. Taken together, our findings suggest a novel mechanism by which elevated PNAS-4 first causes DNA-dependent protein kinase-mediated Chk1/2 activation and then results in inhibition of the Cdc25A-CDK2-cyclin E/A pathway, ultimately causing S phase arrest and apoptosis in lung cancer cells.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Apoptose/fisiologia , Quinase do Ponto de Checagem 2/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Quinases/metabolismo , Fase S/fisiologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Sequência de Bases , Carbono-Nitrogênio Liases , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2/genética , Dano ao DNA , Primers do DNA , Ativação Enzimática , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo , Proteínas Quinases/genética , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
World J Surg Oncol ; 13: 96, 2015 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-25889181

RESUMO

BACKGROUND: Radiofrequency ablation (RFA) and percutaneous ethanol injection (PEI) are treatment methods for patients with early-stage hepatocellular carcinoma (HCC) who are not suitable for surgery. Although some reports indicate that RFA is better than PEI, results from previous reviews and analyses are inconsistent. Therefore, this meta-analysis was performed to more thoroughly evaluate the effects of these treatments in patients with HCC. METHODS: A literature search was conducted using the Excerpta Medica dataBASE, PubMed, the Cochrane Library, the American Society of Clinical Oncology database, the China National Knowledge Infrastructure database, the Wanfang database, the Chinese Biomedical Literature Database, and the Chongqing VIP database without language limitations. The primary outcome evaluated was overall survival, and secondary outcomes included complete response and local recurrence. Comparisons were made between Asian and European studies. RESULTS: Total pooled and subgroup analyses of Asian studies that included selection biases revealed that RFA is superior to PEI with respect to overall survival (hazard ratio (HR), 0.54; 95% confidence interval (CI), 0.37 to 0.80; P < 0.01) and complete response (relative risk (RR), 1.10; 95% CI 1.03 to 1.18; P < 0.01). However, no significant difference was observed between RFA and PEI in the European studies. In Asian studies, RFA was associated with a lower local recurrence rate than PEI at 1 year (RR, 0.44; 95% CI 0.20 to 0.95; P < 0.05) and 3 years (RR, 0.35; 95% CI 0.22 to 0.55; P < 0.01). However, local recurrence was significantly lower after only 3 years in European studies (RR, 0.50; 95% CI 0.32 to 0.78; P < 0.05). CONCLUSIONS: RFA was only superior to PEI in Asian studies that included selection bias. Thus, there is insufficient evidence to support the idea that RFA is superior to PEI for patients with cirrhotic HCC. Additional large-scale, multicenter, randomized controlled trials that control for selection bias are needed to fully elucidate the optimal treatment method for HCC.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Carcinoma Hepatocelular/terapia , Ablação por Cateter , Etanol/administração & dosagem , Neoplasias Hepáticas/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Injeções , Prognóstico
14.
Angew Chem Int Ed Engl ; 54(31): 9075-8, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26096517

RESUMO

An ortho-selective C-F bond borylation between N-heterocycle-substituted polyfluoroarenes and Bpin-Bpin with simple and commercially available [Rh(cod)2 ]BF4 as a catalyst is now reported. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, even toward monofluoroarene, thus providing a facile access to a wide range of borylated fluoroarenes that are useful for photoelectronic materials. Preliminary mechanistic studies reveal that a Rh(III/V) catalytic cycle via a key intermediate rhodium(III) hydride complex [(H)Rh(III) Ln (Bpin)] may be involved in the reaction.

15.
J Am Chem Soc ; 136(4): 1230-3, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24417183

RESUMO

A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high α/γ-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.


Assuntos
Alcenos/química , Compostos de Boro/química , Hidrocarbonetos Halogenados/química , Hidrocarbonetos Halogenados/síntese química , Compostos Organometálicos/química , Paládio/química , Catálise , Estrutura Molecular
16.
Angew Chem Int Ed Engl ; 53(37): 9909-13, 2014 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-25044391

RESUMO

Transition-metal-catalyzed difluoroalkylation of aromatics remains challenging despite the importance of difluoroalkylated arenes in medicinal chemistry. Herein, the first successful example of nickel-catalyzed difluoroalkylation of aryl boronic acids is described. The reaction allows access to a variety of functionalized difluoromethyl bromides and chlorides, and paves the way to highly cost-efficient synthesis of a wide range of difluoroalkylated arenes. The notable features of this protocol are its high generality, excellent functional-group compatibility, low-cost nickel-catalyst, and practicality for gram-scale production, thus providing a facile method for applications in drug discovery and development.


Assuntos
Flúor/química , Níquel/química , Ácidos Borônicos , Catálise , Modelos Moleculares , Estrutura Molecular
17.
Biomolecules ; 14(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38254706

RESUMO

Acute T-lymphoblastic leukemia (T-ALL) is a type of leukemia that can occur in both pediatric and adult populations. Compared to acute B-cell lymphoblastic leukemia (B-ALL), patients with T-cell T-ALL have a poorer therapeutic efficacy. In this study, a novel anti-CD7 antibody-drug conjugate (ADC, J87-Dxd) was successfully generated and used for T-ALL treatment. Firstly, to obtain anti-CD7 mAbs, we expressed and purified the CD7 protein extracellular domain. Utilizing hybridoma technology, we obtained three anti-CD7 mAbs (J87, G73 and A15) with a high affinity for CD7. Both the results of immunofluorescence and Biacore assay indicated that J87 (KD = 1.54 × 10-10 M) had the highest affinity among the three anti-CD7 mAbs. In addition, an internalization assay showed the internalization level of J87 to be higher than that of the other two mAbs. Next, we successfully generated the anti-CD7 ADC (J87-Dxd) by conjugating DXd to J87 via a cleavable maleimide-GGFG peptide linker. J87-Dxd also possessed the ability to recognize and bind CD7. Using J87-Dxd to treat T-ALL cells (Jurkat and CCRF-CEM), we observed that J87-Dxd bound to CD7 was internalized into T-ALL cells. Moreover, J87-Dxd treatment significantly induced the apoptosis of Jurkat and CCRF-CEM cells. The IC50 (half-maximal inhibitory concentration) value of J87-Dxd against CCRF-CEM obtained by CCK-8 assay was 6.3 nM. Finally, to assess the antitumor efficacy of a J87-Dxd in vivo, we established T-ALL mouse models and treated mice with J87-Dxd or J87. The results showed that on day 24 after tumor inoculation, all mice treated with J87 or PBS died, whereas the survival rate of mice treated with J87-Dxd was 80%. H&E staining showed no significant organic changes in the heart, liver, spleen, lungs and kidneys of all mice. In summary, we demonstrated that the novel anti-CD7 ADC (J87-Dxd) had a potent and selective effect against CD7-expressing T-All cells both in vitro and in vivo, and could thus be expected to be further developed as a new drug for the treatment of T-ALL or other CD7-expression tumors.


Assuntos
Linfoma de Burkitt , Imunoconjugados , Leucemia-Linfoma Linfoblástico de Células Precursoras , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Adulto , Animais , Criança , Humanos , Camundongos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Imunoconjugados/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Antígenos CD7/imunologia , Antígenos CD7/uso terapêutico
18.
Zhongguo Zhen Jiu ; 44(5): 569-73, 2024 May 12.
Artigo em Zh | MEDLINE | ID: mdl-38764108

RESUMO

The paper introduces professor LU Yonghui 's academic thought and clinical experience in treating benign prostatic hyperplasia (BPH). It is believed that the pathogenesis of BPH includes retarded qi movement of triple energizers and dysfunction of the bladder in qi activity, resulting in impairment of water metabolism, and difficulty in micturition occurs. In treatment, acupuncture is delivered at the muscle region (membrane) of the body to promote qi circulation. The needles are inserted at the acupoints of conception vessel to different depths. The shallow insertion is operated at Qihai (CV 6) and Guanyuan (CV 4) to benefit qi movement of triple energizers, the moderate insertion is at Zhongji (CV 3), the front-mu point of the bladder, to benefit the intersections (membranes) of triple energizers, and the deep insertion is at Qugu (CV 2) to work at the internal organ, regulate qi, remove obstruction. As a result, the qi movement of triple energizers is improved, the function of the bladder in qi activity recovered, urination ameliorated and the retention of urine cured.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Hiperplasia Prostática , Humanos , Hiperplasia Prostática/terapia , Hiperplasia Prostática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Idoso
19.
Future Med Chem ; 16(9): 887-903, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38618977

RESUMO

Background: The epidemic caused by SARS-CoV-2 swept the world in 2019. The 3C-like protease (3CLpro) of SARS-CoV-2 plays a key role in viral replication, and its inhibition could inhibit viral replication. Materials & methods: The virtual screen based on receptor-ligand pharmacophore models and molecular docking were conducted to obtain the novel scaffolds of the 3CLpro. The molecular dynamics simulation was also carried out. All compounds were synthesized and evaluated in biochemical assays. Results: The compound C2 could inhibit 3CLpro with a 72% inhibitory rate at 10 µM. The covalent docking showed that C2 could form a covalent bond with the Cys145 in 3CLpro. Conclusion: C2 could be a potent lead compound of 3CLpro inhibitors against SARS-CoV-2.


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Assuntos
Antivirais , Proteases 3C de Coronavírus , Desenho de Fármacos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , SARS-CoV-2 , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/síntese química , Antivirais/química , Humanos , Inibidores de Proteases/farmacologia , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , Tratamento Farmacológico da COVID-19 , Relação Estrutura-Atividade
20.
Biochem Pharmacol ; 221: 116040, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311257

RESUMO

Paclitaxel is widely used to treat cancer, however, drug resistance limits its clinical utility. STAT3 is constitutively activated in some cancers, and contributes to chemotherapy resistance. Currently, several STAT3 inhibitors including WP1066 are used in cancer clinical trials. However, whether WP1066 reverses paclitaxel resistance and the mechanismremains unknown. Here, we report that in contrast to paclitaxel-sensitive parental cells, the expressions of several pro-survival BCL2 family members such as BCL-2, BCL-XL and MCL-1 are higher in paclitaxel-resistant ovarian cancer cells. Meanwhile, STAT3 is constitutively activated while stathmin loses its activity in paclitaxel-resistant cells. Importantly, WP1066 amplifies the inhibition of cell proliferation, colony-forming ability and apoptosis of ovarian cancer cells induced by paclitaxel. Mechanistically, WP1066, on the one hand, interferes the STAT3/Stathmin interaction, causing unleash of STAT3/Stathmin from microtubule, thus destroying microtubule stability. This process results in reduction of Ac-α-tubulin, further causing MCL-1 reduction. On the other hand, WP1066 inhibits phosphorylation of STAT3 by JAK2, and blocks its nuclear translocation, therefore repressing the transcription of pro-survival targets such as BCL-2, BCL-XL and MCL-1. Finally, the two pathways jointly promote cell death. Our findings reveal a new mechanism wherein WP1066 reverses paclitaxel-resistance of ovarian cancer cells by dually inhibiting STAT3 activity and STAT3/Stathmin interaction, which may layfoundation for WP1066 combined with paclitaxel in treating paclitaxel-resistant ovarian cancer.


Assuntos
Neoplasias Ovarianas , Paclitaxel , Piridinas , Tirfostinas , Humanos , Feminino , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Proteína de Sequência 1 de Leucemia de Células Mieloides , Estatmina/metabolismo , Transdução de Sinais , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Transcrição STAT3/metabolismo
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