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1.
Mol Cell ; 57(6): 971-983, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25684209

RESUMO

DNA methylation is a conserved epigenetic mark that plays important roles in plant and vertebrate development, genome stability, and gene regulation. Canonical Methyl-CpG-binding domain (MBD) proteins are important interpreters of DNA methylation that recognize methylated CG sites and recruit chromatin remodelers, histone deacetylases, and histone methyltransferases to repress transcription. Here, we show that Arabidopsis MBD7 and Increased DNA Methylation 3 (IDM3) are anti-silencing factors that prevent gene repression and DNA hypermethylation. MBD7 preferentially binds to highly methylated, CG-dense regions and physically associates with other anti-silencing factors, including the histone acetyltransferase IDM1 and the alpha-crystallin domain proteins IDM2 and IDM3. IDM1 and IDM2 were previously shown to facilitate active DNA demethylation by the 5-methylcytosine DNA glycosylase/lyase ROS1. Thus, MBD7 tethers the IDM proteins to methylated DNA, which enables the function of DNA demethylases that in turn limit DNA methylation and prevent transcriptional gene silencing.


Assuntos
Proteínas de Arabidopsis/metabolismo , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Inativação Gênica , Proteínas de Arabidopsis/genética , Sítios de Ligação , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Plantas Geneticamente Modificadas
2.
Acta Cardiol Sin ; 38(1): 1-12, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35068877

RESUMO

Advances in cancer management have significantly improved survival in patients with cancers. Cardiovascular complications of cancer treatment are becoming significant competing causes of death in these patients. Radiotherapy is an indispensable component of cancer treatment, and irradiation of the heart and vasculature during cancer radiotherapy is now recognized as a new risk factor for cardiovascular diseases. It is important to involve multidisciplinary expertise and provide practical recommendations to promote awareness, recognize risks, and provide adequate interventions without jeopardizing cancer control. In this consensus paper, experts from the Taiwan Society for Therapeutic Radiology and Oncology and Taiwan Society of Cardiology provide a focused update on the clinical practice for risk stratification and management of radiation-induced cardiovascular disease (RICVD). We believe that implementing RICVD care under a collaborative cardio-oncology program will significantly improve cancer treatment outcomes and will facilitate high quality clinical investigations.

3.
BMC Oral Health ; 21(1): 29, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441108

RESUMO

BACKGROUND: High quality lymph node (LN) yield could increase survival, however strategies to improve LN yield have been seldom reported. This study aimed to assess the multiple-step action to promote quality of neck dissection in oral cancer. METHODS: A total of 400 patients with oral cancer who underwent primary tumor resection and neck dissection, including elective and radical neck dissection, were recruited after propensity score matching by clinical T and N categories between January 2009 and September 2018. Patients were treated by two independent departments in our institute. A multiple-step action was initiated in October 2015 in one department, and another department was as a control group. The impact of multiple-step action on LN yield and regional recurrence were analyzed using multivariate analysis and difference-in-differences (DID) linear regression analysis. RESULTS: The mean patient age was 55.2 + 11.1 years, and 92% were male. A total of 180 (45%) patients had T3-4 disease, and 129 (32%) patients had N2-3 disease. The multivariate linear regression and DID analyses revealed that multiple-step action had a positive effect on LN yield. A net improvement of LN yield with a coefficient of 13.78 (p < 0.001) after launching multiple-step action (since October 2015) was observed. A borderline protective effect of multiple-step action for cN0 patients with a reduced regional recurrence rate of 11.6% (p = 0.072) through DID analysis was noted. CONCLUSIONS: Multiple-step action was associated with increased LN yield and decreased regional recurrence in patients with oral cancer. The observed activity may promote surgeons to improve the quality of neck dissections, is feasible, and could be applied to a widespread patient population.


Assuntos
Neoplasias Bucais , Recidiva Local de Neoplasia , Adulto , Idoso , Feminino , Humanos , Linfonodos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/cirurgia , Esvaziamento Cervical , Estudos Retrospectivos
4.
Bioorg Chem ; 100: 103875, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380342

RESUMO

SHP2 is a non-receptor protein tyrosine phosphatase encoded by the PTPN11 gene, which affects the transduction of multiple signaling pathways, including RAS-ERK, PI3K-AKT and JAK-STAT. SHP2 also plays an important role in the programmed cell death pathway (PD-1/PD-L1). Studies have shown that SHP2 is associated with a variety of cancers, including breast, liver and gastric cancers. Therefore, the development of SHP2 inhibitors has attracted extensive attention. In this study, based on the known inhibitor 1 (SHP099), novel SHP2 inhibitors were designed by means of scaffold hopping, and 35 pyridine derivatives as SHP2 inhibitors were found. The in vitro enzyme activity assay was performed on these compounds, and multiple selective SHP2 inhibitors with activity potency similar to that of SHP099 were obtained. Among them, compound (2-(4-(aminomethyl)piperidin-1-yl)-5-(2,3-dichlorophenyl)pyridin-3-yl)methanol (11a) was the most potent and highly selective SHP2 inhibitor with an in vitro enzyme activity IC50 value of 1.36 µM. Fluorescence titration assay verified that 11a bound directly to SHP2 protein. Subsequently, cell assay of representative compounds showed that these compounds could effectively inhibit the proliferation of Ba/F3 cells. In addition, the pharmacokinetic characteristics of the designed compounds were analyzed by the in silico ADMET prediction. Molecular docking study provided more detailed information on the binding mode of compounds and SHP2 protein. In brief, this study reported for the first time that pyridine derivatives as novel SHP2 inhibitors had good inhibitory activity and selectivity, providing new clues for the development of small molecule SHP2 inhibitors.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Piridinas/química , Piridinas/farmacologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Humanos , Camundongos , Modelos Biológicos , Simulação de Acoplamento Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Piridinas/síntese química , Piridinas/farmacocinética
5.
J Cell Biochem ; 120(10): 17015-17029, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31125141

RESUMO

Diabetic macular edema, also known as diabetic eye disease, is mainly caused by the overexpression of vascular endothelial protein tyrosine phosphatase (VE-PTP) at hypoxia/ischemic. AKB-9778 is a known VE-PTP inhibitor that can effectively interact with the active site of VE-PTP to inhibit the activity of VE-PTP. However, the binding pattern of VE-PTP with AKB-9778 and the dynamic implications of AKB-9778 on VE-PTP system at the molecular level are poorly understood. Through molecular docking, it was found that the AKB-9778 was docked well in the binding pocket of VE-PTP by the interactions of hydrogen bond and Van der Waals. Furthermore, after molecular dynamic simulations on VE-PTP system and VE-PTP AKB-9778 system, a series of postdynamic analyses found that the flexibility and conformation of the active site undergone an obvious transition after VE-PTP binding with AKB-9778. Moreover, by constructing the RIN, it was found that the different interactions in the active site were the detailed reasons for the conformational differences between these two systems. Thus, the finding here might provide a deeper understanding of AKB-9778 as VE-PTP Inhibitor.


Assuntos
Compostos de Anilina/química , Inibidores Enzimáticos/química , Hipoglicemiantes/química , Simulação de Acoplamento Molecular , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/química , Ácidos Sulfônicos/química , Motivos de Aminoácidos , Compostos de Anilina/metabolismo , Domínio Catalítico , Inibidores Enzimáticos/metabolismo , Humanos , Ligação de Hidrogênio , Hipoglicemiantes/metabolismo , Cinética , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/antagonistas & inibidores , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Ácidos Sulfônicos/metabolismo , Termodinâmica
6.
J Comput Aided Mol Des ; 33(8): 759-774, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31300938

RESUMO

SHP2 phosphatase, encoded by the PTPN11 gene, is a non-receptor PTP, which plays an important role in growth factor, cytokine, integrin, hormone signaling pathways, and regulates cellular responses, such as proliferation, differentiation, adhesion migration and apoptosis. Many studies have reported that upregulation of SHP2 expression is closely related to human cancer, such as breast cancer, liver cancer and gastric cancer. Hence, SHP2 has become a promising target for cancer immunotherapy. In this paper, we reported the identification of compound 1 as SHP2 inhibitor. Fragment-based ligand design, De novo design, ADMET and Molecular docking were performed to explore potential selective SHP2 allosteric inhibitors based on SHP836. The results of docking studies indicated that the selected compounds had higher selective SHP2 inhibition than existing inhibitors. Compound 1 was found to have a novel selectivity against SHP2 with an in vitro enzyme activity IC50 value of 9.97 µM. Fluorescence titration experiment confirmed that compound 1 directly bound to SHP2. Furthermore, the results of binding free energies demonstrated that electrostatic energy was the primary factor in elucidating the mechanism of SHP2 inhibition. Dynamic cross correlation studies also supported the results of docking and molecular dynamics simulation. This series of analyses provided important structural features for designing new selective SHP2 inhibitors as potential drugs and promising candidates for pre-clinical pharmacological investigations.


Assuntos
Inibidores Enzimáticos/química , Neoplasias/tratamento farmacológico , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Proteína Tirosina Fosfatase não Receptora Tipo 11/ultraestrutura
7.
J Integr Plant Biol ; 61(12): 1224-1242, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30652405

RESUMO

DNA methylation confers epigenetic regulation on gene expression and thereby on various biological processes. Tomato has emerged as an excellent system to study the function of DNA methylation in plant development. To date, regulation and function of DNA methylation maintenance remains unclear in tomato plants. Here, we report the critical function of tomato (Solanum lycopersicum) Methyltransferase 1 (SlMET1) in plant development and DNA methylome and transcriptome regulation. Using CRISPR-Cas9 gene editing, we generated slmet1 mutants and observed severe developmental defects with a frame-shift mutation, including small and curly leaves, defective inflorescence, and parthenocarpy. In leaf tissues, mutations in SlMET1 caused CG hypomethylation and CHH hypermethylation on a whole-genome scale, leading to a disturbed transcriptome including ectopic expression of many RIN target genes such as ACC2 in leaf tissues, which are normally expressed in fruits. Neither the CG hypomethylation nor CHH hypermethylation in the slmet1 mutants is related to tissue culture. Meanwhile, tissue culture induces non-CG hypomethylation, which occurs more frequently at gene regions than at TE regions. Our results depict SlMET1- and tissue culture-dependent tomato DNA methylomes, and that SlMET1 is required for maintaining a normal transcriptome and normal development of tomato.


Assuntos
Metilação de DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Metiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/genética , Transcriptoma/genética , Sequência de Bases , Ilhas de CpG/genética , Meio Ambiente , Edição de Genes , Pleiotropia Genética , Genoma de Planta , Solanum lycopersicum/enzimologia , Mutação/genética , Fenótipo , Transcrição Gênica
8.
J Nematol ; 512019.
Artigo em Inglês | MEDLINE | ID: mdl-34179810

RESUMO

Plant parasitic nematodes (PPN) are microscopic soil herbivores that cause damage to many economic crops. For the last century, it has been proposed that chemotaxis is the primary means by which PPN locate host plant roots. The identities and modes of action of chemoattractants that deliver host-specific messages to PPN, however, are still elusive. In this study, a unique multidimensional agar-based motility assay was developed to assess the impacts of root exudates on the short-range motility and orientation of PPN. Three PPN (Rotylenchulus reniformis, Meloidogyne incognita and Heterodera glycines) and root exudates from their respective host and non-host plants (cotton, soybean, and peanut) were used to validate the assay. As predicted, R. reniformis and M. incognita were attracted to root exudates of cotton and soybean (hosts), but not to the exudates of peanut (non-host). Likewise, H. glycines was attracted to soybean (host) root exudates. These results underpinned the intrinsic roles of root exudates in conveying the host specificity of PPN. In particular, PPN selectively identified and targeted to hydrophilic, but not hydrophobic, fractions of root exudates, indicating that groundwater should be an effective matrix for chemotaxis associated with PPN and their host plant interactions.

9.
Breast Cancer Res ; 20(1): 25, 2018 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-29661250

RESUMO

BACKGROUND: The isocitrate dehydrogenase (IDH) gene family expresses key functional metabolic enzymes in the Krebs cycle and mediates the epigenetic reprogramming, which serves as an important biomarker of breast cancer. However, the expression levels of the IDH protein and their biological function in human breast cancer remain largely unknown. METHODS: In this study, the clinical impact of IDH1 expression on the progression and prognosis of breast cancer was evaluated using immunohistochemistry assay (IHC) of the corresponding tumor-adjacent normal, ductal carcinoma in situ (DCIS), and invasive ductal carcinoma (IDC) tissues from 309 patients with breast ductal carcinoma. The relationship between microRNA (miRNA) and IDH1 were examined by a bioinformatics approach, western blot and reporter assay. The biological functions of IDH1 were examined in breast cancer cells with IDH1 knockdown, including proliferation, migration and invasion. RESULTS: The present findings revealed that the mRNA and protein expression levels of IDH1 were both significantly lower in breast cancer tissues than in adjacent normal tissues. A low expression level of IDH1 in breast cancer significantly correlated with advanced stage (p = 0.012), lymph node metastasis (p = 0.018), and poor disease-specific survival (DSS) (adjusted hazard ratio (AHR), 1.57, 95% confidence interval (CI), 1.08-2.30; p = 0.02). Furthermore, oncogenic miR-32 and miR-92b were identified to suppress IDH1 expression, leading to the inhibition of cell migration and invasion. We further explored whether reduced expression of IDH1 significantly increases snail expression by activating HIFα (hypoxia-inducible factor-1 alpha) and NFκB (nuclear factor kappa B) signaling. Multivariate Cox regression analysis revealed that the combination of low IDH1 and high snail expression could be an independent risk factor for shorter DSS (AHR, 2.34; 95% CI, 1.32-4.16; p = 0.004) and shorter disease-free survival (AHR, 2.50; 95% CI, 1.39-4.50; p = 0.002) in patients with breast cancer. CONCLUSION: Our findings revealed that a IDH1low/Snailhigh molecular signature could serve as an independent biomarker for poor prognosis in breast cancer.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Isocitrato Desidrogenase/genética , Fatores de Transcrição da Família Snail/genética , Adulto , Idoso , Neoplasias da Mama/patologia , Proliferação de Células/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transdução de Sinais/genética
10.
BMC Cancer ; 18(1): 1234, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30526538

RESUMO

BACKGROUND: Adaptive radiotherapy (ART) has potential benefits in patients with nasopharyngeal cancer (NPC). This retrospective study aimed to identify the factors favoring ART. MATERIALS AND METHODS: Forty NPC patients were retrospectively included in this study. All patients received two-phase, volumetric modulated arc radiotherapy (VMAT) and underwent a second computed tomography (CT) for the phase II ART. We generated phantom, non-ART plans by a hybrid method for comparison with ART plans. A paired t-test was used to evaluate the dose differences between these two plans. A subgroup analysis through a paired t-test was used to evaluate the factors favoring ART. RESULTS: The second CT images were captured at the median 22 fractions. The median total dose of the planning target volume-one (PTV-1) was 72 Gy, and the phase II dose was 16 Gy. The volumes of the ipsilateral parotid gland (23.2 vs. 19.2 ml, p <  0.000), contralateral parotid gland (23.0 vs. 18.4 ml, p <  0.000), clinical target volume-1 (CTV-1, 32.2 vs. 20.9 ml, p <  0.000), and PTV-1 (125.8 vs. 107.3 ml, p <  0.000) all shrunk significantly between these two CT simulation procedures. Among the nearby critical organs, only the ipsilateral parotid gland displayed significant dose reduction by the ART plan (5.3 vs. 6.0 Gy, p = 0.004). Compared to the phantom plan, the ART could significantly improve the PTV-1 target volume coverage of D98 (15.4 vs. 12.3 Gy, p < 0.000). Based on the D98 of PTV-1, the factors of a large initial weight (> 60 kg, p < 0.000), large body mass index (BMI) (> 21.5, p < 0.000), obvious weight loss (> 2.8 kg, p < 0.000), concurrent chemoradiotherapy (p < 0.000), and stages III-IV (p < 0.000) favored the use of ART. CONCLUSIONS: ART could significantly reduce the mean dose to the ipsilateral parotid gland. ART has dosimetrical benefit for patients with a heavy initial weight, large BMI, obvious weight loss, concurrent chemoradiotherapy, and cancer in stages III-IV.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Mar Drugs ; 16(8)2018 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-30060617

RESUMO

Marine sponges are known to produce numerous bioactive secondary metabolites as defense strategies to avoid predation. Manzamine A is a sponge-derived ß-carboline-fused pentacyclic alkaloid with various bioactivities, including recently reported anticancer activity on pancreatic cancer. However, its cytotoxicity and mode of action against other tumors remain unclear. In this study, we exhibit that manzamine A reduced cell proliferation in several colorectal cancer (CRC) cell lines. To further investigate the manzamine A triggered molecular regulation, we analyzed the gene expression with microarray and revealed that pathways including cell cycle, DNA repair, mRNA metabolism, and apoptosis were dysregulated. We verified that manzamine A induced cell cycle arrest at G0/G1 phase via inhibition of cyclin-dependent kinases by p53/p21/p27 and triggered a caspase-dependent apoptotic cell death through mitochondrial membrane potential depletion. Additionally, we performed bioinformatics analysis and demonstrated that manzamine A abolished epithelial⁻mesenchymal transition process. Several mesenchymal transcriptional factors, such as Snail, Slug, and Twist were suppressed and epithelial marker E-cadherin was induced simultaneously in HCT116 cells by manzamine A, leading to the epithelial-like phenotype and suppression of migration. These findings suggest that manzamine A may serve as a starting point for the development of an anticancer drug for the treatment of metastatic CRC.


Assuntos
Antineoplásicos/farmacologia , Carbazóis/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Poríferos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carbazóis/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Avaliação Pré-Clínica de Medicamentos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos
12.
Plant Mol Biol ; 90(1-2): 19-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26482478

RESUMO

Mitogen-activated protein kinase cascades are highly conserved signaling modules downstream of receptors/sensors and play pivotal roles in signaling plant defense against pathogen attack. Extensive studies on Arabidopsis MPK4 have implicated that the MAP kinase is involved in multilayered plant defense pathways. In this study, we identified tobacco NtMPK2 as an ortholog of AtMPK4. Transgenic tobacco overexpressing NtMPK2 markedly enhances resistance to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) virulent and avirulent strains. Transcriptome analysis of NtMPK2-dependent genes shows that possibly the basal resistance system is activated by NtMPK2 overexpression. In addition to NtMPK2-mediated resistance, multiple pathways are involved in response to the avirulent bacteria based on analysis of Pst-responding genes, including SA and ET pathways. Notably, it is possible that biosynthesis of antibacterial compounds is responsible for inhibition of Pst DC3000 avirulent strain when programmed cell death processes in the host. Our results uncover that NtMPK2 positively regulate tobacco defense response to Pst DC3000 and improve our understanding of plant molecular defense mechanism.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nicotiana/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal , Pseudomonas syringae/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequência de Bases , Expressão Gênica , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas Quinases Ativadas por Mitógeno/genética , Dados de Sequência Molecular , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Análise de Sequência de RNA , Transdução de Sinais , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/microbiologia
13.
Plant Biotechnol J ; 14(1): 186-94, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25867543

RESUMO

CRISPR/Cas9 and TALEN are currently the two systems of choice for genome editing. We have studied the efficiency of the TALEN system in rice as well as the nature and inheritability of TALEN-induced mutations and found important features of this technology. The N287C230 TALEN backbone resulted in low mutation rates (0-6.6%), but truncations in its C-terminal domain dramatically increased efficiency to 25%. In most transgenic T0 plants, TALEN produced a single prevalent mutation accompanied by a variety of low-frequency mutations. For each independent T0 plant, the prevalent mutation was present in most tissues within a single tiller as well as in all tillers examined, suggesting that TALEN-induced mutations occurred very early in the development of the shoot apical meristem. Multigenerational analysis showed that TALEN-induced mutations were stably transmitted to the T1 and T2 populations in a normal Mendelian fashion. In our study, the vast majority of TALEN-induced mutations (~81%) affected multiple bases and ~70% of them were deletions. Our results contrast with published reports for the CRISPR/Cas9 system in rice, in which the predominant mutations affected single bases and deletions accounted for only 3.3% of the overall mutations.


Assuntos
Padrões de Herança/genética , Mutagênese/genética , Mutação/genética , Oryza/genética , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Segregação de Cromossomos/genética , Genes de Plantas , Genótipo , Plantas Geneticamente Modificadas
14.
J Org Chem ; 81(22): 10683-10687, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27786466

RESUMO

A novel efficient approach to optically pure bridging chiral calix[4]arenes through a homologous anionic ortho-Fries rearrangement of inherently chiral calix[4]arenes was presented for the first time. As a result, two pairs of N,N'-dimethylformamidyl-substituted bridging chiral p-tert-butylcalix[4]arene enantiomers were facilely obtained. Their absolute configurations were determined through ROESY analysis, ECD comparison, and X-ray crystallographic analysis.

15.
Plant Cell Rep ; 35(7): 1519-33, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26661595

RESUMO

The recently developed CRISPR/Cas9 system is a promising technology for targeted genome editing in a variety of species including plants. However, the first generation systems were designed to target one or two gene loci at a time. We designed a new multiplex CRISPR/Cas9 system that allows the co-expression of six sgRNA modules in one binary vector using a simple (three steps) cloning strategy in Arabidopsis. The transcription of the sgRNA modules is under the control of three different RNA Polymerase III-dependent promoters. We tested the efficiency of the new multiplex system by targeting six of the fourteen PYL families of ABA receptor genes in a single transformation experiment. One line with mutations in all six targeted PYLs was identified from 15 T1 plants. The mutagenesis frequency for the six individual PYL targets in the T1 lines ranged from 13 to 93 %. In the presence of ABA, the transgenic line identified as containing mutations in all six PYL genes produced the highest germination rate in the T2 progeny (37 %). Among these germinated seedlings, half of the analyzed plants (15/30) were homozygous mutants for at least four targeted genes and two plants (6.7 %) contained homozygous mutations in five of the targeted PYLs and the other targeted PYL had biallelic mutations. Homozygous sextuple mutants were identified in the T3 progeny and characterized together with previously described triple and sextuple PYL mutants. We anticipate that the application of this multiplex CRISPR/Cas9 system will strongly facilitate functional analysis of genes pathways and families.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Sistemas CRISPR-Cas , Edição de Genes/métodos , Genoma de Planta/genética , Engenharia Genética/métodos , Vetores Genéticos/genética , Modelos Genéticos , Mutagênese Sítio-Dirigida/métodos , Plantas Geneticamente Modificadas
16.
Appl Microbiol Biotechnol ; 99(5): 2093-104, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25634017

RESUMO

Microbes have long been used in the industry to produce valuable biochemicals. Combinatorial engineering approaches, new strain engineering tools derived from inverse metabolic engineering, have started to attract attention in recent years, including genome shuffling, error-prone DNA polymerase, global transcription machinery engineering (gTME), random knockout/overexpression libraries, ribosome engineering, multiplex automated genome engineering (MAGE), customized optimization of metabolic pathways by combinatorial transcriptional engineering (COMPACTER), and library construction of "tunable intergenic regions" (TIGR). Since combinatorial approaches and high-throughput screening methods are fundamentally interconnected, color/fluorescence-based, growth-based, and biosensor-based high-throughput screening methods have been reviewed. We believe that with the help of metabolic engineering tools and new combinatorial approaches, plus effective high-throughput screening methods, researchers will be able to achieve better results on improving microorganism performance under stress or enhancing biochemical yield.


Assuntos
Biotecnologia/métodos , Ensaios de Triagem em Larga Escala/métodos , Engenharia Metabólica
17.
Front Pharmacol ; 15: 1362484, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384285

RESUMO

Background: Antibody-drug conjugates (ADCs) are a relatively new class of anticancer agents that use monoclonal antibodies to specifically recognize tumour cell surface antigens. However, off-target effects may lead to severe adverse events. This study evaluated the neurotoxicity of ADCs using the FDA Adverse Event Reporting System (FAERS) database. Research design and methods: Data were extracted from the FAERS database for 2004 Q1 to 2022 Q4. We analysed the clinical characteristics of ADC-related neurological adverse events (AEs). We used the reporting odds ratio (ROR) and proportional reporting ratio (PRR) for the disproportionality analysis to evaluate the potential association between AEs and ADCs. Results: A total of 562 cases of neurological AEs were attributed to ADCs. The median age was 65 years old [(Min; Max) = 3; 92]. Neurotoxic signals were detected in patients receiving brentuximab vedotin, enfortumab vedotin, polatuzumab vedotin, trastuzumab emtansine, gemtuzumab ozogamicin, inotuzumab ozogamicin, and trastuzumab deruxtecan. The payloads of brentuximab vedotin, enfortumab vedotin, polatuzumab vedotin, and trastuzumab emtansine were microtubule polymerization inhibitors, which are more likely to develop neurotoxicity. We also found that brentuximab vedotin- and gemtuzumab ozogamicin-related neurological AEs were more likely to result in serious outcomes. The eight most common ADC-related nervous system AE signals were peripheral neuropathy [ROR (95% CI) = 16.98 (14.94-19.30), PRR (95% CI) = 16.0 (14.21-18.09)], cerebral haemorrhage [ROR (95% CI) = 9.45 (7.01-12.73), PRR (95% CI) = 9.32 (6.95-12.50)], peripheral sensory neuropathy [ROR (95% CI) = 47.87 (33.13-69.19), PRR (95% CI) = 47.43 (32.93-68.30)], polyneuropathy [ROR (95% CI) = 26.01 (18.61-36.33), PRR (95% CI) = 25.75 (18.50-35.86)], encephalopathy [ROR (95% CI) = 5.16 (3.32-8.01), PRR (95% CI) = 5.14 (3.32-7.96)], progressive multifocal leukoencephalopathy [ROR (95% CI) = 22.67 (14.05-36.58), PRR (95% CI) = 22.52 (14.01-36.21)], taste disorder [ROR (95% CI) = 26.09 (15.92-42.76), PRR (95% CI) = 25.78 (15.83-42.00)], and guillain barrier syndrome [ROR (95% CI) = 17.844 (10.11-31.51), PRR (95% CI) = 17.79 (10.09-31.35)]. The mortality rate appeared to be relatively high concomitantly with AEs in the central nervous system. Conclusion: ADCs may increase the risk of neurotoxicity in cancer patients, leading to serious mortality. With the widespread application of newly launched ADC drugs, combining the FAERS data with other data sources is crucial for monitoring the neurotoxicity of ADCs. Further studies on the potential mechanisms and preventive measures for ADC-related neurotoxicity are necessary.

18.
J Biomol Struct Dyn ; : 1-9, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258435

RESUMO

The high expression or mutation of SHP2 can induce cancer, so targeting SHP2 has become a new strategy for cancer treatment. In this study, we used the previously reported SHP2 allosteric inhibitor IACS-13909 as a lead drug for structural derivation and modification, and synthesized three SHP2 inhibitors. Among them, 1H-pyrazolo[3,4-b]pyrazine derivative 4b was a highly selective SHP2 allosteric inhibitor, with an IC50 value of 3.2 nM, and its inhibitory activity was 17.75 times than that of the positive control IACS-13909. The cell proliferation experiment detected that compound 4b would markedly inhibit the proliferation of various cancer cells. Interestingly, compound 4b was highly sensitive to KRASG12C-mutant non-small cell lung cancer NCI-H358 cells, with an IC50 value of 0.58 µM and its antiproliferative activity was 4.79 times than that of IACS-13909. Furthermore, the combination therapy of compound 4b and KRASG12C inhibitor sotorasib would play a strong synergistic effect against NCI-H358 cells. The western blot experiment detected that compound 4b markedly downregulated the phosphorylation levels of ERK and AKT in NCI-H358 cells. Molecular docking study predicted that compound 4b bound to the allosteric site of SHP2 and formed H-bond interactions with key residues Thr108, Glu110, Arg111, and Phe113. In summary, this study aims to provide new ideas for the development of SHP2 allosteric inhibitors for the treatment of KRASG12C mutant non-small cell lung cancer.Communicated by Ramaswamy H. Sarma.

19.
Plants (Basel) ; 13(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38475518

RESUMO

Botrytis cinerea, the causative agent of gray mold disease (GMD), invades plants to obtain nutrients and disseminates through airborne conidia in nature. Bacillus amyloliquefaciens strain GD4a, a beneficial bacterium isolated from switchgrass, shows great potential in managing GMD in plants. However, the precise mechanism by which GD4a confers benefits to plants remains elusive. In this study, an A. thaliana-B. cinerea-B. amyloliquefaciens multiple-scale interaction model was used to explore how beneficial bacteria play essential roles in plant growth promotion, plant pathogen suppression, and plant immunity boosting. Arabidopsis Col-0 wild-type plants served as the testing ground to assess GD4a's efficacy. Additionally, bacterial enzyme activity and targeted metabolite tests were conducted to validate GD4a's potential for enhancing plant growth and suppressing plant pathogens and diseases. GD4a was subjected to co-incubation with various bacterial, fungal, and oomycete pathogens to evaluate its antagonistic effectiveness in vitro. In vivo pathogen inoculation assays were also carried out to investigate GD4a's role in regulating host plant immunity. Bacterial extracellular exudate (BEE) was extracted, purified, and subjected to untargeted metabolomics analysis. Benzocaine (BEN) from the untargeted metabolomics analysis was selected for further study of its function and related mechanisms in enhancing plant immunity through plant mutant analysis and qRT-PCR analysis. Finally, a comprehensive model was formulated to summarize the potential benefits of applying GD4a in agricultural systems. Our study demonstrates the efficacy of GD4a, isolated from switchgrass, in enhancing plant growth, suppressing plant pathogens and diseases, and bolstering host plant immunity. Importantly, GD4a produces a functional bacterial extracellular exudate (BEE) that significantly disrupts the pathogenicity of B. cinerea by inhibiting fungal conidium germination and hypha formation. Additionally, our study identifies benzocaine (BEN) as a novel small molecule that triggers basal defense, ISR, and SAR responses in Arabidopsis plants. Bacillus amyloliquefaciens strain GD4a can effectively promote plant growth, suppress plant disease, and boost plant immunity through functional BEE production and diverse gene expression.

20.
Int J Biol Macromol ; 254(Pt 2): 127845, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37935292

RESUMO

Targeting SHP2 has become a potential cancer treatment strategy. In this study, ellagic acid was first reported as a competitive inhibitor of SHP2, with an IC50 value of 0.69 ± 0.07 µM, and its inhibitory potency was 34.86 times higher that of the positive control NSC87877. Ellagic acid also had high inhibitory activity on the SHP2-E76K and SHP2-E76A mutants, with the IC50 values of 1.55 ± 0.17 µM and 0.39 ± 0.05 µM, respectively. Besides, the IC50 values of ellagic acid on homologous proteins SHP1, PTP1B, and TCPTP were 0.93 ± 0.08 µM, 2.04 ± 0.28 µM, and 11.79 ± 0.83 µM, with selectivity of 1.35, 2.96, and 17.09 times, respectively. The CCK8 proliferation experiment exhibited that ellagic acid would inhibit the proliferation of various cancer cells. It was worth noting that the combination of ellagic acid and KRASG12C inhibitor AMG510 would produce a strong synergistic effect in inhibiting NCI-H358 cells. Western blot experiment exhibited that ellagic acid would downregulate the phosphorylation levels of Erk and Akt in NCI-H358 and MDA-MB-468 cells. Molecular docking and molecular dynamics studies revealed the binding information between SHP2 and ellagic acid. In summary, this study provides new ideas for the development of SHP2 inhibitors.


Assuntos
Ácido Elágico , Neoplasias , Humanos , Ácido Elágico/farmacologia , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Inibidores Enzimáticos/química , Fosforilação
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