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1.
Chem Sci ; 13(43): 12851-12857, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36519035

RESUMO

The amination and alkenylation of the C(sp3)-H bond at the N-α position of secondary benzamides were both realized in this work by using N-hydroxyphthalimide (NHPI) imidate esters as substrates under a dual catalysis involving a photoredox catalyst and hydrogen atom transfer (HAT) catalyst. The developed methods significantly extended the scope of applications of the N-α position C(sp3)-H bond functionalization with regard to secondary N-alkylamides. More importantly, new reaction models in photoredox catalysis have been established. Based on corresponding experiments and density functional theory (DFT) calculations on the critical reaction steps combined with information reported previously, we proposed a synergistic photo- and organocatalytic reaction process for the C(sp3)-H bond functionalization and also clarified the occurrence of a chain process in the reaction pathway.

2.
Chem Commun (Camb) ; 58(71): 9954-9957, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35983765

RESUMO

The site selective C(sp2)-H bond functionalization of olefins has been achieved through a visible-light-induced photoredox-quinuclidine dual catalysis upon merging the quinuclidinium radical cation addition to alkene strategy and the distal heteroaryl ipso-migration strategy. This synthetic protocol features a simple operation with readily available starting materials in good step-economy to access alkenylheteroaromatic products in moderate to good yields under mild conditions. A plausible cascade catalytic reaction mechanism is also proposed.

3.
Chem Sci ; 13(5): 1478-1483, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35222932

RESUMO

A strategy for overcoming the limitation of the Morita-Baylis-Hillman (MBH) reaction, which is only applicable to electron-deficient olefins, has been achieved via visible-light induced photoredox catalysis in this report. A series of non-electron-deficient olefins underwent the MBH reaction smoothly via a novel photoredox-quinuclidine dual catalysis. The in situ formed key ß-quinuclidinium radical intermediates, derived from the addition of olefins with quinuclidinium radical cations, are used to enable the MBH reaction of non-electron-deficient olefins. On the basis of previous reports, a plausible mechanism is suggested. Mechanistic studies, such as radical probe experiments and density functional theory (DFT) calculations, were also conducted to support our proposed reaction pathways.

4.
World J Gastroenterol ; 25(38): 5814-5825, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31636474

RESUMO

BACKGROUND: Wnt1-inducible signaling pathway protein 1 (WISP1) is upregulated in several types of human cancer, and has been implicated in cancer progression. However, its clinical implications in gastric cancer (GC) remain unclear. AIM: To explore the expression pattern and clinical significance of WISP1 in GC. METHODS: Public data portals, including Oncomine, The Cancer Genome Atlas database, Coexpedia, and Kaplan-Meier plotter, were analyzed for the expression and clinical significance of WISP1 mRNA levels in GC. One hundred and fifty patients who underwent surgery for GC between February 2010 and October 2012 at the Affiliated Hospital of Jiangnan University were selected for validation study. WISP1 levels were measured at both the mRNA and protein levels by RT-qPCR, Western blot analysis, and immunohistochemistry (IHC). In addition, the in situ expression of WISP1 in the GC tissues was determined by IHC, and the patients were accordingly classified into high- and low-expression groups. The correlation of WISP1 expression status with patient prognosis was then determined by univariate and multivariate Cox regression analyses. WISP1 was knocked down by RNA interference. The 50% inhibitory concentration of oxaliplatin was detected by CellTiter-Blue assay. RESULTS: WISP1 levels at both the mRNA and protein levels were remarkably upregulated in GC tissues compared to normal tissues. Moreover, IHC revealed that WISP1 expression was associated with T stage and chemotherapy outcome, but not with lymph node metastasis, age, gender, histological grade, or histological type. GC patients with high WISP1 expression showed a poor overall survival. Multivariate survival analysis indicated that WISP1 was an important prognostic factor for GC patients. Mechanistically, knock-down of WISP1 expression enhanced sensitivity to oxaliplatin by reducing DNA repair and enhancing DNA damage. CONCLUSION: Significantly upregulated WISP1 expression is associated with cancer progression, chemotherapy outcome, and prognosis in GC. Mechanistically, knock-down of WISP1 expression enhances oxaliplatin sensitivity by reducing DNA repair and enhancing DNA damage. WISP1 may be a potential therapeutic target for GC treatment or a potential biomarker for diagnosis and prognosis.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Proteínas de Sinalização Intercelular CCN/metabolismo , Reparo do DNA , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias Gástricas/terapia , Antineoplásicos/uso terapêutico , Proteínas de Sinalização Intercelular CCN/genética , Linhagem Celular Tumoral , Quimioterapia Adjuvante/métodos , Feminino , Gastrectomia , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Concentração Inibidora 50 , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Prognóstico , Proteínas Proto-Oncogênicas/genética , Estômago/patologia , Estômago/cirurgia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Resultado do Tratamento , Regulação para Cima
5.
Front Oncol ; 9: 776, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497531

RESUMO

Colorectal cancer (CRC) is one of the most prevalent digestive tumors in China. Recent studies indicate that long intergenic non-coding RNAs (lincRNAs) play a crucial role in predicting survival for CRC patients. However, the novel lincRNA, LINC00957, is largely unclear in CRC. The purpose of the current study was to determine LINC00957 expression, assess its the clinical significance and explore the potential mechanism in CRC. The qRT-PCR was used to quantify the expression levels of LINC00957 in tissues and cell lines. Our research revealed that LINC00957 was significantly higher expression in CRC. In addition, the LINC00957 expression was associated with TNM stage and chemotherapy outcome, but age, gender, tumor size, histological grade, primary tumor location. CRC patients with high LINC00957 expression level showed poor overall survival (P = 0.002). Multivariate survival analysis indicated that LINC00957 was a prognostic factor for CRC patients (P = 0.010). Mechanically, inhibition of LINC00957 expression reversed 5-FU resistance by down-regulating P-gP. In summary, our study indicated that this novel lncRNA expression signature might be a useful biomarker of the prognosis and therapeutic target for CRC patients.

6.
World J Clin Cases ; 7(15): 1954-1963, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31423427

RESUMO

BACKGROUND: Vestigial like family member 3 (VGLL3) is associated with the prognosis of epithelial ovarian cancer and soft tissue sarcoma, but its role in gastric cancer (GC) is unclear. AIM: To explore the expression pattern and clinical significance of VGLL3 in GC. METHODS: Integrative analysis was performed on the GC transcriptome profiles and survival information deposited in the ONCOMINE, GEPIA, and ONCOLNC databases. The expression levels of VGLL3 mRNA and protein were analyzed in the freshly resected tumor and normal gastric tissues from GC patients by quantitative RT-PCR and Western blot, respectively. In addition, the in situ expression of VGLL3 in the GC tissues was determined by immunohistochemistry (IHC), and the patients were accordingly classified into the high and low expression groups. The correlation of VGLL3 expression status with patient prognosis was then determined by univariate and multivariate Cox regression analyses. RESULTS: Analysis of the ONCOMINE and GEPIA databases showed that VGLL3 was significantly up-regulated in GC tissues (P = 0.003), and associated with the tumor TNM stage (P = 0.0163). The high VGLL3 expression group had a significantly worse prognosis compared to the low expression group, as per both GEPIA (P = 0.0057) and ONCOLNC (P = 0.01). The bioinformatics results were validated by the significantly higher VGLL3 mRNA and protein levels in the GC tissues compared to the adjacent normal tissues (P < 0.001) in a cohort of 30 GC patients. Furthermore, high in situ expression of VGLL3 protein was associated with more advanced N and TNM stages and HER2 mutation (P < 0.05) in a cohort of 172 patients. Kaplan-Meier analysis showed that the high VGLL3 expression group had a worse prognosis compared to the low expression group (P = 0.019). Multivariate analysis showed that VGLL3 expression status was an independent risk factor for prognosis. In addition, the prognostic risk model nomogram showed that VGLL3 was the most important indicator, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.613 for 3-year survival and 0.706 for 5-year survival. Finally, the protein interaction network analysis revealed that VGLL3 is likely involved in the Hippo signaling pathway. CONCLUSION: VGLL3 is overexpressed in GC tissues and associated with a poor prognosis, indicating its potential as a novel prognosis biomarker and therapeutic target for GC.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(4): 878-82, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19626863

RESUMO

The emission spectra of pure oxygen in dielectric barrier discharge at atmospheric pressure were observed. Comparison between experimental and fitting spectra of oxygen A band (b 1Sigmag(+) --> X 3Sigmag(-)) (0, 0) was used to determine the gas temperature, and the electronic temperature was calculated from O I lines. The causation of oxygen A band in atmospheric dielectric barrier discharge was discussed by means of analysis of producing and quenching approaches. The result showed that the electronic temperature, (11,800+/-400) K, was much higher than the gas temperature, (650+/-20) K. The emission from a 1Deltag or A 3Sigmau(+) was not been observed, but atmospheric band with its resoluble rotational structure was measured.

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