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1.
Nat Prod Res ; : 1-10, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956986

RESUMO

Red wine is rich in anthocyanins and procyanidins which possess multiple health-promoting properties. However, the synergistically anticancer effects of them on gastric cancer cells still undefined. The results showed that combination of malvidin-3-O-(6-O-coumaroyl)-glucoside-5-O-glucoside (M35GC) and procyanidin C1 could effectively inhibited the viability of MKN-28 cells with the lowest IC50 value. Mechanistically, M35GC and procyanidin C1 significantly induced cell apoptosis by reducing the ratio of Bcl-2/Bax, blocked cell cycle in G0/G1 phase by decreasing CDK4 protein and decreased glucose consumption and lactate production during aerobic glycolysis through suppressing the expression of HK2 protein in MKN-28 cells. In conclusion, induction of cell apoptosis and cell cycle arrest, as well as the inhibition of HK2 protein that participates in the glycolytic pathway and the suppression of aerobic glycolysis by M35GC and procyanidin C1 contributed to the anti-cancer effects in gastric cancer.

2.
NPJ Breast Cancer ; 10(1): 35, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734703

RESUMO

BRCA1 plays a suppressive role in breast tumorigenesis. Ubiquitin-dependent degradation is a common mechanism that regulates BRCA1 protein stability, and several ubiquitin ligases involved have been identified. However, the deubiquitinating enzyme for BRCA1 remains less defined. Here, we report that the deubiquitinase USP4 interacts with, deubiquitinates and stabilizes BRCA1, maintaining the protein level of BRCA1. USP4 knockdown results in a decreased BRCA1 protein level, impairment in homologous recombination mediated double-stranded break repair, and increased genome instability, and confers resistance to DNA damage-inducing agents and PARP inhibitors. Ectopic expression of USP4 stabilizes BRCA1 and reverse the effects caused by USP4 knockdown. Moreover, USP4 is low expressed in human breast cancer tissues and its low expression correlates with poorer survival of patients. Furthermore, we identified several loss-of-function mutations of USP4 in human gynecological cancers, the catalytic activity of which or their interaction with BRCA1 is disrupted. Together, we reveal that USP4 is a deubiquitinase for BRCA1. USP4 positively regulates the stability and function of BRCA1 through de-ubiquitination, and plays important role in the suppression of breast cancer.

3.
Eur J Pharmacol ; 959: 176084, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37806540

RESUMO

Vascular calcification (VC) is associated with increased morbidity and mortality, especially among people with type 2 diabetes mellitus (T2DM). The pathogenesis of vascular calcification is incompletely understood, and until now, there have been no effective therapeutics for vascular calcification. The L-type calcium ion channel in the cell membrane is vital for Ca2+ influx. The effect of L-type calcium ion channels on autophagy remains to be elucidated. Here, the natural compound thonningianin A (TA) was found to ameliorate vascular calcification in T2DM via the activation of L-type calcium ion channels. The results showed that TA had a concentration-dependent ability to decrease the transcriptional and translational expression of the calcification-related proteins runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP2) and osteopontin (OPN) (P < 0.01) via ATG7-dependent autophagy in ß-glycerophosphate (ß-GP)- and high glucose (HG)-stimulated primary mouse aortic smooth muscle cells (MASMCs) and alleviate aortic vascular calcification in VitD3-stimulated T2DM mice. However, nifedipine, an inhibitor of L-type calcium ion channels, reversed TA-induced autophagy and Ca2+ influx in MASMCs. Molecular docking analysis revealed that TA was located in the hydrophobic pocket of Cav1.2 α1C and was mainly composed of the residues Ile, Phe, Ala and Met, which confirmed the efficacy of TA in targeting the L-type calcium channel of Cav1.2 on the cell membrane. Moreover, in an in vivo model of vascular calcification in T2DM mice, nifedipine reversed the protective effects of TA on aortic calcification and the expression of the calcification-related proteins RUNX2, BMP2 and OPN (P < 0.01). Collectively, the present results reveal that the activation of cell membrane L-type calcium ion channels can induce autophagy and ameliorate vascular calcification in T2DM. Thonningianin A (TA) can target and act as a potent activator of L-type calcium ion channels. Thus, this research revealed a novel mechanism for autophagy induction via L-type calcium ion channels and provided a potential therapeutic for vascular calcification in T2DM.


Assuntos
Diabetes Mellitus Tipo 2 , Calcificação Vascular , Humanos , Camundongos , Animais , Canais de Cálcio Tipo L/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Músculo Liso Vascular , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Simulação de Acoplamento Molecular , Nifedipino/farmacologia , Nifedipino/uso terapêutico , Calcificação Vascular/etiologia , Calcificação Vascular/induzido quimicamente , Autofagia , Miócitos de Músculo Liso , Cálcio/metabolismo , Células Cultivadas
4.
Drug Resist Updat ; 69: 100975, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37207473

RESUMO

AIMS: Vessel co-option is responsible for tumor resistance to antiangiogenic therapies (AATs) in patients with colorectal cancer liver metastasis (CRCLM). However, the mechanisms underlying vessel co-option remain largely unknown. Herein, we investigated the roles of a novel lncRNA SYTL5-OT4 and Alanine-Serine-Cysteine Transporter 2 (ASCT2) in vessel co-option-mediated AAT resistance. METHODS: SYTL5-OT4 was identified by RNA-sequencing and verified by RT-qPCR and RNA fluorescence in situ hybridization assays. The effects of SYTL5-OT4 and ASCT2 on tumor cells were investigated by gain- and loss-of-function experiments, and those of SYTL5-OT4 on ASCT2 expression were analyzed by RNA immunoprecipitation and co-immunoprecipitation assays. The roles of SYTL5-OT4 and ASCT2 in vessel co-option were detected by histological, immunohistochemical, and immunofluorescence analyses. RESULTS: The expression of SYTL5-OT4 and ASCT2 was higher in patients with AAT-resistant CRCLM. SYTL5-OT4 enhanced the expression of ASCT2 by inhibiting its autophagic degradation. SYTL5-OT4 and ASCT2 promoted vessel co-option by increasing the proliferation and epithelial-mesenchymal transition of tumor cells. Combination therapy of ASCT2 inhibitor and antiangiogenic agents overcame vessel co-option-mediated AAT resistance in CRCLM. CONCLUSION: This study highlights the crucial roles of lncRNA and glutamine metabolism in vessel co-option and provides a potential therapeutic strategy for patients with AAT-resistant CRCLM.


Assuntos
Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Alanina , Proteínas de Transporte , Linhagem Celular Tumoral , Cisteína , Hibridização in Situ Fluorescente , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Proteínas de Membrana , Proteínas de Membrana Transportadoras , RNA Longo não Codificante/genética , Serina
5.
J Immunol ; 210(5): 681-695, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602827

RESUMO

Hepatocellular carcinoma (HCC) has the third highest cancer-related mortality rate globally. The immunosuppressive microenvironment of HCC limits effective treatment options. HCC cells and associated microenvironmental factors suppress NK and T cell infiltration and cytotoxic activities. The abnormal number or function of NK and T cells leads to a lack of immune surveillance. Recently, immunotherapy targeting PD-1 and PD-L1 has been shown to activate functionally exhausted cytotoxic immune cells in some solid tumors. However, the response rate and therapeutic efficacy against solid tumors with little lymphocyte infiltration are limited, especially for HCC. Therefore, new targets and therapeutics that induce tumor cell apoptosis and overcome the problem of depletion of immune cells, thereby inhibiting the immune escape of HCC cells, are urgently required. Butaselen (2-bis[2-(1,2-benzisothiazol-2(2H)-ketone)]butane), an organic molecule containing selenium, is a new type of thioredoxin reductase inhibitor. In this study, we found that butaselen promoted NK and T cell activity and infiltration in the tumor microenvironment in HCC-bearing mice by enhancing the expression of CXCR3, NKG2D, and their respective ligands. When used alone, it can significantly inhibit tumor growth and exert a synergistic effect in combination with PD-1 blockade. We suggested the role of the thioredoxin reductase system in the regulation of the tumor immunosuppressive microenvironment and developed a new effective therapeutic molecule for HCC, revealing the mechanism of butaselen in inhibiting tumor cell immune escape.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Linfócitos T CD8-Positivos , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Tiorredoxina Dissulfeto Redutase/farmacologia , Microambiente Tumoral , Células Matadoras Naturais , Humanos
6.
ACS Nano ; 15(6): 10393-10405, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34008953

RESUMO

A general and quantitative method to characterize molecular transport in polymers with good temporal and high spatial resolution, in complex environments, is an important need of the pharmaceutical, textile, and food and beverage packaging industries, and of general interest to the polymer science community. Here we show how the amplified infrared (IR) absorbance sensitivity provided by plasmonic nanoantenna-based surface enhanced infrared absorption (SEIRA) provides such a method. SEIRA enhances infrared (IR) absorbances primarily within 50 nm of the nanoantennas, enabling localized quantitative detection of even trace quantities of analytes and diffusion measurements in even thin polymer films. Relative to a commercial attenuated total internal reflection (ATR) system, the limit of detection is enhanced at least 13-fold, and as is important for measuring diffusion, the detection volume is about 15 times thinner. Via this approach, the diffusion coefficient and solubility of specific molecules, including l-ascorbic acid (vitamin C), ethanol, various sugars, and water, in both simple and complex mixtures (e.g., beer and a cola soda), were determined in poly(methyl methacrylate), high density polyethylene (HDPE)-based, and polypropylene-based polyolefin films as thin as 250 nm.


Assuntos
Polímeros , Água , Difusão , Solubilidade
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