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1.
Cancer Sci ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623968

RESUMO

Enhancing sensitivity to sorafenib can significantly extend the duration of resistance to it, offering substantial benefits for treating patients with hepatocellular carcinoma (HCC). However, the role of ferroptosis in influencing sorafenib sensitivity within HCC remains pivotal. The enhancer of zeste homolog 2 (EZH2) plays a significant role in promoting malignant progression in HCC, yet the relationship between ferroptosis, sorafenib sensitivity, and EZH2 is not entirely clear. Bioinformatic analysis indicates elevated EZH2 expression in HCC, predicting an unfavorable prognosis. Overexpressing EZH2 can drive HCC cell proliferation while simultaneously reducing ferroptosis. Further analysis reveals that EZH2 amplifies the modification of H3K27 me3, thereby influencing TFR2 expression. This results in decreased RNA polymerase II binding within the TFR2 promoter region, leading to reduced TFR2 expression. Knocking down EZH2 amplifies sorafenib sensitivity in HCC cells. In sorafenib-resistant HepG2(HepG2-SR) cells, the expression of EZH2 is increased. Moreover, combining tazemetostat-an EZH2 inhibitor-with sorafenib demonstrates significant synergistic ferroptosis-promoting effects in HepG2-SR cells. In conclusion, our study illustrates how EZH2 epigenetically regulates TFR2 expression through H3K27 me3, thereby suppressing ferroptosis. The combination of the tazemetostat with sorafenib exhibits superior synergistic effects in anticancer therapy and sensitizes the HepG2-SR cells to sorafenib, shedding new light on delaying and ameliorating sorafenib resistance.

2.
Chemosphere ; 341: 140093, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37678595

RESUMO

Di(2-ethylhexyl) phthalate (DEHP) has been widely detected in soil, water, and sediment as a priority control pollutant. Immobilized microorganism technology is gradually mature and applied in production. Biochar prepared from agricultural wastes is an excellent immobilized carrier because of its porous structure and abundant functional groups. Environmental acidification was caused by degrading bacteria Arthrobacter sp. JQ-1 (JQ-1) respiration and acidic metabolites during DEHP degradation, which affected the passage life of microorganisms and the removal efficiency of DEHP. The mechanism of DEHP degradation by the combined action of JQ-1 and corn straw biochar (BC) at 600 °C was investigated, and bacterial viability, microenvironmental changes, and kinetic tests were performed in this research. Compared with biodegradation group alone, the degradation rate of DEHP in 1% biochar unloaded and loaded with JQ-1 increased by 18.3% and 30.9%, and its half-life decreased to 23.90 h and 11.95h, a reduction of 31.37 h. The percentage of detected living JQ-1 increased as biochar content increased when loading capacity was less than 1%. In which, (JQ-1-BC2) group was 4.1% higher than (JQ-1-BC1) group. Biochar has the ability to neutralize acidifying environmental pH due to its alkaline functional groups, including lactone group, -OH, -COO-. 1% biochar loaded with JQ-1 increased the pH of the microenvironment by 0.57 and alkaline phosphatase (AKP) activity by 0.0063 U·mL-1, which promoted the reduction of PA. Study suggested that biochar loaded with JQ-1 could simultaneously adsorb and degrade DEHP during the process of DEHP removal. Biochar could be used as a biological stimulant to increase abundance and metabolism, enhance the utilization of DEHP by JQ-1. Biochar (1% (w/v)) loaded with JQ-1 as DEHP removal material showed good performance. Biochar not only as an immobilized carrier, but also as a biostimulant, providing an effective strategy for the collaborative remediation of PAEs contaminated.


Assuntos
Arthrobacter , Dietilexilftalato , Ácidos Ftálicos , Poluentes do Solo , Dietilexilftalato/metabolismo , Arthrobacter/metabolismo , Viabilidade Microbiana , Poluentes do Solo/química , Biodegradação Ambiental , Solo/química
3.
Genet Mol Biol ; 46(2): e20220323, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37335919

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of liver malignancy with high incidence and poor prognosis. Transmembrane protein 147 (TMEM147) has been implicated in the development of colon cancer. However, the role of TMEM147 in HCC remains unclear. In this study, data of 371 HCC tissues, 50 adjacent nontumor tissues, and 110 normal liver tissues were retrieved from the TCGA and GTEx databases. TMEM147 expression was found to be increased in HCC tissues. High expression of TMEM147 was related to poor prognosis, and TMEM147 was confirmed to be an independent prognostic factor for HCC patients. A receiver operating characteristics (ROC) analysis was performed and showed that the diagnostic efficacy of TMEM147 was significantly higher than that of AFP (0.908 versus 0.746, p < 0.001). Furthermore, TMEM147 promoted tumor immune infiltration, and macrophages were the immune cells that predominantly expressed TMEM147 in HCC. Further analysis revealed that TMEM147 mainly impacted the ribosome pathway, and CTCF, MLLT1, TGIF2, ZNF146, and ZNF580 were predicted to be the upstream transcription factors for TMEM147 in HCC. These results suggest that TMEM147 serves as a promising biomarker for diagnosis and prognosis and may potentially become a therapeutic target for HCC.

4.
Nat Prod Res ; : 1-7, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36762720

RESUMO

Crotonyanes A (1) and B (2), two new cembranoids were isolated from the leaves and twigs of Croton yanhuii Y. T. Chang. Their structures were elucidated by extensive spectroscopic analyses and quantum chemical calculations. Bioassays verified that compound 1 exhibited an inhibitory effect on nitric oxide (NO) production in RAW 264.7 cells, with an IC50 value of 30.6 ± 4.3 µM.

5.
Inflamm Bowel Dis ; 29(1): 103-115, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35907203

RESUMO

BACKGROUND: Crohn's disease (CD) is an incurable chronic intestinal inflammatory disease with no recognized cause. It has been reported that the mechanosensitive ion channel PIEZO1 initiates proinflammatory responses. However, little is known about the role of PIEZO1 in CD. METHODS: Ileum biopsies were obtained from 30 patients with CD and 15 healthy volunteers. Clinical data were collected to determine the relationship between CD and PIEZO1. First, HT29 cells were incubated with Yoda1 and GsMTx4 (Grammostola spatulata mechanotoxin 4) to activate and inhibit PIEZO1, respectively. Second, PIEZO1 knockdown was performed using small interfering RNA. Third, calcium imaging, flow cytometry, and immunofluorescence were used to detect intracellular calcium and mitochondrial function. Last, real-time quantitative polymerase chain reaction, immunoblotting, and enzyme-linked immunosorbent assay were used to quantify PIEZO1, proinflammatory cytokines, and NLRP3 (NOD-like receptor 3)-related compounds. RESULTS: PIEZO1 was highly expressed in the ileum of patients with CD and correlated positively with the Crohn's Disease Activity Index, platelet count, and hematocrit and fecal calprotectin levels. In HT29 cells, Yoda1 triggered calcium influx, which was inhibited by GsMTx4 treatment and small interfering RNA-mediated PIEZO1 knockdown. Increased calcium concentrations resulted in increased reactive oxygen species accumulation and decreased mitochondrial membrane potential, whereas decreased calcium concentrations caused by GsMTx4 and PIEZO1 knockdown had the opposite effect. Mechanistically, molecules in the NLRP3 pathway were activated in patients with CD and HT29 cells were stimulated by lipopolysaccharide; these effects were reversed by the knockdown of PIEZO1. Finally, PIEZO1 and NLRP3 knockdown decreased proinflammatory cytokine levels in HT29 cells. CONCLUSIONS: PIEZO1 in intestinal epithelial cells caused calcium influx, which resulted in mitochondrial dysfunction and activated the NLRP3 inflammasome, mediating intestinal inflammation.


PIEZO1 was highly expressed in patients with active Crohn's disease. Its expression was significantly increased in the ileum and was associated with intestinal inflammation. In intestinal epithelial cells, PIEZO1 triggered calcium influx, resulting in mitochondrial dysfunction, and activated the NLRP3 inflammasome, thereby mediating intestinal inflammation.


Assuntos
Doença de Crohn , Humanos , Cálcio/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Inflamação , Células Epiteliais/metabolismo , Citocinas/metabolismo , RNA Interferente Pequeno/genética
6.
Adv Sci (Weinh) ; 9(3): e2103493, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34802197

RESUMO

The investigation of novel growth mechanisms for electrodes and the understanding of their in situ energy storage mechanisms remains major challenges in rechargeable lithium-ion batteries. Herein, a novel mechanism for the growth of high-purity diversified Li3 VO4 nanostructures (including hollow nanospheres, uniform nanoflowers, dispersed hollow nanocubes, and ultrafine nanowires) has been developed via a microwave irradiation strategy. In situ synchrotron X-ray diffraction and in situ transmission electron microscope observations are applied to gain deep insight into the intermediate Li3+ x VO4 and Li3+ y VO4 phases during the lithiation/delithiation mechanism. The first-principle calculations show that lithium ions migrate into the nanosphere wall rapidly along the (100) plane. Furthermore, the Li3 VO4 hollow nanospheres deliver an outstanding reversible capacity (299.6 mAh g-1 after 100 cycles) and excellent cycling stability (a capacity retention of 99.0% after 500 cycles) at 200 mA g-1 . The unique nanostructure offers a high specific surface area and short diffusion path, leading to fast thermal/kinetic reaction behavior, and preventing undesirable volume expansion during long-term cycling.

7.
Exp Ther Med ; 22(1): 735, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34055052

RESUMO

Oleanolic acid (OA) is a natural compound that can be found in a number of edible and medicinal plants and confers diverse biological actions. However, the direct target of OA in human tumor cells remains poorly understood, preventing its application in clinical and health settings. A previous study revealed that overexpression of caveolin-1 in human leukemia HL-60 cells can increase its sensitivity to OA. The present study aimed to investigate the effects of OA on the doxorubicin-resistant human breast cancer MCF-7 cell line (MCF-7/DOX), harringtonine-resistant human leukemia HL-60 cells (HL-60/HAR) and their corresponding parental cell lines. Western blotting was performed to measure protein expression levels, whilst Cell Counting Kit-8 (CCK-8) assays, cell cycle analysis (by flow cytometry) and apoptosis assays (with Annexin V/PI staining) were used to assess drug sensitivity. CCK-8 assay results suggested that MCF-7/DOX cells, which overexpress the caveolin-1 protein, have similar OA susceptibility to their parent line. In addition, sensitivity of MCF-7/DOX cells to OA was not augmented by knocking down caveolin-1 using RNA interference. HL-60/HAR cells exhibited a four-fold increased sensitivity to OA compared with that in their parental HL-60 cells according to CCK-8 assay. Both of the resistant cell lines exhibited higher numbers of cells at G1 phase arrest compared with those in their parent lines, as measured via flow cytometry. Treatment of both MCF-7 cell lines with 100 µM OA for 48 h induced apoptosis, with increased effects observed in resistant cells. However, no PARP-1 or caspase-3 cleavage was observed, with some positive Annexin V staining found after HL-60/HAR cells were treated with OA, suggesting that cell death occurred via non-classical apoptosis or through other cell death pathways. It was found that OA was not a substrate of ATP-binding cassette subfamily B member 1 (ABCB1) in drug-resistant cells, as indicated by the accumulation of rhodamine 123 assessed using flow cytometry. However, protein expression of ABCB1 in both of the resistant cell lines was significantly decreased after treatment with OA in a concentration-dependent manner. Collectively, these results suggest that OA could reduce ABCB1 protein expression and induce G1 phase arrest in multidrug-resistant cancer cells. These findings highlight the potential of OA for cancer therapy.

8.
Oncol Rep ; 32(1): 293-301, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24842472

RESUMO

Our previous study found that caveolin-1 (CAV-1) protein expression is upregulated during oleanolic acid (OA)-induced inhibition of proliferation and promotion of apoptosis in HL-60 cells. CAV-1 is the main structural protein component of caveolae, playing important roles in tumorigenesis and tumor development. It has been shown that cav-1 expression is lower in leukemia cancer cell lines SUP-B15, HL-60, THP-1 and K562 and in chronic lymphocytic leukemia primary (CLP) cells when compared with normal white blood cells, with the lowest cav-1 expression level found in HL-60 cells. To study the effects of cav-1 in HL-60 cells and the effects of cav-1 overexpression on OA drug efficacy, cav-1 was overexpressed in HL-60 cells using lentiviral-mediated transfection combined with OA treatment. The results showed that cav-1 overexpression inhibited HL-60 cell proliferation, promoted apoptosis, arrested the cell cycle in the G1 phase and inhibited activation of the PI3K/AKT/mTOR signaling pathway. Overexpression of CAV-1 also increased HL-60 cell sensitivity to OA. To further verify whether OA affects HL-60 cells via the activation of downstream signaling pathways by CAV-1, cav-1 gene expression was silenced using RNAi, and the cells were treated with OA to examine its efficacy. The results showed that after cav-1 silencing, OA had little effect on cell activity, apoptosis, the cell cycle and phosphorylation of HL-60 cells. This study is the first to show that CAV-1 plays a crucial role in the effects of OA on HL-60 cells.


Assuntos
Caveolina 1/genética , Caveolina 1/metabolismo , Leucemia/patologia , Ácido Oleanólico/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Células HL-60 , Humanos , Leucemia/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos
9.
Sheng Wu Gong Cheng Xue Bao ; 30(9): 1464-72, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25720161

RESUMO

Three long-chain polyunsaturated fatty acids, docosahexaenoic acid (DHA, 22:6n-3), eicosapentaenoic acid (EPA, 20:5n-3) and arachidonic acid (ARA, 20:4n-6), are the most biologically active polyunsaturated fatty acids in the body. They are important in developing and maintaining the brain function, and in preventing and treating many diseases such as cardiovascular disease, inflammation and cancer. Although mammals can biosynthesize these long-chain polyunsaturated fatty acids, the efficiency is very low and dietary intake is needed to meet the requirement. In this study, a multiple-genes expression vector carrying mammalian A6/A5 fatty acid desaturases and multiple-genes expression vector carrying mammalian Δ6/Δ5 fatty acid desaturases and Δ6/Δ5 fatty acid elongases coding genes was used to transfect HEK293T cells, then the overexpression of the target genes was detected. GC-MS analysis shows that the biosynthesis efficiency and level of DHA, EPA and ARA were significantly increased in cells transfected with the multiple-genes expression vector. Particularly, DHA level in these cells was 2.5 times higher than in the control cells. This study indicates mammal possess a certain mechanism for suppression of high level of biosynthesis of long chain polyunsaturated fatty acids, and the overexpression of Δ6/Δ5 fatty acid desaturases and Δ6/Δ5 fatty acid elongases broke this suppression mechanism so that the level of DHA, EPA and ARA was significantly increased. This study also provides a basis for potential applications of this gene construct in transgenic animal to produce high level of these long-chain polyunsaturated fatty acid.


Assuntos
Ácido Graxo Sintases/metabolismo , Ácidos Graxos Insaturados/biossíntese , Acetiltransferases/genética , Acetiltransferases/metabolismo , Ácido Araquidônico/biossíntese , Ácidos Docosa-Hexaenoicos/biossíntese , Ácido Eicosapentaenoico/biossíntese , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Elongases de Ácidos Graxos , Ácido Graxo Sintases/genética , Vetores Genéticos , Células HEK293 , Humanos , Transfecção
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(4): 905-10, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23998583

RESUMO

This study was purposed to explore the effect of lentivirus-mediated CAV1 overexpression on proliferation and apoptosis in HL-60 cells. Recombinant lentiviral expression vector pcDNA-EF1-CAV1 was constructed, and cotransfected the 293TN cells with a mixture of pPACK packaging plasmids. Then collecting virus suspension infects the HL-60 cells, which make CAV1 gene stable transfection and high expression in the cells. The CAV1 protein expression status in HL-60 cells transfected was evaluated through Western blot method. Proliferative activity and apoptosis of HL-60 cells before and after transfection were detected by CCK-8 method and flow cytometry, respectively. The results showed that the PCR-positive clone screening and results of nucleotide sequencing confirmed that the CAV1 gene inserted into the expression vector pcDNA-EF1-GFP correctly, recombinant lentiviral particles Lv-CAV1 transfected HL-60 cells successfully and with transfection rate up to 90%. The result of Western blot showed that CAV1 protein expression in HL-60 cells significantly increased at 48 hours after transfection. CCK-8 result indicated that cell proliferation activity increased at 48 h after transfection (P < 0.05), flow cytometry testing results displayed that apoptosis rate of HL-60 cells obviously decreased after transfection (P < 0.01). It is concluded that the overexpression of CAV1 in HL-60 cells can inhibit cell proliferation activity and promote cell apoptosis.


Assuntos
Apoptose , Caveolina 1/metabolismo , Proliferação de Células , Lentivirus/genética , Caveolina 1/genética , Vetores Genéticos , Células HL-60 , Humanos , Plasmídeos , Transfecção
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