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1.
J Sports Sci Med ; 23(2): 487-494, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38841646

RESUMO

Small-sided games (SSGs) are frequently utilized in training settings to elicit specific stimuli that can promote physical fitness adaptations over time. However, various task constraints, such as pitch dimensions, can significantly influence both the acute external and internal load responses. Thus, understanding the impact of different pitch dimensions on physical fitness adaptations is crucial. This study sought to compare the physical adaptations induced by an SSG-based program utilizing more elongated pitches (SSGlw2; length-to-width ratio: 2.0) versus less elongated pitches (SSGwl1; length-to-width ratio: 1.0) on the Yo-Yo intermittent recovery test level 1 (YYIRT), and 30-meter sprint. This study employed a randomized controlled design. Forty-eight male soccer players (16.4 ± 0.6 years) participated. These players were randomly allocated to two experimental groups (N = 16, SSGlw1; N = 16, SSGlw2) and underwent two weekly additional training sessions over an 8-week period, while a group of 16 players continued with their regular in-field sessions as a control group. Evaluations were conducted before and after the intervention period. Significant interactions time u group were observed in regards YYIRT (F = 15.857; p < 0.001; = 0.413) and 30-m sprint test (p < 0.001). Between-group differences on YYIRT were found in post-intervention (p < 0.001), on which SSGlw2 (p < 0.001) and SSGlw1 (p < 0.001) were significantly greater in comparison to control group. Additionally, between-group differences on 30-m sprint were found in post-intervention (p < 0.001), on which SSGlw2 was significantly better than SSGlw1 (p < 0.001) and control group (p < 0.001). Coaches are advised to prioritize the use of more elongated pitch sizes to promote adaptations in sprint performance, while still acknowledging that aerobic capacity improvements remain significant compared to other pitch shapes.


Assuntos
Adaptação Fisiológica , Condicionamento Físico Humano , Aptidão Física , Futebol , Humanos , Futebol/fisiologia , Masculino , Adolescente , Aptidão Física/fisiologia , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Desempenho Atlético/fisiologia , Corrida/fisiologia , Teste de Esforço
2.
Biochem Biophys Res Commun ; 505(4): 996-1002, 2018 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-30314706

RESUMO

Recently, a large number of studies have shown that circular RNA (circRNA) is involved in the development and progression of human cancer. However, its role in triple-negative breast cancer (TNBC) remains largely unknown. In this study, a novel circRNA, circ-UBAP2 (hsa_circ_0001846), was shown to be markedly upregulated in TNBC. Moreover, high circ-UBAP2 expression was closely associated with larger tumour size (p = 0.003), advanced TNM stage (p = 0.005), lymph node metastasis (p = 0.002), and unfavourable prognosis (p = 0.0256). Functionally, lentivirus-mediated stable knockdown of circ-UBAP2 dramatically weakened the ability of TNBC cells to proliferate and migrate and induced apoptosis in vitro and in vivo. Regarding the mechanism, we found that circ-UBAP2 was mainly observed in the cytoplasm and was capable of sponging miRNA-661 to increase the expression of the oncogene MTA1. Additionally, silencing of miRNA-661 or overexpression of MTA1 could partially rescue the attenuated malignant phenotype caused by circ-UBAP2 knockdown. Taken together, our data reveal that circ-UBAP2 plays a vital regulatory role in TNBC via the miR-661/MTA1 axis and may serve as a promising therapeutic target for TNBC patients.


Assuntos
Histona Desacetilases/metabolismo , MicroRNAs/metabolismo , RNA/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias de Mama Triplo Negativas/diagnóstico , Regulação para Cima , Animais , Feminino , Humanos , Neoplasias Mamárias Experimentais/diagnóstico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Circular , Transativadores , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas
3.
Cancer Cell Int ; 14: 79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25788862

RESUMO

BACKGROUND: Aberrant DNA methylation is an acquired epigenetic alteration that serves as an alternative to genetic defects in the inactivation of tumor suppressor genes and other genes in diverse human cancers. Gastric carcinoma is one of the tumors with a high frequency of aberrant methylation in promoter region. Hence we investigated the promoter methylation status and expression level of HOXA11 gene which may involve in GC development. METHODS: Thirty-two surgical excised gastric cancer specimens, twelve paired adjacent non-cancerous specimens and seven normal gastric mucosas were examined. The methylation status and expression level of HOXA11 gene were determined by bisulfite sequencing polymerase chain reaction (BSP), real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) respectively. HOXA11 expression was knocked-down with siRNA to mimic HOXA11 gene hypermethylation and ability of cell proliferation and migration was determinate. In addition, we analyzed and correlated the findings with clinicopathological features. RESULTS: The methylation level of HOXA11 gene in gastric cancer tissues and adjacent non-cancerous tissues were higher than those in normal gastric mucosa (P < 0.05). The methylation level was higher in TNM III and IV patients of GC than those in TNM I and II patients (P < 0.05). The expression of HOXA11 mRNA and protein decreased in normal gastric mucosa, peri-cancer tissue and GC (P < 0.05). HOXA11 expression was inversely correlated with DNA methylation (P < 0.05). Knocked-down of HOXA11 expression with siRNA in BGC-823 cells enhanced cell proliferation compared with control, but no significant different was observed in migration ability. CONCLUSION: Hypermethylation and decreased expression of HOXA11 gene may be involved in the carcinogenesis and development of GC and may provide useful information for the prediction of the malignant behaviors of GC. And the expression of HOXA11 is impaired by DNA methylation. However, repression of HOXA11 expression promoted BGC-823 cell proliferation.

4.
Cancer Cell Int ; 13(1): 67, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23819802

RESUMO

BACKGROUND: In order to search for new structural modification strategies on fluoroquinolones, we have designed and synthesized a series of fluoroquinolone derivatives by linking various hydrazine compounds to the C-3 carboxyl group of levofloxacin and assessed their anticancer activities. Several novel levofloxacin derivatives displayed potent cytotoxicity against the tested cancer cell lines in vitro. In the present study, we investigated the effect of 1-Cyclopropyl-6-fluoro-4-oxo-7- piperazin-1, 4-dihydro- quinoline- 3-carboxylic acid benzo [1,3] dioxol-5- ylmethylene- hydrazide (QNT11) on the apoptosis of human hepatocarcinoma cells in vitro. METHODS: The inhibition effects of QNT11 on cell proliferation were examined by MTT assay. Cell apoptosis was determined by TUNEL and DNA agarose gel electrophoresis method. The topoisomerase ΙΙ activity was measured by agarose gel electrophoresis using Plasmid pBR322 DNA as the substrate. Cell cycle progression was analyzed using flow cytometry in conjunction with ethanol fixation and propidium iodide staining. Mitochondrial membrane potential (△ψm) was measured by high content screening image system. The caspase-9, caspase-8, caspase-3, Bcl-2, Bax, CDK1, Cyclin B1and cytochrome c protein expressions were detected by Western blot analysis. RESULTS: QNT11 showed selective cytotoxicity against Hep3B, SMMC-7721, MCF-7 and HCT-8 cell lines with IC50 values of 2.21 µM, 2.38 µM, 3.17 µM and 2.79 µM, respectively. In contrast, QNT11 had weak cytotoxicity against mouse bone marrow mesenchymal stem cells (BMSCs) with IC50 value of 7.46 µM. Treatment of Hep3B cells with different concentrations of QNT11 increased the percentage of the apoptosis cells significantly, and agarose gel electrophoresis revealed the ladder DNA bands typical of apoptotic cells, with a decrease in the mitochondrial membrane potential. Compared to the control group, QNT11 could influence the DNA topoisomerase IIactivity and inhibit the religation of DNA strands, thus keeping the DNA in fragments. There was a significant increase of cytochrome c in the cytosol after 24 h of treatment with QNT11 and a decrease in the mitochondrial compartment. Observed changes in cell cycle distribution by QNT11 treated might be caused by insufficient preparation for G2/M transition. In addition, QNT11 increased the protein expression of Bax, caspase-9, caspase-8, caspase-3, as well as the cleaved activated forms of caspase-9, caspase-8 and caspase-3 significantly, whereas the expression of Bcl-2 decreased. CONCLUSIONS: Our results showed that QNT11 as a fluoroquinolone derivative exerted potent and selectively anticancer activity through the mechanism of eukaryotic topoisomerase II poisoning. The growth inhibition was in large part mediated via apoptosis-associated mitochondrial dysfunction and regulation of Bcl-2 signaling pathways.

5.
Acta Pharmacol Sin ; 33(2): 271-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22301863

RESUMO

AIM: To investigate the cytotoxic effects of piperonal ciprofloxacin hydrazone (QNT4), a novel antibacterial fluoroquinolone derivative, against human hepatocarcinoma SMMC-7721 cells. METHODS: Human hepatocarcinoma cells (SMMC-7721), human breast adenocarcinoma cells (MCF-7) and human colon adenocarcinoma cells (HCT-8) were tested. The effects of QNT4 on cell proliferation were examined using MTT assay. Cell apoptosis was determined using Hoechst 33258 fluorescence staining, TUNEL assay and agarose gel electrophoresis. The topoisomerase II activity was measured using agarose gel electrophoresis with the DNA plasmid pBR322 as the substrate. Mitochondrial membrane potential (Δψm) was measured using a high content screening imaging system. Protein expression of caspase-9, caspase-8, caspase-3, p53, Bcl-2, Bax, and cytochrome c was detected with Western blot analysis. RESULTS: Treatment with QNT4 (0.625-10 µmol/L) potently inhibited the proliferation of the cancer cells in time- and dose-dependent manners (the IC(50) value at 24 h in SMMC-7721 cells, MCF-7 cells and HCT-8 cells was 2.956±0.024, 3.710±0.027, and 3.694±0.030 µmol/L, respectively). Treatment of SMMC-7721 cells with QNT4 (0.2146, 2.964, and 4.600 µmol/L) for 24 h dose-dependently increased the percentage of apoptotic cells, elicited characteristic DNA "ladder" bands, and decreased the mitochondrial membrane potential. QNT4 dose-dependently increased topoisomerase II-mediated DNA breaks while inhibiting DNA relegation, thus keeping the DNA in fragments. Treatment of SMMC-7721 cells with QNT4 significantly increased cytochrome c in the cytosol, and decreased cytochrome c in the mitochondrial compartment. QNT4 (3-7.39 µmol/L) significantly increased the protein expression of p53, Bax, caspase-9, caspase-3, and the cleaved activated forms of caspase-9 and caspase-3 in SMMC-7721 cells. In contrast, the expression of Bcl-2 was decreased, while caspase-8 had no significant change. CONCLUSION: QNT4 induced the apoptosis of SMMC-7721 cells via inhibiting topoisomerase II activity and modulating mitochondrial-dependent pathways.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Ciprofloxacina/análogos & derivados , Ciprofloxacina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Feminino , Humanos , Hidrazonas/química , Hidrazonas/farmacologia , Neoplasias Hepáticas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos
6.
Yao Xue Xue Bao ; 45(9): 1109-15, 2010 Sep.
Artigo em Zh | MEDLINE | ID: mdl-21351566

RESUMO

This study is to observe the effect of N-(3-phenylallylidene)-6-fluoro-1, 8-(2, 1-propoxy)-7-(4-methylpiperazin-1-yl)-quinolin-4(1H)-one-3-carbonyl hyarazine (FQ16) on apoptosis of hepatocarcinoma SMMC-7721 cells in vitro. With different concentrations of FQ16 at different times used to treat SMMC-7721 cells in vitro, the proliferation of the cells and the inhibition effect of FQ16 on the cell proliferation were examined by MTT assay. Cell apoptosis was determined by Hoechst 33258/PI fluorescence staining, TUNEL and agarose gel electrophoresis method. The effect of FQ16 on topoisomerase II activity was measured by agarose gel electrophoresis using Plasmid pBR322 DNA as the substrate. Mitochondrial membrane potential (MMP, delta psi m) was measured by high content screening image system. The reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect the expression changes of Bcl-2 mRNA and Bax mRNA. The caspase-9, caspase-8, caspase-3, p53, Bcl-2 and Bax protein expressions were detected by Western blotting analysis. The results showed that the cell proliferation was inhibited by FQ16 at 0.625 - 10 micromol L(-1) in a time-dose dependent manner. Treatment of SMMC-7721 cells with different concentrations of FQ16 for 24 h increased the percentage of the apoptosis cells obviously (P<0.05), the typical ladder DNA in apoptotic cells and a concomitant dissipation of the mitochondrial membrane potential. Compared with control group, FQ16 influenced obviously DNA topoisomerase II activity, stimulated DNA cleavage and inhibited DNA reunion mediated by topoisomerase II. In addition, FQ16 (3 - 7.39 micromol L(-1)) increased mRNA expression of Bax and protein expression of p53, Bax, caspase-9, caspase-3, separately, and induced cytosolic accumulation of activities caspase-9 and caspase-3, whereas the mRNA and protein expression of Bcl-2 decreased with no change of caspase-8. Therefore it can be concluded that the effects of inhibited topoisomerase II and mitochondrial-dependent pathways were involved in FQ16 induction of apoptosis of SMMC-7721 cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Piperazinas/farmacologia , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Antineoplásicos/química , Carcinoma Hepatocelular/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Relação Dose-Resposta a Droga , Humanos , Neoplasias Hepáticas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Piperazinas/administração & dosagem , Piperazinas/síntese química , Piperazinas/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
7.
Cell Cycle ; 17(2): 154-161, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29179614

RESUMO

The incidence and mortality rate of colorectal cancer (CRC) have been significantly increasing. However, mechanisms involved in CRC progression are still unclear. LncRNA ZFAS1 has been verified as oncogenic molecular in a series of tumors, including CRC. However, the underlying mechanism of ZFAS1 in CRC carcinogenesis remains unclear. In the present study, our data showed that ZFAS1 expression was significantly upregulated in CRC tissues and cell lines. Correlation analysis showed that high ZFAS1 expression was significantly associated with Helicobacter pylori infection, lymph nodes metastasis, advanced TNM stage and poor overall survival of CRC patients. Loss-of-function experiments revealed that ZFAS1 inhibition could markedly suppress CRC cells proliferation and invasion both in vitro and in vivo. Bioinformatics analysis and luciferase reporter assay revealed that ZFAS1 directly interacted with miR-484. Rescue experiments showed that miR-484 inhibitor reversed the tumor suppressing roles of ZFAS1 knockdown on CRC cells. Therefore, our study suggested that ZFAS1 could act as an oncogene in CRC tumorigenesis, and discovered the functional regulatory pathway of ZFAS1 sponging miR-484.


Assuntos
Neoplasias Colorretais/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Longo não Codificante/fisiologia
8.
Cancer Manag Res ; 10: 3881-3890, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30288120

RESUMO

BACKGROUND: Accumulating evidence suggests that circular RNAs (circRNAs) play critical roles in carcinomas. However, the contributions of circRNAs to breast cancer remain unclear. Herein, we determined the role of circZNF609 in breast cancer. METHODS: A total of 143 breast cancer and 38 normal tissues were collected to assess the expression of circZNF609 and its relationship with breast cancer prognosis. A series of in vitro and in vivo functional experiments were carried out to elucidate the role of circZNF609 in breast cancer progression and its underlying molecular mechanisms. RESULTS: CircZNF609 was markedly over-expressed in breast cancer tissues and cell lines, and high circZNF609 expression was closely associated with poor outcome. Silencing of circZNF609 inhibited the malignant phenotype of breast cancer in vitro and in vivo. Mechanistically, circ-ZNF609 served as a sponge of miR-145-5p to elevate p70S6K1 expression. Moreover, miR-145-5p overexpression or p70S6K1 knockdown abrogated the oncogenic effects of circZNF609 in breast cancer. In addition, clinically, a strong negative correlation was observed between the expression of circZNF609 and miR-145-5p in breast cancer tissues (r=-0.597, P<0.001), whereas a positive correlation between circZNF609 and p70S6K1 expression (r=0.319, P<0.001). CONCLUSION: These data suggest that circZNF609 contributes to breast cancer progression, at least partly, by modulating the miR-145-5p/p70S6K1 axis, and it may be a potential therapeutic target for breast cancer.

9.
Exp Ther Med ; 9(6): 2364-2368, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26136988

RESUMO

The aim of this study was to investigate the effect of Helicobacter pylori (Hp) on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) levels in patients with gastric precancerous lesions and its clinical significance. A total of 114 patients with gastric precancerous lesions, 57 whom were positive for Hp (observation group) and 57 of whom were negative for Hp (control group), were selected for the study. The mRNA levels of COX-2 and iNOS in the gastric precancerous lesion tissue from the two groups of patients were analyzed through the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The protein expression levels of COX-2 and iNOS were analyzed using western blotting and an iNOS kit, respectively. In addition, normal human gastric mucosal GES-1 cells were cultured in vitro and stimulated by Hp for 3, 6, 9 and 12 h. The variations in the mRNA and protein levels of COX-2 and iNOS were then analyzed via RT-qPCR and western blotting. Compared with the control group, the mRNA levels of COX-2 and iNOS in the gastric tissue from the observation group were significantly increased (P<0.05). Furthermore, the expression level of COX-2 and iNOS protein in the gastric tissue from the observation group was significantly higher than that in the tissue from the control group (P<0.05). In vitro analysis showed that the COX-2 and iNOS mRNA and protein levels were significantly increased in the Hp-stimulated normal human gastric mucosal GES-1 cells compared with those in the unstimulated cells. Furthermore, the effect was time-dependent (P<0.05). In conclusion, COX-2 and iNOS are the main inflammatory markers. Hp can induce high expression levels of COX-2 and iNOS in gastric precancerous lesion tissue, which may be associated with the occurrence and development of gastric precancerous lesions.

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