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1.
Epigenetics Chromatin ; 16(1): 33, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37740218

RESUMO

BACKGROUND: Breast cancer, the most common malignancy in women worldwide, has been proven to have both altered plasma cell-free DNA (cfDNA) methylation and fragmentation profiles. Nevertheless, simultaneously detecting both of them for breast cancer diagnosis has never been reported. Moreover, although fragmentation pattern of cfDNA is determined by nuclease digestion of chromatin, structure of which may be affected by DNA methylation, whether cfDNA methylation and fragmentation are biologically related or not still remains unclear. METHODS: Improved cfMeDIP-seq were utilized to characterize both cfDNA methylation and fragmentation profiles in 49 plasma samples from both healthy individuals and patients with breast cancer. The feasibility of using cfDNA fragmentation profile in hypo- and hypermethylated regions as diagnostic markers for breast cancer was evaluated. RESULTS: Mean size of cfDNA fragments (100-220 bp) mapped to hypomethylated regions decreased more in patients with breast cancer (4.60 bp, 172.33 to 167.73 bp) than in healthy individuals (2.87 bp, 174.54 to 171.67 bp). Furthermore, proportion of short cfDNA fragments (100-150 bp) in hypomethylated regions when compared with it in hypermethylated regions was found to increase more in patients with breast cancer in two independent discovery cohort. The feasibility of using abnormality of short cfDNA fragments ratio in hypomethylated genomic regions for breast cancer diagnosis in validation cohort was evaluated. 7 out of 11 patients were detected as having breast cancer (63.6% sensitivity), whereas no healthy individuals were mis-detected (100% specificity). CONCLUSION: We identified enriched short cfDNA fragments after 5mC-immunoprecipitation (IP) in patients with breast cancer, and demonstrated the enriched short cfDNA fragments might originated from hypomethylated genomic regions. Furthermore, we proved the feasibility of using differentially methylated regions (DMRs)-dependent cfDNA fragmentation profile for breast cancer diagnosis.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Metilação de DNA , Ácidos Nucleicos Livres/genética , Cromatina , Genômica
2.
Adv Sci (Weinh) ; 10(11): e2205873, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36782089

RESUMO

Triple-negative breast cancer (TNBC) is a highly lethal malignancy with limited therapy options. TWIST1, a key transcriptional factor of epithelial-mesenchymal transition (EMT), contributes to self-renewal of cancer stem-like cells (CSCs), chemo-resistance, metastasis, and TNBC-related death. However, the mechanism by which TWIST1 is deregulated in TNBC remains elusive. Here, USP29 is identified as a bona fide deubiquitinase of TWIST1. The deubiquitination of TWIST1 catalyzed by USP29 is required for its stabilization and subsequent EMT and CSC functions in TNBC, thereby conferring chemotherapeutic resistance and metastasis. Furthermore, the results unexpectedly reveal that CDK1 functions as the direct USP29 activator. Mechanistically, CDK1-mediated phosphorylation of USP29 is essential for its deubiquitinase activity toward TWIST1 and TWIST1 driven-malignant phenotypes in TNBC, which could be markedly mitigated by the genetic ablation or pharmacological inhibition of CDK1. Moreover, the histological analyses show that CDK1 and USP29 are highly upregulated in TNBC samples, which positively correlate with the expression of TWIST1. Taken together, the findings reveal a previously unrecognized tumor-promoting function and clinical significance of the CDK1-USP29 axis through stabilizing TWIST1 and provide the preclinical evidence that targeting this axis is an appealing therapeutic strategy to conquer chemo-resistance and metastasis in TNBC.


Assuntos
Proteína Quinase CDC2 , Neoplasias de Mama Triplo Negativas , Proteína 1 Relacionada a Twist , Proteases Específicas de Ubiquitina , Humanos , Proteína Quinase CDC2/metabolismo , Linhagem Celular Tumoral , Enzimas Desubiquitinantes , Proteínas Nucleares/metabolismo , Fosforilação , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteína 1 Relacionada a Twist/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Carcinogênese/genética
3.
PeerJ ; 10: e13641, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855425

RESUMO

Background: Recent studies have shown that long non-coding RNAs (lncRNAs) may play key regulatory roles in many malignant tumors. This study investigated the use of novel lncRNA biomarkers in the diagnosis and prognosis of breast cancer. Materials and Methods: The database subsets of The Cancer Genome Atlas (TCGA) by RNA-seq for comparing analysis of tissue samples between breast cancer and normal control groups were downloaded. Additionally, anticoagulant peripheral blood samples were collected and used in this cohort study. The extracellular vesicles (EVs) from the plasma were extracted and sequenced, then analyzed to determine the expressive profiles of the lncRNAs, and the cancer-related differentially expressed lncRNAs were screened out. The expressive profiles and associated downstream-mRNAs were assessed using bioinformatics (such as weighted correlation network analysis (WGCNA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) enrichments, Receiver-Operating Characteristic (ROC) curve and survival analysis, etc.) to investigate the diagnostic and prognostic values of these EV lncRNAs and their effectors. Results: In this study, 41 breast cancer-related lncRNAs were screen out from two datasets of tissue and fresh collected plasma samples of breast cancer via the transcriptomic and bioinformatics techniques. A total of 19 gene modules were identified with WGCNA analysis, of which five modules were significantly correlated with the clinical stage of breast cancer, including 28 lncRNA candidates. The ROC curves of these lncRNAs revealed that the area under the curve (AUC) of all candidates were great than 70%. However, eight lncRNAs had an AUC >70%, indicating that the combined one has a good diagnostic value. In addition, the results of survival analysis suggested that two lncRNAs with low expressive levels may indicate the poor prognosis of breast cancer. By tissue sample verification, C15orf54, AL157935.1, LINC01117, and SNHG3 were determined to have good diagnostic ability in breast cancer lesions, however, there was no significant difference in the plasma EVs of patients. Moreover, survival analysis data also showed that AL355974.2 may serve as an independent prognostic factor and as a protective factor. Conclusion: A total of five lncRNAs found in this study could be developed as biomarkers for breast cancer patients, including four diagnostic markers (C15orf54, AL157935.1, LINC01117, and SNHG3) and a potential prognostic marker (AL355974.2).


Assuntos
Neoplasias da Mama , RNA Longo não Codificante , Feminino , Humanos , Neoplasias da Mama/diagnóstico , Estudos de Coortes , Biologia Computacional , Prognóstico , RNA Longo não Codificante/genética , Curva ROC
4.
Int Immunopharmacol ; 108: 108911, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35729838

RESUMO

Hepatocellular carcinoma (HCC) is a common malignant tumour in China that remains a major challenge to the medical community, and effective treatment is urgently needed. Due to complex tumorigenesis, monotherapy shows poor therapeutic effects, and combined treatment becomes a necessary option. YW002, a CpG ODN-containing sequence, has been proven to enhance antitumor effects in tumour-bearing mouse models. Moreover, as a broad-spectrum antimicrobial drug, nifuroxazide exhibited an anti-HCC effect through activation of p-Stat3. Here, we tested the effect of nifuroxazide on HCC in vitro and then explored the therapeutic effect of combined nifuroxazide and CpG ODN on HCC in vivo. Nifuroxazide inhibited proliferation, induced apoptosis and suppressed migration and invasion in HepG2 cells in vitro. The combination therapy using nifuroxazide and CpG ODN significantly suppressed the growth of tumours in tumour-bearing mice with few side effects and achieved better therapeutic effects on HCC than monotherapy. Moreover, combined nifuroxazide and CpG ODN therapy significantly induced apoptosis, enhanced the infiltration of CD4+ and CD8+ T lymphocytes and macrophages in tumour tissue, and increased the ratio of CD4+ and CD8+ T lymphocytes in the spleens of tumour-bearing mice. The introduction of this combination therapy combining nifuroxazide and CpG ODN provided a new strategy for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nitrofuranos , Adjuvantes Imunológicos/uso terapêutico , Animais , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Hidroxibenzoatos/farmacologia , Hidroxibenzoatos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Nitrofuranos/uso terapêutico , Oligodesoxirribonucleotídeos/farmacologia
5.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887374

RESUMO

Millimeter-wave (MMW) imaging scanners can see through clothing to form a three-dimensional holographic image of the human body and suspicious objects, providing a harmless alternative for non-contacting searches in security check. Suspicious object detection in MMW images is challenging, since most of them are small, reflection-weak, shape, and reflection-diverse. Conventional detectors with artificial neural networks, like convolution neural network (CNN), usually take the problem of finding suspicious objects as an object recognition task, yielding difficulties in developing large-amount and complete sample sets of objects. In this paper, a new algorithm is developed using the human pose segmentation followed by the deep CNN detection. The algorithm is emphasized to learn the similarity with humans' body clutter applied to training corresponding CNNs after the image segmentation base of the pose estimation. Moreover, the suspicious object recognition in the MMW image is converted to a binary classification task. Instead of recognizing all sorts of suspicious objects, the CNN detector determines whether the body part images present the abnormal patterns containing suspicious objects. The proposed algorithm that is based on CNN with the pose segmentation has concise configuration, but optimal performance in the suspicious object detection. Extensive experiments confirm the effectiveness and superiority of the proposal.

6.
Oncol Lett ; 18(6): 6829-6835, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31788126

RESUMO

Metastasis, which involves the spread of cancer cells to distant tissues and organs, is a major cause of cancer-associated mortality. Although the use of anesthetics and analgesics may affect cancer cell metastasis, the underlying molecular mechanism remains unclear. Autophagy is a lysosome-based dynamic intracellular catabolic process that serves a crucial role in cancer cell metastasis. In order to investigate the role of autophagy in the migration of cancer cells treated with analgesics, immunofluorescence, western blotting, wound healing assay and cell invasion assay were performed in the present study. The results from immunofluorescence and western blotting demonstrated that the opioid analgesic sufentanil stimulated LC3 induction in NCI-H460 cells. Furthermore, sufentanil increased LC3 and Beclin1 protein levels, but inhibited the fusion of autophagosomes and lysosomes. In addition, sufentanil decreased cathepsin D protein level and increased p62 protein level. The addition of chloroquine (CQ) to sufentanil did not induce a further increase in LC3-II protein levels in NCI-H460 cells, suggesting the impairment of autophagic degradation. Furthermore, treatment with trehalose stimulated the migration of sufentanil-treated cells, whereas additional treatment with CQ did not further decrease the migration of sufentanil-treated cells. In addition, sufentanil co-treatment with trehalose significantly increased the invasion of lung cancer cells, whereas, additional treatment with CQ did not further reduce the invasion of sufentanil-treated cells. These results indicated that autophagy may be involved in the inhibition of NCI-H460 cell migration by sufentanil, and that sufentanil may be considered as a favorable analgesic for patients with lung cancer.

7.
Front Public Health ; 7: 344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824910

RESUMO

Background: The growth rate of centenarians was unusually rapid in recent decades, ushering in an era of longevity. This study aims to explore the difference between centenarians and non-centenarians using quantitative research, and to scientifically guide residents to develop the correct lifestyle and health care ways. Methods: From October 2013 to August 2017. A cross-sectional survey was conducted on 271 centenarians and 570 non-centenarians by using a questionnaire to assess longevity and health issues which was developed for the needs of the study, who came from 29 counties and districts in 11 cities of Zhejiang province, China. Two hundred and fifty-five valid questionnaires were returned, with an effective response rate of 94.1%. Meanwhile, data of 526 non-centenarians from Zhejiang province was collected as a control group, with an effective response rate of 92.3%. Results: The prevalence rates of tumor, stomach and duodenal ulcer, diabetes, bronchial asthma, and chronic obstructive pulmonary disease, tuberculosis among centenarians were all lower than those among non-centenarians. The oral health of centenarians is better than that of non-centenarians. The consumption of coarse cereals, pasta, other staple foods and fruits among centenarians was higher than that of non-centenarians. The percentage of centenarians who smoke or engage in recreational activities every day was lower than that of non-centenarians. Conclusions: We should give full play to the role of preventive medicine and health management to safeguard the health of residents. Pay attention to oral health, and develop the good habit of loving teeth. The diet should be rich and varied, and increase the intake of grains and fruits. Give up smoking, limit alcohol, spirit-preserving with calming, follow the law of scientific regimen.

8.
Med Sci Monit ; 25: 1526-1536, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30808858

RESUMO

BACKGROUND This study aimed to investigate cognitive function, hippocampal neuronal changes, and the expression of inflammatory cytokines in a mouse model of hepatic ischemia-reperfusion injury. MATERIAL AND METHODS Sixty mice were divided into the sham group, which underwent surgery without vascular occlusion; the I/R1 group, with occlusion of the left hepatic artery and portal vein for 20 min, and reperfusion for 30 min; and the I/R2 group, with occlusion of the left hepatic artery and portal vein for 40 min, and reperfusion for 30 min. At postoperative day 4 and 11, ten mice from each group underwent the Morris water maze (MWM) task. Hippocampal tissues were stained for Nissl bodies. Expression of nuclear factor-κB (NF-κB) and choline acetyltransferase (ChAT) were quantified by immunohistochemistry. Serum tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS Groups I/R1 and I/R2 showed a significantly increased latency in the MWM test between days 5-9, compared with the sham group (P<0.05), with no difference by day 11; the I/R2 group had an initial lower crossing frequency (P<0.05), with no difference by day 18. The I/R2 group showed reduced numbers of Nissl bodies in hippocampal neurons. The I/R1 and I/R2 groups had increased expression of NF-κB, TNF-α, and IL-1ß and decreased ChAT. No differences between the groups were found in levels of NF-κB, TNF-α, IL-1ß, or ChAT by day 18. CONCLUSIONS A mouse model of hepatic ischemia-reperfusion injury showed transient and reversible cognitive dysfunction, changes in hippocampal neurons, and expression of inflammatory cytokines.


Assuntos
Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Animais , China , Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , Fígado/lesões , Masculino , Camundongos , NF-kappa B/metabolismo , Neurônios/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
World J Gastroenterol ; 24(8): 941-948, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491687

RESUMO

AIM: To observe gene polymorphisms of TPMT and NUDT15, and compare their predictive value for azathioprine (AZA)-induced leukopenia in inflammatory bowel disease (IBD). METHODS: This study enrolled 219 patients diagnosed with IBD in Xiangya Hospital, Central South University, Changsha, China from February 2016 to November 2017. Peripheral blood of all patients was collected to detect their genotypes of TPMT and NUDT15 by pyrosequencing at the Department of Clinical Pharmacology, Hunan Key Laboratory of Pharmacogenetics, Xiangya Hospital. Eighty patients were treated with AZA according to the disease condition. During the first month, patients who received AZA underwent routine blood tests and liver function tests once a week. The endpoint of the study was leukopenia induced by AZA. By analyzing patient characteristics, genotypes and leukopenia induced by drug use, we found the risk factors associated with AZA-induced leukopenia. RESULTS: There were 219 patients with IBD (160 men and 59 women), including 39 who were confirmed with ulcerative colitis (UC), 176 with Crohn's disease (CD) and 4 with undetermined IBD (UIBD). There were 44 patients (20.1%) with mutant genotype of NUDT15 (C/T); among them, 16 received AZA, and 8 (50%) developed leukopenia. There were 175 patients (79.7%) with wild genotype of NUDT15 (C/C); among them, 64 received AZA, and 11 (17.2%) developed leukopenia. A significant difference was found between NUDT15 C/T and its wild-type C/C (P = 0.004). There were only 3 patients with TPMT mutant genotype of A/G (1.4%) who participated in the research, and 1 of them was treated with AZA and developed leukopenia. The remaining 216 patients (98.6%) were found to bear the wild genotype of TPMT (A/A); among them, 79 patients received AZA, and 18 (22.8%) developed leukopenia, and there was no significant difference from those with A/G (P = 0.071). The frequency of TPMT mutation was 1.4%, and NUDT15 mutation rate was significantly higher and reached 20.1% (P = 0.000). Therefore, NUDT15 gene polymorphism was obviously a better biomarker than TPMT gene polymorphism in the prediction of AZA-induced leukopenia. CONCLUSION: Mutation rate of NUDT15 in Chinese IBD patients is higher than that of TPMT. NUDT15 polymorphism is a better predictor for AZA-induced leukopenia than TPMT polymorphism.


Assuntos
Azatioprina/efeitos adversos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Leucopenia/genética , Metiltransferases/genética , Pirofosfatases/genética , Adulto , Povo Asiático/genética , Biomarcadores/análise , Estudos de Coortes , Feminino , Técnicas de Genotipagem/métodos , Humanos , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/genética , Leucopenia/induzido quimicamente , Leucopenia/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo Genético , Valor Preditivo dos Testes , Fatores de Risco , Adulto Jovem
10.
ACS Appl Mater Interfaces ; 9(23): 19963-19972, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28537373

RESUMO

A novel lead-free (1 - x)CaTiO3-xBiScO3 linear dielectric ceramic with enhanced energy-storage density was fabricated. With the composition of BiScO3 increasing, the dielectric constant of (1 - x)CaTiO3-xBiScO3 ceramics first increased and then decreased after the composition x > 0.1, while the dielectric loss decreased first and increased. For the composition x = 0.1, the polarization was increased into 12.36 µC/cm2, 4.6 times higher than that of the pure CaTiO3. The energy density of 0.9CaTiO3-0.1BiScO3 ceramic was 1.55 J/cm3 with the energy-storage efficiency of 90.4% at the breakdown strength of 270 kV/cm, and the power density was 1.79 MW/cm3. Comparison with other lead-free dielectric ceramics confirmed the superior potential of CaTiO3-BiScO3 ceramics for the design of ceramics capacitors for energy-storage applications. First-principles calculations revealed that Sc subsitution of Ti-site induced the atomic displacement of Ti ions in the whole crystal lattice, and lattice expansion was caused by variation of the bond angles and lenghths. Strong hybridization between O 2p and Ti 3d was observed in both valence band and conduction band; the hybridization between O 2p and Sc 3d at high conduction band was found to enlarge the band gap, and the static dielectric tensors were increased, which was the essential for the enhancement of polarization and dielectric properties.

11.
Oncol Rep ; 35(3): 1868-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26717879

RESUMO

All-trans retinoic acid (ATRA) has been shown to enhance the expression of connexin 43 (Cx43) and the bystander effect (BSE) in suicide gene therapy. These in turn improve effects of suicide gene therapies for several tumor types. However, whether ATRA can improve BSE remains unclear in suicide gene therapy for breast cancer. In the present study, MCF-7, human breast cancer cells were treated with ATRA in combination with a VEGFP-TK/CD gene suicide system developed by our group. We found that this combination enhances the efficiency of cell killing and apoptosis of breast cancer by strengthening the BSE in vitro. ATRA also promotes gap junction intercellular communication (GJIC) in MCF-7 cells by upregulation of the connexin 43 mRNA and protein in MCF-7 cells. These results indicate that enhancement of GJIC by ATRA in suicide gene system might serve as an attractive and cost-effective strategy of therapy for breast cancer cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Conexina 43/biossíntese , Genes Transgênicos Suicidas , Terapia Genética , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Efeito Espectador , Conexina 43/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Tretinoína/administração & dosagem
12.
Exp Ther Med ; 10(5): 1720-1724, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26640542

RESUMO

C-X-C chemokine receptor 7 (CXCR7) is a known promoter of tumor progression and metastasis; however, little is known about its role in colon cancer. The aim of the present study was to investigate the function of CXCR7 in human colon cancer cells. CXCR7 mRNA levels were examined in HT-29 and SW-480 human colon cancer cell lines using a quantitative polymerase chain reaction. CXCR7-knockdown was performed with small interfering RNA and lentiviral-mediated gene delivery. Immunofluorescence (IF) was conducted to examine CXCR7 expression and localization in colon cancer cells. Cell survival and migration were evaluated using MTT and migration assays, respectively. HT-29 cells expressed higher levels of CXCR7 mRNA and were therefore used in subsequent experiments. IF staining revealed that the CXCR7 protein was expressed on the cell membrane, and its expression decreased following CXCR7-short hairpin RNA lentiviral transfection. Lentiviral CXCR7-knockdown resulted in decreased cell survival and migration; however, MTT assays revealed that the lentiviral vector itself was cytotoxic. This cytotoxicity was indicated as the cell survival of the negative control group cells was significantly decreased compared with that of the blank control group cells (P<0.05). In conclusion, it is becoming increasingly evident that CXCR7 plays a role in colon cancer promotion, suggesting that CXCR7 is a promising biomarker for chemokine receptor-based drug development. Furthermore, the fact that CXCR7 is expressed on the membrane and not intracellularly makes it a prime target for drug-based intervention.

13.
J BUON ; 20(3): 707-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26214621

RESUMO

PURPOSE: To investigate the effect of quercetin on the reversal of tamoxifen resistance in breast cancer cells, and explore the underlying mechanism. METHODS: We established a tamoxifen-resistant breast cancer cell line (MCF-7Ca/TAM-R), and exposed it to different concentrations of quercetin (experimental group 1: 10 µM, group 2: 25 µM, and group 3: 50µM). Each group was further subdivided into 2 subgroups: 1) simultaneous administration of quercetin and 4-hydroxytamoxifen (OHT); 2) sequential administration of quercetin (12-h induction) followed by OHT. No drug exposure and OHT alone were used as controls. We determined cell survival, apoptosis, and expression of ERα (estrogen receptor α) and Her-2 (human epidermal growth factor receptor 2). RESULTS: With increasing dosage of quercetin, significant decrease in proliferation and increase in apoptosis was observed. Low concentrations of quercetin (10 µM) had no effects. We found no significant difference between simultaneous and sequential mode of drug administration. Further, with increasing dosage of quercetin, we observed a gradual reduction in Her-2 expression and upregulation of ERα. Again, no difference in Her-2 and ERα protein levels between simultaneous and sequential drug administration was noticed. CONCLUSIONS: Proliferation inhibition and apoptosis in MCF-7Ca/TAM-R cells increase with increasing dosage of quercetin. This suggests that quercetin can reverse tamoxifen resistance in breast cancer cells. The underlying mechanism likely involves upregulation of ERα combined with downregulation of Her-2. However, this effect is independent of whether quercetin and tamoxifen are administered simultaneously or sequentially.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antagonistas de Estrogênios/farmacologia , Quercetina/farmacologia , Tamoxifeno/análogos & derivados , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Receptor ErbB-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia , Fatores de Tempo
14.
J BUON ; 18(1): 51-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23613388

RESUMO

PURPOSE: To investigate the effects and the possible molecular mechanisms of metformin on HER2 positive breast cancer cells. METHODS: SK-BR-3 HER2 positive breast cancer cells were treated with different concentrations of metformin. The growth inhibitory rate of the cells was calculated by MTT assay, apoptosis was detected by flow cytometry, and the expression level of heat shock protein 90 (HSP90) was performed by Western blot analysis. A control group consisted of cells treated with PBS. RESULTS: With increased concentrations of metformin, cell growth inhibitory rates increased. The growth inhibitory rates with 0.5 mM, 2mM or 8mM metformin were significantly higher compared with the control group (p<0.05). Apoptosis in the metformin treated cells was also significantly higher compared with the control group (p=0.003). The expression level of HSP90 in the metformin group was significantly lower than that in the control group. CONCLUSION: Metformin can inhibit the proliferation and promote apoptosis of HER2 positive breast cancer cells,which is maybe related to inhibition of HSP90.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/metabolismo , Metformina/farmacologia , Receptor ErbB-2/metabolismo , Western Blotting , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo , Feminino , Citometria de Fluxo , Humanos , Fatores de Tempo
15.
Cancer Biol Ther ; 10(2): 190-7, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20505319

RESUMO

Colorectal cancer (CRC) is one of the leading causes of cancer-related mortality worldwide. MicroRNAs (miRs) are single-stranded, noncoding RNAs that are important in many biological processes. Although the oncogenic and tumor-suppressive functions of several miRs have been characterized, their precise biological roles remain largely unexplored. In the present study, the role of miR-133b was identified in the regulation of CRC cell proliferation and apoptosis. miR-133b expression was shown to be greatly downregulated in human CRC cells compared to normal colon cells. Downregulation of miR-133b expression was also significant in six of eight human CRC tissues compared with adjacent normal tissues. In the CRC cell lines SW-620 and HT-29, ectopic expression of miR-133b potently affected tumor cell proliferation and apoptosis in vitro and in vivo by direct targeting of the receptor tyrosine kinase MET. Transfection of SW-620 and HT-29 cells with miR-133b significantly suppressed a luciferase-reporter containing the MET-3'-untranslated region. Taken together, these results provide evidence that miR-133b regulated tumor cell proliferation and apoptosis through modulation of the MET signaling pathway.


Assuntos
Carcinoma/genética , Neoplasias Colorretais/genética , MicroRNAs/genética , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas c-met/genética , Receptores de Fatores de Crescimento/genética , Análise de Variância , Animais , Apoptose , Carcinoma/metabolismo , Carcinoma/patologia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-met/metabolismo , RNA Neoplásico/genética , Receptores de Fatores de Crescimento/metabolismo , Transdução de Sinais , Estatísticas não Paramétricas , Carga Tumoral , Células Tumorais Cultivadas
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 73(5): 972-5, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19493695

RESUMO

In this paper, two flavonoid aglycones (baicalein, quercetin) and their glycosides (baicalin, quercitrin) were studied for their ability to bind protein by quenching the protein intrinsic fluorescence. From the spectra obtained, the bimolecular quenching constants, the apparent static binding constants, and binding sites values were calculated. The glycosylation of flavonoids decreases the binding affinity with protein. For quercetin and quercitrin, the binding constants for BSA were 3.65 x 10(7) and 6.47 x 10(3)L mol(-1), respectively. For baicalein and baicalin, the binding constants were 4.54 x 10(8) and 1.63 x 10(6)L mol(-1), respectively.


Assuntos
Flavanonas/metabolismo , Flavonoides/metabolismo , Quercetina/análogos & derivados , Quercetina/metabolismo , Soroalbumina Bovina/metabolismo , Animais , Sítios de Ligação , Bovinos , Flavanonas/química , Flavonoides/química , Glicosilação , Estrutura Molecular , Ligação Proteica , Quercetina/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência
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