Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 13.619
Filtrar
1.
Anticancer Res ; 39(10): 5361-5367, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570430

RESUMO

BACKGROUND/AIM: The mechanism responsible for B-cell translocation gene 1 (BTG1) down-regulation in breast carcinoma remains unknown. We examined the BTG1 expression status in breast carcinoma cells and investigated the mechanism underlying the observed alterations. MATERIALS AND METHODS: Four breast carcinoma cell lines (SK-BR-3, MDA-MB-231, T-47D, and MCF-7), and one normal mammary epithelial cell line (MCF-10A) were analyzed. BTG1 expression was examined using quantitative reverse transcription polymerase chain reaction (PCR) and western blot. Methylation status of the BTG1 promoter was analyzed using methylation-specific PCR (MSP). To investigate the effect of methylation on BTG1, the cells were treated with a demethylating agent. RESULTS: The carcinoma cells expressed significantly lower levels of BTG1 mRNA and protein than normal cells. The BTG1 promoter was highly methylated in the carcinoma cells. 5-aza-2-deoxycytidine significantly restored BTG1 expression. CONCLUSION: Down-regulation of BTG1 expression through epigenetic repression is involved in mammary carcinogenesis. BTG1 is a potential diagnostic marker and therapeutic target for breast carcinoma.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA/genética , Regulação para Baixo/genética , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Epigênese Genética/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , RNA Mensageiro/genética
2.
Biol Res ; 52(1): 55, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601259

RESUMO

BACKGROUND: Epanorin (EP) is a secondary metabolite of the Acarospora lichenic species. EP has been found in lichenic extracts with antimicrobial activity, and UV-absorption properties have been described for closely related molecules; however, its antiproliferative activity in cancer cells has not yet been explored. It has been hypothesized that EP inhibits cancer cell growth. MCF-7 breast cancer cells, normal fibroblasts, and the non-transformed HEK-293 cell line were exposed to increasing concentrations of EP, and proliferation was assessed by the sulforhodamine-B assay. RESULTS: MCF-7 cells exposed to EP were examined for cell cycle progression using flow cytometry, and DNA fragmentation was examined using the TUNEL assay. In addition, EP's mutagenic activity was assessed using the Salmonella typhimurium reverse mutation assay. The data showed that EP inhibits proliferation of MCF-7 cells, and it induces cell cycle arrest in G0/G1 through a DNA fragmentation-independent mechanism. Furthermore, EP's lack of overt cytotoxicity in the normal cell line HEK-293 and human fibroblasts in cell culture is supported by the absence of mutagenic activity of EP. CONCLUSION: EP emerges as a suitable molecule for further studies as a potential antineoplastic agent.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Líquens/química , Antineoplásicos/isolamento & purificação , Fragmentação do DNA , Feminino , Citometria de Fluxo , Humanos , Células MCF-7
3.
Isr Med Assoc J ; 21(7): 504, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31507133

RESUMO

BACKGROUND: Klotho is a transmembrane protein that can be shed and can act as a circulating hormone in three forms: soluble klotho (KL1 + KL2), KL1, and KL2. Klotho was discovered as a gene implicated in aging through inhibition of the IGF-I pathway. Our laboratory discovered the role of klotho as a tumor suppressor in breast cancer and other malignancies. Furthermore, we showed that the KL1 domain mediates this activity. Altered cancer cell metabolism is a hallmark of cancer and our lab demonstrated various effects of klotho on breast cancer cell metabolism. Thus, klotho inhibited glycolysis and activated adenosine monophosphate activating kinase (AMPK), an energy sensor pathway. Moreover, inhibition of AMPK reduced the tumor suppressor activity of klotho. OBJECTIVES: To assess the effect of KL1 on breast tumor cells metabolism, as KL1 possesses the tumor suppressor activity of klotho. METHODS: We used MCF-7 breast cancer cells treated with soluble or over-expressed KL1 and klotho. Glycolysis was assessed by measuring mRNA levels of key glycolytic enzymes using reverse transcription polymerase chain reaction and by measuring lactate and glucose levels in media. The AMPK pathway was studied by monitoring AMPK phosphorylation as well as its down-stream target, acetyl-CoA carboxylase, using western blotting. Wound healing assay was used to assess cell migration. RESULTS: KL1 treatment reduced glycolytic enzymes mRNA levels and the activity of hexokinase, similar to klotho treatment. Furthermore, KL1 reduced glucose uptake and decreased lactate production. KL1 elevated phosphorylated acetyl-CoA carboxylase and phosphorylated AMPK levels. Inhibition AMPK (using a mutant AMPK activator) stopped KL1 from inhibiting cell migration, suggesting AMPK underlies klotho's tumor suppressor activity. CONCLUSIONS: Our data indicate KL1 as a regulator of metabolic activity in breast cancer and suggest that metabolic alterations underlie KL1 tumor suppressor activities. Furthermore, as KL1 and klotho share a similar effect on cell metabolism, our results further support the central role KL1 domain plays in klotho's tumor suppressor activity.


Assuntos
Neoplasias da Mama/metabolismo , Glucuronidase/metabolismo , Glicólise/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Movimento Celular/fisiologia , Feminino , Humanos , Células MCF-7 , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Medicine (Baltimore) ; 98(36): e17009, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490383

RESUMO

Erythrina corallodendron L., a kind of landscape tree, has long been used as a traditional medicine. In this study, the composition of essential oil extracted from the leaves was analysed by GC-MS (gas chromatograph-mass spectrometer), with linalool identified as the main compound. Its cytotoxicity against MDA-MB-231, MCF-7 and HMLE cells was examined by MTT and cloning assays. Transwell and wound-healing assays were used to examine the inhibition of migration and invasion. Western blot, qRT-PCR and immunofluorescence staining were used to measure the mRNA and protein expression of factors related to EMT (snail, slug, E-cadherin, N-cadherin and vimentin). The essential oil of Erythrina corallodendron leaves was found to inhibit the proliferation, migration and invasion of breast cancer cells in a dose-dependent manner. The findings of this study suggest that the essential oil of E. corallodendron leaves may merit further investigation as a potential clinical or adjuvant drug for treating breast cancer migration and invasion.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/análise , Neoplasias da Mama/tratamento farmacológico , Erythrina/química , Óleos Voláteis/uso terapêutico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Células MCF-7 , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/farmacologia , Fitoterapia , Folhas de Planta/química
5.
Chem Commun (Camb) ; 55(77): 11619-11622, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501844

RESUMO

Mesoporous organosilica nanoparticles (PHT-PMO) have been prepared from an octa-triethoxysilylated Zn phthalocyanine precursor. These PHT-PMO nanoparticles had no dark toxicity but high phototoxicity when irradiated at 650 nm, and remarkable near-infrared phototoxicity when excited at 760 and 810 nm. The PHT-PMO were then aminated to promote electrostatic complexation with siRNA. Transfection experiments were performed upon NIR irradiation and photochemical internalization was very efficient, leading to 65% luciferase extinction in MCF-7 cancer cells expressing stable luciferase.


Assuntos
Indóis/química , Nanopartículas/química , Compostos Organometálicos/química , Fotoquimioterapia/métodos , RNA Interferente Pequeno/química , Silanos/química , Sobrevivência Celular , Cetrimônio/química , Humanos , Raios Infravermelhos , Luciferases/genética , Células MCF-7 , Processos Fotoquímicos , Porosidade , RNA Interferente Pequeno/metabolismo , Eletricidade Estática , Propriedades de Superfície
6.
Chem Commun (Camb) ; 55(67): 9967-9970, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31367705

RESUMO

Herein, a seesaw ratiometric (SR) probe is designed which integrates fluorescence and surface enhanced Raman scattering (SERS) technology. Fluorescence imaging enables tracking of the spatiotemporal dynamic behaviour of telomerase. Meanwhile, SERS reverse ratiometric measurement can enable sensitive detection of telomerase activity in single living cells.


Assuntos
Corantes/química , Imagem Óptica/métodos , Análise de Célula Única/métodos , Análise Espectral Raman/métodos , Telomerase/metabolismo , DNA/química , Transferência Ressonante de Energia de Fluorescência/métodos , Ouro/química , Humanos , Células MCF-7 , Nanopartículas Metálicas/química
7.
Life Sci ; 234: 116756, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419444

RESUMO

AIMS: Conventional radiotherapy is mainly restricted by the low radiation absorption efficiency of tumors tissues and the hypoxic tumor cells radio-resistance. In this paper, novel nano-radiosensitizers, magnetic nanoparticles core coated with silica, were successfully prepared to overcome these limitations. MAIN METHODS: The prepared nanoparticles have been characterized by transmission electron microscope (TEM), Dynamic light scattering (DLS), atomic force microscope (AFM) and vibration sample magnetometer (VSM). MTT cytotoxicity and DNA double-strand breaks (Comet) assays have been used to assess the radio-enhancing effect of iron oxide magnetic nanoparticles (IO-MNPs) and silica-coated iron oxide magnetic nanoparticles (SIO-MNPs) against MCF7 breast cancer cells. MCF7 cells were treated with different concentrations of the prepared nanoformulations and exposed to an electron beam at doses 0, 0.5, 1, 2, 4 Gy. KEY FINDINGS: DLS measurements revealed that the main hydrodynamic diameter of the prepared IO-MNPs and SIO-MNPs was 18.17 ±â€¯4.5 nm and 164.18 ±â€¯16.1 nm, respectively, which was confirmed by TEM micrographs. MTT and comet assays results showed that the radiosensitizing effect of the prepared nanoformulations was dose and concentration dependent. Interestingly, the dose enhancement factor (DEF) for SIO-MNPs was, on average, 1.3-fold greater than that of IO-MNPs. SIGNIFICANCE: Coating of IO-MNPs with silica led to enhance their electron radiosensitization and consequently their therapeutic efficacy. Therefore, SIO-MNPs represent a promising engineered nano-formulation for enhancing breast cancer radiosensitivity.


Assuntos
Neoplasias da Mama/radioterapia , Compostos Férricos/uso terapêutico , Nanopartículas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Dióxido de Silício/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos da radiação , Dano ao DNA/efeitos da radiação , Elétrons , Feminino , Compostos Férricos/química , Humanos , Células MCF-7 , Nanopartículas/química , Radiossensibilizantes/química , Dióxido de Silício/química
8.
Adv Exp Med Biol ; 1155: 543-553, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468430

RESUMO

Taurine transporter (TauT) has been identified as a target gene of p53 tumor suppressor. TauT is also found to be overexpressed in variety type of human cancers, such as leukemia. This study showed that expression of TauT was upregulated by c-Myc and c-Jun oncogenes. To explore whether blocking of TauT inhibits tumor development, the RNA interference (RNAi) and immune targeting approaches were tested in tumor cells in vitro and in p53 mutant mice in vivo. Knockdown of TauT expression by RNAi resulted in cell cycle G2 arrest and suppressed human breast cancer MCF-7 cells proliferation determined by colonies production and cell migration assays. Knockdown of TauT also rendered MCF-7 cells more susceptible to chemotherapeutic drug-induced apoptosis. An antibody specifically against TauT blocked taurine uptake and induced cell cycle G2 arrest leading to cell death of variety type of tumor cells without affecting the viability of normal mammalian cells. TauT peptide vaccination significantly increased median lifespan (1.5-fold) of the p53 null mice and rescued p53+/- mice by extending the median lifespan from 315 days to 621 days. Furthermore, single dose treatment of tumor-bearing (thymic lymphoma) p53 null mice with TauT peptide reduced tumor size by about 50% and significantly prolonged survival of these mice from average 7 days (after observing the thymic lymphoma) to 21 days. This finding demonstrates that a novel TauT peptide vaccine can delay, inhibit, and/or treat p53 mutation related spontaneous tumorigenesis in vivo. Therefore, TauT peptide may be used as a universal cancer vaccine to prevent and/or treat patients with p53 mutation-mediated cancers.


Assuntos
Vacinas Anticâncer , Imunoterapia , Glicoproteínas de Membrana , Proteínas de Membrana Transportadoras , Interferência de RNA , Proteína Supressora de Tumor p53/genética , Animais , Anticorpos Monoclonais/farmacologia , Pontos de Checagem do Ciclo Celular , Técnicas de Silenciamento de Genes , Genes jun , Genes myc , Humanos , Células MCF-7 , Camundongos , Camundongos Knockout , Terapia de Alvo Molecular , Mutação , Taurina , Vacinas de Subunidades
9.
Int J Nanomedicine ; 14: 5073-5085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371948

RESUMO

Purpose: To potentiate the anticancer activity of curcumin (CUR) by improving its cell penetration potentials through formulating it into nanostructured lipid carriers (NLCs) and using the prepared NLCs in photodynamic therapy. Methods: A 3×4 factorial design was used to obtain 12 CUR-NLCs using two factors on different levels: (1) the solid lipid type at four levels and (2) the solid to liquid lipid ratio at three levels. Olive oil, Tween 80 and lecithin were chosen as liquid lipid, surfactant and co-surfactant, respectively. CUR-NLCs prepared by high shear hot homogenization method were evaluated by determination of particle size (PS), polydispersity index, zeta potential (ZP), entrapment efficiency percent, drug loading percent and in vitro drug release. Optimization was based on the evaluation results using response surface modeling (RSM). Optimized formulae were tested for their in vitro release pattern and for dark and photo-cytotoxic anticancer activity on breast cancer cell line in comparison to free CUR. Results: Evaluation tests showed the appropriateness of NLCs prepared from glyceryl monooleate and Geleol™ helped choosing two optimized formulae, PE3 and GE3. PE3 (prepared using glyceryl monooleate) showed enhanced release rates compared to GE3 (prepared from Geleol) and superior cytotoxic anticancer activity compared to both GE3 and free CUR under both light and dark conditions. The small mean PS, spherical shape as well as the negative ZP enhanced the internalization of the NLCs within cells. Modulation and inhibition of P-glycoprotein expression by glyceryl monooleate synergized the cytotoxic activity of CUR. Conclusion: CUR loading in NLCs enhanced its cell penetration and cytotoxic anticancer properties both in dark and in light conditions.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Curcumina/uso terapêutico , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Ácidos Oleicos/química , Azeite de Oliva/química , Fotoquimioterapia , Sobrevivência Celular/efeitos dos fármacos , Curcumina/farmacologia , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática
10.
Anticancer Res ; 39(8): 4031-4041, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366485

RESUMO

BACKGROUND/AIM: Eribulin is currently used to treat advanced and metastatic breast cancer in the clinical setting; however, its efficacy is inhibited by resistance acquisition in many cases. Thus, the present study established two eribulin-resistant breast-cancer cell lines, and used these to investigate the mechanisms that underly eribulin-resistance acquisition. MATERIALS AND METHODS: Eribulin-resistant breast-cancer cell lines were generated by culturing MDA-MB-231 and MCF-7 cells with increasing concentrations of eribulin. RESULTS: The eribulin-resistant cells acquired resistance to eribulin, as well as several other anticancer drugs. After eribulin treatment, the eribulin-resistant cell lines showed no morphological change, no increased expression of epithelial-cadherin, nor any significant alteration in cell-cycle distribution. In contrast, the expression levels of programmed death-ligand 1 were increased in the MCF-7/eribulin-resistant compared to MCF-7 cells. CONCLUSION: The herein developed eribulin-resistant cell lines acquired cross-resistance to various anticancer agents, and displayed resistance to eribulin-induced effects on microtubule function and epithelial-mesenchymal transition (EMT).


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Furanos/administração & dosagem , Cetonas/administração & dosagem , Animais , Antineoplásicos/efeitos adversos , Mama/efeitos dos fármacos , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Furanos/efeitos adversos , Humanos , Cetonas/efeitos adversos , Células MCF-7 , Camundongos , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Anticancer Res ; 39(8): 4043-4053, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366486

RESUMO

BACKGROUND/AIM: Triple-negative breast cancer (TNBC) is the most aggressive subtype, predominant in African American women. In this study, the antioxidant/anticancer activity of muscadine grape extracts and the role of their phenolic and flavonoid contents in exerting these properties were investigated in TNBC cells. MATERIALS AND METHODS: Berry extracts from muscadine genotypes were investigated for total phenolic content (TPC), total flavonoid content (TFC), antioxidant capacity, and anticancer effects using breast cancer cell lines, representing Caucasians and African Americans. RESULTS: The antioxidant activity was associated with high TPC content. Extracts showed cytotoxicity up to 78.6% in Caucasians and 90.7% in African American cells, with an association with high antioxidant capacity. There was a strong correlation between TPC and anticancer/antioxidant activities. CONCLUSION: The anticancer and antioxidant effects of muscadine grapes are attributed to the TPC of extracts, which showed a stronger positive correlation with growth inhibition of African American breast cancer cells compared to Caucasians.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Vitis/química , Afro-Americanos/genética , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Feminino , Flavonoides/química , Flavonoides/farmacologia , Frutas/química , Humanos , Células MCF-7 , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
12.
Pharm Res ; 36(10): 140, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367876

RESUMO

PURPOSE: In order to overcome the obstacles and side effects of classical chemotherapy, numerous studies have been performed to develop the treatment based on targeted transport of active compounds directly to the site of action. Since tumor cells are featured with intensified glucose metabolism, we set out to develop innovative, glucose-modified PAMAM dendrimer for the delivery of doxorubicin to breast cancer cells. METHODS: PAMAM-dox-glc conjugate was synthesized and characterized by 1H NMR, FT-IR, size and zeta potential measurements. The drug release rate from conjugate was evaluated by dialysis under different pH conditions. The expression level of GLUT family receptors in cells cultured in full and glucose-deprived medium was evaluated by quantitative real-time RT-PCR and flow cytometry. The cytotoxicity of conjugate in presence or absence of GLUT1 inhibitors was determined by MTT assay. RESULTS: We showed that PAMAM-dox-glc conjugate exhibits pH-dependent drug release and increased cytotoxic activity compared to free drug in cells cultured in medium without glucose. Further, we proved that these cells overexpress transporters of GLUT family. The toxic effect of conjugate was eliminated by the application of specific GLUT1 inhibitors. CONCLUSION: Our findings revealed that the glucose moiety plays a crucial role in the recognition of cells with high expression of GLUT receptors. By selectively blocking GLUT1 transporter we showed its importance for the cytotoxic activity of PAMAM-dox-glc conjugate. These results suggest that PAMAM-glucose formulations may constitute an efficient platform for the specific delivery of anticancer drugs to tumor cells overexpressing transporters of GLUT family.


Assuntos
Antineoplásicos/farmacologia , Dendrímeros/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Transportador de Glucose Tipo 1/metabolismo , Glucose/efeitos adversos , Antineoplásicos/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Regulação da Expressão Gênica , Glucose/química , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Tamanho da Partícula
13.
Gene ; 716: 144032, 2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31377316

RESUMO

Mitochondrial folate metabolism is central to the generation of nucleotides, fuelling methylation reactions, and redox homeostasis. Uniquely among the reactions of the mitochondrial folate pathway, the key step of the oxidation of 5,10-methylene-tetrahydrofolate (CH2-THF) can be catalysed by two isozymes, MTHFD2 and MTHFD2L. The MTHFD2 enzyme has recently received considerable attention as an oncogenic enzyme upregulated in several tumour types, which is additionally required by cancer cells in vitro and in vivo. However, much less is currently known about MTHFD2L and its expression in cancer. In this study, we examine and compare the expression and regulation of the two mitochondrial MTHFD isozymes in normal human and cancer cells. We found that normal and cancer cells express both enzymes, although MTHFD2 has a much higher baseline expression. Unlike MTHFD2, the MTHFD2L isozyme does not show an association with proliferation and growth factor stimulation. In addition, we did not find evidence of a compensatory increase of MTHFD2L following suppression of its isozyme. This study supports that MTHFD2L is unlikely to have an important function in increased proliferation or cancer. Furthermore, therapeutic strategies aiming to block the mitochondrial folate pathway in cancer should focus on MTHFD2, with MTHFD2L being unlikely to be involved in the development of chemoresistance to targeting of its mitochondrial isozyme.


Assuntos
Aminoidrolases/metabolismo , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Enzimas Multifuncionais/metabolismo , Neoplasias/enzimologia , Aminoidrolases/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Isoenzimas/genética , Isoenzimas/metabolismo , Células MCF-7 , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Enzimas Multifuncionais/genética , Neoplasias/genética , Regulação para Cima
14.
Acta Crystallogr C Struct Chem ; 75(Pt 8): 1091-1101, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31380792

RESUMO

A new set of differently hydrated barium and strontium squarates, namely poly[[triaqua(µ-1,2-dioxocyclobut-3-ene-1,2-diolato)barium] monohydrate], {[Ba(C4O4)(H2O)3]·H2O}n (1), poly[[diaqua(µ-1,2-dioxocyclobut-3-ene-1,2-diolato)strontium] monohydrate], {[Sr(C4O4)(H2O)2]·H2O}n (2), and poly[[triaqua(µ-1,2-dioxocyclobut-3-ene-1,2-diolato)barium/strontium(0.85/0.15)] monohydrate], {[Ba0.85Sr0.15(C4O4)(H2O)3]·H2O}n (3), is reported. The study of their crystal structures indicates that all the complexes crystallize in the triclinic space group P-1. Complexes 1 and 3 have a rare combination of squarate units coordinated through monodentate O atoms to two different metal atoms and through two bidentate O atoms to three different metal atoms. Furthermore, they have three coordinated water molecules to give a coordination number of nine. The squarate ligands in complex 2 exhibit two different coordination modes: (i) monodentate O atoms coordinated to four different Sr atoms and (ii) two monodentate O atoms coordinated to two different metal atoms with the other two O atoms bidentate to four different Sr atoms. All the compounds decompose to give the respective carbonates when heated to 800 °C, as evidenced by thermogravimetry/differential thermal analysis (TG-DTA), which are clusters of nanoparticles. Complexes 1 and 3 show additional endothermic peaks at 811 and 820 °C, respectively, indicating the phase transition of BaCO3 from an orthorhombic (α-Pmcn) to a trigonal phase (ß-R3m). All three complexes have significant DNA-binding constants, ranging from 2.45 × 104 to 9.41 × 104 M-1 against EB-CT (ethidium bromide-calf thymus) DNA and protein binding constants ranging from 1.1 × 105 to 8.6 × 105 with bovine serum albumin. The in vitro cytotoxicity of the complexes is indicated by the IC50 values, which range from 128.8 to 261.3 µg ml-1. Complex 3 shows better BSA binding, antioxidant activity against the DPPH radical and cytotoxicity than complexes 1 and 2.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Ciclobutanos/farmacologia , Depuradores de Radicais Livres/farmacologia , Substâncias Intercalantes/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/metabolismo , Bário/química , Bovinos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Cristalografia por Raios X , Ciclobutanos/síntese química , Ciclobutanos/química , Ciclobutanos/metabolismo , DNA/metabolismo , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/metabolismo , Humanos , Ligações de Hidrogênio , Substâncias Intercalantes/síntese química , Substâncias Intercalantes/química , Substâncias Intercalantes/metabolismo , Ligantes , Células MCF-7 , Estrutura Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Estrôncio/química , Água/química
15.
Int J Nanomedicine ; 14: 4529-4539, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417256

RESUMO

Purpose: Here, we fabricated two plasmonic 2D Ti3C2Tx-based nanocomposites (Au/MXene and Au/Fe3O4/MXene) with similarly high anti-cancer photothermal therapy (PTT) capabilities, but with less in vivo toxicity than a pure MXene. Methods: Au/MXene was synthesized by in situ reduction of tetrachloroauric acid using NaBH4 on Ti3C2Tx flakes. For targeted PTT, magnetic Au/Fe3O4/MXene was synthesized via a reaction between freshly prepared magnetite Fe3O4 NPs and MXene solution, followed by in situ integration of gold nanoparticles (AuNPs). Results: Morphological characterization by XRD, SEM, and TEM revealed the successful synthesis of Au/MXene and Au/Fe3O4/MXene. Both new composites exhibited a significant in vitro dose-dependent PTT effect against human breast cancer cells MCF7. Interestingly, in vivo acute toxicity assays using zebrafish embryos indicated that Au/MXene and Au/Fe3O4/MXene had less embryonic mortality (LC50 ≫ 1000 µg/mL) than pure MXene (LC50=257.46 µg/mL). Conclusion: Our new Au/MXene and Au/Fe3O4/MXene nanocomposites could be safer and more suitable than the pure MXene for biomedical applications, especially when targeted PTT is warranted.


Assuntos
Hipertermia Induzida , Nanocompostos/uso terapêutico , Fototerapia , Titânio/química , Testes de Toxicidade Aguda , Animais , Sobrevivência Celular/efeitos dos fármacos , Embrião não Mamífero/efeitos dos fármacos , Humanos , Células MCF-7 , Nanocompostos/ultraestrutura , Teratogênios/toxicidade , Difração de Raios X , Peixe-Zebra
16.
Cancer Sci ; 110(10): 3098-3109, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31389121

RESUMO

Lysosomal-associated protein transmembrane 4 beta (LAPTM4B), a proto-oncogene, has been shown to be a positive modulator in cancer progression. However, the mechanism of LAPTM4B regulation is not fully elucidated. Aberrant microRNAs (miRNAs) can regulate gene expression by interfering with target transcripts and/or translation to exert tumor-suppressive or oncogenic effects in breast cancer. In the present study, miR-132-3p, which was predicted by relevant software, was confirmed to directly bind to the 3' untranslated region (3'UTR) of LAPTM4B and negatively regulate its expression in luciferase reporter and western blot assays. Subsequently, we validated that miR-132-3p was downregulated in breast cancer tissues. Receiver-operating characteristic curve analysis indicated that miR-132-3p had accurate diagnostic value, and a Kaplan-Meier and Cox regression model showed that miR-132-3p was a potential prognostic marker for recurrence, showing low levels in breast cancer patients. In addition, we showed that miR-132-3p was inversely correlated with LAPTM4B expression in the above samples. Functionally, miR-132-3p suppressed the migration and invasion of breast carcinoma cells through LAPTM4B by mediating epithelial-mesenchymal transition signals, and partially reversed the carcinogenic effects of LAPTM4B by inhibiting the PI3K-AKT-mTOR signaling pathway. Taken together, these findings provide the first comprehensive analysis of miR-132-3p as a direct LAPTM4B-targeted miRNA, and shed light on miR-132-3p/LAPTM4B as a significant functional axis involved in the oncogenesis and metastasis of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , MicroRNAs/genética , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Regiões 3' não Traduzidas , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Invasividade Neoplásica , Estadiamento de Neoplasias , Curva ROC , Transdução de Sinais , Análise de Sobrevida
17.
Cancer Sci ; 110(10): 3157-3172, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432600

RESUMO

The underlying mechanisms of breast cancer cells metastasizing to distant sites are complex and multifactorial. Bone sialoprotein (BSP) and αvß3 integrin were reported to promote the metastatic progress of breast cancer cells, particularly metastasis to bone. Most theories presume that BSP promotes breast cancer metastasis by binding to αvß3 integrin. Interestingly, we found the αvß3 integrin decreased in BSP silenced cells (BSPi), which have weak ability to form bone metastases. However, the relevance of their expression in primary tumor and the way they participate in metastasis are not clear. In this study, we evaluated the relationship between BSP, αvß3 integrin levels, and the bone metastatic ability of breast cancer cells in patient tissues, and the data indicated that the αvß3 integrin level is closely correlated to BSP level and metastatic potential. Overexpression of αvß3 integrin in cancer cells could reverse the effect of BSPi in vitro and promote bone metastasis in a mouse model, whereas knockdown of αvß3 integrin have effects just like BSPi. Moreover, The Cancer Genome Atlas data and RT-PCR analysis have also shown that SPP1, KCNK2, and PTK2B might be involved in this process. Thus, we propose that αvß3 integrin is one of the downstream factors regulated by BSP in the breast cancer-bone metastatic cascade.


Assuntos
Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Integrina alfaVbeta3/metabolismo , Sialoproteína de Ligação à Integrina/metabolismo , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Quinase 2 de Adesão Focal/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Inativação Gênica , Humanos , Sialoproteína de Ligação à Integrina/genética , Células MCF-7 , Camundongos , Transplante de Neoplasias , Osteopontina/genética , Canais de Potássio de Domínios Poros em Tandem/genética
18.
Tumour Biol ; 41(8): 1010428319869101, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31423948

RESUMO

Stemness phenotype mammospheres established from cell lines and tissues taken from autopsy can be used to test and to identify the most sensitive drugs for chemotherapy. Therefore, the aim of the present study was isolation and characterization of cancer stem cells derived from MCF7, MDA-MB231, and SKBR3 breast cancer cell lines to demonstrate the stemness phenotypes of mammospheres generated for further their applications in therapeutic approaches. In this study, two luminal subtypes of cell lines, MCF7 and SKBR3 and a basal subtype cell line, MDA-MB-231, were chosen. Mammosphere culturing was implemented for breast cancer stem cells isolation and mammosphere formation efficiency. At the next step, CD44+/CD24- cell ratio, Oct4 and Nanog mRNA levels, proliferation rate, migration rate of mammospheres, and drug resistance (in third passage) were evaluated. In addition, tumorigenicity of mammospheres in the chick embryo model was evaluated and compared through the chick chorioallantoic membrane assay. Among mammospheres formed in all three cell lines, MCF7 had the highest mammosphere formation efficiency. CD24 marker (a differentiation marker for the breast cancer cells) was significantly reduced in the mammospheres generated from MCF7 and SKBR3, during three passages. Also, Oct4 and Nanog transcript levels were significantly higher in all three types of mammospheres, as compared with their cell lines. Proliferation, migration rate, and drug resistance of mammospheres generated from all three cell lines were found to be significantly higher. Tumorigenicity of MCF7 mammospheres was confirmed through tumor size measurement. Also, tumorigenicity of MCF7 and SKBR3 mammospheres was confirmed through more migration from ectoderm to mesoderm and endoderm. We succeeded to establish the technology that can be extended to tissue in the future. We have demonstrated a number of mammospheres can be generated from cell lines. Also, cells with different molecular features showed different stemness phenotypes.


Assuntos
Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/patologia , Células-Tronco Neoplásicas/patologia , Esferoides Celulares/patologia , Animais , Antígeno CD24/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Embrião de Galinha , Membrana Corioalantoide/citologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Receptores de Hialuronatos/metabolismo , Células MCF-7 , Proteína Homeobox Nanog/genética , Fator 3 de Transcrição de Octâmero/genética , RNA Mensageiro/genética , Células Tumorais Cultivadas
19.
Int J Nanomedicine ; 14: 5713-5728, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413571

RESUMO

Purpose: The levels of reactive oxygen species (ROS) in tumor cells are much higher than that in normal cells, and rise rapidly under the influence of exogenous or endogenous inducing factors, eventually leading to the apoptosis of tumor cells. Therefore, this study prepared a dual pH/reducing-responsive poly (N-isopropylacrylamide-co-Cinnamaldehyde-co-D-α-tocopheryl polyethylene glycol 1000 succinate, PssNCT) nanogels, which employed two exogenous ROS inducers, cinnamaldehyde (CA) and D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS), to selectively induce apoptosis by regulating ROS levels in tumor cells. Methods: The PssNCT nanogels were prepared by the free radical precipitation polymerization under the crosslink between pH-sensitive hydrazone and reducing-sensitive disulfide bonds, followed by the physicochemical and morphological characteristics investigations. Plasma stability, dual pH/reducing responsive degradation and in vitro release were also assessed. In cell experiments, cytotoxicity in different cells were first detected. The intracellular ROS levels and mitochondrial functions of tumor cells were then evaluated. Moreover, the apoptosis and western-blot assays were employed to verify the association between ROS levels elevation and apoptosis in tumor cells. Results: The nanogels exhibited a round-like hollow structure with the diameter smaller than 200nm. The nanogels were stable in plasma, while showed rapid degradation in acidic and reducing environments, thus achieving significant release of CA and TPGS in these media. Furthermore, the sufficient amplification of ROS signals was induced by the synergistically function of CA and TPGS on mitochondria, which resulted in the opening of the mitochondrial apoptotic pathway and enhanced cytotoxicity on MCF-7 cells. However, nanogels barely affected L929 cells owing to their lower intracellular ROS basal levels. Conclusion: The specific ROS regulation method achieved by these nanogels could be explored to selectively kill tumor cells according to the difference of ROS signals in different kinds of cells.


Assuntos
Apoptose , Espaço Intracelular/química , Polietilenoglicóis/farmacologia , Polietilenoimina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Acroleína/análogos & derivados , Acroleína/farmacologia , Animais , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Vitamina E/síntese química , Vitamina E/química
20.
Fitoterapia ; 137: 104262, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284018

RESUMO

Eight undescribed 9,19-cycloartane type triterpenoid glycosides (cimdalglnoside A-H) and ten known analogues were obtained from the phytochemical research on the roots of Actaea dahurica (syn. Cimicifuga dahurica). All compounds were characterised by spectroscopic experiments, and chemical method. All the compounds isolated were assayed for cytotoxicity to five human cancer cell lines. Cimdalglnoside G showed promising cytotoxicities against Hela, and MCF-7 cell lines with IC50 values at 7.7 and 12.2 µM.


Assuntos
Actaea/química , Glicosídeos/farmacologia , Raízes de Plantas/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , China , Glicosídeos/isolamento & purificação , Células HeLa , Humanos , Células MCF-7 , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Triterpenos/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA