RESUMEN

INTRODUCTION: Research in tumor treatment has shown promising results using extracellular vesicles (EVs) derived from immune cells. EVs derived from M1 macrophages (proinflammatory), known as M1-EVs, have properties that suppress tumor growth, making them a promising treatment tool for immune susceptible tumors such as melanoma. Here, small unaltered M1-EVs (M1-sEVs) were employed in a 3D mouse melanoma model (melanospheres) to evaluate such activity. METHODS: Macrophages were polarized and EVs were isolated by ultracentrifugation. The EVs obtained were characterized based on size, with measurements performed by dynamic light scattering and electron microscopy, and the expression profiles of microRNAs were analyzed by microarray and PCR. Melanospheres were used to evaluate the cytotoxicity of M1-sEVs. Pondering a possible future transposition from the animal model to the human, human melanoma cells were transfected with a specific miRNA, and the impact on cell proliferation was evaluated. RESULTS: The isolated EVs showed a size distribution between 50-400 nm in diameter, but preeminently in a range of 70-90 nm. M1-sEVs demonstrated a remarkable ability to reduce cell proliferation and viability in the melanospheres, leading to a decrease in their volume. M1-sEVs contained unique miRNAs, including miR-29a-3p, which exhibited significant antitumor activities according to bioinformatics analysis. Validation of the antitumor effects of miR-29a-3p was obtained by a functional evaluation, i.e., by inducing miRNA overexpression in human melanoma cells (SK-MEL-28). CONCLUSION: Although further research would be advisable, the study provides evidence supporting the potential of M1-sEVs and their miRNA load as a possible targeted immune therapy for melanoma.

Asunto(s)

Vesículas Extracelulares , Melanoma , MicroARNs , Animales , Humanos , Ratones , Melanoma/terapia , Modelos Animales de Enfermedad , Macrófagos , MicroARNs/genética

RESUMEN

Senecio spp. is one of the most frequent plant-related poisonings in cattle. Its ingestion generates the disease seneciosis, characterized by hepatic damages. Liver biopsies and serum markers dosage are tools used in diagnosis; however, many breeding cattle are undiagnosed. MicroRNAs are non-coding RNA, stable in biological fluids. Their difference in expression levels may indicate the presence of the poisoning. We analyzed the miRNA profiling to identify potential diagnostic biomarkers for Senecio brasiliensis poisoning. The expression of miR-21, miR-885, miR-122, miR-181b, miR-30a, miR-378, and let-7 f were evaluated in the serum of exposed cattle. At least one histological change was found in liver and lower quantity of albumin and high AST and ALP were also detected. MiRNAs miR-30a, miR-378, miR-21, miR-885, and miR-122 presented significantly higher expression in intoxicated animals than in healthy animals. Furthermore, miR-122, miR-885, and, especially, miR-21 signatures demonstrated high sensitivity and specificity, with potential application for detecting poisoning.

Asunto(s)

MicroARNs , Senecio , Animales , Biomarcadores , Bovinos , Hígado , MicroARNs/genética , Senecio/genética

RESUMEN

Eugenia involucrata DC. (Myrtaceae) is a native tree species from Brazil that has been scarcely studied. We investigated the phenolic composition, the antioxidant capacity and the antitumoral activity of ethanolic extracts from fruits (FE) and seeds (SE) of E. involucrata. Six anthocyanins were identified by UPLC-PDA/MS/MS in FE, being four derived from cyanidin, and the other ones derived from delphinidin and pelargonidin. Using HPLC-PDA, FE presented a larger number of phenolic compounds (epicatechin, catechin, rutin, ellagic acid, myricetin and quercetin) than SE, which did not show myricetin and quercetin. However, SE showed higher total phenolic content and generally stronger in vitro antioxidant capacity than FE, except that only FE exhibited superoxide radical scavenging activity, which may be attributed to the anthocyanins present in fruits. Additionally, only SE exhibited antitumoral activity in a pancreatic cancer cell line (PANC-1). The antitumoral mechanisms involved imbalance of antioxidant status, alteration of mitochondrial membrane potential, cytoskeleton disassembly and induction of cell death by apoptosis and necrosis. Compared to the standard antitumoral drug gemcitabine, SE exhibited higher antitumoral efficacy and selectivity index. The highest concentration of total phenolics and of specific phenolic compounds bearing antitumoral properties may be related to the antitumoral activity of SE. Our results corroborate previous data of E. involucrata as an important source of bioactive compounds and provide, for the first time, evidences of in vitro antitumoral potential of its seeds on pancreatic cancer cell line.

Asunto(s)

Antioxidantes , Eugenia , Antioxidantes/farmacología , Brasil , Frutas , Extractos Vegetales/farmacología , Semillas , Espectrometría de Masas en Tándem

RESUMEN

Acute-on-chronic liver failure (ACLF) is a condition characterized by acute decompensation of cirrhosis, associated with organ failure(s), and high short-term mortality. The microRNAs or miRNAs are small non-coding RNA molecules, stable in circulating samples such as biological fluids, and the difference in expression levels may indicate the presence, absence and/or stage of the disease. We analyzed here the miRNA profiling to identify potential diagnostic or prognostic biomarkers for ACLF. The major miRNAs discovered were validated in a cohort of patients with acute decompensation of cirrhosis grouped in no ACLF or ACLF according to EASL-CLIF definition. Relationship between serum miRNAs and variables associated with liver-damage and survival outcomes were verified to identify possible prognostic markers. Our results showed twenty altered miRNAs between no ACLF and ACLF patients, and twenty-seven in patients who died in 30 days compared with who survived. In validation phase, miR-223-3p and miR-25-3p were significantly altered in ACLF patients and in those who died in 30 days. miR-223-3p and miR-25-3p expression were associated with the lowest survival in 30 days. The decrease in miR-223-3p and miR-25-3p expression was associated with the presence of ACLF and poor prognosis. Of these, miR-25-3p was independently related to ACLF and 30-day mortality.

Asunto(s)

Insuficiencia Hepática Crónica Agudizada/mortalidad , Biomarcadores/sangre , Cirrosis Hepática/mortalidad , MicroARNs/genética , Insuficiencia Hepática Crónica Agudizada/sangre , Insuficiencia Hepática Crónica Agudizada/genética , Insuficiencia Hepática Crónica Agudizada/patología , Estudios de Casos y Controles , Femenino , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Pronóstico , Curva ROC , Índice de Severidad de la Enfermedad , Tasa de Supervivencia

RESUMEN

Glioblastoma is the most common and aggressive glioma, characterized by brain invasion capability. Being very resistant to the current therapies, since even under treatment, surgery, and chemotherapy with temozolomide (TMZ), patients achieve a median survival of one year. In the search for more effective therapies, new molecules have been designed. For nervous system cancers, molecules able to cross the blood-brain barrier are handled with priority. Accordingly, tacrine was chosen for this study and the inclusion of spiro-heterocyclic rings was done in its structure resulting in new compounds. Cytotoxic activity of tacrine derivatives was assayed using glioblastoma cell line (SF295) as well as analyzing cell death mechanism. Increased caspases activities were observed, confirming apoptosis as cell death type. Some derivatives also increased reactive oxygen species formation and decreased the mitochondrial membrane potential. Moreover, compounds acted on several glioblastoma-related proteins including p53, HLA-DR, beta-catenin, Iba-1, MAP2c, Olig-2, and IDH1. Therefore, tacrine derivatives presented promising results for the development of new glioblastoma therapy, particularly to treat those patients resistant to TMZ.

Asunto(s)

Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/patología , Proteínas de Neoplasias/fisiología , Tacrina/farmacología , Apoptosis/efectos de los fármacos , Caspasas/fisiología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitosis/efectos de los fármacos , Estructura Molecular , Terapia Molecular Dirigida , Necrosis , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Especies Reactivas de Oxígeno/metabolismo , Tacrina/análogos & derivados , Temozolomida

RESUMEN

Metastasis is the main cause of cancer-related death and requires the development of effective treatments with reduced toxicity and effective anticancer activity. Gallic acid derivatives have shown significant biological properties including antitumoral activity as shown in a previous study with octyl gallate (G8) in vitro. Thus, the aim of this work was to evaluate the antimetastatic effect of free and solid lipid nanoparticle-loaded G8 in mice in a lung metastasis model. Animals inoculated with melanoma cells presented metastasis in lungs, which was significantly inhibited by treatment with G8 and solid lipid nanoparticle-loaded G8, named G8-NVM. However, G8-treated mice showed an increase in several toxicological parameters, which were almost completely circumvented by G8-NVM treatment. This study supports the need for pharmacological studies on new potential medicinal plants to treat cancer and can provide new perspectives on using nanotechnology to improve biological activities while decreasing the chemotherapy toxicological effects of anticancer drugs.

Asunto(s)

Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Ácido Gálico/análogos & derivados , Enfermedades Renales/inducido químicamente , Enfermedades Renales/prevención & control , Lípidos/administración & dosificación , Nanopartículas/administración & dosificación , Animales , Chlorocebus aethiops , Femenino , Ácido Gálico/administración & dosificación , Ácido Gálico/efectos adversos , Ácido Gálico/química , Lípidos/química , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Nanopartículas/química , Metástasis de la Neoplasia , Especies Reactivas de Oxígeno/metabolismo , Células Vero

RESUMEN

Tumorigenesis is related to an imbalance in controlling mechanisms of apoptosis. Expression of the genes BCL-2 and BCL-xL results in the promotion of cell survival by inhibiting apoptosis. Thus, a novel approach to suppress antiapoptotic genes is the use of small interfering RNA (siRNA) in cancer cells. However, there are some limitations for the application of siRNA such as the need for vectors to pass the cell membrane and deliver the nucleic acid. In this study CaP-siRNA-PEG-polyanion hybrid nanoparticles were developed to promote siRNA delivery to cultured human breast cancer cells (MCF-7) in order to evaluate whether the silencing of antiapoptotic genes BCL-2 and BCL-xL by siRNA would increase cancer cell death. After 48 h of incubation the expression of BCL-2 and BCL-xL genes decreased to 49% and 23%, respectively. The siRNA sequence used induced cancer cell death at a concentration of 200 nM siRNA after 72 h of incubation. As the targeted proteins are related to the resistance to chemotherapeutic drugs, the nanocarriers systems were also tested in the presence of doxorubicin (DOX). The results showed a significant reduction in the CC50 of the DOX, after silencing the antiapoptotic genes. In addition, an increase in apoptotic cell counts for both incubations conditions was observed as well. In conclusion, silencing antiapoptotic genes such as BCL-2 and BCL-xL through the use of siRNA carried by hybrid nanoparticles showed to be effective in vitro, and presents a promising strategy for pre-clinical analysis, especially when combined with DOX against breast cancer.

Asunto(s)

Apoptosis/genética , Neoplasias de la Mama/terapia , Nanopartículas/uso terapéutico , ARN Interferente Pequeño/administración & dosificación , Antineoplásicos/farmacología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Supervivencia Celular/genética , Doxorrubicina/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Células MCF-7 , Nanopartículas/administración & dosificación , Nanopartículas/química , Polietilenglicoles/química , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína bcl-X/genética , Proteína bcl-X/metabolismo

RESUMEN

In light of the evidence that in contrast to most healthy tissues, several neoplasms overexpress fatty acid synthase (FASN) upon their dependence on increased lipogenesis; targeting of this protein is being considered as a valuable strategy in anticancer drug development. This can be particularly relevant for aggressive tumors such as melanoma in which FASN overexpression has been associated with increased depth of invasion and worse prognosis. We have previously shown that a sub-class of cyclic imides, the N-phenylmaleimides, presented antitumor activity against L1210 leukemia and B16F10 melanoma with evidences of interference in the energetic metabolism. Here, we aimed to investigate if some selected N-phenylmaleimides (M1 and M5) interfere with fatty acids metabolism and its relation with cancer. For that, a model of pre-adipocytes differentiation (3T3-L1 cells) and also human melanoma cells (SK-Mel-147) were used. As results, when 3T3-L1 cells were exposed to non-cytotoxic concentrations of M1 and M5 in the presence of an adipogenic cocktail, intracellular lipid content decreased by 26-36%, marking the inhibition of adipocyte differentiation. High selectivity indexes were obtained for both compounds for tumoral cells. Cell cycle phases analysis revealed a remarkable proportion of cells with DNA fragmentation after their exposure to M1 and M5. This was correlated to both apoptosis and necrosis, showed by Annexin-V/PI assay. Furthermore, M1 and M5 reduced FASN expression by 19-39%, respectively. In conclusion, M1 and M5 presented antiadipogenic and antitumoral activities. The antitumoral activity that was associated to apoptosis and necrosis is a possible consequence of the FASN reduction, which in turn, might result in a fuel decrease to cell proliferation. As it happens with antiangiogenic activity, reduction of fatty acid synthesis might be a potential target for cancer treatment in a strategy of hunger-strike, which valorizes these N-phenylmaleimides as candidates for drug development.

Asunto(s)

Adipogénesis/efectos de los fármacos , Antineoplásicos/farmacología , Ácido Graso Sintasas/genética , Maleimidas/farmacología , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Animales , Antineoplásicos/química , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Ácido Graso Sintasas/metabolismo , Citometría de Flujo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Maleimidas/química , Ratones

RESUMEN

Superparamagnetic iron oxide nanoparticles (SPIONS) were synthesized by thermal decomposition of an organometallic precursor at high temperature and coated with a bi-layer composed of oleic acid and methoxy-polyethylene glycol-phospholipid. The formulations were named SPION-PEG350 and SPION-PEG2000. Transmission electron microscopy, X-ray diffraction and magnetic measurements show that the SPIONs are near-spherical, well-crystalline, and have high saturation magnetization and susceptibility. FTIR spectroscopy identifies the presence of oleic acid and of the conjugates mPEG for each sample. In vitro biocompatibility of SPIONS was investigated using three cell lines; up to 100µg/ml SPION-PEG350 showed non-toxicity, while SPION-PEG2000 showed no signal of toxicity even up to 200µg/ml. The uptake of SPIONS was detected using magnetization measurement, confocal and atomic force microscopy. SPION-PEG2000 presented the highest internalization capacity, which should be correlated with the mPEG chain size. The in vivo results suggested that SPION-PEG2000 administration in mice triggered liver and kidney injury. FROM THE CLINICAL EDITOR: The potential use of superparamagnetic iron oxide nanoparticles (SPIONS) in the clinical setting have been studied by many researchers. The authors synthesized two types of SPIONS here and investigated the physical properties and biological compatibility. The findings should provide more data on the design of SPIONS for clinical application in the future.

Asunto(s)

Materiales Biocompatibles Revestidos/administración & dosificación , Nanopartículas de Magnetita/administración & dosificación , Polietilenglicoles/administración & dosificación , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Compuestos Férricos/administración & dosificación , Compuestos Férricos/química , Humanos , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Nanopartículas de Magnetita/química , Ratones , Ácido Oléico/química , Polietilenglicoles/química , Difracción de Rayos X

RESUMEN

Ketonic indeno[1,2-b]indole-9,10-dione derivatives, initially designed as human casein kinase II (CK2) inhibitors, were recently shown to be converted into efficient inhibitors of drug efflux by the breast cancer resistance protein ABCG2 upon suited substitutions including a N (5)-phenethyl on C-ring and hydrophobic groups on D-ring. A series of ten phenolic and seven p-quinonic derivatives were synthesized and screened for inhibition of both CK2 and ABCG2 activities. The best phenolic inhibitors were about threefold more potent against ABCG2 than the corresponding ketonic derivatives, and showed low cytotoxicity. They were selective for ABCG2 over both P-glycoprotein and MRP1 (multidrug resistance protein 1), whereas the ketonic derivatives also interacted with MRP1, and they additionally displayed a lower interaction with CK2. Quite interestingly, they strongly stimulated ABCG2 ATPase activity, in contrast to ketonic derivatives, suggesting distinct binding sites. In contrast, the p-quinonic indenoindoles were cytotoxic and poor ABCG2 inhibitors, whereas a partial inhibition recovery could be reached upon hydrophobic substitutions on D-ring, similarly to the ketonic derivatives.

Asunto(s)

Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Diseño de Fármacos , Indenos/farmacología , Indoles/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Fenoles/farmacología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/química , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Sitios de Unión , Quinasa de la Caseína II/antagonistas & inhibidores , Quinasa de la Caseína II/química , Quinasa de la Caseína II/metabolismo , Supervivencia Celular/efectos de los fármacos , Células HEK293 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Indenos/síntesis química , Indenos/metabolismo , Indoles/síntesis química , Indoles/metabolismo , Ratones , Mitoxantrona/metabolismo , Modelos Moleculares , Estructura Molecular , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/química , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Células 3T3 NIH , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Fenoles/síntesis química , Fenoles/metabolismo , Unión Proteica , Relación Estructura-Actividad , Transfección

RESUMEN

Several obstacles are encountered in conventional chemotherapy, such as drug toxicity and poor stability. Nanotechnology is envisioned as a strategy to overcome these effects and to improve anticancer therapy. Nanoemulsions comprise submicron emulsions composed of biocompatible lipids, and present a large surface area revealing interesting physical properties. Chalcones are flavonoid precursors, and have been studied as cytotoxic drugs for leukemia cells that induce cell death by different apoptosis pathways. In this study, we encapsulated chalcones in a nanoemulsion and compared their effect with the respective free compounds in leukemia and in non-tumoral cell lines, as well as in an in vivo model. Free and loaded-nanoemulsion chalcones induced a similar anti-leukemic effect. Free chalcones induced higher toxicity in VERO cells than chalcones-loaded nanoemulsions. Similar results were observed in vivo. Free chalcones induced a reduction in weight gain and liver injuries, evidenced by oxidative stress, as well as an inflammatory response. Considering the high toxicity and the side effects induced generally by all cancer chemotherapies, nanotechnology provides some options for improving patients' life quality and/or increasing survival rates.

Asunto(s)

Antineoplásicos/toxicidad , Chalconas/toxicidad , Emulsiones/química , Leucemia/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Chalconas/administración & dosificación , Chlorocebus aethiops , Sistemas de Liberación de Medicamentos/métodos , Emulsiones/administración & dosificación , Técnicas In Vitro , Leucemia L1210 , Hígado/patología , Masculino , Ratones , Terapia Molecular Dirigida , Nanopartículas/administración & dosificación , Nanopartículas/química , Estrés Oxidativo , Células Vero

RESUMEN

A series of chalcones substituted by a quinoxaline unit at the B-ring were synthesized and tested as inhibitors of breast cancer resistance protein-mediated mitoxantrone efflux. These compounds appeared more efficient than analogs containing other B-ring substituents such as 2-naphthyl or 3,4-methylenedioxyphenyl while an intermediate inhibitory activity was obtained with a 1-naphthyl group. In all cases, two or three methoxy groups had to be present on the phenyl A-ring to produce a maximal inhibition. Molecular modeling indicated both electrostatic and steric positive contributions. A higher potency was observed when the 2-naphthyl or 3,4-methylenedioxyphenyl group was shifted to the A-ring and methoxy substituents were shifted to the phenyl B-ring, indicating preferences among polyspecificity of inhibition.

Asunto(s)

Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Chalconas/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Proteínas de Neoplasias/antagonistas & inhibidores , Quinoxalinas/química , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Antineoplásicos/síntesis química , Antineoplásicos/química , Células Cultivadas , Chalconas/síntesis química , Chalconas/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HEK293 , Humanos , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad

RESUMEN

Acute lymphoblastic leukemia (ALL) is a malignant disorder caused by the proliferation of lymphoid progenitor cells and is the most common cancer in children. Cytotoxic nucleoside analogues are important chemotherapeutic agents, which are used in many cancers, including leukemias. In this study, we investigated the effects of the synthetic nucleoside analogue 1-(5,5,5-trichloro-2-methoxy-4-oxopenten-2-yl)-4-trichloromethyl-pyrimidin-2(1H)-one, named compound 3 or C3, on leukemia cell lines. The compound stimulated cell death by apoptosis, evidenced by DNA fragmentation, phosphatidylserine externalization, and caspase-3 activation. Compound 3 seemed to trigger several cell death pathways. The mitochondrial pathway was evidenced through a disturbance of mitochondrial membrane potential, strong cytochrome c liberation, decrease of antiapoptotic Bcl-2 protein expression, and caspase-9 activation. The C3 also induced caspase-8 and -12 activation, an increase in the intracellular calcium level, and an overproduction of reactive oxygen species. Increased caspase 8 activity suggests that the extrinsic pathway was activated and that the ROS production and enzyme activity alteration (glutathione S-transferase, glutathione peroxidase, catalase, and glutathione reductase) might be related to oxidative stress. Finally, the increase in calcium release, CHOP expression, and caspase-12 activity might characterize endoplasmic reticulum stress. Compound 3 was likewise cytotoxic to leukemic and melanoma human cell lines. Taken together, the results contribute to further understanding the new pyrimidine analogue as a potential chemotherapeutic drug or lead molecule.

Asunto(s)

Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Pirimidinonas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Células Jurkat , Ratones , Estructura Molecular , Estrés Oxidativo/efectos de los fármacos , Pirimidinonas/síntesis química , Pirimidinonas/química , Relación Estructura-Actividad

RESUMEN

Chalcones, naturally occurring open-chain flavonoids abundant in plants, have demonstrated anticancer activity in multiple tumor cells. In a previous work, the potential anticancer activity of three naphthylchalcones named R7, R13 and R15 was shown. In this study, the mechanism of actions of these chalcones was originally shown. The chalcones presented concentration and time-dependent cytotoxicity. To determine the type of cell death induced by chalcones, we assessed a series of assays including measurements of the caspase-8, -9 and -12 activities, expression of important apoptosis-related genes and proteins, changes in the cell calcium concentration and cytochrome c release. The activities of caspase-8, -9 and -12 increased after the treatment of L1210 cells with the three compounds. Chalcones R7 and R13 induced an increase of pro-apoptotic proteins Bax, Bid and Bak (only chalcone R13), as well as a decrease in anti-apoptotic Bcl-2 expression. These chalcones also induced an increase in Fas and a decrease in p21 and p53 expression. Chalcone R15 seems to act by a different mechanism to promote cell death, as it did not change the mitochondrion-related proteins, nor did it induce the cytochrome c release. All compounds induced an increase in cell calcium concentration and an increase in CHOP expression, which together with an increase in caspase-12 activity, suggest that chalcones could induce an endoplasmic reticulum (ER) stress. Taken together, these results suggest that chalcones induce apoptosis by different pathways, being an interesting strategy to suggest for cancer therapy.

Asunto(s)

Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Chalconas/farmacología , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Calcio/metabolismo , Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Citocromos c/metabolismo , Estrés del Retículo Endoplásmico , Expresión Génica , Leucemia/tratamiento farmacológico , Leucemia/metabolismo , Ratones , Células 3T3 NIH , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Células Vero , Receptor fas/genética , Receptor fas/metabolismo

RESUMEN

Adenosine triphosphate-binding cassette subfamily G member 2 (ABCG2) plays a major role in cancer cell multidrug resistance, which contributes to low efficacy of chemotherapy. Chalcones were recently found to be potent and specific inhibitors, but unfortunately display a significant cytotoxicity. A cellular screening against ABCG2-mediated mitoxantrone efflux was performed here by flow cytometry on 54 chalcone derivatives from three different series with a wide panel of substituents. The identified leads, with submicromolar IC50 (half maximal inhibitory concentration) values, showed that the previously identified 2'-OH-4',6'-dimethoxyphenyl, as A-ring, could be efficiently replaced by a 2'-naphthyl group, or a 3',4'-methylenedioxyphenyl with lower affinity. Such a structural variability indicates 3polyspecificity of the multidrug transporter for inhibitors. At least two methoxyl groups were necessary on B-ring for optimal inhibition, but substitution at positions 3, 4, and 5 induced cytotoxicity. The presence of a large O-benzyl substituent at position 4 and a 2'-naphthyl as A-ring markedly decreased the cytotoxicity, giving a high therapeutic ratio, which constitutes a critical requirement for future in-vivo assays in animal models.

Asunto(s)

Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Antineoplásicos/farmacología , Chalconas/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Transporte Biológico , Chalconas/administración & dosificación , Chalconas/química , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Citometría de Flujo , Células HEK293 , Humanos , Concentración 50 Inhibidora , Mitoxantrona/farmacocinética , Relación Estructura-Actividad

RESUMEN

Based on classical colchicine site ligands and a computational model of the colchicine binding site on beta tubulin, two classes of chalcone derivatives were designed, synthesized and evaluated for inhibition of tubulin assembly and toxicity in human cancer cell lines. Docking studies suggested that the chalcone scaffold could fit the colchicine site on tubulin in an orientation similar to that of the natural product. In particular, a 3,4,5-trimethoxyphenyl ring adjacent to the carbonyl group appeared to benefit the ligand-tubulin interaction, occupying the same subcavity as the corresponding moiety in colchicine. Consistent with modeling predictions, several 3,4,5-trimethoxychalcones showed improved cytotoxicity to murine acute lymphoblastic leukemia cells compared with a previously described parent compound, and inhibited tubulin assembly in vitro as potently as colchicine. The most potent chalcones inhibited the growth of human leukemia cell lines at nanomolar concentrations, caused microtubule destabilization and mitotic arrest in human cervical cancer cells, and inhibited human breast cancer cell migration in scratch wound and Boyden chamber assays.

Asunto(s)

Puntos de Control del Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Chalconas/síntesis química , Chalconas/farmacología , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Chalconas/química , Relación Dosis-Respuesta a Droga , Humanos , Células Jurkat , Ratones , Modelos Químicos , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Células 3T3 NIH , Polimerizacion/efectos de los fármacos , Tubulina (Proteína)/metabolismo

RESUMEN

This study investigated the mechanism of cytotoxicity of octyl (G8) and dodecyl (G12) gallates in a murine melanoma cell line (B16F10). For this purpose, several methods to measure cell viability were used to determine if the cytotoxicity induced by these gallates corresponds to a general or an organelle-specific effect. Furthermore, the mechanisms related to apoptosis were examined, by studying the caspase-3 activity, oxidative stress, mitochondrial potential and the expression of anti- or proapoptotic proteins. When comparing the various methods of assessing cell viability, the tested gallates showed a higher cytotoxicity in the assay that indicates lysosomal activity, compared with the assays that indicate mitochondrial and ribosomal activities. Both gallates promoted the release of lactate dehydrogenase into the medium, indicating an effect on cell membrane integrity. The gallates also promoted cellular oxidative stress, mitochondrial depolarization and an increase in caspase-3 activity. Furthermore, the gallates induced an increase in proapoptotic (Bax) and a decrease in antiapoptotic (Bcl-2) proteins expression. Our results indicate that the apoptotic cell death induced by G8 and G12 in B16F10 cells involves lipid membrane damages, lysosomal and mitochondrial dysfunction, which was accompanied by alterations in apoptotic proteins expression and seems to be triggered by cellular oxidative stress.

Asunto(s)

Apoptosis/efectos de los fármacos , Ácido Gálico/análogos & derivados , Estrés Oxidativo/efectos de los fármacos , Animales , Caspasa 3/metabolismo , Catalasa/metabolismo , Línea Celular Tumoral , Colorantes/metabolismo , ADN/análisis , Ácido Gálico/toxicidad , L-Lactato Deshidrogenasa/metabolismo , Melanoma , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Rojo Neutro/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Receptor fas/metabolismo

RESUMEN

In this study, we investigated the effects of 24 chalcone derivatives from 2-naphthylacetophenone toward a lymphoblastic leukemia cell line (L1210). Three compounds, called R7, R13, and R15, presented concentration- and time-dependent cytotoxicity and induced cellular death by apoptosis via mitochondrial injury and oxidative stress. The effects of these compounds appear to occur through different mechanisms because R13 and R7 induced a greater disturbance of mitochondrial potential, and all compounds induced disturbances of cellular ATP content and increased caspase-3 activity before cellular death. These compounds also interfered with antioxidant enzymes activities and GSH content through different mechanisms.

Asunto(s)

Antineoplásicos/química , Apoptosis , Caspasa 3/metabolismo , Chalcona/análogos & derivados , Chalconas/química , Leucemia/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Estrés Oxidativo , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Línea Celular Tumoral , Chalcona/uso terapéutico , Chalcona/toxicidad , Chalconas/uso terapéutico , Chalconas/toxicidad , Humanos , Especies Reactivas de Oxígeno/metabolismo