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Reversible electroporation is a suitable technique to aid the internalization of medicaments in cancer tissues without inducing permanent cellular damage, allowing the enhancement of cytotoxic effects without incurring in electric-driven necrotic or apoptotic processes by the presence of non-reversible aqueous pores. An adequate selection of electroporation parameters acquires relevance to reach these goals and avoid opposite effects. This work applies the Method of Fundamental Solutions (MFS) for drug transport simulations in electroporated cancer tissues, using a continuum tumor cord approach and considering both electro-permeabilization and vasoconstriction effects. The MFS algorithm is validated with published results, obtaining satisfactory accuracy and convergence. Then, MFS simulations are executed to study the influence of electric field magnitude [Formula: see text], number of electroporation treatments [Formula: see text], and electroporation time [Formula: see text] on three assessment parameters of electrochemotherapy: the internationalization efficacy accounting for the ability of the therapy to introduce moles into viable cells, cell-kill capacity indicating the faculty to reduce the survival fraction of cancer cells, and distribution uniformity specifying the competence to supply drug homogeneously through the whole tissue domain. According to numerical results, when [Formula: see text] is the reversibility threshold, a positive influence on the first two parameters is only possible once specific values of [Formula: see text] and [Formula: see text] have been exceeded; when [Formula: see text] is just the irreversibility threshold, any combination of [Formula: see text] and [Formula: see text] is beneficial. On the other hand, the drug distribution uniformity is always adversely affected by the application of electric pulses, being this more noticeable as [Formula: see text], [Formula: see text], and [Formula: see text] increases.
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Eletroporação , Neoplasias , Humanos , Eletroporação/métodos , Neoplasias/patologia , Eletricidade , Algoritmos , ApoptoseRESUMO
Public health, production and preservation of food, development of environmentally friendly (cosmeto-)textiles and plastics, synthesis processes using green technology, and improvement of water quality, among other domains, can be controlled with the help of chitosan. It has been demonstrated that this biopolymer exhibits advantageous properties, such as biocompatibility, biodegradability, antimicrobial effect, mucoadhesive properties, film-forming capacity, elicitor of plant defenses, coagulant-flocculant ability, synergistic effect and adjuvant along with other substances and materials. In part, its versatility is attributed to the presence of ionizable and reactive primary amino groups that provide strong chemical interactions with small inorganic and organic substances, macromolecules, ions, and cell membranes/walls. Hence, chitosan has been used either to create new materials or to modify the properties of conventional materials applied on an industrial scale. Considering the relevance of strategic topics around the world, this review integrates recent studies and key background information constructed by different researchers designing chitosan-based materials with potential applications in the aforementioned concerns.
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INTRODUCTION: The handling of antineoplastic drugs should follow strict supervision and safety rules to minimize the occupational exposure risks to professionals involved. The external surface contamination of drug vials is recognized as a health risk. So, our goal was to determine if there is residual contamination on the vials and containers surface of the antineoplastic drugs doxorubicin (DOX) and cyclophosphamide (CP). METHODS: A cross-sectional study was conducted. Samples were collected using a uniform sampling procedure on the inner surfaces of the packages/boxes and the outer surfaces of the vials. The analyzes were executed by high-performance liquid chromatography/mass spectrometry (UHPLC-MS/MS). RESULTS: A total of 209 samples were analyzed, 66 of CP and 143 of DOX. CP levels were detected in nine samples (13.63%), three were below the lower limit of quantification (LLQ) and the other six had contamination levels ranging from 1.24 to 28.04â ng/filter. DOX levels were detected in 36 samples (25.17%), two were below the LLQ and the others had levels between 1.32 and 664.84â ng/filter. The majority of samples with residual contamination were in vials (80.0%), however, boxes also showed contamination. CONCLUSIONS: The results revealed the presence of residual contamination in the vials and packages of CP and DOX drugs. Although the residues found in each sample are small, special care should be taken in the handling and disposal of the antineoplastic drugs. The use of personal protective equipment is fundamental while handling the vials and packaging of cytotoxic drugs.
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Antineoplásicos , Exposição Ocupacional , Humanos , Espectrometria de Massas em Tandem , Estudos Transversais , Antineoplásicos/análise , Ciclofosfamida/análise , Doxorrubicina , Embalagem de Medicamentos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Contaminação de Equipamentos , Monitoramento Ambiental/métodos , Contaminação de Medicamentos/prevenção & controleRESUMO
Melanoma is the most aggressive skin cancer, and its incidence has continued to rise during the past decades. Conventional treatments present severe side effects in cancer patients, and melanoma can be refractory to commonly used anticancer drugs, which justify the efforts to find new potential anti-melanoma drugs. An alternative to promote the discovery of new pharmacological substances would be modifying chemical groups from a bioactive compound. Here we describe the synthesis of seventeen compounds derived from cinnamic acid and their bioactivity evaluation against melanoma cells. The compound phenyl 2,3-dibromo-3-phenylpropanoate (3q) was the most effective against murine B16-F10 cells, as observed in cytotoxicity and cell migration assays. Simultaneously, this compound showed low cytotoxic activity on non-tumor cells. At the highest concentration, the compound 3q was able to trigger apoptosis, whereas, at lower concentrations, it affected the cell cycle and melanoma cell proliferation. Furthermore, cinnamate 3q impaired cell invasion, adhesion, colonization, and actin polymerization. In conclusion, these results highlight the antiproliferative and antimetastatic potential of cinnamic acid derivatives on melanoma.
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Antineoplásicos , Melanoma Experimental , Melanoma , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Cinamatos/química , Cinamatos/farmacologia , Ésteres/farmacologia , Humanos , Melanoma/tratamento farmacológico , Melanoma Experimental/tratamento farmacológico , CamundongosRESUMO
Breast cancer is one of the most lethal types of cancer and a leading cause of mortality among Women worldwide. Citrinin (CIT), a polyketide extracted from the fungus Penicillium citrinum, exhibits a wide range of biological activities such as antibacterial, antifungal, and cytotoxic effects. The aim of the current study was to evaluate the antitumoral effects of CIT against 7,12-dimethylbenzanthracene (DMBA)-induced mammary carcinoma in Swiss mice For this, CIT, DMBA and the standard cyclophosphamide (CPA) induced behavioral changes in experimental animals, and these changes were screened by using the rota rod and open field tests. Additionally, hematological, biochemical, immuno-histochemical, and histopathological analyses were carried out. Results suggest that CIT did not alter behavioral, hematological, and biochemical parameters in mice. DMBA induced invasive mammary carcinoma and showed genotoxic effects in the breasts, bone marrow, lymphocytes, and hepatic cells. It also caused mutagenic effects in the formation of micronuclei, bridges, shoots, and binucleate cells in bone marrow and liver. CIT and CPA genotoxic effects were observed after 3 weeks of therapy, where CIT exhibited a repair capacity and induced significant apoptotic damage in mouse lymphocytes. In conclusion, CIT showed antitumoral effects in Swiss mice, possibly through induction of apoptosis.
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Antineoplásicos/farmacologia , Citrinina/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Penicillium/química , 9,10-Dimetil-1,2-benzantraceno , Animais , Apoptose/efeitos dos fármacos , Ciclofosfamida/farmacologia , Dano ao DNA/efeitos dos fármacos , Feminino , Camundongos , Mutagênicos , Neoplasias Experimentais/químicaRESUMO
Accumulating evidence has been suggesting that combining two or more anticancer drugs can provide additive or synergistic effects, improving therapeutic efficacy and delaying resistance. Nowadays, advances in nanotechnology-based delivery systems have enabled the association of different drugs into a single carrier and provided therapeutic gains to the proposed regimen. However, a new strategy also requires innovative analytical approaches that assess loading capacity, biological performance, and also comprehend the mechanisms of action. Alpha-cyano-4-hydroxycinnamic acid (CHC) and the monoclonal antibody (mAb) cetuximab (CTX) are explored worldwide for their therapeutic benefits against multiple cancer cells. The present work aims to develop and validate a new method for simultaneous quantification of CHC and CTX in nanoparticulate systems by using reverse phase high-performance liquid chromatography (RP-HPLC) with ultraviolet (UV) detection for CHC, and fluorescence detection for CTX. This method was designed following the guidelines of the International Conference on Harmonization ICH Q2 (R1) and the Food and Drug Administration (FDA) - Guidance for Bioanalytical Method Validation. Chromatographic separation was performed on a C18 column with the mobile phase composed by water, 0.1 % (v/v) trifluoroacetic acid (TFA) and acetonitrile (ACN)-0.1 % TFA on gradient mode at a flow rate of 0.6 mL/min. The performance of the present method was evaluated by system suitability; therefore, linearity, accuracy, precision, detection, limit of detection / limit of quantification, and robustness were also highlighted. Specificity was demonstrated by the chromatographic analyses of CHC and CTX, subjected to several informative stress conditions. The developed method was also successfully used for the first time to quantify the CHC and CTX content in poly(lactic-co-glycolic acid)-based nanoparticles. In conclusion, this new and rapid method presented acceptable analytical performance and can be helpful to simultaneously quantify CHC and CTX in future studies applied to anticancer therapy.
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Anticorpos Monoclonais , Nanopartículas , Cetuximab , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos , Limite de DetecçãoRESUMO
A self-nanoemulsifying drug delivery system (SNEDDS) composed of ethyl oleate, Tween 80 and polyethylene glycol 600 was prepared as a new route to improve the efficacy of imatinib. The drug-loaded SNEDDS formed nanodroplets of ethyl oleate stabilized by Tween 80 and polyethylene glycol 600 with a diameter of 81.0±9.5 nm. The nanoemulsion-based delivery system was stable for at least two months, with entrapment efficiency and loading capacity of 16.4±0.1 and 48.3±0.2%, respectively. Imatinib-loaded SNEDDS was evaluated for the drug release profiles, and its effectiveness against MCF-7 cell line was investigated. IC50 values for the imatinib-loaded SNEDDS and an imatinib aqueous solution were 3.1 and 6.5 µg mL-1, respectively.
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Técnicas In Vitro/métodos , Eficácia/classificação , Mesilato de Imatinib/efeitos adversos , Polietilenoglicóis/análise , Concentração Inibidora 50 , Células MCF-7/classificação , Liberação Controlada de Fármacos/efeitos dos fármacosRESUMO
CuO nanostructured thin films supported on silicon with 6.5â¯cm2 area (geometric area greater than the studies reported in the literature) were synthesized by a chemical bath deposition technique. The electrodes were characterized by MEV, XRD, XPS, contact angle, cyclic voltammetry and electrochemical impedance spectroscopy analyses. To evaluate the photoelectrochemical properties of the CuO films, photocurrent-voltage measurements were performed using linear voltammetry. The catalytic activities of CuO nanostructures were evaluated by monitoring photodegradation of Mitoxantrone (MTX) under UV-A light irradiation. The method of photoelectrocatalysis (PEC), applying a voltage of 1.5â¯V and assisted by adding H2O2, was undertaken. To the best of our knowledge, no studies on the degradation of anticancer agents using PEC process have been found in the literature. For comparison purposes, experiments were performed under the same conditions by assisted photocatalysis (PC) with H2O2 and direct photolysis. CuO deposits consist of a needle-like morphology. The presence of CuO in the tenorite phase was evidenced by XRD and the XPS spectra showed the presence of copper(II) oxide. The increase in current under illumination shows that CuO exhibits photoactivity. The PEC system showed a 75% level of MTX degradation, while the level achieved using PC was 50%. Under UV-A light alone only 3% removal was obtained after 180â¯min. Up to 10 by-products were identified by chromatography-mass spectrometry (LC-MS) with m/z values ranging between 521 and 285 and a plausible degradation route has been proposed. It is worth mentioning that 9 by-products identified in this work, were not found in the literature in other studies of degradation or products generated as metabolites. The toxicity tests of MTX before and after PEC treatment with Artemia Salina and Allium cepa showed a decrease in the acute toxicity of the medium as the antineoplastic was degraded.
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Antineoplásicos/química , Cobre/química , Mitoxantrona/química , Nanoestruturas/química , Processos Fotoquímicos , Antineoplásicos/análise , Antineoplásicos/toxicidade , Peróxido de Hidrogênio/química , Mitoxantrona/análise , Mitoxantrona/toxicidade , Modelos QuímicosRESUMO
BACKGROUND: Considerable evidence demonstrates the importance of dithiocarbamates especially disulfiram as anticancer drugs. However there are no systematic reviews outlining how their metal-binding ability is related to their anticancer activity. This review aims to summarize chemical features and metal-binding activity of disulfiram and its metabolite DEDTC, and discuss different mechanisms of action of disulfiram and their contributions to the drug's anticancer activity. METHODS: We undertook a disulfiram-related search on bibliographic databases of peerreviewed research literature, including many historic papers and in vitro, in vivo, preclinical and clinical studies. The selected papers were carefully reviewed and summarized. RESULTS: More than five hundreds of papers were obtained in the initial search and one hundred eighteen (118) papers were included in the review, most of which deal with chemical and biological aspects of Disulfiram and the relationship of its chemical and biological properties. Eighty one (81) papers outline biological aspects of dithiocarbamates, and fifty seven (57) papers report biological activity of Disulfiram as an inhibitor of proteasomes or inhibitor of aldehyde dehydrogenase enzymes, interaction with other anticancer drugs, or mechanism of action related to reactive oxygen species. Other papers reviewed focus on chemical aspects of dithiocarbamates. CONCLUSION: This review confirms the importance of chemical features of compounds such as Disulfiram to their biological activities, and supports repurposing DSF as a potential anticancer agent.
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Antineoplásicos/química , Antineoplásicos/farmacologia , Dissulfiram/química , Dissulfiram/farmacologia , Metais/química , Inibidores de Acetaldeído Desidrogenases/química , Inibidores de Acetaldeído Desidrogenases/farmacologia , Reposicionamento de Medicamentos , Humanos , Neoplasias/tratamento farmacológicoRESUMO
BACKGROUND: The need for therapeutically effective anticancer drug delivery systems constantly persuades researchers to explore novel strategies. OBJECTIVE: In this study a novel cubane based antibacterial nanocomposite was tailored as dual chemotherapy drug delivery vesicle in order to increase the therapeutic outcome in cancer therapy. METHOD: The physico-chemical characterization of engineered nanocarrier was assessed by Fourier transforms infrared spectroscopy (FTIR), Hydrogen nuclear magnetic resonance spectroscopy (1H NMR), Thermogravimetric analysis (TGA), and Field emission scanning electron microscopy-energy dispersive using X-ray (FESEMEDX). The antibacterial activity of novel developed nanocomposite was tested by determining minimum inhibitory concentration (MIC) values against Pseudomonas aeruginosa, Escherichia Coli and Candida albicans. RESULTS: In order to investigate the efficacy of novel engineered nanocomposite (with average particle size of 50 nm) as dual anticancer drug delivery, DOX and MTX were bind to nanocarrier with encapsulation efficiency and loading content of around 97.3 ± 2.7% and 20.8 ± 1.6 %, respectively. Dual drugs released simultaneously with distinct tumor targeted, pH responsive sustained release manner. Moreover, the probable antitumoral activity of this engineered nanocomposite system against MCF7 cell lines was evaluated by MTT assay and cell cycle studies. The outcomes showed that novel engineered nanocomposite had no cytotoxic effects, while DOX@MTX-loaded nanocomposite possessed higher growth inhibition property and higher S-phase arrest as compared to cells treated with DOX@MTX alone. CONCLUSION: It was concluded that this novel cubane based drug delivery vehicle could process antibacterial and anticancer therapeutics spontaneously, representing promising tumor targeted system in nanomedicine.
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Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Metotrexato/farmacologia , Nanocompostos/química , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Candida albicans/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Escherichia coli/efeitos dos fármacos , Humanos , Células MCF-7 , Metotrexato/química , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais CultivadasRESUMO
This review will discuss the contributions of marine natural molecules, a source only recently found to have pharmaceutical prospects, to the development of anticancer drugs. Of the seven clinically utilized compounds with a marine origin, four are used for the treatment of cancer. The development of these drugs has afforded valuable knowledge and crucial insights to meet the most common challenges in this endeavor, such as toxicity and supply. In this context, the development of these compounds will be discussed herein to illustrate, with successful examples provided by cytarabine, trabectedin, eribulin and brentuximab vedotin, the steps involved in this process as well as the scientific advances and technological innovation potential associated with developing a new drug from marine resources.
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Biotecnologia/métodos , Organismos Aquáticos/química , Desenvolvimento de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Oceanos e Mares , Imunoconjugados/uso terapêutico , Imunoconjugados/farmacologia , Imunoconjugados/química , Citarabina/química , Descoberta de Drogas , Trabectedina/química , Furanos/química , Brentuximab Vedotin , Cetonas/química , Antineoplásicos/farmacologia , Antineoplásicos/químicaRESUMO
Lung cancer is the most lethal cancer-related disease worldwide. Since survival rates remain poor, there is an urgent need for more effective therapies that could increase the overall survival of lung cancer patients. Lung tumors exhibit increased levels of oxidative markers with altered levels of antioxidant defenses, and previous studies demonstrated that the overexpression of the antioxidant enzyme catalase (CAT) might control tumor proliferation and aggressiveness. Herein, we evaluated the effect of CAT treatment on the sensitivity of A549 human lung adenocarcinoma cells toward various anticancer treatments, aiming to establish the best drug combination for further therapeutic management of this disease. Exponentially growing A549 cells were treated with CAT alone or in combination with chemotherapeutic drugs (cisplatin, 5-fluorouracil, paclitaxel, daunorubicin, and hydroxyurea). CalcuSyn(®) software was used to assess CAT/drug interactions (synergism or antagonism). Growth inhibition, NFκB activation status, and redox parameters were also evaluated in CAT-treated A549 cells. CAT treatment caused a cytostatic effect, decreased NFκB activation, and modulated the redox parameters evaluated. CAT treatment exhibited a synergistic effect among most of the anticancer drugs tested, which is significantly correlated with an increased H2O2 production. Moreover, CAT combination caused an antagonism in paclitaxel anticancer effect. These data suggest that combining CAT (or CAT analogs) with traditional chemotherapeutic drugs, especially cisplatin, is a promising therapeutic strategy for the treatment of lung cancer.
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Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Catalase/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Dissulfeto de Glutationa/análise , Humanos , Peróxido de Hidrogênio/metabolismo , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Oxirredução , Compostos de Sulfidrila/análiseRESUMO
Polyoxometalates (POMs) are early transition metal oxygen anion clusters. They display interesting biological effects mainly related to their antiviral and antitumor properties. On the other hand, copper compounds also show different biological and pharmacological effects in cell culture and in animal models. We report herein for the first time, a detailed study of the mechanisms of action of a copper(II) compound of the group of HPOMs with the formula K7Na3[Cu4(H2O)2(PW9034)2]20H2O (PW9Cu), in a model of human osteosarcoma derived cell line, MG-63. The compound inhibited selectively the viability of the osteosarcoma cells in the range of 25-100µM (p<0.01). Besides, we have clearly shown a more deleterious action of PW9Cu on tumor osteoblasts than in normal cells. Cytotoxicity studies also showed deleterious effects for PW9Cu. The increment of reactive oxygen species (ROS) and the decrease of the GSH/GSSG ratio were involved in the antiproliferative effects of PW9Cu. Moreover, the compound caused cell cycle arrest in G2 phase, triggering apoptosis as determined by flow cytometry. As a whole, these results showed the main mechanisms of the deleterious effects of PW9Cu in the osteosarcoma cell line MG-63, demonstrating that this compound is a promissory agent for cancer treatments.
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Antineoplásicos/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Complexos de Coordenação/farmacologia , Cobre/farmacologia , Osteossarcoma/tratamento farmacológico , Óxidos/farmacologia , Compostos de Tungstênio/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Cobre/química , Fragmentação do DNA , Glutationa/metabolismo , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Estresse Oxidativo/efeitos dos fármacos , Óxidos/química , Fosfatidilserinas/metabolismo , Compostos de Tungstênio/químicaRESUMO
Microemulsions (MEs) are colloidal systems that can be used for drug-delivery and drug-targeting purposes. These systems are able to incorporate drugs modifying bioavailability and stability and reducing toxic effects. The jasmonate compounds belong to a group of plant stress hormones, and the jasmonic acid and its methyl ester derivative have been described as having anticancer activity. However, these compounds are very poorly water-soluble, not allowing administration by an intravenous route without an efficient nanostructured carrier system. In this work, biocompatible MEs of appropriate diameter size for intravenous route administration, loaded and unloaded with methyl dihydrojasmonate (MJ), were developed and described in a pseudo-ternary phase diagram. The compositions of the MEs were carefully selected from their own regions in the pseudo-ternary phase diagram. The formulations were analyzed by light scattering, polarized light microscopy, and X-ray diffraction. Also, a study on rheological profile was performed. The results showed that the droplet size decreased with both MJ incorporation and oil phase/surfactant ratio. All compositions of the studied MEs showed rheological behavior of pseudoplastic fluid and amorphous structures. In the absence of MJ, most of the studied MEs had thixotropic characteristics, which became antithixotropic in the presence of the drug. Almost all MJ-unloaded MEs presented anisotropic characteristics, but some formulations became isotropic, especially in the presence of MJ. The results of this study support the conclusion that the studied system represents a promising vehicle for in vivo administration of the MJ antitumor drug.
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Antineoplásicos/administração & dosagem , Ciclopentanos/administração & dosagem , Sistemas de Liberação de Medicamentos , Materiais Biocompatíveis/química , Química Farmacêutica , Coloides , Emulsões , Humanos , Nanomedicina , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Óleos , Reologia , Solubilidade , ÁguaRESUMO
A Beta-lapachona tem inspirado uma série de trabalhos científicos, tendo em vista os inúmeros estudos farmacológicos relatados na literatura, que comprovam suas atividades antibacteriana, antifúngica, antitripanossômica, antiviral, anti-inflamatória e antineoplásica. Devido a sua potente atividade anticancerígena, este fármaco encontra-se, atualmente, em estudo clínico de fase II para o tratamento de câncer pancreático. O objetivo deste estudo foi determinar as propriedades físico-químicas deste ativo com o emprego de diversas ferramentas analíticas, como, difração de Raios X, infravermelho, análises térmicas, microscopia eletrônica de varredura e ensaio de dissolução. Os resultados obtidos na difração de raios X revelaram o padrão policristalino do fármaco; o infravermelho identificou os principais grupos funcionais da Beta-lapachona; os dados das análises térmicas apresentaram características de um produto cristalino e de alta pureza; a eletromicrografia demonstrou sua forma cristalina, como cristais acidulares bem definidos de tamanho regular, corroborando com os dados do difratograma. No estudo de dissolução comprovamos que a Beta-lapachona é praticamente insolúvel em água, sendo necessário o desenvolvimento de estratégias tecnológicas destinadas a melhorar a sua solubilidade em meio aquoso. Dessa forma, a determinação das principais características físico-químicas da Beta-lapachona será extremamente útil na identificação de problemas que possam vir a surgir durante a formulação e auxiliará no desenvolvimento de formas farmacêuticas mais eficazes e com qualidade.
A series of scientific papers on Beta-lapachone has been inspired by the numerous pharmacological reports in the literature that demonstrate its antibacterial, antifungal, antitrypanosomal, antiviral, anticancer and anti-inflammatory activities. Owing to its potent anticancer activity, this drug is currently undergoing phase II clinical trials for the treatment of pancreatic cancer. The aim of this study was to determine the physicochemical properties of this drug by means of several analytical tools, such as X-ray diffraction (XRD), infrared (IR) spectroscopy, thermal analysis, scanning electron microscopy (SEM) and dissolution test. The XRD patterns showed the polycrystalline state of the drug; IR spectroscopy identified the main functional groups of Beta-lapachone; the data from thermal analysis showed characteristics of a crystalline product of high purity and the SEM micrographs showed the crystalline form as well-defined acidulated crystals of regular size, corroborating the XRD patterns. In the dissolution test we found that Beta-lapachone is practically insoluble in water, necessitating the development of technological strategies to improve its solubility in aqueous media. Thus, the determination of the main physicochemical characteristics of Beta-lapachone will be extremely useful in identifying problems that may arise during the design and in the development of more effective and higher quality pharmaceutical forms of this drug.
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Antineoplásicos/antagonistas & inibidores , TabebuiaRESUMO
Pituitary tumor-transforming gene-1 (PTTG1) is a proto-oncogene that promotes tumorigenesis and metastasis in numerous cell types and is overexpressed in a variety of human tumors. We have demonstrated that PTTG1 expression was up-regulated in both human prostate cancer specimens and prostate cancer cell lines. For a more direct assessment of the function of PTTG1 in prostate tumorigenesis, RNAi-mediated knockdown was used to selectively decrease PTTG1 expression in PC3 human prostate tumor cells. After three weeks of selection, colonies stably transfected with PTTG1-targeted RNAi (the knockdown PC3 cell line) or empty vector (the control PC3 cell line) were selected and expanded to investigate the role of PTTG1 expression in PC3 cell growth and invasion. Cell proliferation rate was significantly slower (28%) in the PTTG1 knockdown line after 6 days of growth as indicated by an MTT cell viability assay (P < 0.05). Similarly, a soft agar colony formation assay revealed significantly fewer (66.7%) PTTG1 knockdown PC3 cell colonies than control colonies after three weeks of growth. In addition, PTTG1 knockdown resulted in cell cycle arrest at G1 as indicated by fluorescence-activated cell sorting. The PTTG1 knockdown PC3 cell line also exhibited significantly reduced migration through Matrigel in a transwell assay of invasive potential, and down-regulation of PTTG1 could lead to increased sensitivity of these prostate cancer cells to a commonly used anticancer drug, taxol. Thus, PTTG1 expression is crucial for PC3 cell proliferation and invasion, and could be a promising new target for prostate cancer therapy.