Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Int J Nanomedicine ; 19: 1843-1865, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414530

RESUMO

Purpose: The lack of specificity of conventional chemotherapy is one of the main difficulties to be solved in cancer therapy. Biomimetic magnetoliposomes are successful chemotherapy controlled-release systems, hyperthermia, and active targeting agents by functionalization of their surface with monoclonal antibodies. The membrane receptor Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5) stands out as colorectal cancer (CRC) biomarker and appears to be related to treatment resistance and the development of metastasis. The aim of this study was to assess the effectiveness and safety of LGR5-targeted biomimetic magnetoliposomes loaded with oxaliplatin (OXA) or 5-fluorouracil (5-FU) in the selective treatment of CRC and their possible application in hyperthermia. Methods: Synthesis, characterization and determination of heating capacity of magnetoliposomes transporting OXA or 5-FU (with and without LGR5 functionalization) were conducted. In vitro antitumoral activity was assayed in multiple colorectal cell lines at different times of exposition. In addition to this, cell internalization was studied by Prussian Blue staining, flow cytometry and fluorescence microscopy. In vivo acute toxicity of magnetoliposomes was performed to evaluate iron-related toxicity. Results: OXA and 5-FU loaded magnetoliposomes functionalized with LGR5 antibody showed higher cellular uptake than non-targeted nanoformulation with a reduction of the percentage of proliferation in colon cancer cell lines up to 3.2-fold of the IC50 value compared to that of free drug. The differences between non-targeted and targeted nanoformulations were more evident after short exposure times (4 and 8 hours). Interestingly, assays in the MC38 transduced cells with reduced LGR5 expression (MC38-L(-)), showed lower cell internalization of LGR5-targeted magnetoliposomes compared to non-transduced MC38 cell line. In addition, magnetoliposomes showed an in vitro favorable heating response under magnetic excitation and great iron-related biocompatibility data in vivo. Conclusion: Drug-loaded magnetoliposomes functionalized with anti-LGR5 antibodies could be a promising CRC treatment strategy for LGR5+ targeted chemotherapy, magnetic hyperthermia, and both in combination.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Hipertermia Induzida , Humanos , Biomimética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Fluoruracila/uso terapêutico , Oxaliplatina/uso terapêutico , Ferro , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-38078737

RESUMO

Recently, the classical anatomy of the quadriceps femoris has been questioned after the publication of various morphological variations that differ from the classical description. Therefore, it is necessary to collect information to reach an agreement on its structure. For this, a systematic review was carried out using the Web of Science, Pubmed and ProQuest scientific databases, obtaining a total of 29 papers finally included in the systematic review after being subjected to inclusion and exclusion criteria. The results obtained showed an important and variable prevalence of new configurations described, such as additional heads in the rectus femoris, a different origin of the vastus intermedius, various portions of the vastus lateralis, or the involvement of the vastus medialis in the patellofemoral musculature. For this reason, understanding the anatomy of the quadriceps femoris is a matter that has not yet been fully resolved, with high variability among people that must be studied prior to the application of an invasive and/or surgical procedure.

3.
Eur J Pharm Biopharm ; 193: 241-253, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972906

RESUMO

Among the most harmful tumors detected in the human body, such as breast, colon, brain or pancreas, breast (BC) and colorectal cancer (CRC) are the first and third most frequent cancer worldwide, respectively. The current existing chemotherapeutic treatments present serious side effects due to their intravenous administration can induce cytotoxicity in healthy cells. Thus, new treatment methods based on drug-loaded polymeric nanofibers (NFs) have gained significant potential for their use in localized cancer chemotherapy. Here, a deep in vitro comparative analysis between maslinic acid (MA) and a tyramine-maslinic acid (TMA) derivative is initially performed. This analysis includes a proliferation, and a cell cycle assay, and a genotoxicity, antiangiogenic and apoptosis study. Then, the TMA derivative has been incorporated into electrospun polymeric NFs obtaining an implantable dressing material with antitumor activity. Two types of patches containing TMA-loaded polymeric NFs of poly(caprolactone) (PCL), and a mixture of polylactic acid/poly(4-vinylpyridine) (PLA/PVP) were fabricated by the electrospinning technique. The characterization of the drug-loaded NFs showed an encapsulation capacity of 0.027 mg TMA/mg PCL and 0.024 mg TMA/mg PLA/PVP. Then, the cytotoxic activity of both polymeric systems was tested in CRC (T84), BC (MCF-7) and a no tumor (L929) cell lines exposed to TMA-loaded NFs and blank NFs for 48 h. Moreover, cell cycle assay, genotoxicity, angiogenesis and apoptosis tests were carried out to study the mechanism of action of TMA. Blank NFs showed no-toxicity in all cell lines tested and both drug-loaded NFs significantly reduced cell proliferation (relative proliferation of ≈44 % and ≈25 % respectively). Therefore, TMA was less genotoxic than maslinic acid (MA), and reduced VEGFA expression in MCF-7 cells (1.32 and 2.12-fold for MA and TMA respectively). These results showed that TMA-loaded NFs could constitute a promising biocompatible and biodegradable nanoplatform for the local treatment of solid tumors such as CRC or BC.


Assuntos
Nanofibras , Neoplasias , Humanos , Preparações Farmacêuticas , Polímeros , Poliésteres
4.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37511009

RESUMO

Anemonia sulcata may be a source of marine natural products (MNPs) due to the antioxidant and antitumor activity of its crude homogenates shown in vitro in colon cancer cells. A bioguided chromatographic fractionation assay of crude Anemonia sulcata homogenates with and without its symbiont Symbiodinium was performed to characterize their bioactive composition and further determine their biological potential for the management of colorectal cancer (CRC). The 20% fractions retained the in vitro antioxidant activity previously reported for homogenates. As such, activation of antioxidant and detoxifying enzymes was also evaluated. The 40% fractions showed the greatest antiproliferative activity in T84 cells, synergistic effects with 5-fluoruracil and oxaliplatin, overexpression of apoptosis-related proteins, cytotoxicity on tumorspheres, and antiangiogenic activity. The predominantly polar lipids and toxins tentatively identified in the 20% and 40% fractions could be related to their biological activity in colon cancer cells although further characterizations of the active fractions are necessary to isolate and purify the bioactive compounds.


Assuntos
Neoplasias Colorretais , Anêmonas-do-Mar , Animais , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Cromatografia , Neoplasias Colorretais/tratamento farmacológico
5.
Pharmaceutics ; 15(7)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37514144

RESUMO

The incidence of gastrointestinal cancers has increased in recent years. Current treatments present numerous challenges, including drug resistance, non-specificity, and severe side effects, needing the exploration of new therapeutic strategies. One promising avenue is the use of magnetic nanoparticles, which have gained considerable interest due to their ability to generate heat in tumor regions upon the application of an external alternating magnetic field, a process known as hyperthermia. This review conducted a systematic search of in vitro and in vivo studies published in the last decade that employ hyperthermia therapy mediated by magnetic nanoparticles for treating gastrointestinal cancers. After applying various inclusion and exclusion criteria (studies in the last 10 years where hyperthermia using alternative magnetic field is applied), a total of 40 articles were analyzed. The results revealed that iron oxide is the preferred material for magnetism generation in the nanoparticles, and colorectal cancer is the most studied gastrointestinal cancer. Interestingly, novel therapies employing nanoparticles loaded with chemotherapeutic drugs in combination with magnetic hyperthermia demonstrated an excellent antitumor effect. In conclusion, hyperthermia treatments mediated by magnetic nanoparticles appear to be an effective approach for the treatment of gastrointestinal cancers, offering advantages over traditional therapies.

6.
Life (Basel) ; 12(11)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36362920

RESUMO

The emergence of resistance to pancreatic cancer (PC) current treatment requires the development of new therapeutic strategies. In this context, bioactive molecules from plant extracts have shown excellent properties to improve classical therapy against this type of tumor. This systematic review aims to collect all the in vitro studies related to the antiproliferative activity of isolated plant molecules that support their applicability in PC. A total of 620 articles published in the last 10 years were identified, although only 28 were finally included to meet the inclusion criteria. Our results reflect the most important biomolecules from natural compounds that induce cell death in PC and their essential mechanism of cell death, including apoptosis, pathways activated by the KRAS mutation and cycle cell arrest, among others. These in vitro studies provide an excellent molecule guide showing applications against PC and that should be tested in vivo and in clinical trials to determine their usefulness to reduce PC incidence and to improve the prognosis of these patients. However, natural compounds are isolated in small amounts, which prevents comprehensive drug screening, being necessary the role of organic synthesis for the total synthesis of natural compounds or for the synthesis of their simplified and bioactive analogs.

7.
Int J Nanomedicine ; 17: 5065-5080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36345508

RESUMO

The failure of chemotherapeutic treatment in colorectal cancer (CRC), the second most mortal cancer worldwide, is associated with several drug limitations, such as non-selective distribution, short half-life, and development of multiple resistances. One of the most promising strategies in CRC therapy is the development of delivery systems based on nanomaterials that can transport antitumor agents to the tumor site more efficiently, increasing accumulation within the tumor and thus the antitumor effect. In addition to taking advantage of the increased permeability and retention effect (EPR) of solid tumors, these nanoformulations can be conjugated with monoclonal antibodies that recognize molecular markers that are specifically over-expressed on CRC cells. Active targeting of nanoformulations reduces the adverse effects associated with the cytotoxic activity of drugs in healthy tissues, which will be of interest for improving the quality of life of cancer patients in the future. This review focuses on in vitro and in vivo studies of drug delivery nanoformulations functionalized with monoclonal antibodies for targeted therapy of CRC.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Humanos , Qualidade de Vida , Sistemas de Liberação de Medicamentos , Antineoplásicos/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia
8.
Mar Drugs ; 20(5)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35621969

RESUMO

Nannochloropsis gaditana is a microalga with interesting nutritional and functional value due to its high content of protein, polyunsaturated fatty acids, and bioactive compounds. However, the hardness of its cell wall prevents accessibility to these components. This work aimed to study the effect of a treatment to increase the fragility of the cell wall on the bioavailability of its nutrients and functional compounds. The antioxidant and antiproliferative capacity of functional extracts from treated and untreated N. gaditana was assessed, and the profile of bioactive compounds was characterized. Furthermore, to study the effect of treatment on its nutrient availability and functional capacity, an in vivo experiment was carried out using a rat experimental model and a 20% dietary inclusion level of microalgae. Functional extracts from treated N. gaditana exhibited higher antioxidant activity than the untreated control. Furthermore, the treated microalga induced hypoglycemic action, higher nitrogen digestibility, and increased hepatic antioxidant activity. In conclusion, N. gaditana has interesting hepatoprotective, antioxidant, and anti-inflammatory potential, thus proving itself an ideal functional food candidate, especially if the microalga is treated to increase the fragility of its cell wall before consumption.


Assuntos
Microalgas , Estramenópilas , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Microalgas/metabolismo , Avaliação Nutricional , Ratos , Estramenópilas/metabolismo
9.
Bioimpacts ; 12(6): 515-531, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36644541

RESUMO

Introduction: Paclitaxel (PTX) is a cornerstone in the treatment of breast cancer, the most common type of cancer in women. However, this drug has serious limitations, including lack of tissue-specificity, poor water solubility, and the development of drug resistance. The transport of PTX in a polymeric nanoformulation could overcome these limitations. Methods: In this study, PLGA-PTX nanoparticles (NPs) were assayed in breast cancer cell lines, breast cancer stem cells (CSCs) and multicellular tumor spheroids (MTSs) analyzing cell cycle, cell uptake (Nile Red-NR-) and α-tubulin expression. In addition, PLGA-PTX NPs were tested in vivo using C57BL/6 mice, including a biodistribution assay. Results: PTX-PLGA NPs induced a significant decrease in the PTX IC50 of cancer cell lines (1.31 and 3.03-fold reduction in MDA-MB-231 and E0771 cells, respectively) and CSCs. In addition, MTSs treated with PTX-PLGA exhibited a more disorganized surface and significantly higher cell death rates compared to free PTX (27.9% and 16.3% less in MTSs from MCF-7 and E0771, respectively). PTX-PLGA nanoformulation preserved PTX's mechanism of action and increased its cell internalization. Interestingly, PTX-PLGA NPs not only reduced the tumor volume of treated mice but also increased the antineoplastic drug accumulation in their lungs, liver, and spleen. In addition, mice treated with PTX-loaded NPs showed blood parameters similar to the control mice, in contrast with free PTX. Conclusion: These results suggest that our PTX-PLGA NPs could be a suitable strategy for breast cancer therapy, improving antitumor drug efficiency and reducing systemic toxicity without altering its mechanism of action.

10.
Pharmaceuticals (Basel) ; 16(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36678519

RESUMO

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Despite the advances and success of current treatments (e.g., chemotherapy), there are multiple serious side effects which require the development of new treatment strategies. In recent years, fungi have gained considerable attention as a source of extracts and bioactive compounds with antitumor capabilities because of their antimicrobial and antioxidant properties and even their anti-inflammatory and antiviral activities. In the present review, a systematic search of the existing literature in four electronic databases was carried out in which the antitumor activity against CRC cells of Ascomycota fungi extracts or compounds was tested. The systematical research in the four databases resulted in a total of 883 articles. After applying exclusion and inclusion criteria, a total of 75 articles were finally studied. The order Eurotiales was the most studied (46% of the articles), and the ethyl acetate extraction was the most used method (49% of the papers). Penicillium extracts and gliotoxin and acetylgliotoxin G bioactive compounds showed the highest cytotoxic activity. This review also focuses on the action mechanisms of the extracts and bioactive compounds of fungi against CRC, which were mediated by apoptosis induction and the arrest of the cell cycle, which induces a notable reduction in the CRC cell proliferation capacity, and by the reduction in cell migration that limits their ability to produce metastasis. Thus, the ability of fungi to induce the death of cancer cells through different mechanisms may be the basis for the development of new therapies that improve the current results, especially in the more advanced stages of the CCR.

11.
Cancers (Basel) ; 13(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34201986

RESUMO

Sodium selenite acts by depleting enzymes that protect against cellular oxidative stress. To determine its effect alone or in combination with gemcitabine (GMZ) in pancreatic cancer, we used PANC-1 and Pan02 cell lines and C57BL mice bearing a Pan02-generated tumor. Our results demonstrated a significant inhibition of pancreatic cancer cell viability with the use of sodium selenite alone and a synergistic effect when associated with GMZ. The molecular mechanisms of the antitumor effect of sodium selenite alone involved apoptosis-inducing factor (AIF) and the expression of phospho-p38 in the combined therapy. In addition, sodium selenite alone and in association with GMZ significantly decreased the migration capacity and colony-forming ability, reduced tumor activity in multicellular tumor spheroids (MTS) and decreased sphere formation of cancer stem cells. In vivo studies demonstrated that combined therapy not only inhibited tumor growth (65%) compared to the untreated group but also relative to sodium selenite or GMZ used as monotherapy (up to 40%), increasing mice survival. These results were supported by the analysis of C57BL/6 albino mice bearing a Pan02-generated tumor, using the IVIS system. In conclusion, our results showed that sodium selenite is a potential agent for the improvement in the treatment of pancreatic cancer and should be considered for future human clinical trials.

12.
Cancers (Basel) ; 13(9)2021 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-33923200

RESUMO

The development of drug resistance is one of the main causes of cancer treatment failure. This phenomenon occurs very frequently in different types of cancer, including colon and pancreatic cancers. However, the underlying molecular mechanisms are not fully understood. In recent years, nanomedicine has improved the delivery and efficacy of drugs, and has decreased their side effects. In addition, it has allowed to design drugs capable of avoiding certain resistance mechanisms of tumors. In this article, we review the main resistance mechanisms in colon and pancreatic cancers, along with the most relevant strategies offered by nanodrugs to overcome this obstacle. These strategies include the inhibition of efflux pumps, the use of specific targets, the development of nanomedicines affecting the environment of cancer-specific tissues, the modulation of DNA repair mechanisms or RNA (miRNA), and specific approaches to damage cancer stem cells, among others. This review aims to illustrate how advanced nanoformulations, including polymeric conjugates, micelles, dendrimers, liposomes, metallic and carbon-based nanoparticles, are allowing to overcome one of the main limitations in the treatment of colon and pancreatic cancers. The future development of nanomedicine opens new horizons for cancer treatment.

13.
Biology (Basel) ; 10(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567702

RESUMO

Recently, invertebrate marine species have been investigated for the presence of natural products with antitumor activity. We analyzed the invertebrate Anemonia sulcata with (W) and without (W/O) the presence of its microalgal symbiont Symbiodinium as a source of bioactive compounds that may be applied in the therapy and/or prevention of colorectal cancer (CRC). Animals were mechanically homogenized and subjected to ethanolic extraction. The proximate composition and fatty acid profile were determined. In addition, an in vitro digestion was performed to study the potentially dialyzable fraction. The antioxidant and antitumor activity of the samples and the digestion products were analyzed in CRC cells in vitro. Our results show a high concentration of polyunsaturated fatty acid in the anemone and a great antioxidant capacity, which demonstrated the ability to prevent cell death and a high antitumor activity of the crude homogenates against CRC cells and multicellular tumor spheroids, especially W/O symbiont. These preliminary results support that Anemonia sulcata could be a source of bioactive compounds with antioxidant and antitumor potential against CRC and that the absence of its symbiont may enhance these properties. Further studies will be necessary to define the bioactive compounds of Anemonia sulcata and their mechanisms of action.

14.
Nutrients ; 13(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572111

RESUMO

The seeds of Euphorbia lathyris have been used in traditional medicine to treat various medical conditions. However, neither all of their active biocompounds nor the molecular mechanisms underlying their therapeutic effects have been described. A new ethanolic extract of defatted flour from mature seeds of Euphorbia lathyris showed a high total polyphenol content and significant antioxidant activity. Chromatographic analysis showed that esculetin, euphorbetin, gaultherin, and kaempferol-3-rutinoside were the most abundant polyphenolic bioactive compounds. Antiproliferative assays showed a high and selective antitumor activity against colon cancer cell lines (T84 and HCT-15). In addition, a significant antiproliferative activity against glioblastoma multiforme cells was also demonstrated. Its mechanism of action to induce cell death was mediated by the overexpression of caspases 9, 3, and 8, and by activation of autophagy. Interestingly, a reduction in the migration capacity of colon cancer cells and a significant antiangiogenic effect on human umbilical vein endothelial cells were also demonstrated. Finally, the extract significantly reduced the subpopulations of cancer stem cells. This extract could be the basis to develop new therapeutic strategies for the treatment of colon cancer, although further experiments will be necessary to determine its in vivo effects.


Assuntos
Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/patologia , Euphorbia/química , Extratos Vegetais/farmacologia , Sementes/química , Adenocarcinoma/patologia , Antineoplásicos Fitogênicos , Antioxidantes/análise , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Etanol , Glioblastoma/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Polifenóis/análise
15.
Curr Neuropharmacol ; 19(4): 513-537, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32589560

RESUMO

Temozolomide (TMZ), an oral alkylating prodrug which delivers a methyl group to purine bases of DNA (O6-guanine; N7-guanine and N3-adenine), is frequently used together with radiotherapy as part of the first-line treatment of high-grade gliomas. The main advantages are its high oral bioavailability (almost 100% although the concentration found in the cerebrospinal fluid was approximately 20% of the plasma concentration of TMZ), its lipophilic properties, and small size that confer the ability to cross the blood-brain barrier. Furthermore, this agent has demonstrated activity not only in brain tumors but also in a variety of solid tumors. However, conventional therapy using surgery, radiation, and TMZ in glioblastoma results in a median patient survival of 14.6 months. Treatment failure has been associated with tumor drug resistance. This phenomenon has been linked to the expression of O6-methylguanine-DNA methyltransferase, but the mismatch repair system and the presence of cancer stem-like cells in tumors have also been related to TMZ resistance. The understanding of these mechanisms is essential for the development of new therapeutic strategies in the clinical use of TMZ, including the use of nanomaterial delivery systems and the association with other chemotherapy agents. The aim of this review is to summarize the resistance mechanisms of TMZ and the current advances to improve its clinical use.


Assuntos
Nanotecnologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico
16.
Biomed Pharmacother ; 133: 111059, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33378963

RESUMO

Paclitaxel (PTX), a drug widely used in lung cancer, has serious limitations including the development of peripheral neurotoxicity, which may lead to treatment discontinuation and therapy failure. The transport of PTX in large cationic liposomes could avoid this undesirable effect, improving the patient's prognosis. PTX was encapsulated in cationic liposomes with two different sizes, MLV (180-200 nm) and SUV (80-100 nm). In both cases, excellent biocompatibility and improved internalization and antitumor effect of PTX were observed in human and mice lung cancer cells in culture, multicellular spheroids and cancer stem cells (CSCs). In addition, both MLV and SUV with a polyethylene glycol (PEG) shell, induced a greater tumor volume reduction than PTX (56.4 % and 57.1 % vs. 36.7 %, respectively) in mice. Interestingly, MLV-PEG-PTX did not induce either mechanical or heat hypersensitivity whereas SUV-PEG-PTX produced a similar response to free PTX. Analysis of PTX distribution showed a very low concentration of the drug in the dorsal root ganglia (DRG) with MLV-PEG-PTX, but not with SUV-PEG-PTX or free PTX. These results support the hypothesis that PTX induces peripheral neuropathy by penetrating the endothelial fenestrations of the DRG (80-100 nm, measured in mice). In conclusion, our larger liposomes (MLV-PEG-PTX) not only showed biocompatibility, antitumor activity against CSCs, and in vitro and in vivo antitumor effect that improved PTX free activity, but also protected from PTX-induced painful peripheral neuropathy. These advantages could be used as a new strategy of lung cancer chemotherapy to increase the PTX activity and reduce its side effects.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Lipídeos/química , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/administração & dosagem , Polietilenoglicóis/química , Células A549 , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/toxicidade , Cátions , Proliferação de Células/efeitos dos fármacos , Composição de Medicamentos , Feminino , Gânglios Espinais/efeitos dos fármacos , Humanos , Lipossomos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Paclitaxel/química , Paclitaxel/farmacocinética , Paclitaxel/toxicidade , Tamanho da Partícula , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Carga Tumoral
17.
Polymers (Basel) ; 12(12)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255803

RESUMO

A reproducible and efficient interfacial polymer disposition method has been used to formulate magnetite/poly(ε-caprolactone) (core/shell) nanoparticles (average size ≈ 125 nm, production performance ≈ 90%). To demonstrate that the iron oxide nuclei were satisfactorily embedded within the polymeric solid matrix, a complete analysis of these nanocomposites by, e.g., electron microscopy visualizations, energy dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, electrophoresis, and contact angle goniometry was conducted. The magnetic responsive behaviour of these nanoparticles was quantitatively characterized by the hysteresis cycle and qualitatively investigated by visualization of the colloid under exposure to a 0.4 T magnet. Gemcitabine entrapment into the polymeric shell reported adequate drug loading values (≈11%), and a biphasic and pH-responsive drug release profile (≈ four-fold faster Gemcitabine release at pH 5.0 compared to pH 7.4). Cytotoxicity studies in MCF-7 human breast cancer cells proved that the half maximal inhibitory concentration of Gem-loaded nanocomposites was ≈ two-fold less than that of the free drug. Therefore, these core/shell nanoparticles could have great possibilities as a magnetically targeted Gemcitabine delivery system for breast cancer treatment.

18.
J Biosci ; 452020.
Artigo em Inglês | MEDLINE | ID: mdl-33097678

RESUMO

Cancer stem cells (CSCs) from colorectal cancer (CRC), characterized by CD133 expression, have been associated with 5-fluorouracile (5-FU) chemoresistance. DNA repair mechanisms, such as O6-alkylguanine DNA alkyltransferase (MGMT) and mismatch repair (MMR) systems, have also been correlated to 5-FU resistance in CRC. The aim of this study was to evaluate the modulation of CD133 and MGMT in MMRproficient and MMR-deficient CRC cells under 5-FU treatment and the effect of this drug in CSCs. CD133 and MGMT methylation status were determined in MMR-proficient (SW480 and HT29) and MMR-deficient (RKO and HCT116) cell lines by methylation-specific PCRs. SW480 and RKO were selected to determine modulation of CD133, MGMT and MMR expression after 5-FU treatment by qPCR. In addition, CD133, MGMT and MMR were analyze in SW480 and RKO CSCs. No association between promoter methylation and MGMT and CD133 expression was found. 5-FU treatment increased CD133 expression independently to MMR status in SW480 and RKO and was able to increase hMLH1 expression in RKO, a MMR-deficient cell line. RKO/ CSCs overexpressed CD133 and MMR (hMSH2 and hMSH6) while SW480/CSCs showed a significant increase in CD133, MMR (hMLH1, hMSH2 and hMSH6) and MGMT, moreover 5-FU resistance than parental cell lines. Thus, although CSCs 5-FU chemoresistance appears to be independently to MMR status, hMLH1 might play a key role in CSC response to 5-FU. New drugs exploding these differences could benefit the prognostic of patients with CRC.


Assuntos
Antígeno AC133/genética , Neoplasias Colorretais/tratamento farmacológico , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Proteína 1 Homóloga a MutL/genética , Proteínas Supressoras de Tumor/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Metilação de DNA/efeitos dos fármacos , Reparo de Erro de Pareamento de DNA/genética , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Proteína 2 Homóloga a MutS/genética , Células-Tronco Neoplásicas/efeitos dos fármacos
19.
J Control Release ; 327: 296-315, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32814093

RESUMO

Extracellular vesicles (EVs) are lipid bilayer vesicles of nanometric size secreted by cells to communicate with other cells, either nearby or remotely. Their physicochemical properties make them a promising nanomedicine for drug transport and release in cancer therapy. In this review, we present the different types and biogenesis of EVs and highlight the importance of adequately selecting the cell of origin in cancer therapy. Furthermore, the main methodologies followed for the isolation of EVs and drug loading, as well as the modification and functionalization of these vesicles to generate EV-based nanocarriers are discussed. Finally, we review some of the main studies using drug-loaded exosomes in tumor therapy both in in vitro and in vivo models (even in resistant tumors). These investigations show promising results, achieving significant improvement in the antitumor effect of drugs in most cases. However, the number of clinical trials and patents based on these nanoformulations is still low, thus further research is still warranted in this area.


Assuntos
Vesículas Extracelulares , Neoplasias , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Humanos , Nanomedicina , Neoplasias/tratamento farmacológico
20.
Pharmaceutics ; 12(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599905

RESUMO

Current chemotherapy for colorectal cancer (CRC) includes the use of oxaliplatin (Oxa), a first-line cytotoxic drug which, in combination with irinotecan/5-fluorouracil or biologic agents, increases the survival rate of patients. However, the administration of this drug induces side effects that limit its application in patients, making it necessary to develop new tools for targeted chemotherapy. MamC-mediated biomimetic magnetic nanoparticles coupled with Oxa (Oxa-BMNPs) have been previously demonstrated to efficiently reduce the IC50 compared to that of soluble Oxa. However, their strong interaction with the macrophages revealed toxicity and possibility of aggregation. In this scenario, a further improvement of this nanoassembly was necessary. In the present study, Oxa-BMNPs nanoassemblies were enveloped in phosphatidylcholine unilamellar liposomes (both pegylated and non-pegylated). Our results demonstrate that the addition of both a lipid cover and further pegylation improves the biocompatibility and cellular uptake of the Oxa-BMNPs nanoassemblies without significantly reducing their cytotoxic activity in colon cancer cells. In particular, with the pegylated magnetoliposome nanoformulation (a) hemolysis was reduced from 5% to 2%, being now hematocompatibles, (b) red blood cell agglutination was reduced, (c) toxicity in white blood cells was eliminated. This study represents a truly stepforward in this area as describes the production of one of the very few existing nanoformulations that could be used for a local chemotherapy to treat CRC.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...