RESUMO
Despite the undeniable advances in recent decades, cancer remains one of the deadliest diseases of the current millennium, where the triple-negative breast cancer (TNBC) is very aggressive, extremely metastatic, and resistant to conventional chemotherapy. The nanotheranostic approach focusing on targeting membrane receptors often expressed at abnormal levels by cancer cells can be a strategic weapon for fighting malignant tumors. Herein, we introduced a novel "all-in-one nanosoldier" made of colloidal hybrid nanostructures, which were designed for simultaneously targeting, imaging, and killing TNBC cells. These nanohybrids comprised four distinct components: (a) superparamagnetic iron oxide nanoparticles, as bi-functional nanomaterials for inducing ferroptosis via inorganic nanozyme-mediated catalysis and magnetotherapy by hyperthermia treatment; (b) carboxymethyl cellulose biopolymer, as a water-soluble capping macromolecule; (c) folic acid, as the membranotopic vector for targeting folate receptors; (d) and doxorubicin (DOX) drug for chemotherapy. The results demonstrated that this novel strategy was highly effective for targeting and killing TNBC cells in vitro, expressing high levels of folate membrane-receptors. The results evidenced that three integrated mechanisms triggered the deaths of the cancer cells in vitro: (a) ferroptosis, by magnetite nanoparticles inducing a Fenton-like reaction; (b) magneto-hyperthermia effect by generating heat under an alternate magnetic field; and (c) chemotherapy, through the DOX intracellular release causing DNA dysfunction. This "all-in-one nanosoldier" strategy offers a vast realm of prospective alternatives for attacking cancer cells, combining multimodal therapy and the delivery of therapeutic agents to diseased sites and preserving healthy cells, which is one of the most critical clinical challenges faced in fighting drug-resistant breast cancers.
Assuntos
Antineoplásicos/química , Doxorrubicina/química , Corantes Fluorescentes/química , Nanopartículas de Magnetita/química , Nanocápsulas/química , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/terapia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Terapia Combinada , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Humanos , Hipertermia Induzida/efeitos adversos , Campos Magnéticos , Nanopartículas de Magnetita/uso terapêutico , Terapia de Alvo Molecular , Imagem Óptica , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina TeranósticaRESUMO
Co-encapsulation of anticancer drugs paclitaxel and imatinib in nanocarriers is a promising strategy to optimize cancer treatment. Aiming to combine the cytotoxic and antiangiogenic properties of the drugs, a liposome formulation targeted to folate receptor co-encapsulating paclitaxel and imatinib was designed in this work. An efficient method was optimized for the synthesis of the lipid anchor DSPE-PEG(2000)-folic acid (FA). The structure of the obtained product was confirmed by RMN, FT-IR, and ESI-MS techniques. A new analytical method was developed and validated for simultaneous quantification of the drugs by liquid chromatography. Liposomes, composed of phosphatidylcholine, cholesterol, and DSPE-mPEG(2000), were prepared by extrusion. Their surface was modified by post-insertion of DSPE-PEG(2000)-FA. Reaction yield for DSPE-PEG(2000)-FA synthesis was 87%. Liposomes had a mean diameter of 122.85 ± 1.48 nm and polydispersity index of 0.19 ± 0.01. Lyophilized formulations remained stable for 60 days in terms of size and drug loading. FA-targeted liposomes had a higher effect on MCF7 cell viability reduction (p < 0.05) when compared with non-targeted liposomes and free paclitaxel. On PC-3 cells, viability reduction was greater (p < 0.01) when cells were exposed to targeted vesicles co-encapsulating both drugs, compared with the non-targeted formulation. VEGF gene expression was reduced in MCF7 and PC-3 cells (p < 0.0001), with targeted vesicles exhibiting better performance than non-targeted liposomes. Our results demonstrate that multifunctional liposomes associating molecular targeting and multidrug co-encapsulation are an interesting strategy to achieve enhanced internalization and accumulation of drugs in targeted cells, combining multiple antitumor strategies.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Receptores de Folato com Âncoras de GPI , Mesilato de Imatinib/administração & dosagem , Paclitaxel/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácido Fólico/química , Humanos , Mesilato de Imatinib/farmacologia , Lipossomos , Células MCF-7 , Paclitaxel/farmacologia , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: To determine the influence of the genotype and the level of expression of different enzymes involved in folate metabolism on the response to and toxicity of high-dose methotrexate treatment in pediatric osteosarcomas. STUDY DESIGN: DHFR and Reduced folate carrier 1 (RFC1) semiquantitative expression was analyzed in 34 primary and metastatic osteosarcoma tissues by real-time polymerase chain reaction. The following polymorphisms were also analyzed in peripheral blood from 96 children with osteosarcoma and 110 control subjects: C677T, A1298C (MTHFR), G80A (RFC1), A2756G (MTR), C1420T (SHMT), the 28bp-repeat polymorphism, and 1494del6 of the TYMS gene. Treatment toxicity was scored after each cycle according to criteria from the World Health Organization. RESULTS: DHFR and RFC1 expression was lower in initial osteosarcoma biopsy specimens than in metastases (P = .024 and P = .041, respectively). RFC1 expression was moderately decreased in samples with poor histologic response to preoperative treatment (P = .053). Patients with osteosarcoma with G3/G4 hematologic toxicity were more frequently TT than CT/CC for C677T/MTHFR (P = .023) and GG for A2756G/MTR (P = .048 and P = .057 for gastrointestinal and hematologic toxicity, respectively). CONCLUSIONS: The role of C677T/MTHFR and A2756G/MTR on chemotherapy-induced toxicity should be further investigated in pediatric osteosarcomas receiving high-dose methotrexate. Altered expression of DHFR and RFC1 is a feasible mechanism by which osteosarcoma cells become resistant to methotrexate.
Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Neoplasias Ósseas/tratamento farmacológico , Proteínas de Transporte/genética , Metotrexato/efeitos adversos , Osteossarcoma/tratamento farmacológico , Polimorfismo Genético , Receptores de Superfície Celular/genética , Tetra-Hidrofolato Desidrogenase/genética , Adolescente , Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias Ósseas/genética , Neoplasias Ósseas/mortalidade , Proteínas de Transporte/metabolismo , Estudos de Casos e Controles , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Receptores de Folato com Âncoras de GPI , Ácido Fólico/genética , Ácido Fólico/metabolismo , Gastroenteropatias/induzido quimicamente , Genótipo , Doenças Hematológicas/induzido quimicamente , Humanos , Nefropatias/induzido quimicamente , Masculino , Metotrexato/administração & dosagem , Osteossarcoma/genética , Osteossarcoma/mortalidade , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/metabolismo , Tetra-Hidrofolato Desidrogenase/metabolismoRESUMO
The purpose of the present study was to determine biochemical parameters of folate uptake, and the putative contribution of the membrane-anchored folate receptor in microvillous membrane vesicles obtained from the syncytiotrophoblast of human term placenta. Uptake of [3H]-pteroylglutamic acid (PGA) by microvillous membrane vesicles was pH dependent with a maximum at pH 6.0, and attained equilibrium at 60 min of incubation. Uptake was higher in the presence on an inward pH gradient (pHout = 6.0; pHin = 7.5) than in the absence of the gradient (pHout = pHin = 6.0). The effect of changes in medium osmolality showed that both binding to the vesicular membrane and internalization contributed to the measured [3H]-PGA uptake. Equilibrium uptake experiments using [3H]-PGA concentrations within the physiological range of folate in blood serum showed that saturation was achieved at 30 nM and revealed a single class of binding sites with a Kd of 1.8 nM for [3H]-PGA. Cleavage of the glycosyl-phosphatidylinositol moiety of the folate receptor, which anchors the receptor to the membrane, with phosphatidylinositol-specific phospholipase C resulted in a reduction of about 80% in [3H]-PGA uptake. In conclusion, our results showed that the folate uptake in the maternally facing membrane of the human placenta presents a saturable component and is mediated by the folate receptor to ensure an adequate maternal-fetal folate transfer.