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1.
J Mater Chem B ; 11(1): 169-179, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36484323

RESUMEN

The search for efficient heavy atom free photosensitizers (PSs) for photodynamic therapy (PDT) is a very active field. We describe herein a simple and easily accessible molecular design based on the attachment of an enamine group as an electron-donor moiety at the meso position of the BODIPY core with different alkylation patterns. The effect of the alkylation degree and solvent polarity on the photophysical properties in terms of splitting absorption bands, fluorescence efficiencies and singlet oxygen production is analyzed in depth experimentally using spectroscopic techniques, including femtosecond and nanosecond transient absorption (fs- and ns-TA) and using computational simulations based on time-dependent density functional theory. The correlation between the theoretical/experimental results permits the rationalization of the observed photophysical behavior exhibited by meso-enamine-BODIPY compounds and the determination of mechanistic details, which rule the population of the triplet state manifold. The potential applicability as a theragnostic agent for the most promising compound is demonstrated through in vitro assays in HeLa cells by analyzing the internalization, localization and phototoxic action.


Asunto(s)
Fotoquimioterapia , Fármacos Fotosensibilizantes , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Células HeLa , Halógenos
2.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36361615

RESUMEN

The enhancement of photodynamic therapy (PDT) effectiveness by combining it with other treatment modalities and improved drug delivery has become an interesting field in cancer research. We have prepared and characterized nanoliposomes containing the chemotherapeutic drug irinotecan (CPT11lip), the photodynamic agent protoporphyrin IX (PpIXlip), or their combination (CPT11-PpIXlip). The effects of individual and bimodal (chemo-phototherapeutic) treatments on HeLa cells have been studied by a combination of biological and photophysical studies. Bimodal treatments show synergistic cytotoxic effects on HeLa cells at relatively low doses of PpIX/PDT and CPT11. Mechanistic cell inactivation studies revealed mitotic catastrophe, apoptosis, and senescence contributions. The enhanced anticancer activity is due to a sustained generation of reactive oxygen species, which increases the number of double-strand DNA breaks. Bimodal chemo-phototherapeutic liposomes may have a very promising future in oncological therapy, potentially allowing a reduction in the CPT11 concentration required to achieve a therapeutic effect and overcoming resistance to individual cancer treatments.


Asunto(s)
Fotoquimioterapia , Humanos , Células HeLa , Irinotecán , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología
3.
Nanomaterials (Basel) ; 10(12)2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-33321776

RESUMEN

We report the preparation of gold nanoclusters (AuNCs) as a delivery vehicle for the clinically approved photodynamic and chemotherapeutic agents Protoporphyrin IX (PpIX) and doxorubicin (DOX), respectively, and their effect on tumor cells. DOX was attached to the gold nanoclusters through a singlet oxygen-cleavable linker and was therefore released after PpIX irradiation with red light, contributing, synergistically with singlet oxygen, to induce cell death. The doubly functionalized AuNCs proved more effective than a combination of individually functionalized AuNCs. Unlike free DOX, the photoactive nanosystem was non-toxic in the absence of light, which paves the way to introduce a spatiotemporal control of the anticancer therapy and could contribute to reducing the undesirable side effects of DOX.

4.
TH Open ; 4(2): e127-e137, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32607466

RESUMEN

Introduction There is scarce real-world experience regarding direct oral anticoagulants (DOACs) perioperative management. No study before has linked bridging therapy or DOAC-free time (pre-plus postoperative time without DOAC) with outcome. The aim of this study was to investigate real-world management and outcomes. Methods RA-ACOD is a prospective, observational, multicenter registry of adult patients on DOAC treatment requiring surgery. Primary outcomes were thrombotic and hemorrhagic complications. Follow-up was immediate postoperative (24-48 hours) and 30 days. Statistics were performed using a univariate and multivariate analysis. Data are presented as odds ratios (ORs [95% confidence interval]). Results From 26 Spanish hospitals, 901 patients were analyzed (53.5% major surgeries): 322 on apixaban, 304 on rivaroxaban, 267 on dabigatran, 8 on edoxaban. Fourteen (1.6%) patients suffered a thrombotic event, related to preoperative DOAC withdrawal (OR: 1.57 [1.03-2.4]) and DOAC-free time longer than 6 days (OR: 5.42 [1.18-26]). Minor bleeding events were described in 76 (8.4%) patients, with higher incidence for dabigatran (12.7%) versus other DOACs (6.6%). Major bleeding events occurred in 17 (1.9%) patients. Bridging therapy was used in 315 (35%) patients. It was associated with minor (OR: 2.57 [1.3-5.07]) and major (OR: 4.2 [1.4-12.3]) bleeding events, without decreasing thrombotic events. Conclusion This study offers real-world data on perioperative DOAC management and outcomes in a large prospective sample size to date with a high percentage of major surgery. Short-term preprocedural DOAC interruption depending on the drug, hemorrhagic risk, and renal function, without bridging therapy and a reduced DOAC-free time, seems the safest practice.

5.
Cancers (Basel) ; 12(6)2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32485849

RESUMEN

Nanotechnology-based approaches hold substantial potential to avoid chemoresistance and minimize side effects. In this work, we have used biocompatible iron oxide magnetic nanoparticles (MNPs) called MF66 and functionalized with the antineoplastic drug doxorubicin (DOX) against MDA-MB-231 cells. Electrostatically functionalized MNPs showed effective uptake and DOX linked to MNPs was more efficiently retained inside the cells than free DOX, leading to cell inactivation by mitotic catastrophe, senescence and apoptosis. Both effects, uptake and cytotoxicity, were demonstrated by different assays and videomicroscopy techniques. Likewise, covalently functionalized MNPs using three different linkers-disulfide (DOX-S-S-Pyr, called MF66-S-S-DOX), imine (DOX-I-Mal, called MF66-I-DOX) or both (DOX-I-S-S-Pyr, called MF66-S-S-I-DOX)-were also analysed. The highest cell death was detected using a linker sensitive to both pH and reducing environment (DOX-I-S-S-Pyr). The greatest success of this study was to detect also their activity against breast cancer stem-like cells (CSC) from MDA-MB-231 and primary breast cancer cells derived from a patient with a similar genetic profile (triple-negative breast cancer). In summary, these nanoformulations are promising tools as therapeutic agent vehicles, due to their ability to produce efficient internalization, drug delivery, and cancer cell inactivation, even in cancer stem-like cells (CSCs) from patients.

6.
Photochem Photobiol ; 96(3): 458-477, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32077486

RESUMEN

This minireview is devoted to honoring the memory of Dr. Thomas Dougherty, a pioneer of modern photodynamic therapy (PDT). It compiles the most important inputs made by our research group since 2012 in the development of new photosensitizers based on BODIPY chromophore which, thanks to the rich BODIPY chemistry, allows a finely tuned design of the photophysical properties of this family of dyes to serve as efficient photosensitizers for the generation of singlet oxygen. These two factors, photophysical tuning and workable chemistry, have turned BODIPY chromophore as one of the most promising dyes for the development of improved photosensitizers for PDT. In this line, this minireview is mainly related to the establishment of chemical methods and structural designs for enabling efficient singlet oxygen generation in BODIPYs. The approaches include the incorporation of heavy atoms, such as halogens (iodine or bromine) in different number and positions on the BODIPY scaffold, and also transition metal atoms, by their complexation with Ir(III) center, for instance. On the other hand, low-toxicity approaches, without involving heavy metals, have been developed by preparing several orthogonal BODIPY dimers with different substitution patterns. The advantages and drawbacks of all these diverse molecular designs based on BODIPY structural framework are described.


Asunto(s)
Compuestos de Boro/química , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Oxígeno Singlete/química , Humanos , Estructura Molecular , Fármacos Fotosensibilizantes/química
7.
ACS Appl Mater Interfaces ; 12(4): 4295-4307, 2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-31904927

RESUMEN

We have developed a reproducible and facile one step strategy for the synthesis of doxorubicin loaded magnetoliposomes by using a thin-layer evaporation method. Liposomes of around 200 nm were made of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and iron oxide nanoparticles (NPs) with negative, positive, and hydrophobic surfaces that were incorporated outside, inside, or between the lipid bilayers, respectively. To characterize how NPs are incorporated in liposomes, advanced cryoTEM and atomic force microscope (AFM) techniques have been used. It was observed that only when the NPs are attached outside the liposomes, the membrane integrity is preserved (lipid melt transition shifts to 38.7 °C with high enthalpy 34.8 J/g) avoiding the leakage of the encapsulated drug while having good colloidal properties and the best heating efficiency under an alternating magnetic field (AMF). These magnetoliposomes were tested with two cancer cell lines, MDA-MB-231 and HeLa cells. First, 100% of cellular uptake was achieved with a high cell survival (above 80%), which is preserved (83%) for doxorubicin-loaded magnetoliposomes. Then, we demonstrate that doxorubicin release can be triggered by remote control, using a noninvasive external AMF for 1 h, leading to a cell survival reduction of 20%. Magnetic field conditions of 202 kHz and 30 mT seem to be enough to produce an effective heating to avoid drug degradation. In conclusion, these drug-loaded magnetoliposomes prepared in one step could be used for drug release on demand at a specific time and place, efficiently using an external AMF to reduce or even eliminate side effects.


Asunto(s)
Antineoplásicos/química , Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos/métodos , Liposomas/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/farmacología , Doxorrubicina/química , Doxorrubicina/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/instrumentación , Liberación de Fármacos , Humanos , Campos Magnéticos , Nanopartículas/química
8.
Chem Commun (Camb) ; 56(6): 940-943, 2020 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-31850455

RESUMEN

Endowing BODIPY PDT agents with the ability to probe lipid droplets is demonstrated to boost their phototoxicity, allowing the efficient use of highly fluorescent dyes (poor ROS sensitizers) as phototoxic agents. Conversely, this fact opens the way to the development of highly bright ROS photosensitizers for performing photodynamic theragnosis (fluorescence bioimaging and photodynamic therapy) from a single simple agent. On the other hand, the noticeable capability of some of the reported dyes to probe lipid droplets in different cell lines under different conditions reveals their use as privileged probes for advancing the study of interesting lipid droplets by fluorescence microscopy.


Asunto(s)
Compuestos de Boro/química , Colorantes Fluorescentes/química , Gotas Lipídicas/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Células HeLa , Humanos , Microscopía Fluorescente , Estructura Molecular , Imagen Óptica
9.
Mater Sci Eng C Mater Biol Appl ; 107: 110262, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31761230

RESUMEN

Magnetic resonance imaging (MRI) is the most powerful technique for non-invasive diagnosis of human diseases and disorders. Properly designed contrast agents can be accumulated in the damaged zone and be internalized by cells, becoming interesting cellular MRI probes for disease tracking and monitoring. However, this approach is sometimes limited by the relaxation rates of contrast agents currently in clinical use, which show neither optimal pharmacokinetic parameters nor toxicity. In this work, a suitable contrast agent candidate, based on iron oxide nanoparticles (IONPs) coated with polyethyleneglycol, was finely designed, prepared and fully characterized under a physical, chemical and biological point of view. To stand out the real potential of our study, all the experiments were performed in comparison with Ferumoxytol, a FDA approved IONPs. IONPs with a core size of 15 nm and coated with polyethyleneglycol of 5 kDa (OD15-P5) resulted the best ones, being able to be uptaken by both tumoral cells and macrophages and showing no toxicity for in vitro and in vivo experiments. In vitro and in vivo MRI results for OD15-P5 showed r2 relaxivity values higher than Ferumoxitol. Furthermore, the injected OD15-P5 were completely retained at the tumor site for up to 24 h showing high potential as MRI contrast agents for real time long-lasting monitoring of the tumor evolution.


Asunto(s)
Medios de Contraste/química , Compuestos Férricos/química , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/química , Polietilenglicoles/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Nanopartículas de Magnetita/toxicidad , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Neoplasias/diagnóstico por imagen , Tamaño de la Partícula , Siloxanos/química
10.
Cancers (Basel) ; 11(7)2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31295963

RESUMEN

Controlled delivery of multiple chemotherapeutics can improve the effectiveness of treatments and reduce side effects and relapses. Here in, we used albumin-stabilized gold nanoclusters modified with doxorubicin and SN38 (AuNCs-DS) as combined therapy for cancer. The chemotherapeutics are conjugated to the nanostructures using linkers that release them when exposed to different internal stimuli (Glutathione and pH). This system has shown potent antitumor activity against breast and pancreatic cancer cells. Our studies indicate that the antineoplastic activity observed may be related to the reinforced DNA damage generated by the combination of the drugs. Moreover, this system presented antineoplastic activity against mammospheres, a culturing model for cancer stem cells, leading to an efficient reduction of the number of oncospheres and their size. In summary, the nanostructures reported here are promising carriers for combination therapy against cancer and particularly to cancer stem cells.

11.
Eur J Pharm Sci ; 109: 65-77, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28735042

RESUMEN

Irinotecan (CPT-11) is an effective chemotherapeutic agent widely used to treat different cancers. Otherwise, the liposomal delivery of anti-tumor agents has been shown to be a promising strategy. The aim of this study has been to analyze the effect of liposomal CPT-11 (CPT-11lip) on two human cell lines (Hs68 and HeLa) to establish the suitability of this CPT-11 nanocarrier. We have demonstrated the highest uptake of CPT-11lip in comparison with that of CPT-11sol, in lactate buffer, and that CPT-11lip was internalized in the cells through an endocytic process whereas CPT-11sol does so by passive diffusion. CPT-11lip was not cytotoxic to normal fibroblast Hs68 cells, but induced a massive apoptosis accompanied by cell senescence in HeLa cells. CPT-11lip treatment modified the morphology of HeLa cells, induced different cell cycle alterations and accumulated into lysosomes in both cell lines. In particular, CPT-11lip treatment showed that surviving HeLa cells remained in a state of senescence whereas only a temporal growth arrest was induced in Hs68 cells. Results of RT-PCR indicated that the different responses in Hs68 (survival) and HeLa cells (apoptotic death), seemed to be induced by a p53- and p53- independent mechanism, respectively. An analysis of DNA damage also determined that released CPT-11 from liposomes was able to reach the nucleus and exert a genotoxic effect in both cell lines, which was repaired in Hs68 but not in HeLa cells. All results indicate that phospholipid-cholesterol liposomes possess optimum properties for CPT-11 delivery, being biocompatible and selectively cytotoxic against HeLa tumorigenic cells.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Camptotecina/análogos & derivados , Apoptosis/efectos de los fármacos , Camptotecina/administración & dosificación , Línea Celular , Supervivencia Celular/efectos de los fármacos , Daño del ADN , Endocitosis , Células HeLa , Humanos , Irinotecán , Liposomas
12.
Chemistry ; 23(42): 10139-10147, 2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28543812

RESUMEN

Biscyclometalated IrIII complexes involving boron-dipyrromethene (BODIPY)-based ancillary ligands, where the BODIPY unit is grafted to different chelating cores (acetylacetonate for Ir-1 and Ir-2, and bipyridine for Ir-3) by the BODIPY meso position, have been synthesized and characterized. Complexes with the BODIPY moiety directly grafted to acetylacetonate (Ir-1 and Ir-2) exhibit higher absorption coefficients (ϵ≈4.46×104 m-1 cm-1 and 3.38×104 m-1  cm-1 at 517 nm and 594 nm, respectively), higher moderate fluorescence emission (φfl ≈0.08 and 0.22 at 528 nm and 652 nm, respectively) and, in particular, more efficient singlet oxygen generation upon visible-light irradiation (φΔ ≈0.86 and 0.59, respectively) than that exhibited by Ir-3 (φΔ ≈0.51, but only under UV light). Phosphorescence emission, nanosecond time-resolved transient absorption, and DFT calculations suggest that BODIPY-localized long-lived 3 IL states are populated for Ir-1 and Ir-2. In vitro photodynamic therapy (PDT) activity studied for Ir-1 and Ir-2 in HeLa cells shows that such complexes are efficiently internalized into the cells, exhibiting low dark- and high photocytoxicity, even at significantly low complex concentration, making them potentially suitable as theranostic agents.


Asunto(s)
Compuestos de Boro/química , Complejos de Coordinación/química , Iridio/química , Fármacos Fotosensibilizantes/química , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Complejos de Coordinación/síntesis química , Complejos de Coordinación/toxicidad , Colorantes Fluorescentes/química , Células HeLa , Humanos , Microscopía Fluorescente , Fotoquimioterapia , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/toxicidad , Teoría Cuántica , Oxígeno Singlete/química , Oxígeno Singlete/metabolismo , Rayos Ultravioleta
13.
Cancers (Basel) ; 9(2)2017 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-28218672

RESUMEN

A combination of therapies to treat cancer malignancies is at the forefront of research with the aim to reduce drug doses (ultimately side effects) and diminish the possibility of resistance emergence given the multitarget strategy. With this goal in mind, in the present study, we report the combination between the chemotherapeutic drug doxorubicin (DOXO) and the photosensitizing agent pheophorbide a (PhA) to inactivate HeLa cells. Photophysical studies revealed that DOXO can quench the excited states of PhA, detracting from its photosensitizing ability. DOXO can itself photosensitize the production of singlet oxygen; however, this is largely suppressed when bound to DNA. Photodynamic treatments of cells incubated with DOXO and PhA led to different outcomes depending on the concentrations and administration protocols, ranging from antagonistic to synergic for the same concentrations. Taken together, the results indicate that an appropriate combination of DOXO with PhA and red light may produce improved cytotoxicity with a smaller dose of the chemotherapeutic drug, as a result of the different subcellular localization, targets and mode of action of the two agents.

14.
Chemistry ; 23(20): 4837-4848, 2017 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-28165162

RESUMEN

The synthesis, photophysical characterization, and modeling of a new library of halogen-free photosensitizers (PS) based on orthogonal boron dipyrromethene (BODIPY) dimers are reported. Herein we establish key structural factors in order to enhance singlet oxygen generation by judiciously choosing the substitution patterns according to key electronic effects and synthetic accessibility factors. The photosensitization mechanism of orthogonal BODIPY dimers is demonstrated to be strongly related to their intrinsic intramolecular charge transfer (ICT) character through the spin-orbit charge-transfer intersystem crossing (SOCT-ISC) mechanism. Thus, singlet oxygen generation can be effectively modulated through the solvent polarity and the presence of electron-donating or withdrawing groups in one of the BODIPY units. The photodynamic therapy (PDT) activity is demonstrated by in vitro experiments, showing that selected photosensitizers are efficiently internalized into HeLa cells, exhibiting low dark toxicity and high phototoxicity, even at low PS concentration (0.05-5×10-6 m).

15.
Sci Rep ; 6: 38382, 2016 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-27922119

RESUMEN

Promising advances in nanomedicine such as magnetic hyperthermia rely on a precise control of the nanoparticle performance in the cellular environment. This constitutes a huge research challenge due to difficulties for achieving a remote control within the human body. Here we report on the significant double role of the shape of ellipsoidal magnetic nanoparticles (nanorods) subjected to an external AC magnetic field: first, the heat release is increased due to the additional shape anisotropy; second, the rods dynamically reorientate in the orthogonal direction to the AC field direction. Importantly, the heating performance and the directional orientation occur in synergy and can be easily controlled by changing the AC field treatment duration, thus opening the pathway to combined hyperthermic/mechanical nanoactuators for biomedicine. Preliminary studies demonstrate the high accumulation of nanorods into HeLa cells whereas viability analysis supports their low toxicity and the absence of apoptotic or necrotic cell death after 24 or 48 h of incubation.


Asunto(s)
Hipertermia Inducida/métodos , Nanopartículas de Magnetita/química , Nanotubos/química , Anisotropía , Supervivencia Celular , Células HeLa , Humanos , Campos Magnéticos , Nanopartículas de Magnetita/ultraestructura , Nanotubos/ultraestructura , Tamaño de la Partícula
16.
Nanotechnology ; 26(36): 365104, 2015 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-26293792

RESUMEN

Poly(D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) are being considered as nanodelivery systems for photodynamic therapy. The physico-chemical and biological aspects of their use remain largely unknown. Herein we report the results of a study of PLGA NPs for the delivery of the model hydrophobic photosensitizer ZnTPP to HeLa cells. ZnTPP was encapsulated in PLGA with high efficiency and the NPs showed negative zeta potentials and diameters close to 110 nm. Poly(ethylene glycol) (PEG) coating, introduced to prevent opsonization and clearance by macrophages, decreased the size and zeta potential of the NPs by roughly a factor of two and improved their stability in the presence of serum proteins. Photophysical studies revealed two and three populations of ZnTPP and singlet oxygen in uncoated and PEGylated NPs, respectively. Singlet oxygen is confined within the NPs in bare PLGA while it is more easily released into the external medium after PEG coating, which contributes to a higher photocytotoxicity towards HeLa cells in vitro. PLGA NPs are internalized by endocytosis, deliver their cargo to lysosomes and induce cell death by apoptosis upon exposure to light. In conclusion, PLGA NPs coated with PEG show high potential as delivery systems for photodynamic applications.


Asunto(s)
Ácido Láctico/química , Nanopartículas/química , Fármacos Fotosensibilizantes/farmacología , Polietilenglicoles/química , Ácido Poliglicólico/química , Oxígeno Singlete/metabolismo , Apoptosis , Sistemas de Liberación de Medicamentos , Células HeLa , Humanos , Tamaño de la Partícula , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Propiedades de Superficie
17.
Breast Cancer Res ; 17: 66, 2015 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-25968050

RESUMEN

INTRODUCTION: Tumor cells can effectively be killed by heat, e.g. by using magnetic hyperthermia. The main challenge in the field, however, is the generation of therapeutic temperatures selectively in the whole tumor region. We aimed to improve magnetic hyperthermia of breast cancer by using innovative nanoparticles which display a high heating potential and are functionalized with a cell internalization and a chemotherapeutic agent to increase cell death. METHODS: The superparamagnetic iron oxide nanoparticles (MF66) were electrostatically functionalized with either Nucant multivalent pseudopeptide (N6L; MF66-N6L), doxorubicin (DOX; MF66-DOX) or both (MF66-N6LDOX). Their cytotoxic potential was assessed in a breast adenocarcinoma cell line MDA-MB-231. Therapeutic efficacy was analyzed on subcutaneous MDA-MB-231 tumor bearing female athymic nude mice. RESULTS: All nanoparticle variants showed an excellent heating potential around 500 W/g Fe in the alternating magnetic field (AMF, conditions: H=15.4 kA/m, f=435 kHz). We could show a gradual inter- and intracellular release of the ligands, and nanoparticle uptake in cells was increased by the N6L functionalization. MF66-DOX and MF66-N6LDOX in combination with hyperthermia were more cytotoxic to breast cancer cells than the respective free ligands. We observed a substantial tumor growth inhibition (to 40% of the initial tumor volume, complete tumor regression in many cases) after intratumoral injection of the nanoparticles in vivo. The proliferative activity of the remaining tumor tissue was distinctly reduced. CONCLUSION: The therapeutic effects of breast cancer magnetic hyperthermia could be strongly enhanced by the combination of MF66 functionalized with N6L and DOX and magnetic hyperthermia. Our approach combines two ways of tumor cell killing (magnetic hyperthermia and chemotherapy) and represents a straightforward strategy for translation into the clinical practice when injecting nanoparticles intratumorally.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Compuestos Férricos/química , Hipertermia Inducida/métodos , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Animales , Apoptosis , Neoplasias de la Mama/diagnóstico , Línea Celular Tumoral , Modelos Animales de Enfermedad , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Humanos , Hipertermia Inducida/efectos adversos , Nanopartículas del Metal/efectos adversos , Ratones , Ratones Desnudos , Microtomografía por Rayos X , Ensayos Antitumor por Modelo de Xenoinjerto
18.
J Nanobiotechnology ; 13: 16, 2015 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-25880445

RESUMEN

BACKGROUND: Different superparamagnetic iron oxide nanoparticles have been tested for their potential use in cancer treatment, as they enter into cells with high effectiveness, do not induce cytotoxicity, and are retained for relatively long periods of time inside the cells. We have analyzed the interaction, internalization and biocompatibility of dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles with an average diameter of 15 nm and negative surface charge in MCF-7 breast cancer cells. RESULTS: Cells were incubated with dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles for different time intervals, ranging from 0.5 to 72 h. These nanoparticles showed efficient internalization and relatively slow clearance. Time-dependent uptake studies demonstrated the maximum accumulation of dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles after 24 h of incubation, and afterwards they were slowly removed from cells. Superparamagnetic iron oxide nanoparticles were internalized by energy dependent endocytosis and localized in endosomes. Transmission electron microscopy studies showed macropinocytosis uptake and clathrin-mediated internalization depending on the nanoparticles aggregate size. MCF-7 cells accumulated these nanoparticles without any significant effect on cell morphology, cytoskeleton organization, cell cycle distribution, reactive oxygen species generation and cell viability, showing a similar behavior to untreated control cells. CONCLUSIONS: All these findings indicate that dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles have excellent properties in terms of efficiency and biocompatibility for application to target breast cancer cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Materiales Biocompatibles Revestidos/metabolismo , Compuestos Férricos/metabolismo , Nanopartículas de Magnetita/química , Succímero/metabolismo , Mama/citología , Mama/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Citoesqueleto/efectos de los fármacos , Endocitosis , Endosomas/metabolismo , Femenino , Compuestos Férricos/química , Humanos , Pinocitosis , Succímero/química
19.
Nanotechnology ; 26(13): 135101, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25760138

RESUMEN

Many therapeutic applications of magnetic nanoparticles involve the local administration of nanometric iron oxide based materials as seeds for magnetothermia or drug carriers. A simple and widespread way of controlling the process using x-ray computed tomography (CT) scanners is desirable. The combination of iron and bismuth in one entity will increase the atenuation of x-rays, offering such a possibility. In order to check this possibility core-shell nanocrystals of iron oxide@bismuth oxide have been synthesized by an aqueous route and stabilized in water by polyethylene glycol (PEG), and we have evaluated their ability to generate contrast by CT and magnetic resonance imaging (MRI) to measure the radiopacity and proton relaxivities using phantoms. High-resolution scanning transmission electron microscopy (STEM) revealed that the material consists of a highly crystalline 8 nm core of maghemite and a 1 nm shell of bismuth atoms either isolated or clustered on the nanocrystal's surface. The comparison of µCT and MRI images of mice acquired in the presence of the contrast shows that when local accumulations of the magnetic nanoparticles take place, CT images are more superior in the localization of the magnetic nanoparticles than MRI images, which results in magnetic field inhomogeneity artifacts.

20.
Int J Mol Sci ; 15(12): 22772-85, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25501332

RESUMEN

Photodynamic therapy (PDT) is a cancer treatment modality based on the administration of a photosensitizer (PS), which accumulates preferentially in tumor cells. Subsequent irradiation of the neoplastic area triggers a cascade of photochemical reactions that leads to the formation of highly reactive oxygen species responsible for cell inactivation. Photodynamic treatments in vitro are performed with the PS, zinc-phthalocyanine (ZnPc). The PS is near the plasma membrane during uptake and internalization. Inactivation clearly occurs by a necrotic process, manifested by nuclear pyknosis, negative TUNEL and Annexin V assays and non-relocation of cytochrome c. In contrast, by increasing the incubation time, ZnPc is accumulated in the Golgi apparatus and produces cell inactivation with characteristics of apoptosis and necrosis: TUNEL positive, relocated cytochrome c and negative Annexin V assay. This type of death produces a still undescribed granulated nuclear morphology, which is different from that of necrosis or apoptosis. This morphology is inhibited by necrostatin-1, a specific inhibitor of regulated necrosis.


Asunto(s)
Indoles/farmacología , Necrosis/etiología , Necrosis/patología , Compuestos Organometálicos/farmacología , Fármacos Fotosensibilizantes/farmacología , Transporte Biológico , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Núcleo Celular/efectos de los fármacos , Núcleo Celular/patología , Núcleo Celular/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Relación Dosis-Respuesta a Droga , Células HeLa , Humanos , Imidazoles/farmacología , Indoles/metabolismo , Isoindoles , Compuestos Organometálicos/metabolismo , Fotoquimioterapia , Fármacos Fotosensibilizantes/metabolismo , Compuestos de Zinc
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