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1.
J Am Chem Soc ; 146(2): 1644-1656, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38174960

RESUMO

Photodynamic therapy (PDT), an emergent noninvasive cancer treatment, is largely dependent on the presence of efficient photosensitizers (PSs) and a sufficient oxygen supply. However, the therapeutic efficacy of PSs is greatly compromised by poor solubility, aggregation tendency, and oxygen depletion within solid tumors during PDT in hypoxic microenvironments. Despite the potential of PS-based metal-organic frameworks (MOFs), addressing hypoxia remains challenging. Boron dipyrromethene (BODIPY) chromophores, with excellent photostability, have exhibited great potential in PDT and bioimaging. However, their practical application suffers from limited chemical stability under harsh MOF synthesis conditions. Herein, we report the synthesis of the first example of a Zr-based MOF, namely, 69-L2, exclusively constructed from the BODIPY-derived ligands via a single-crystal to single-crystal post-synthetic exchange, where a direct solvothermal method is not applicable. To increase the PDT performance in hypoxia, we modify 69-L2 with fluorinated phosphate-functionalized methoxy poly(ethylene glycol). The resulting 69-L2@F is an oxygen carrier, enabling tumor oxygenation and simultaneously acting as a PS for reactive oxygen species (ROS) generation under LED irradiation. We demonstrate that 69-L2@F has an enhanced PDT effect in triple-negative breast cancer MDA-MB-231 cells under both normoxia and hypoxia. Following positive results, we evaluated the in vivo activity of 69-L2@F with a hydrogel, enabling local therapy in a triple-negative breast cancer mice model and achieving exceptional antitumor efficacy in only 2 days. We envision BODIPY-based Zr-MOFs to provide a solution for hypoxia relief and maximize efficacy during in vivo PDT, offering new insights into the design of promising MOF-based PSs for hypoxic tumors.


Assuntos
Compostos de Boro , Estruturas Metalorgânicas , Neoplasias , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Estruturas Metalorgânicas/química , Fotoquimioterapia/métodos , Zircônio/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Oxigênio , Neoplasias/terapia , Hipóxia , Linhagem Celular Tumoral , Microambiente Tumoral
2.
Curr Opin Biotechnol ; 81: 102947, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37163824

RESUMO

Regeneration of damaged cornea can save vision for millions of patients. Most of these patients are waiting for transplantation of a donor cornea or suitable substitute to restore vision. Although donor cornea transplantation is the most clinically accepted treatment, shortage of donor cornea results in almost 69 out of every 70 patients untreated with the waiting list for transplantation drastically increasing every year according to a prepandemic estimation. Therefore, corneal replacements are coming up as a cutting-edge alternative strategy. In view of the peptides, especially collagen-like peptides and peptide amphiphiles with bioactive functional motifs demonstrate promising avenue for the corneal tissue engineering and promoting regeneration, by their hierarchical self-assembling propensity to acquire desired nano- to macroscale 3D architecture. Here, we analyze rational peptide designing, self-assembly, and strategies of peptide/peptide-based nanoscale building blocks to create the extracellular matrix mimetic implants for functional regeneration of the cornea.


Assuntos
Córnea , Regeneração , Humanos , Córnea/cirurgia , Engenharia Biomédica , Engenharia Tecidual/métodos , Peptídeos
3.
ACS Appl Mater Interfaces ; 15(14): 17485-17494, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36976817

RESUMO

Despite the enormous advancements in nanomedicine research, a limited number of nanoformulations are available on the market, and few have been translated to clinics. An easily scalable, sustainable, and cost-effective manufacturing strategy and long-term stability for storage are crucial for successful translation. Here, we report a system and method to instantly formulate NF achieved with a nanoscale polyelectrolyte coacervate-like system, consisting of anionic pseudopeptide poly(l-lysine isophthalamide) derivatives, polyethylenimine, and doxorubicin (Dox) via simple "mix-and-go" addition of precursor solutions in seconds. The coacervate-like nanosystem shows enhanced intracellular delivery of Dox to patient-derived multidrug-resistant (MDR) cells in 3D tumor spheroids. The results demonstrate the feasibility of an instant drug formulation using a coacervate-like nanosystem. We envisage that this technique can be widely utilized in the nanomedicine field to bypass the special requirement of large-scale production and elongated shelf life of nanomaterials.


Assuntos
Nanopartículas , Nanoestruturas , Neoplasias , Humanos , Estudos de Viabilidade , Doxorrubicina/farmacologia , Doxorrubicina/química , Neoplasias/patologia , Portadores de Fármacos/química , Nanopartículas/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos
4.
Sci Rep ; 12(1): 9108, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35650270

RESUMO

Development of an artificial cornea can potentially fulfil the demand of donor corneas for transplantation as the number of donors is far less than needed to treat corneal blindness. Collagen-based artificial corneas stand out as a regenerative option, having promising clinical outcomes. Collagen crosslinked with chemical crosslinkers which modify the parent functional groups of collagen. However, crosslinkers are usually cytotoxic, so crosslinkers need to be removed from implants completely before application in humans. In addition, crosslinked products are mechanically weak and susceptible to enzymatic degradation. We developed a crosslinker free supramolecular gelation strategy using pyrene conjugated dipeptide amphiphile (PyKC) consisting of lysine and cysteine; in which collagen molecules are intertwined inside the PyKC network without any functional group modification of the collagen. The newly developed collagen implants (Coll-PyKC) are optically transparent and can effectively block UV light, are mechanically and enzymatically stable, and can be sutured. The Coll-PyKC implants support the growth and function of all corneal cells, trigger anti-inflammatory differentiation while suppressing the pro-inflammatory differentiation of human monocytes. Coll-PyKC implants can restrict human adenovirus propagation. Therefore, this crosslinker-free strategy can be used for the repair, healing, and regeneration of the cornea, and potentially other damaged organs of the body.


Assuntos
Colágeno , Córnea , Colágeno/metabolismo , Córnea/metabolismo , Humanos , Próteses e Implantes , Regeneração , Raios Ultravioleta
5.
ACS Appl Mater Interfaces ; 13(20): 23410-23422, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33978409

RESUMO

Nanomedicine is seen as a potential central player in the delivery of personalized medicine. Biocompatibility issues of nanoparticles have largely been resolved over the past decade. Despite their tremendous progress, less than 1% of applied nanosystems can hit their intended target location, such as a solid tumor, and this remains an obstacle to their full ability and potential with a high translational value. Therefore, achieving immune-tolerable, blood-compatible, and biofriendly nanoparticles remains an unmet need. The translational success of nanoformulations from bench to bedside involves a thorough assessment of their design, compatibility beyond cytotoxicity such as immune toxicity, blood compatibility, and immune-mediated destruction/rejection/clearance profile. Here, we report a one-pot process-engineered synthesis of ultrasmall gold nanoparticles (uGNPs) suitable for better body and renal clearance delivery of their payloads. We have obtained uGNP sizes of as low as 3 nm and have engineered the synthesis to allow them to be accurately sized (almost nanometer by nanometer). The synthesized uGNPs are biocompatible and can easily be functionalized to carry drugs, peptides, antibodies, and other therapeutic molecules. We have performed in vitro cell viability assays, immunotoxicity assays, inflammatory cytokine analysis, a complement activation study, and blood coagulation studies with the uGNPs to confirm their safety. These can help to set up a long-term safety-benefit framework of experimentation to reveal whether any designed nanoparticles are immune-tolerable and can be used as payload carriers for next-generation vaccines, chemotherapeutic drugs, and theranostic agents with better body clearance ability and deep tissue penetration.


Assuntos
Materiais Biocompatíveis , Ouro , Imunidade Inata , Nanopartículas Metálicas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Coagulação Sanguínea/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ouro/química , Ouro/toxicidade , Humanos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/fisiologia , Teste de Materiais , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Modelos Imunológicos , Citrato de Sódio , Células THP-1 , Taninos
6.
Biomaterials ; 264: 120410, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979655

RESUMO

Transdermal drug delivery exhibited encouraging prospects, especially through superficial drug administration routes. However, only a few limited lipophilic drug molecules could cross the skin barrier, those are with low molecular weight and rational Log P value. Microneedles (MNs) can overcome these limitations to deliver numerous drugs into the dermal layer by piercing the outermost skin layer of the body. In the case of superficial cancer treatments, topical drug administration faces severely low transfer efficiency, and systemic treatments are always associated with side effects and premature drug degradation. MN-based systems have achieved excellent technical capabilities and been tested for pre-clinical chemotherapy, photothermal therapy, photodynamic therapy, and immunotherapy. In this review, we will focus on the features, progress, and opportunities of MNs in the anticancer drug delivery system. Then, we will discuss the strategies and advantages in these works and summarize challenges, perspectives, and translational potential for future applications.


Assuntos
Antineoplásicos , Preparações Farmacêuticas , Administração Cutânea , Sistemas de Liberação de Medicamentos , Microinjeções , Agulhas
7.
Biomater Sci ; 8(18): 5210-5218, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32844846

RESUMO

Nanotechnology has a remarkable impact on the preclinical development of future medicines. However, the complicated preparation and systemic toxicity to living systems prevent them from translation to clinical applications. In the present report, we developed a polyepicatechin-based on/off switchable ultra-sensitive magnetic resonance imaging (MRI) visible theranostic nanoparticle (PEMN) for image-guided photothermal therapy (PTT) using our strategy of integrating polymerization and biomineralization into the protein template. We have exploited natural polyphenols as the near infra-red (NIR) switchable photothermal source and MnO2 for the MRI-guided theranostics. PEMN demonstrates excellent MRI contrast ability with a longitudinal relaxivity value up to 30.01 mM-1 s-1. PEMN has shown great tumor inhibition on orthotopic breast tumors and the treatment could be made switchable with an on/off interchangeable mode as needed. PEMN was found to be excretable mainly through the kidneys, avoiding potential systemic toxicity. Thus, PEMN could be extremely useful for developing on-demand therapeutics via'see it and treat it' means with distinguished MRI capability and on/off switchable photothermal properties.


Assuntos
Catequina , Nanomedicina Teranóstica , Linhagem Celular Tumoral , Humanos , Imageamento por Ressonância Magnética , Compostos de Manganês , Óxidos
8.
Biomater Sci ; 8(6): 1615-1621, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-31967620

RESUMO

Nanotheranostics (combined diagnosis and therapy) is emerging as an integral part of future therapeutic strategies. However, the development and fabrication of a nanotheranostic module involves multistep processes and always faces formulation challenges. The complexity involved in its multi-step formulations hinders its reproducible industrial production and clinical translation. Therefore, a facile synthesis of multifunctional nanotheranostics is critical to its translational success. In this report, we have developed a one-pot facile strategy to prepare a MRI-visible photothermal theranostic switchable module (T-SWITCH). These nanoparticles are synthesized through polymerization of levodopa together with the reduction of KMnO4 in the presence of silk sericin for the formation of manganese dioxide particles within the T-SWITCH. The synthesized T-SWITCH showed a uniform size distribution of around 95.77 nm and high longitudinal relaxivity coefficient (r1) of up to 61.94 mM-1 s-1. The reported r1 of the T-SWITCH is exceedingly higher than that of any other previously reported manganese-based contrast agents with first-rate in vitro and in vivo contrast enhancement capability. The T-SWITCH can be activated to switch its therapeutic mode using near-infrared (NIR) light. It exhibited strong excitable absorption in the safer and biological NIR window between 650 and 900 nm. We have validated the significant anti-cancer therapeutic efficacy of T-SWITCH both in vitro and in vivo through switchable photothermal therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Levodopa/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Permanganato de Potássio/química , Sericinas/química , Animais , Linhagem Celular Tumoral , Feminino , Células HeLa , Humanos , Levodopa/química , Levodopa/farmacologia , Camundongos , Células NIH 3T3 , Nanopartículas , Fotoquimioterapia , Nanomedicina Teranóstica , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Ethnopharmacol ; 247: 112283, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31605736

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bulbus Fritillaria cirrhosa D. Don (BFC) is a Chinese traditional herbal medicine that has long been used as an indispensable component in herbal prescriptions for bronchopulmonary diseases due to its well-established strong anti-inflammation and pulmonary harmonizing effects. Interestingly, there are few case reports in traditional Chinese medicine available where they found it to contribute in anti-tumor therapies. Imperialine is one of the most favored active substances extracted from BFC and has been widely recognized as an anti-inflammatory agent. AIM OF THE STUDY: The aim of the current work is to provide first-hand evidences both in vitro and in vivo showing that imperialine exerts anti-cancer effects against non-small cell lung cancer (NSCLC), and to explore the molecular mechanism of this anti-tumor activity. It is also necessary to examine its systemic toxicity, and to investigate how to develop strategies for feasible clinical translation of imperialine. MATERIALS AND METHODS: To investigate anti-NSCLC efficacy of imperialine using both in vitro and in vivo methods where A549 cell line were chosen as in vitro model NSCLC cells and A549 tumor-bearing mouse model was constructed for in vivo study. The detailed underlying anti-cancer mechanism has been systematically explored for the first time through a comprehensive set of molecular biology methods mainly including immunohistochemistry, western blot and enzyme-linked immunosorbent assays. The toxicity profile of imperialine treatments were evaluated using healthy nude mice by examining hemogram and histopathology. An imperialine-loaded liposomal drug delivery system was developed using thin film hydration method to evaluate target specific delivery. RESULTS: The results showed that imperialine could suppress both NSCLC tumor and associated inflammation through an inflammation-cancer feedback loop in which NF-κB activity was dramatically inhibited by imperialine. The NSCLC-targeting liposomal system was successfully developed for targeted drug delivery. The developed platform could favorably enhance imperialine cellular uptake and in vivo accumulation at tumor sites, thus improving overall anti-tumor effect. The toxicity assays revealed imperialine treatments did not significantly disturb blood cell counts in mice or exert any significant damage to the main organs. CONCLUSIONS: Imperialine exerts anti-cancer effects against NSCLC both in vitro and in vivo, and this previously unknown function is related to NF-κB centered inflammation-cancer feedback loop. Imperialine mediated anti-cancer activity is not through cytotoxicity and exhibit robust systemic safety. Furthermore, the liposome-based system we commenced would dramatically enhance therapeutic effects of imperialine while exhibiting extremely low side effects both on cellular and in NSCLC model. This work has identified imperialine as a promising novel anti-cancer compound and offered an efficient target-delivery solution that greatly facilitate practical use of imperialine.


Assuntos
Alcaloides/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cevanas/administração & dosagem , Medicamentos de Ervas Chinesas/administração & dosagem , Fritillaria/química , Neoplasias Pulmonares/tratamento farmacológico , Células A549 , Alcaloides/efeitos adversos , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Contagem de Células Sanguíneas , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Cevanas/efeitos adversos , Cevanas/química , Cevanas/isolamento & purificação , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Retroalimentação Fisiológica/efeitos dos fármacos , Humanos , Lipossomos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/imunologia , Testes de Toxicidade , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Sci Rep ; 9(1): 20066, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882620

RESUMO

One of the hallmarks of cancers is their ability to develop resistance against therapeutic agents. Therefore, developing effective in vitro strategies to identify drug resistance remains of paramount importance for successful treatment. One of the ways cancer cells achieve drug resistance is through the expression of efflux pumps that actively pump drugs out of the cells. To date, several studies have investigated the potential of using 3-dimensional (3D) multicellular tumor spheroids (MCSs) to assess drug resistance; however, a unified system that uses MCSs to differentiate between multi drug resistance (MDR) and non-MDR cells does not yet exist. In the present report we describe MCSs obtained from post-diagnosed, pre-treated patient-derived (PTPD) cell lines from head and neck squamous cancer cells (HNSCC) that often develop resistance to therapy. We employed an integrated approach combining response to clinical drugs and screening cytotoxicity, monitoring real-time drug uptake, and assessing transporter activity using flow cytometry in the presence and absence of their respective specific inhibitors. The report shows a comparative response to MDR, drug efflux capability and reactive oxygen species (ROS) activity to assess the resistance profile of PTPD MCSs and two-dimensional (2D) monolayer cultures of the same set of cell lines. We show that MCSs provide a robust and reliable in vitro model to evaluate clinical relevance. Our proposed strategy can also be clinically applicable for profiling drug resistance in cancers with unknown resistance profiles, which consequently can indicate benefit from downstream therapy.


Assuntos
Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Esferoides Celulares , Células Tumorais Cultivadas
11.
J Control Release ; 311-312: 104-116, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31484040

RESUMO

Currently, most anti-cancer therapies are still haunted by serious and deleterious adverse effects. Here, we report a highly biocompatible tumor cell-targeting delivery systems utilizing exosome-like vesicles (ELVs) that delivers a low-toxicity anti-cancer agent imperialine against non-small cell lung cancer (NSCLC). First, we introduced a novel micelle-aided method to efficiently load imperialine into intact ELVs. Then, integrin α3ß1-binding octapeptide cNGQGEQc was modified onto ELV platform for tumor targeting as integrin α3ß1 is overexpressed on NSCLC cells. This system not only significantly improved imperialine tumor accumulation and retention, but also had extremely low systemic toxicity both in vitro and in vivo. Our discoveries offer new ways to utilize ELV more efficiently for both drug loading and targeting. The solid pharmacokinetics improvement and extraordinary safety of this system also highlight possibilities of alternative long course cancer therapies using similar strategies.


Assuntos
Anti-Inflamatórios/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cevanas/administração & dosagem , Exossomos , Neoplasias Pulmonares/tratamento farmacológico , Nanoestruturas/administração & dosagem , Oligopeptídeos/administração & dosagem , Animais , Anti-Inflamatórios/farmacocinética , Antineoplásicos/farmacocinética , Linhagem Celular , Cevanas/farmacocinética , Humanos , Integrina alfa3 , Ligantes , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Oligopeptídeos/farmacocinética
12.
Artigo em Inglês | MEDLINE | ID: mdl-31380358

RESUMO

Platelets, one of the most sensitive blood cells, can be activated by a range of external and internal stimuli including physical, chemical, physiological, and/or non-physiological agents. Platelets need to respond promptly during injury to maintain blood hemostasis. The time profile of platelet aggregation is very complex, especially in the presence of the agonist adenosine 5'-diphosphate (ADP), and it is difficult to probe such complexity using traditional linear dose response models. In the present study, we explored functional analysis techniques to characterize the pattern of platelet aggregation over time in response to nanoparticle induced perturbations. This has obviated the need to represent the pattern of aggregation by a single summary measure and allowed us to treat the entire aggregation profile over time, as the response. The modeling was performed in a flexible manner, without any imposition of shape restrictions on the curve, allowing smooth platelet aggregation over time. The use of a probabilistic framework not only allowed statistical prediction and inference of the aggregation signatures, but also provided a novel method for the estimation of higher order derivatives of the curve, thereby allowing plausible estimation of the extent and rate of platelet aggregation kinetics over time. In the present study, we focused on the estimated first derivative of the curve, obtained from the platelet optical aggregometric profile over time and used it to discern the underlying kinetics as well as to study the effects of ADP dosage and perturbation with gold nanoparticles. In addition, our method allowed the quantification of the extent of inter-individual signature variations. Our findings indicated several hidden features and showed a mixture of zero and first order kinetics interrupted by a metastable zero order ADP dose dependent process. In addition, we showed that the two first order kinetic constants were ADP dependent. However, we were able to perturb the overall kinetic pattern using gold nanoparticles, which resulted in autocatalytic aggregation with a higher aggregate mass and which facilitated the aggregation rate.

13.
Trends Pharmacol Sci ; 40(6): 403-418, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31076247

RESUMO

Metastasis is a major cause of cancer-related mortality, accounting for 90% of cancer deaths. The explosive growth of cancer biology research has revealed new mechanistic network information and pathways that promote metastasis. Consequently, a large number of antitumor agents have been developed and tested for their antimetastatic efficacy. Despite their exciting cytotoxic effects on tumor cells in vitro and antitumor activities in preclinical studies in vivo, only a few have shown potent antimetastatic activities in clinical trials. In this review, we provide a brief overview of current antimetastatic strategies that show clinical efficacy and review nanotechnology-based approaches that are currently being incorporated into these therapies to mitigate challenges associated with treating cancer metastasis.


Assuntos
Antineoplásicos/administração & dosagem , Nanomedicina/métodos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Antineoplásicos/química , Ensaios Clínicos como Assunto , Humanos , Micelas , Nanopartículas/química , Metástase Neoplásica , Neoplasias/irrigação sanguínea , Células Neoplásicas Circulantes/efeitos dos fármacos , Células Neoplásicas Circulantes/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia
14.
Sci Rep ; 5: 14571, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26415561

RESUMO

Throughout the world, there are increasing demands for alternate approaches to advanced cancer therapeutics. Numerous potentially chemotherapeutic compounds are developed every year for clinical trial and some of them are considered as potential drug candidates. Nanotechnology-based approaches have accelerated the discovery process, but the key challenge still remains to develop therapeutically viable and physiologically safe materials suitable for cancer therapy. Here, we report a high turnover, on/off-switchable functionally popping reactive oxygen species (ROS) generator using a smart mesoporous titanium dioxide popcorn (TiO2 Pops) nanoarchitecture. The resulting TiO2 Pops, unlike TiO2 nanoparticles (TiO2 NPs), are exceptionally biocompatible with normal cells. Under identical conditions, TiO2 Pops show very high photocatalytic activity compared to TiO2 NPs. Upon on/off-switchable photo activation, the TiO2 Pops can trigger the generation of high-turnover flash ROS and can deliver their potential anticancer effect by enhancing the intracellular ROS level until it crosses the threshold to open the 'death gate', thus reducing the survival of cancer cells by at least six times in comparison with TiO2 NPs without affecting the normal cells.


Assuntos
Antineoplásicos/toxicidade , Nanopartículas Metálicas/toxicidade , Espécies Reativas de Oxigênio/agonistas , Titânio/farmacologia , Antineoplásicos/síntese química , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Células HEK293 , Humanos , Luz , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Especificidade de Órgãos , Estresse Oxidativo , Processos Fotoquímicos , Espécies Reativas de Oxigênio/metabolismo , Titânio/química
15.
Carcinogenesis ; 35(4): 747-59, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24531939

RESUMO

Despite decades of search for anticancer drugs targeting solid tumors, this group of diseases remains largely incurable, especially if in advanced, metastatic stage. In this review, we draw comparison between reprogramming and carcinogenesis, as well as between stem cells (SCs) and cancer stem cells (CSCs), focusing on changing garniture of adhesion molecules. Furthermore, we elaborate on the role of adhesion molecules in the regulation of (cancer) SCs division (symmetric or asymmetric), and in evolving interactions between CSCs and extracellular matrix. Among other aspects, we analyze the role and changes of expression of key adhesion molecules as cancer progresses and metastases develop. Here, the role of cadherins, integrins, as well as selected transcription factors like Twist and Snail is highlighted, not only in the regulation of epithelial-to-mesenchymal transition but also in the avoidance of anoikis. Finally, we briefly discuss recent developments and new strategies targeting CSCs, which focus on adhesion molecules or targeting tumor vasculature.


Assuntos
Moléculas de Adesão Celular/fisiologia , Células-Tronco Neoplásicas/citologia , Células-Tronco/citologia , Transição Epitelial-Mesenquimal , Humanos
16.
Adv Healthc Mater ; 3(4): 526-35, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23983185

RESUMO

The development of MRI-visual order-disorder structures for cancer nanomedicine explores a pH-triggered mechanism for theragnosis of tumor hallmark functions. Superparamagnetic iron oxide nanoparticles (SPIONs) stabilized with amphiphilic poly(styrene)-b-poly(acrylic acid)-doxorubicin with folic acid (FA) surfacing are employed as a multi-functional approach to specifically target, diagnose, and deliver drugs via a single nanoscopic platform for cancer therapy. The functional aspects of the micellar nanocomposite is investigated in vitro using human breast SkBr3 and colon cancer HCT116 cell lines for the delivery, release, localization, and anticancer activity of the drug. For the first time, concentration-dependent T2 -weighted MRI contrast for a monolayer of clustered cancer cells is shown. The pH tunable order-disorder transition of the core-shell structure induces the relative changes in MRI contrast. The outcomes elucidate the potential of this material for smart cancer theranostics by delivering non-invasive real-time diagnosis, targeted therapy, and monitoring the course and response of the action before, during, and after the treatment regimen.


Assuntos
Antineoplásicos/química , Meios de Contraste/química , Portadores de Fármacos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/química , Micelas , Nanocompostos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Doxorrubicina/farmacocinética , Ácido Fólico/química , Ácido Fólico/farmacocinética , Humanos , Nanopartículas de Magnetita/administração & dosagem , Nanomedicina , Polímeros/química
17.
Trends Biotechnol ; 32(1): 21-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24246361

RESUMO

Overexpression of oncogenes or loss of tumour suppressors can transform a normal cell to a cancerous one, resulting in uncontrolled regulation of intracellular signalling pathways and immunity to stresses, which both pose therapeutic challenges. Conventional approaches to cancer therapy, although they are effective at killing cancer cells, may still fail due to inadequate biodistribution and unwanted side effects. Nanotechnology-based approaches provide a promising alternative, with the possibility of targeting cells at an early stage, during their transformation into cancer cells. This review considers techniques that specifically target those molecular changes, which begin in only a very small percentage of normal cells as they undergo transformation. These techniques are crucial for early-stage diagnosis and therapy.


Assuntos
Antineoplásicos , Sistemas de Liberação de Medicamentos , Nanomedicina , Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Humanos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico
18.
Nanomedicine ; 7(4): 376-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21310267

RESUMO

The nanoparticle (NP) response of platelets is shown to be critically dependent on extent of preactivation of platelets by an agonist like ADP. A transition from de-aggregatory to aggregatory state is triggered in the presence of gold NPs (AuNP) only in such critical conditions. Adhered and suspended platelets respond differentially to NPs. Preactivation in the adhered state induced by shear force explains such observation. The NP effect is associated with enhanced release reaction, tyrosine phosphorylation and CD62P expression level. Unlike cancer cells, whose response is maximal when NP size is optimal (within the range 50 - 70 nm), the platelet response monotonically increases with reduction of the AuNP size. The uptake study, using quenching of quinacrine hydrochloride fluorescence by AuNP, indicates that accumulation 18 nm AuNP is several-fold higher than the 68 nm AuNP. It is further shown that AuNP response can provide a simple measure for thrombotic risk associated with nano-drugs. FROM THE CLINICAL EDITOR: Platelet aggregation can be triggered in the presence of gold nanoparticles (AuNP). Platelet response monotonically increases with reduction of the AuNP size. AuNP response can provide a simple measure for thrombotic risk associated with nano-drugs.


Assuntos
Plaquetas/efeitos dos fármacos , Ouro/química , Nanopartículas Metálicas/química , Trifosfato de Adenosina/metabolismo , Plaquetas/metabolismo , Plaquetas/ultraestrutura , Humanos , Nanopartículas Metálicas/administração & dosagem , Microscopia Eletrônica de Varredura , Fosforilação/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Tirosina/metabolismo
19.
Nanomedicine ; 3(2): 111-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17572353

RESUMO

Gold nanoparticles (GNPs) are considered a potential probe to detect cancer. The present article investigates whether GNPs, even in the absence of any specific functionalization, induce any cell-specific response. We report GNP-induced death response in human carcinoma lung cell line A549. In contrast, the two other cell lines tested, BHK21 (baby hamster kidney) and HepG2 (human hepatocellular liver carcinoma), remained unaffected by GNP treatment. The specificity of the induction of the death response in A549 cells implies that GNPs do not universally target all cell types. Flow-cytometric studies indicated that the response was dose dependent and had a threshold effect (in A549). Gradual increase in GNP concentration induces a proportional cleavage of poly(ADP-ribose) polymerase. The programmed nature of the death response is implied, because such cleavage follows activation of caspases. Notably, at higher GNP concentration there was an asymmetric accumulation of GNPs in the periphery outside the cell nucleus of the A549 cells. This was confirmed by confocal microscopy, a green scattering (possibly, surface-enhanced Raman effect) appearing on selective z-slices of the image.


Assuntos
Apoptose/efeitos dos fármacos , Ouro/administração & dosagem , Rim/citologia , Rim/efeitos dos fármacos , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/patologia , Nanopartículas/administração & dosagem , Animais , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Cricetinae , Humanos , Teste de Materiais
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