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1.
J Drug Target ; 25(6): 523-531, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28140690

ABSTRACT

Notch pathway was found to be activated in most glioblastomas (GBMs), underlining the importance of Notch in formation and recurrence of GBM. In this study, a Notch inhibitory peptide, dominant negative MAML (dnMAML), was conjugated to elastin-like polypeptide (ELP) for tumor targeted delivery. ELP is a thermally responsive polypeptide that can be actively and passively targeted to the tumor site by localized application of hyperthermia. This complex was further modified with the addition of a cell penetrating peptide, SynB1, for improved cellular uptake and blood-brain barrier penetration. The SynB1-ELP1-dnMAML was examined for its cellular uptake, cytotoxicity, apoptosis, cell cycle inhibition and the inhibition of target genes' expression. SynB1-ELP1-dnMAML inhibited the growth of D54 and U251 cells by inducing apoptosis and cell cycle arrest, especially in the presence of hyperthermia. Hyperthermia increased overall uptake of the polypeptide by the cells and enhanced the resulting pharmacological effects of dnMAML, showing the inhibition of targets of Notch pathway such as Hes-1 and Hey-L. These results confirm that dnMAML is an effective Notch inhibitor and combination with ELP may allow thermal targeting of the SynB1-ELP1-dnMAML complex in cancer cells while avoiding the dangers of systemic Notch inhibition.


Subject(s)
Cell-Penetrating Peptides/administration & dosage , DNA-Binding Proteins/administration & dosage , Glioblastoma/drug therapy , Receptors, Notch/antagonists & inhibitors , Transcription Factors/administration & dosage , Apoptosis/drug effects , Blood-Brain Barrier/metabolism , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell-Penetrating Peptides/pharmacology , DNA-Binding Proteins/pharmacokinetics , DNA-Binding Proteins/pharmacology , Drug Delivery Systems , Elastin/administration & dosage , Glioblastoma/pathology , Humans , Hyperthermia, Induced/methods , Peptides/administration & dosage , Transcription Factors/pharmacokinetics , Transcription Factors/pharmacology
2.
Mol Pharm ; 13(5): 1528-39, 2016 05 02.
Article in English | MEDLINE | ID: mdl-26998616

ABSTRACT

Monitoring of drug release from a heat-activated liposome carrier provides an opportunity for real-time control of drug delivery and allows prediction of the therapeutic effect. We have developed short-chain elastin-like polypeptide-incorporating thermosensitive liposomes (STLs). Here, we report the development of STL encapsulating gadobenate dimeglumine (Gd-BOPTA), a MRI contrast agent, and doxorubicin (Dox) (Gd-Dox-STL). The Dox release profile from Gd-Dox-STL was comparable to Gd-Dox-LTSL; however, the serum stability of Gd-Dox-STL was much higher than Gd-Dox-LTSL. MRI studies showed that the difference in T1 relaxation time between 37 and 42 °C for Gd-Dox-STL was larger than the difference for Gd-Dox-LTSL. Although relaxivity for both liposomes at 42 °C was similar, the relaxivity of Gd-Dox-STL at 37 °C was 2.5-fold lower than that of Gd-Dox-LTSL. This was likely due to Gd-BOPTA leakage from the LTSL because of low stability at 37 °C. Pharmacokinetic studies showed plasma half-lives of 4.85 and 1.95 h for Gd-Dox-STL and Gd-Dox-LTSL, respectively, consistent with in vitro stability data. In vivo MRI experiments demonstrated corelease of Dox and Gd-BOPTA from STL under mild hyperthermia induced by high-intensity focused ultrasound (HIFU), which suggests STL is a promising tumor selective formulation when coupled with MR-guided HIFU.


Subject(s)
Antineoplastic Agents/administration & dosage , Liposomes/administration & dosage , Animals , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Contrast Media/administration & dosage , Doxorubicin/administration & dosage , Doxorubicin/pharmacokinetics , Drug Delivery Systems/methods , Drug Liberation/physiology , Elastin/administration & dosage , Half-Life , Hot Temperature , Hyperthermia, Induced/methods , Magnetic Resonance Imaging/methods , Male , Meglumine/administration & dosage , Meglumine/analogs & derivatives , Meglumine/pharmacokinetics , Mice , Mice, Inbred BALB C , Mice, Nude , Organometallic Compounds/administration & dosage , Organometallic Compounds/pharmacokinetics , Peptides/administration & dosage , Temperature , Ultrasonography/methods
3.
Nano Lett ; 14(5): 2890-5, 2014 May 14.
Article in English | MEDLINE | ID: mdl-24738626

ABSTRACT

This paper demonstrates the first example of targeting a solid tumor that is externally heated to 42 °C by "heat seeking" drug-loaded polypeptide nanoparticles. These nanoparticles consist of a thermally responsive elastin-like polypeptide (ELP) conjugated to multiple copies of a hydrophobic cancer drug. To rationally design drug-loaded nanoparticles that exhibit thermal responsiveness in the narrow temperature range between 37 and 42 °C, an analytical model was developed that relates ELP composition and chain length to the nanoparticle phase transition temperature. Suitable candidates were designed based on the predictions of the model and tested in vivo by intravital confocal fluorescence microscopy of solid tumors, which revealed that the nanoparticles aggregate in the vasculature of tumors heated to 42 °C and that the aggregation is reversible as the temperature reverts to 37 °C. Biodistribution studies showed that the most effective strategy to target the nanoparticles to tumors is to thermally cycle the tumors between 37 and 42 °C. These nanoparticles set the stage for the targeted delivery of a range of cancer chemotherapeutics by externally applied mild hyperthermia of solid tumors.


Subject(s)
Antineoplastic Agents/chemistry , Colonic Neoplasms/drug therapy , Elastin/chemistry , Nanoparticles/chemistry , Animals , Antineoplastic Agents/administration & dosage , Cell Line, Tumor , Drug Delivery Systems , Elastin/administration & dosage , Humans , Hyperthermia, Induced , Mice , Nanoparticles/administration & dosage , Peptides/administration & dosage , Peptides/chemistry , Temperature
4.
J Control Release ; 94(2-3): 433-45, 2004 Feb 10.
Article in English | MEDLINE | ID: mdl-14744493

ABSTRACT

The objectives of this study were to evaluate: (i). the influences of hydrogel geometry, DNA molecular weight, and DNA conformation on DNA release from a silk-elastinlike protein polymer (SELP) hydrogel, (ii). the bioactivity and transfection efficiency of encapsulated DNA over time in vitro, (iii). the delivery and transfection of a reporter gene in a murine model of human breast cancer in vivo, and (iv). the in vitro release and bioactivity of adenovirus containing the green fluorescent protein (gfp) gene as a marker of gene transfer. Plasmid DNA was released from SELP hydrogels in a size-dependent manner, with the average effective diffusivity ranging from 1.70+/-0.52 x 10(-12) cm(2)/s for a larger plasmid (11 kbp) to 2.55+/-0.51 x 10(-10) cm(2)/s for a smaller plasmid (2.6 kbp). Plasmid conformation also influenced the rate of release, with the rank order linear>supercoiled>open-circular. DNA retained bioactivity in vitro, after encapsulation in a SELP hydrogel for up to 28 days. Delivery of pRL-CMV from a SELP hydrogel resulted in increased transfection in a murine model of human breast cancer by 1-3 orders of magnitude, as compared to naked DNA. The release of a bioactive adenoviral vector was related to the concentration of the polymer in the hydrogel. These studies indicate that genetically engineered SELP hydrogels have potential as matrices for controlled nonviral and viral gene delivery.


Subject(s)
Elastin/administration & dosage , Genetic Therapy/methods , Hydrogels/administration & dosage , Insect Proteins/administration & dosage , Neoplasms/drug therapy , Amino Acid Sequence , Animals , Drug Evaluation, Preclinical/methods , Elastin/pharmacokinetics , Female , Hydrogels/pharmacokinetics , Insect Proteins/pharmacokinetics , Mice , Mice, Nude , Molecular Sequence Data , Neoplasms/genetics , Plasmids/administration & dosage , Plasmids/metabolism , Plasmids/pharmacokinetics , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use , Silk , Xenograft Model Antitumor Assays/methods
5.
Peu ; 23(1): 38-42, ene. 2003. ilus, tab
Article in Es | IBECS | ID: ibc-25967

ABSTRACT

Presentamos en este trabajo un caso clínico en el que una excesiva terapia con infiltraciones de corticoides y un tratamiento ortopodológico no satisfactorio, unido a práctica deportiva excesiva, provocan que una fascitis plantar recurrente desemboque en la rotura parcial de la misma con la consecuente impotencia funcional. Planteamos así, después de un exhaustivo estudio biomecánico, un tratamiento ortopodológico personalizado junto con electroterapia como elemento coadyuvante, y siempre en coordinación con el trabajo del fisioterapeuta en aquellas alteraciones músculo-tendinosas que sin duda tienden a cronificar la patología. (AU)


Subject(s)
Adult , Male , Humans , Fascia/surgery , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/adverse effects , Infiltration-Percolation , Electric Stimulation Therapy , Orthotic Devices , Elastin/administration & dosage , Elastin/therapeutic use , Physical Therapy Specialty/methods , Physical Therapy Specialty , Fasciitis/complications , Fasciitis/diagnosis , Fasciitis/rehabilitation
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