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1.
Biochim Biophys Acta Rev Cancer ; 1879(5): 189138, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38889878

RESUMO

Head and neck cancer (HNSCC) is the 8th most common cancer in the UK, with incidence increasing due to lifestyle factors such as tobacco and alcohol abuse. HNSCC is an immune-suppressive disease characterised by impaired cytokine secretion and dysregulation of immune infiltrate. As such, immunotherapy is a potential treatment option, with therapeutic cancer vaccination demonstrating the greatest potential. The success of cancer vaccination is dependent on informed antigen selection: an ideal antigen must be either tumour-specific or tumour-associated, as well as highly immunogenic. Stratification of the patient population for antigen expression and validated biomarkers are also vital. This review focuses on the latest developments in immunotherapy, specifically the development of therapeutic vaccines, and highlights successes, potential drawbacks and areas for future development. Immunotherapy approaches considered for HNSCC include monoclonal antibodies (mAb), Oncolytic viral (OV) therapies, Immune Checkpoint Inhibitors (ICIs) and cancer vaccines.

2.
J Control Release ; 369: 63-74, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513729

RESUMO

Recent studies in colorectal cancer patients (CRC) have shown that increased resistance to thymidylate synthase (TS) inhibitors such as 5-fluorouracil (5-FU), reduce the efficacy of standard of care (SoC) treatment regimens. The nucleotide pool cleanser dUTPase is highly expressed in CRC and is an attractive target for potentiating anticancer activity of chemotherapy. The purpose of the current work was to investigate the activity of P1, P4-di(2',5'-dideoxy-5'-selenouridinyl)-tetraphosphate (P4-SedU2), a selenium-modified symmetrically capped dinucleoside with prodrug capabilities that is specifically activated by dUTPase. Using mechanochemistry, P4-SedU2 and the corresponding selenothymidine analogue P4-SeT2 were prepared with a yield of 19% and 30% respectively. The phosphate functionality facilitated complexation with the amphipathic cell-penetrating peptide RALA to produce nanoparticles (NPs). These NPs were designed to deliver P4-SedU2 intracellularly and thereby maximise in vivo activity. The NPs demonstrated effective anti-cancer activity and selectivity in the HCT116 CRC cell line, a cell line that overexpresses dUTPase; compared to HT29 CRC cells and NCTC-929 fibroblast cells which have reduced levels of dUTPase expression. In vivo studies in BALB/c SCID mice revealed no significant toxicity with respect to weight or organ histology. Pharmacokinetic analysis of blood serum showed that RALA facilitates effective delivery and rapid internalisation into surrounding tissues with NPs eliciting lower plasma Cmax than the equivalent injection of free P4-SedU2, translating the in vitro findings. Tumour growth delay studies have demonstrated significant inhibition of growth dynamics with the tumour doubling time extended by >2weeks. These studies demonstrate the functionality and action of a new pro-drug nucleotide for CRC.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Nanopartículas , Pró-Fármacos , Animais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Pró-Fármacos/uso terapêutico , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Humanos , Nanopartículas/química , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Pirofosfatases/antagonistas & inibidores , Feminino , Linhagem Celular Tumoral , Peptídeos/química , Peptídeos/administração & dosagem , Peptídeos/farmacocinética , Peptídeos/farmacologia , Camundongos Endogâmicos BALB C , Camundongos , Nucleotídeos/administração & dosagem , Nucleotídeos/química , Nucleotídeos/farmacocinética , Células HCT116
3.
Front Bioeng Biotechnol ; 10: 953887, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36420446

RESUMO

High grade serous carcinoma (HGSC) is one of the most lethal ovarian cancers that is characterised by asymptomatic tumour growth, insufficient knowledge of malignant cell origin and sub-optimal detection. HGSC has been recently shown to originate in the fallopian tube and not in the ovaries. Conventional treatments such as chemotherapy and surgery depend upon the stage of the disease and have resulted in higher rates of relapse. Hence, there is a need for alternative treatments. Differential antigen expression levels have been utilised for early detection of the cancer and could be employed in vaccination strategies using nucleic acids. In this review the different vaccination strategies in Ovarian cancer are discussed and reviewed. Nucleic acid vaccination strategies have been proven to produce a higher CD8+ CTL response alongside CD4+ T-cell response when compared to other vaccination strategies and thus provide a good arena for antitumour immune therapy. DNA and mRNA need to be delivered into the intracellular matrix. To overcome ineffective naked delivery of the nucleic acid cargo, a suitable delivery system is required. This review also considers the suitability of cell penetrating peptides as a tool for nucleic acid vaccine delivery in ovarian cancer.

4.
Biomater Adv ; 142: 213157, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36279748

RESUMO

While 2D culture presents a useful tool for cancer research, it fails to replicate the tumor microenvironment as it lacks proper three-dimensional cell-cell/cell-matrix interactions, often resulting in exaggerated responses to therapeutic agents. 3D models that aim to overcome the issues associated with 2D culture research offer a new frontier for cancer research with cell growth, morphology and genetic properties that more closely match in vivo cancers. Herein, we aim to develop a collagen-based scaffold that supports the attachment and proliferation of breast cancer (BC) cells as a 3D culture model. Scaffolds were produced on a repeatable basis using a freeze-drying procedure. The constructs were highly porous (>99%) with homogenous pore sizes (150-300 µm) and an interconnected structure. The application of 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDAC) crosslinking resulted in scaffolds with elastic moduli in the range of 1-2 kPa, mimicking cancerous breast tissue stiffness. Furthermore, the incorporation of gelatin into the scaffolds enabled the porosity, pore size and mechanical properties to be tailored, resulting in scaffolds with stiffness values that accurately replicate the stiffness of human BC extracellular matrix (ECM) (1.3-1.7 kPa). Scaffolds displayed high in vitro stability with 90% of mass remaining after 14 days of culture. The scaffolds were shown to be highly biocompatible, and capable of supporting the attachment, infiltration and proliferation of MCF7 breast cancer (BC) cells over +14 days. These results confirm the suitability of these scaffolds as culture models for BC cells. These collagen-based scaffolds offer significant potential for the exploration of aspects of BC, such as gene expression profiles and patterns, and for the assessment of the efficacy of therapeutic agents in treating BC.


Assuntos
Neoplasias da Mama , Gelatina , Humanos , Feminino , Gelatina/análise , Alicerces Teciduais/química , Neoplasias da Mama/metabolismo , Colágeno/análise , Matriz Extracelular/química , Microambiente Tumoral
5.
Pharm Res ; 39(6): 1215-1232, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35441318

RESUMO

BACKGROUND: Gene therapy via pulmonary delivery holds the potential to treat various lung pathologies. To date, spray drying has been the most promising method to produce inhalable powders. The present study determined the parameters required to spray dry nanoparticles (NPs) that contain the delivery peptide, termed RALA (N-WEARLARALARALARHLARALARALRACEA-C), complexed with plasmid DNA into a dry powder form designed for inhalation. METHODS: The spray drying process was optimised using full factorial design with 19 randomly ordered experiments based on the combination of four parameters and three centre points per block. Specifically, mannitol concentration, inlet temperature, spray rate, and spray frequency were varied to observe their effects on process yield, moisture content, a median of particle size distribution, Z-average, zeta potential, encapsulation efficiency of DNA NPs, and DNA recovery. The impact of mannitol concentration was also examined on the spray-dried NPs and evaluated via biological functionality in vitro. RESULTS: The results demonstrated that mannitol concentration was the strongest variable impacting all responses apart from encapsulation efficiency. All measured responses demonstrated a strong dependency on the experimental variables. Furthermore, spray drying with the optimal variables in combination with a low mannitol concentration (1% and 3%, w/v) produced functional RALA/pDNA NPs. CONCLUSION: The optimal parameters have been determined to spray dry RALA/pDNA NPs into an dry powder with excellent biological functionality, which have the potential to be used for gene therapy applications via pulmonary delivery.


Assuntos
Inaladores de Pó Seco , Nanopartículas , Administração por Inalação , Aerossóis/química , DNA , Inaladores de Pó Seco/métodos , Pulmão , Manitol/química , Nanopartículas/química , Tamanho da Partícula , Peptídeos , Pós/química
6.
Bioengineering (Basel) ; 10(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36671595

RESUMO

Current procedures for transdermal drug delivery (TDD) have associated limitations including poor administration of nucleic acid, small or large drug molecules, pain and stress for needle phobic people. A painless micro-sized device capable of delivering drugs easily and efficiently, eliminating the disadvantages of traditional systems, has yet to be developed. While polymeric-based microneedle (MN) arrays have been used successfully and clinically as TDD systems, these devices lack mechanical integrity, piercing capacity and the ability to achieve tailored drug release into the systemic circulation. Recent advances in micro/nano fabrication techniques using Additive Manufacturing (AM), also known as 3D printing, have enabled the fabrication of metallic MN arrays, which offer the potential to overcome the limitations of existing systems. This review summarizes the different types of MNs used in TDD and their mode of drug delivery. The application of MNs in the treatment of a range of diseases including diabetes and cancer is discussed. The potential role of solid metallic MNs in TDD, the various techniques used for their fabrication, and the influence of their geometrical characteristics (e.g., shape, size, base diameter, thickness, and tip sharpness) on effective TDD are explored. Finally, the potential and the future directions relating to the optimization of metallic MN arrays for TDD are highlighted.

7.
J Nanobiotechnology ; 19(1): 127, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33947409

RESUMO

Glioblastoma multiforme (GBM) is an incurable aggressive brain cancer in which current treatment strategies have demonstrated limited survival benefit. In recent years, nitrogen-containing bisphosphonates (N-BPs) have demonstrated direct anticancer effects in a number of tumour types including GBM. In this study, a nano-formulation with the RALA peptide was used to complex the N-BP, alendronate (ALN) into nanoparticles (NPs) < 200 nm for optimal endocytic uptake. Fluorescently labelled AlexaFluor®647 Risedronate was used as a fluorescent analogue to visualise the intracellular delivery of N-BPs in both LN229 and T98G GBM cells. RALA NPs were effectively taken up by GBM where a dose-dependent response was evidenced with potentiation factors of 14.96 and 13.4 relative to ALN alone after 72 h in LN229 and T98G cells, respectively. Furthermore, RALA/ALN NPs at the IC50, significantly decreased colony formation, induced apoptosis and slowed spheroid growth in vitro. In addition, H-Ras membrane localisation was significantly reduced in the RALA/ALN groups compared to ALN or controls, indicative of prenylation inhibition. The RALA/ALN NPs were lyophilised to enhance stability without compromising the physiochemical properties necessary for functionality, highlighting the suitability of the NPs for scale-up and in vivo application. Collectively, these data show the significant potential of RALA/ALN NPs as novel therapeutics in the treatment of GBM.


Assuntos
Antineoplásicos/farmacologia , Difosfonatos/farmacologia , Glioblastoma/tratamento farmacológico , Nanomedicina/métodos , Nitrogênio/farmacologia , Alendronato/química , Alendronato/farmacologia , Alendronato/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Difosfonatos/química , Difosfonatos/uso terapêutico , Humanos , Nanopartículas/química , Tamanho da Partícula , Peptídeos
8.
Mater Sci Eng C Mater Biol Appl ; 122: 111944, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641930

RESUMO

Collagen is the most abundant component of the extracellular matrix (ECM), therefore it represents an ideal biomaterial for the culture of a variety of cell types. Recently, collagen-based scaffolds have shown promise as 3D culture platforms for breast cancer-based research. Two-dimensional (2D) in vitro culture models, while useful for gaining preliminary insights, are ultimately flawed as they do not adequately replicate the tumour microenvironment. As a result, they do not facilitate proper 3D cell-cell/cell-matrix interactions and often an exaggerated response to therapeutic agents occurs. The ECM plays a crucial role in the development and spread of cancer. Alterations within the ECM have a significant impact on the pathogenesis of cancer, the initiation of metastasis and ultimate progression of the disease. 3D in vitro culture models that aim to replicate the tumour microenvironment have the potential to offer a new frontier for cancer research with cell growth, morphology and genetic properties that more closely match in vivo cancers. While initial 3D in vitro culture models used in breast cancer research consisted of simple hydrogel platforms, recent advances in biofabrication techniques, including freeze-drying, electrospinning and 3D bioprinting, have enabled the fabrication of biomimetic collagen-based platforms that more closely replicate the breast cancer ECM. This review highlights the current application of collagen-based scaffolds as 3D in vitro culture models for breast cancer research, specifically for adherence-based scaffolds (i.e. matrix-assisted). Finally, the future perspectives of 3D in vitro breast cancer models and their potential to lead to an improved understanding of breast cancer diagnosis and treatment are discussed.


Assuntos
Neoplasias da Mama , Mama , Neoplasias da Mama/terapia , Colágeno , Matriz Extracelular , Humanos , Alicerces Teciduais , Microambiente Tumoral
9.
J Control Release ; 330: 1288-1299, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33227336

RESUMO

The design of a non-viral gene delivery system that can release a functional nucleic acid at the intracellular destination site is an exciting but also challenging proposition. The ideal gene delivery vector must be non-toxic, non-immunogenic, overcome extra- and intra-cellular barriers, protect the nucleic acid cargo from degradation with stability over a range of temperatures. A new 15 amino acid linear peptide termed CHAT was designed in this study with the goal of delivering DNA with high efficiency into cells in vitro and tissues in vivo. Rational design involved incorporation of key amino acids including arginine for nucleic acid complexation and cellular uptake, tryptophan to enhance hydrophobic interaction with cell membranes, histidine to facilitate endosomal escape and cysteine for stability and controlled cargo release. Six linear peptides were synthesised with strategic sequences and amino acid substitutions. Data demonstrated that all six peptides complexed pDNA to produce cationic nanoparticles less than 200 nm in diameter, but not all peptides resulted in successful transfection; indicating the influence of peptide design for endosomal escape. Peptide 4, now termed CHAT, was non-cytotoxic, traversed the plasma membrane of breast and prostate cancer cell lines, and elicited reporter-gene expression following intra-tumoural and intravenous delivery in vivo. CHAT presents an exciting new peptide for the delivery of nucleic acid therapeutics.


Assuntos
Peptídeos Penetradores de Células , Técnicas de Transferência de Genes , Terapia Genética , Plasmídeos , Transfecção
10.
Biomed Mater ; 14(6): 065008, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539364

RESUMO

Using the layer-by-layer (LbL) assembly technique to deposit mechanically reinforcing coatings onto porous templates is a route for fabricating engineered bone scaffold materials with a combination of high porosity, strength, and stiffness. LbL assembly involves the sequential deposition of nano- to micro-scale multilayer coatings from aqueous solutions. Here, a design of experiments (DOE) approach was used to evaluate LbL assembly of polyethyleneimine (PEI), polyacrylic acid (PAA), and nanoclay coatings onto open-cell polyurethane foam templates. The thickness of the coatings, and the porosity, elastic modulus and collapse stress of coated foam templates were most strongly affected by the pH of PAA solutions, salt concentration, and interactions between these factors. The mechanical properties of coated foams correlated with the thickness of the coatings, but were also ascribed to changes in the coating properties due to the different assembly conditions. A DOE optimization aimed to balance the trade-off between higher mechanical properties but lower porosity of foam templates with increasing coating thickness. Micromechanical modeling predicted that deposition of 116 QLs would achieve mechanical properties of cancellous bone (>0.05 GPa stiffness and >2 MPa strength) at a suitable porosity of >70%. When capped with a final layer of PAA and cross-linked via thermal treatment, the PEI/PAA/PEI/nanoclay coatings exhibited good indirect cytotoxicity with mesenchymal stem cells. The ability of LbL assembly to deposit a wide range of functional constituents within multilayer-structured coatings makes the general strategy of templated LbL assembly a powerful route for fabricating engineered tissue scaffolds that can be applied onto various porous template materials to achieve a wide range of properties, pore structures, and multifunctionality.


Assuntos
Osso e Ossos/fisiologia , Nanocompostos/química , Engenharia Tecidual/métodos , Resinas Acrílicas/química , Animais , Antibacterianos/química , Materiais Biomiméticos/química , Células da Medula Óssea/citologia , Materiais Revestidos Biocompatíveis/química , Força Compressiva , Reagentes de Ligações Cruzadas/química , Elasticidade , Concentração de Íons de Hidrogênio , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Polietilenoimina/química , Porosidade , Estresse Mecânico , Suínos , Alicerces Teciduais/química , Titânio/química , Microtomografia por Raio-X
11.
Acta Biomater ; 96: 480-490, 2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31299353

RESUMO

Castrate resistant prostate cancer (CRPC) remains a major challenge for healthcare professionals. Immunotherapeutic approaches, including DNA vaccination, hold the potential to harness the host's own immune system to mount a cell-mediated, anti-tumour response, capable of clearing disseminated tumour deposits. These anti-cancer vaccines represent a promising strategy for patients with advanced disease, however, to date DNA vaccines have demonstrated limited efficacy in clinical trials, owing to the lack of a suitable DNA delivery system. This study was designed to evaluate the efficacy of a two-tier delivery system incorporating cationic RALA/pDNA nanoparticles (NPs) into a dissolvable microneedle (MN) patch for the purposes of DNA vaccination against prostate cancer. Application of NP-loaded MN patches successfully resulted in endogenous production of the encoded Prostate Stem Cell Antigen (PSCA). Furthermore, immunisation with RALA/pPSCA loaded MNs elicited a tumour-specific immune response against TRAMP-C1 tumours ex vivo. Finally, vaccination with RALA/pPSCA loaded MNs demonstrated anti-tumour activity in both prophylactic and therapeutic prostate cancer models in vivo. This is further evidence that this two-tier MN delivery system is a robust platform for prostate cancer DNA vaccination. STATEMENT OF SIGNIFICANCE: This research describes the development and utilisation of our unique microneedle (MN) DNA delivery system, which enables penetration through the stratum corneum and deposition of the DNA within the highly immunogenic skin layers via a dissolvable MN matrix, and facilitates cellular uptake via complexation of pDNA cargo into nanoparticles (NPs) with the RALA delivery peptide. We report for the first time on using the NP-MN platform to immunise mice with encoded Prostate Stem Cell Antigen (mPSCA) for prostate cancer DNA vaccination. Application of the NP-MN system resulted in local mPSCA expression in vivo. Furthermore, immunisation with the NP-MN system induced a tumour-specific cellular immune response, and inhibited the growth of TRAMP-C1 prostate tumours in both prophylactic and therapeutic challenge models in vivo.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Proteínas de Neoplasias/imunologia , Neoplasias de Próstata Resistentes à Castração , Vacinação , Vacinas de DNA , Animais , Vacinas Anticâncer/química , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Proteínas Ligadas por GPI/imunologia , Células HEK293 , Humanos , Masculino , Camundongos , Agulhas , Neoplasias de Próstata Resistentes à Castração/imunologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/terapia , Vacinas de DNA/química , Vacinas de DNA/imunologia , Vacinas de DNA/farmacologia
12.
Med Eng Phys ; 64: 7-14, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30638787

RESUMO

Orthopaedic surgeons often experience a mismatch between perceived intra-operative and radiographic acetabular cup orientation. This research aimed to assess the impact of pelvic orientation and surgical positioning technique on operative and radiographic cup orientation. Radiographic orientations for two surgical approaches were computationally simulated: a mechanical alignment guide and a transverse acetabular ligament approach, both in combination with different pelvic orientations. Positional errors were defined as the difference between the target radiographic orientation and that achieved. The transverse acetabular ligament method demonstrated smaller positional errors for radiographic version; 4.0° ±â€¯2.9° as compared to 9.4° ±â€¯7.3° for the mechanical alignment guide method. However, both methods resulted in similar errors in radiographic inclination. Multiple regression analysis showed that intraoperative pelvic rotation about the anterior-posterior axis was a strong predictor for these errors (BTAL = -0.893, BMAG = -0.951, p < 0.01). Application of the transverse acetabular ligament method can reduce errors in radiographic version. However, if the orthopaedic surgeon is referencing off the theatre floor to control inclination when operating in lateral decubitus, this is only reliable if the pelvic sagittal plane is horizontal. There is currently no readily available method for ensuring that this is the case during total hip replacement surgery.


Assuntos
Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Artroplastia de Quadril , Fenômenos Mecânicos , Pelve/diagnóstico por imagem , Pelve/cirurgia , Tomografia Computadorizada por Raios X , Período Intraoperatório , Erros Médicos
13.
Hip Int ; 29(1): 89-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29783888

RESUMO

INTRODUCTION:: Acetabular cup orientation during total hip arthroplasty (THA) remains a challenge. This is influenced by patient positioning during surgery and the method used to orientate the acetabular cup. The aim of this study was to assess current UK practice for patient positioning and cup orientation, particularly with respect to patient supports and techniques used to achieve target version and inclination. METHODS:: A literature review and pilot study were initially conducted to develop the questionnaire, which was completed by British Hip Society members ( n = 183). As the majority of THA surgical procedures within the UK are performed with the patient in lateral decubitus, orthopaedic surgeons who operated with the patient in the supine position were excluded ( n = 18); a further 6% were incomplete and also excluded ( n = 11). RESULTS:: Of those who operated in lateral decubitus, 76.6% ( n = 118/154) used the posterior approach. Only 31% ( n = 47/154) considered their supports to be completely rigid. More than 35% ( n = 55/154) were unhappy with the supports that they presently use. The most common methods for controlling operative inclination and version were a mechanical alignment guide (MAG; n = 78/154; 50.6%) and the transverse acetabular ligament (TAL; n = 82/154; 53.2%); 31.2% (48/154) used a freehand technique to control operative inclination. CONCLUSION:: Limited studies have been conducted whereby patient supports have been analysed and key design principles outlined. With 35.7% of the orthopaedic surgeons surveyed having issues with their current supports, a greater awareness of essential characteristics for patient supports is required.


Assuntos
Artroplastia de Quadril/métodos , Prótese de Quadril , Posicionamento do Paciente , Padrões de Prática Médica , Acetábulo/cirurgia , Idoso , Artroplastia de Quadril/instrumentação , Feminino , Humanos , Ligamentos Articulares/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários , Reino Unido
14.
Cancer Nanotechnol ; 9(1): 5, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29899810

RESUMO

BACKGROUND: Recent approvals of gene therapies by the FDA and the EMA for treatment of inherited disorders have further opened the door for assessment of nucleic acid pharmaceuticals for clinical usage. Arising from the presence of damaged or inappropriate DNA, cancer is a condition particularly suitable for genetic intervention. The RALA peptide has been shown to be a potent non-viral delivery platform for nucleic acids. This study examines the use of RALA to deliver a plasmid encoding inducible nitric oxide synthase (iNOS) as an anti-cancer treatment. METHODS: The physiochemical properties of the RALA/DNA nanoparticles were characterized via dynamic light scattering and transmission electron microscopy. The nanoparticles were labelled with fluorophores and tracked over time using confocal microscopy with orthogonal sections to determine cellular location. In vitro studies were employed to determine functionality of the nanoparticles both for pEGFP-N1 and CMV-iNOS. Nanoparticles were injected intravenously into C57/BL6 mice with blood and serum samples analysed for immune response. PC3-luc2M cells were injected into the left ventricle of SCID mice followed by treatment with RALA/CMV-iNOS nanoparticles to evaluate the tumour response in a metastatic model of prostate cancer. RESULTS: Functional cationic nanoparticles were produced with gene expression in PC-3 prostate cancer cells. Furthermore, repeated administrations of RALA/DNA nanoparticles into immunocompetent mice did not produce any immunological response: neutralization of the vector or release of inflammatory mediators. RALA/CMV-iNOS reduced the clonogenicity of PC-3 cells in vitro, and in an in vivo model of prostate cancer metastasis, systemically delivered RALA/CMV-iNOS significantly improved the survival of mice. CONCLUSION: These studies further validate RALA as a genetic cargo delivery vehicle and iNOS as a potent therapy for the treatment of cancer.

15.
Eur J Pharm Biopharm ; 127: 288-297, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29510205

RESUMO

Dissolvable microneedles can be employed to deliver DNA to antigen presenting cells within the skin. However, this technology faces two main challenges: the poor transfection efficacy of pDNA following release from the microneedle matrix, and the limited loading capacity of the micron-scale devices. Two-tier delivery systems combining microneedle platforms and DNA delivery vectors have increased efficacy but the challenge of increasing the loading capacity remains. This study utilised lyophilisation to increase the loading of RALA/pDNA nanoparticles within dissolvable PVA microneedles. As a result, delivery was significantly enhanced in vivo into an appropriate range for DNA vaccination (∼50 µg per array). Furthermore, modifying the manufacturing process was not detrimental to the microneedle mechanical properties or cargo functionality. It was demonstrated that arrays retained mechanical and functional stability over short term storage, and were able to elicit gene expression in vitro and in vivo. Finally, treatment with this novel formulation significantly retarded the growth of established tumours, and proved superior to standard intramuscular injection in a preclinical model of cervical cancer.


Assuntos
DNA/administração & dosagem , DNA/química , Peptídeos/química , Neoplasias do Colo do Útero/tratamento farmacológico , Vacinas de DNA/administração & dosagem , Vacinas de DNA/química , Animais , Plásticos Biodegradáveis/química , Linhagem Celular , Sistemas de Liberação de Medicamentos/métodos , Feminino , Técnicas de Transferência de Genes , Terapia Genética/métodos , Injeções Intramusculares/métodos , Camundongos , Camundongos Endogâmicos C57BL , Microinjeções/métodos , Nanopartículas/química , Agulhas , Plasmídeos/administração & dosagem , Pele/metabolismo , Suínos , Transfecção/métodos , Vacinação/métodos
16.
Macromol Biosci ; 17(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28714139

RESUMO

In this study, thermoresponsive copolymers that are fully injectable, biocompatible, and biodegradable and are synthesized via graft copolymerization of poly(N-isopropylacrylamide) onto alginate using a free-radical reaction are presented. This new synthesis method does not involve multisteps or associated toxicity issues, and has the potential to reduce scale-up difficulties. Chemical and physical analyses verify the resultant graft copolymer structure. The lower critical solution temperature, which is a characteristic of sol-gel transition, is observed at 32 °C. The degradation properties indicate suitable degradation kinetics for drug delivery and bone tissue engineering applications. The synthesized P(Alg-g-NIPAAm) hydrogel is noncytotoxic with both human osteosarcoma (MG63) cells and porcine bone marrow derived mesenchymal stem cells (pBMSCs). pBMSCs encapsulated in the P(Alg-g-NIPAAm) hydrogel remain viable, show uniform distribution within the injected hydrogel, and undergo osteogenic and chondrogenic differentiation under appropriate culture conditions. Furthermore, for the first time, this work will explore the influence of alginate viscosity on the viscoelastic properties of the resulting copolymer hydrogels, which influences the rate of medical device formation and subsequent drug release. Together the results of this study indicate that the newly synthesized P(Alg-g-NIPAAm) hydrogel has potential to serve as a versatile and improved injectable platform for drug delivery and bone tissue engineering applications.


Assuntos
Acrilamidas/química , Alginatos/química , Materiais Biocompatíveis/administração & dosagem , Hidrogéis/química , Injeções , Transplante de Células-Tronco Mesenquimais , Polimerização , Temperatura , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Células-Tronco Mesenquimais/citologia , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Viscosidade
17.
Mol Ther Nucleic Acids ; 6: 249-258, 2017 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-28325291

RESUMO

This study aimed to determine the therapeutic benefit of a nanoparticular formulation for the delivery of inducible nitric oxide synthase (iNOS) gene therapy in a model of breast cancer metastasis. Nanoparticles comprising a cationic peptide vector, RALA, and plasmid DNA were formulated and characterized using a range of physiochemical analyses. Nanoparticles complexed using iNOS plasmids and RALA approximated 60 nm in diameter with a charge of 25 mV. A vector neutralization assay, performed to determine the immunogenicity of nanoparticles in immunocompetent C57BL/6 mice, revealed that no vector neutralization was evident. Nanoparticles harboring iNOS plasmids (constitutively active cytomegalovirus [CMV]-driven or transcriptionally regulated human osteocalcin [hOC]-driven) evoked iNOS protein expression and nitrite accumulation and impaired clonogenicity in the highly aggressive MDA-MB-231 human breast cancer model. Micrometastases of MDA-MB-231-luc-D3H1 cells were established in female BALB/c SCID mice by intracardiac delivery. Nanoparticulate RALA/CMV-iNOS or RALA/hOC-iNOS increased median survival in mice bearing micrometastases by 27% compared with controls and also provoked elevated blood nitrite levels. Additionally, iNOS gene therapy sensitized MDA-MB-231-luc-D3H1 tumors to docetaxel treatment. Studies demonstrated that systemically delivered RALA-iNOS nanoparticles have therapeutic potential for the treatment of metastatic breast cancer. Furthermore, detection of nitrite levels in the blood serves as a reliable biomarker of treatment.

18.
Nanomedicine ; 13(3): 921-932, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27979747

RESUMO

HPV subtypes (16, 18) are associated with the development of cervical cancer, with oncoproteins E6 and E7 responsible for pathogenesis. The goal of this study was to evaluate our 'smart system' technology platform for DNA vaccination against cervical cancer. The vaccination platform brings together two main components; a peptide RALA which condenses DNA into cationic nanoparticles (NPs), and a polymeric polyvinylpyrrolidone (PVP) microneedle (MN) patch for cutaneous delivery of the loaded NPs. RALA condensed E6/E7 DNA into NPs not exceeding 100nm in diameter, and afforded the DNA protection from degradation in PVP. Sera from mice vaccinated with MN/RALA-E6/E7 were richer in E6/E7-specific IgGs, displayed a greater T-cell-mediated TC-1 cytotoxicity and contained more IFN-γ than sera from mice that received NPs intramuscularly. More importantly, MN/RALA-E6/E7 delayed TC-1 tumor initiation in a prophylactic model, and slowed tumor growth in a therapeutic model of vaccination, and was more potent than intramuscular vaccination.


Assuntos
Vacinas Anticâncer/administração & dosagem , Técnicas de Transferência de Genes/instrumentação , Oligopeptídeos/química , Infecções por Papillomavirus/prevenção & controle , Povidona/química , Neoplasias do Colo do Útero/prevenção & controle , Vacinação/instrumentação , Vacinas de DNA/administração & dosagem , Administração Cutânea , Animais , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Linhagem Celular , Colo do Útero/imunologia , Colo do Útero/patologia , Colo do Útero/virologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/imunologia , Humanos , Imunidade Humoral , Camundongos Endogâmicos C57BL , Agulhas , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/imunologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Proteínas Repressoras/genética , Proteínas Repressoras/imunologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Vacinas de DNA/uso terapêutico
19.
Expert Opin Ther Targets ; 20(9): 1075-85, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26942553

RESUMO

INTRODUCTION: Development of a therapy for bone metastases is of paramount importance for castration-resistant prostate cancer (CRPC). The osteomimetic properties of CRPC confer a propensity to metastasize to osseous sites. Micro-ribonucleic acid (miRNA) is non-coding RNA that acts as a post-transcriptional regulator of multiple proteins and associated pathways. Therefore identification of miRNAs could reveal a valid third generation therapy for CRPC. AREAS COVERED: miR34a has been found to play an integral role in the progression of prostate cancer, particularly in the regulation of metastatic genes involved in migration, intravasation, extravasation, bone attachment and bone homeostasis. The correlation between miR34a down-regulation and metastatic progression has generated substantial interest in this field. EXPERT OPINION: Examination of the evidence reveals that miR34a is an ideal target for gene therapy for metastatic CRPC. We also conclude that future studies should focus on the effects of miR34a upregulation in CRPC with respect to migration, translocation to bone micro-environment and osteomimetic phenotype development. The success of miR34a as a therapeutic is reliant on the development of appropriate delivery systems and targeting to the bone micro-environment. In tandem with any therapeutic studies, biomarker serum levels should also be ascertained as an indicator of successful miR34a delivery.


Assuntos
Neoplasias Ósseas/terapia , MicroRNAs/genética , Neoplasias de Próstata Resistentes à Castração/terapia , Animais , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Progressão da Doença , Regulação para Baixo , Terapia Genética/métodos , Humanos , Masculino , MicroRNAs/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/genética , Microambiente Tumoral
20.
Int J Pharm ; 500(1-2): 144-53, 2016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26802497

RESUMO

Designer biopolymers (DBPs) represent state of the art genetically engineered biomacromolecules designed to condense plasmid DNA, and overcome intra- and extra- cellular barriers to gene delivery. Three DBPs were synthesized, each with the tumor molecular targeting peptide-1 (TMTP-1) motif to specifically target metastases. Each DBP was complexed with a pEGFP-N1 reporter plasmid to permit physiochemical and biological assay analysis. Results indicated that two of the biopolymers (RMHT and RM3GT) effectively condensed pEGFP-N1 into cationic nanoparticles <100 nm and were capable of transfecting PC-3 metastatic prostate cancer cells. Conversely the anionic RMGT DBP nanoparticles could not transfect PC-3 cells. RMHT and RM3GT nanoparticles were stable in the presence of serum and protected the cargo from degradation. Additionally it was concluded that cell viability could recover post-transfection with these DBPs, which were less toxic than the commercially available transfection reagent Lipofectamine(®) 2000. With both DBPs, a higher transfection efficacy was observed in PC-3 cells than in the moderately metastatic, DU145, and normal, PNT2-C2, cell lines. Blocking of the TMTP-1 receptors inhibited gene transfer indicating internalization via this receptor. In conclusion RMHT and RM3GT are fully functional DBPs that address major obstacles to gene delivery and target metastatic cells expressing the TMTP-1 receptor.


Assuntos
Biopolímeros/administração & dosagem , DNA/administração & dosagem , Técnicas de Transferência de Genes , Nanopartículas/administração & dosagem , Oligopeptídeos/metabolismo , Biopolímeros/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , DNA/química , Proteínas de Fluorescência Verde/genética , Humanos , Masculino , Nanopartículas/química , Plasmídeos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo
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