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1.
ACS Nano ; 18(15): 10439-10453, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38567994

RESUMO

The cGAS-STING pathway plays a crucial role in innate immune activation against cancer and infections, and STING agonists based on cyclic dinucleotides (CDN) have garnered attention for their potential use in cancer immunotherapy and vaccines. However, the limited drug-like properties of CDN necessitate an efficient delivery system to the immune system. To address these challenges, we developed an immunostimulatory delivery system for STING agonists. Here, we have examined aqueous coordination interactions between CDN and metal ions and report that CDN mixed with Zn2+ and Mn2+ formed distinctive crystal structures. Further pharmaceutical engineering led to the development of a functional coordination nanoparticle, termed the Zinc-Mn-CDN Particle (ZMCP), produced by a simple aqueous one-pot synthesis. Local or systemic administration of ZMCP exerted robust antitumor efficacy in mice. Importantly, recombinant protein antigens from SARS-CoV-2 can be simply loaded during the aqueous one-pot synthesis. The resulting ZMCP antigens elicited strong cellular and humoral immune responses that neutralized SARS-CoV-2, highlighting ZMCP as a self-adjuvant vaccine platform against COVID-19 and other infectious pathogens. Overall, this work establishes a paradigm for developing translational coordination nanomedicine based on drug-metal ion coordination and broadens the applicability of coordination medicine for the delivery of proteins and other biologics.


Assuntos
Nanopartículas , Neoplasias , Vacinas , Animais , Camundongos , Neoplasias/terapia , Adjuvantes Imunológicos , Imunoterapia/métodos , Nanopartículas/química
2.
J Control Release ; 357: 84-93, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36948420

RESUMO

Cyclic dinucleotides (CDNs), as one type of Stimulator of Interferon Genes (STING) pathway agonist, have shown promising results for eliciting immune responses against cancer and viral infection. However, the suboptimal drug-like properties of conventional CDNs, including their short in vivo half-life and poor cellular permeability, compromise their therapeutic efficacy. In this study, we have developed a manganese-silica nanoplatform (MnOx@HMSN) that enhances the adjuvant effects of CDN by achieving synergy with Mn2+ for vaccination against cancer and SARS-CoV-2. MnOx@HMSN with large mesopores were efficiently co-loaded with CDN and peptide/protein antigens. MnOx@HMSN(CDA) amplified the activation of the STING pathway and enhanced the production of type-I interferons and other proinflammatory cytokines from dendritic cells. MnOx@HMSN(CDA) carrying cancer neoantigens elicited robust antitumor T-cell immunity with therapeutic efficacy in two different murine tumor models. Furthermore, MnOx@HMSN(CDA) loaded with SARS-CoV-2 antigen achieved strong and durable (up to one year) humoral immune responses with neutralizing capability. These results demonstrate that MnOx@HMSN(CDA) is a versatile nanoplatform for vaccine applications.


Assuntos
COVID-19 , Neuropatia Hereditária Motora e Sensorial , Nanopartículas , Vacinas , Humanos , Animais , Camundongos , Manganês , Dióxido de Silício , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoterapia
3.
BMC Med Imaging ; 22(1): 122, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35799139

RESUMO

BACKGROUND: To assess the feasibility of biventricular SAPPHIRE T1 mapping in vivo across field strengths using diastolic, systolic and dark-blood (DB) approaches. METHODS: 10 healthy volunteers underwent same-day non-contrast cardiovascular magnetic resonance at 1.5 Tesla (T) and 3 T. Left and right ventricular (LV, RV) T1 mapping was performed in the basal, mid and apical short axis using 4-variants of SAPPHIRE: diastolic, systolic, 0th and 2nd order motion-sensitized DB and conventional modified Look-Locker inversion recovery (MOLLI). RESULTS: LV global myocardial T1 times (1.5 T then 3 T results) were significantly longer by diastolic SAPPHIRE (1283 ± 11|1600 ± 17 ms) than any of the other SAPPHIRE variants: systolic (1239 ± 9|1595 ± 13 ms), 0th order DB (1241 ± 10|1596 ± 12) and 2nd order DB (1251 ± 11|1560 ± 20 ms, all p < 0.05). In the mid septum MOLLI and diastolic SAPPHIRE exhibited significant T1 signal contamination (longer T1) at the blood-myocardial interface not seen with the other 3 SAPPHIRE variants (all p < 0.025). Additionally, systolic, 0th order and 2nd order DB SAPPHIRE showed narrower dispersion of myocardial T1 times across the mid septum when compared to diastolic SAPPHIRE (interquartile ranges respectively: 25 ms, 71 ms, 73 ms vs 143 ms, all p < 0.05). RV T1 mapping was achievable using systolic, 0th and 2nd order DB SAPPHIRE but not with MOLLI or diastolic SAPPHIRE. All 4 SAPPHIRE variants showed excellent re-read reproducibility (intraclass correlation coefficients 0.953 to 0.996). CONCLUSION: These small-scale preliminary healthy volunteer data suggest that DB SAPPHIRE has the potential to reduce partial volume effects at the blood-myocardial interface, and that systolic SAPPHIRE could be a feasible solution for right ventricular T1 mapping. Further work is needed to understand the robustness of these sequences and their potential clinical utility.


Assuntos
Óxido de Alumínio , Interpretação de Imagem Assistida por Computador , Frequência Cardíaca , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
4.
Eur Heart J Qual Care Clin Outcomes ; 8(3): 289-297, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-34849707

RESUMO

AIMS: To explore the impact of incorporating a faster cardiac magnetic resonance (CMR) imaging protocol in a low-middle-income country (LMIC) and using the result to guide chelation in transfusion-dependent patients. METHODS AND RESULTS: A prospective UK-India collaborative cohort study was conducted in two cities in India. Two visits 13 months apart included clinical assessment and chelation therapy recommendations based on rapid CMR results. Participants were recruited by the local patient advocate charity, who organized the patient medical camps. The average scanning time was 11.3 ± 2.5 min at the baseline and 9.8 ± 2.4 min (P < 0.001) at follow-up. The baseline visit was attended by 103 patients (mean age 25 years) and 83% attended the second assessment. At baseline, 29% had a cardiac T2* < 20 ms, which represents significant iron loading, and 12% had left ventricular ejection fraction <60%, the accepted lower limit in this population. Only 3% were free of liver iron (T2* ≥ 17 ms). At 13 months, more patients were taking intensified dual chelation therapy (43% vs. 55%, P = 0.002). In those with cardiac siderosis (baseline T2* < 20 ms), there was an improvement in T2*-10.9 ± 5.9 to 13.5 ± 8.7 ms, P = 0.005-and fewer were classified as having clinically important cardiac iron loading (T2* < 20 ms, 24% vs. 16%, P < 0.001). This is the first illustration in an LMIC that incorporating CMR results into patient management plans can improve cardiac iron loading. CONCLUSION: For thalassaemia patients in an LMIC, a simplified CMR protocol linked to therapeutic recommendation via the patient camp model led to enhanced chelation therapy and a reduction in cardiac iron in 1 year.


Assuntos
Talassemia , Talassemia beta , Adulto , Terapia por Quelação/métodos , Estudos de Coortes , Humanos , Ferro , Imageamento por Ressonância Magnética , Estudos Prospectivos , Volume Sistólico , Talassemia/terapia , Função Ventricular Esquerda , Talassemia beta/patologia , Talassemia beta/terapia
5.
Acc Chem Res ; 53(10): 2094-2105, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33017150

RESUMO

The immune system has evolved over time to protect the host from foreign microorganisms. Activation of the immune system is predicated on a distinction between self and nonself. Unfortunately, cancer is characterized by genetic alterations in the host's cells, leading to uncontrolled cellular proliferation and evasion of immune surveillance. Cancer immunotherapy aims to educate the host's immune system to not only recognize but also attack and kill mutated cancer cells. While immune checkpoint blockers have been proven to be effective against multiple types of advanced cancer, the overall patient response rate still remains below 30%. Therefore, there is an urgent need to improve current cancer immunotherapies. In this Account, we present an overview of our recent progress on nanoparticle-based strategies for improving cancer vaccines and immunotherapies. We also present other complementary strategies to give a well-rounded snapshot of the field of combination cancer immunotherapy. The versatility and tunability of nanoparticles make them promising platforms for addressing individual challenges posed by various cancers. For example, nanoparticles can deliver cargo materials to specific cells, such as vaccines delivered to antigen-presenting cells for strong immune activation. Nanoparticles also allow for stimuli-responsive delivery of various therapeutics to cancer cells, thus forming the basis for combination cancer immunotherapy. Here, we focus on nanoparticle platforms engineered to deliver tumor antigens, whole tumor cells, and chemotherapeutic or phototherapeutic agents in a manner to effectively and safely trigger the host's immune system against tumor cells. For each work, we discuss the nanoparticle platform developed, synthesis chemistry, and in vivo applications. Nanovaccines offer a unique platform for codelivery of personalized tumor neoantigens and adjuvants and elicitation of robust immune responses against aggressive tumors. Nanovaccines either delivering whole tumor cell lysate or formed from tumor cell lysate may increase the repertoire of tumor antigens as immune targets while exploiting immunogenic cell death to prime antitumor immune responses. We also discuss how antigen- and whole tumor cell-based approaches may open the door for personalized cancer vaccination and immunotherapy. On the other hand, chemotherapy, phototherapy, and radiotherapy are more standardized cancer therapies, and nanoparticle-based approaches may promote their ability to initiate T cell activation against tumor cells and improve antitumor efficacy with minimal toxicity. Finally, building on the recent progress in nanoparticle-based cancer immunotherapy, the field should set the ultimate goal to be clinical translation and clinical efficacy. We will discuss regulatory, analytical, and manufacturing hurdles that should be addressed to expedite the clinical translation of nanomedicine-based cancer immunotherapy.


Assuntos
Vacinas Anticâncer/administração & dosagem , Imunoterapia , Nanopartículas/química , Neoplasias/terapia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígenos de Neoplasias/química , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/química , Vacinas Anticâncer/imunologia , Grafite/química , Humanos , Neoplasias/imunologia , Neoplasias/prevenção & controle , Polímeros/química
6.
BMJ Open ; 10(1): e034399, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31969369

RESUMO

INTRODUCTION: Arterial stiffness and left ventricular (LV) hypertrophy are the key markers of hypertensive target organ damage (TOD) associated with increased cardiovascular morbidity and mortality. We have previously shown that dietary inorganic nitrate supplementation lowers blood pressure (BP) in hypertension, however, whether this approach might also improve markers of hypertensive TOD is unknown. In this study, we will investigate whether daily dietary inorganic nitrate administration reduces LV mass and improves measures of arterial stiffness. METHODS AND DESIGN: NITRATE-TOD is a double-blind, randomised, single-centre, placebo-controlled phase II trial aiming to enrol 160 patients with suboptimal BP control on one or more antihypertensives. Patients will be randomised to receive 4 months once daily dose of either nitrate-rich beetroot juice or nitrate-deplete beetroot juice (placebo). The primary outcomes are reduction in LV mass and reduction in pulse wave velocity (PWV) and central BP.The study has a power of 95% for detecting a 9 g LV mass change by cardiovascular MRI (~6% change for a mildly hypertrophied heart of 150 g). For PWV, we have a power of >95% for detecting a 0.6 m/s absolute change. For central systolic BP, we have a>90% power to detect a 5.8 mm Hg difference in central systolic BP.Secondary end points include change in ultrasound flow-mediated dilation, change in plasma nitrate and nitrite concentration and change in BP. ETHICS AND DISSEMINATION: The study was approved by the London-City and East Research Ethics Committee (10/H0703/98). Trial results will be published according to the Consolidated Standards of Reporting Trials statement and will be presented at conferences and reported in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03088514.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Nitratos/uso terapêutico , Rigidez Vascular/efeitos dos fármacos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Reino Unido , Adulto Jovem
7.
JACC Cardiovasc Imaging ; 13(1 Pt 1): 44-54, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31103587

RESUMO

OBJECTIVES: Because risk stratification data represents a key domain of biomarker validation, we compared associations between outcomes and various cardiovascular magnetic resonance (CMR) metrics quantifying myocardial fibrosis (MF) in noninfarcted myocardium: extracellular volume fraction (ECV), native T1, post-contrast T1, and partition coefficient. BACKGROUND: MF associates with vulnerability to adverse events (e.g., mortality and hospitalization for heart failure [HHF]), but investigators still debate its optimal measurement; most histological validation data show strongest ECV correlations with MF. METHODS: We enrolled 1,714 consecutive patients without amyloidosis or hypertrophic cardiomyopathy from a single CMR referral center serving an integrated healthcare network. We measured T1 (MOdified Look-Locker Inversion recovery [MOLLI]) in nonenhanced myocardium, averaged from 2 short-axis slices (basal and mid) before and 15 to 20 min after a gadolinium contrast bolus. We compared chi-square test values from CMR MF measures in univariable and multivariable Cox regression models. We assessed "dose-response" relationships in Kaplan-Meier curves using log-rank statistics for quartile strata. We also computed net reclassification improvement (NRI) and integrated discrimination improvement (IDI for Cox models with ECV vs. native T1). RESULTS: Over a median of 5.6 years, 374 events occurred after CMR (162 HHF events and 279 deaths, 67 with both). ECV yielded the best separation of Kaplan-Meier curves and the highest log-rank statistics. In univariable and multivariable models, ECV associated most strongly with outcomes, demonstrating the highest chi-square test values. Native T1 or post-contrast T1 did not associate with outcomes in the multivariable model. ECV provided added prognostic value to models with native T1, for example, in multivariable models IDI = 0.0037 (95% confidence interval [CI]: 0.0009 to 0.0071), p = 0.02; NRI = 0.151 (95% CI: 0.022 to 0.292), p = 0.04. CONCLUSIONS: Analogous to histological previously published validation data, ECV myocardial fibrosis measures exhibited more robust associations with outcomes than other surrogate CMR MF measures. Superior risk stratification by ECV supports claims that ECV optimally measures MF in noninfarcted myocardium.


Assuntos
Amiloidose/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Volume Sistólico , Função Ventricular Esquerda , Remodelação Ventricular , Idoso , Amiloidose/mortalidade , Amiloidose/patologia , Amiloidose/fisiopatologia , Cardiomiopatia Hipertrófica/mortalidade , Cardiomiopatia Hipertrófica/patologia , Cardiomiopatia Hipertrófica/fisiopatologia , Meios de Contraste/administração & dosagem , Progressão da Doença , Feminino , Fibrose , Gadolínio/administração & dosagem , Compostos Heterocíclicos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/administração & dosagem , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco
8.
ACS Nano ; 13(10): 12148-12161, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31556987

RESUMO

Photodynamic therapy (PDT) is an effective, noninvasive therapeutic modality against local tumors that are accessible to the source of light. However, it remains challenging to apply PDT for the treatment of disseminated, metastatic cancer. On the other hand, cancer immunotherapy offers a promising approach for generating systemic antitumor immune responses against disseminated cancer. Here we report a multifunctional nanomaterial system for the combination of PDT and personalized cancer immunotherapy and demonstrate their potency against local as well as disseminated tumors. Specifically, we have synthesized uniform and biodegradable mesoporous silica nanoparticles (bMSN) with an average size of ∼80 nm and large pore size of 5-10 nm for theranostic positron emission tomography (PET)-guided PDT and neoantigen-based cancer vaccination. Multiple neoantigen peptides, CpG oligodeoxynucleotide adjuvant, and photosensitizer chlorin e6 were coloaded into a bMSN nanoplatform, and PET imaging revealed effective accumulation of bMSN in tumors (up to 9.0% ID/g) after intravenous administration. Subsequent PDT with laser irradiation recruited dendritic cells to PDT-treated tumor sites and elicited neoantigen-specific, tumor-infiltrating cytotoxic T-cell lymphocytes. Using multiple murine models of bilateral tumors, we demonstrate strong antitumor efficacy of PDT-immunotherapy against locally treated tumors as well as distant, untreated tumors. Our findings suggest that the bMSN is a promising platform for combining imaging and PDT-enhanced personalized immunotherapy for the treatment of advanced cancer.


Assuntos
Nanopartículas/química , Fotoquimioterapia/métodos , Tomografia por Emissão de Pósitrons/métodos , Dióxido de Silício/química , Porosidade
9.
Nat Biomed Eng ; 3(10): 768-782, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31406259

RESUMO

Research into the immunological processes implicated in cancer has yielded a basis for the range of immunotherapies that are now considered the fourth pillar of cancer treatment (alongside surgery, radiotherapy and chemotherapy). For some aggressive cancers, such as advanced non-small-cell lung carcinoma, combination immunotherapies have resulted in unprecedented treatment efficacy for responding patients, and have become frontline therapies. Individualized immunotherapy, enabled by the identification of patient-specific mutations, neoantigens and biomarkers, and facilitated by advances in genomics and proteomics, promises to broaden the responder patient population. In this Perspective, we give an overview of immunotherapies leveraging engineering approaches, including the design of biomaterials, delivery strategies and nanotechnology solutions, for the realization of individualized cancer treatments such as nanoparticle vaccines customized with neoantigens, cell therapies based on patient-derived dendritic cells and T cells, and combinations of theranostic strategies. Developments in precision cancer immunotherapy will increasingly rely on the adoption of engineering principles.


Assuntos
Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/imunologia , Vacinas Anticâncer/imunologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Imunoterapia/métodos , Medicina de Precisão/métodos , Algoritmos , Animais , Antígenos de Neoplasias/genética , Antineoplásicos , Biomarcadores Tumorais/genética , Vacinas Anticâncer/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Terapia Baseada em Transplante de Células e Tecidos , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Tratamento Farmacológico , Quimioterapia Combinada , Vetores Genéticos , Humanos , Mutação , Nanopartículas , Nanotecnologia , Fototerapia , Linfócitos T/imunologia , Nanomedicina Teranóstica , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
10.
Ann Lab Med ; 38(5): 395-401, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29797808

RESUMO

Mitochondria are the powerhouses of the cell as well as the primary site of hematopoiesis, which also occurs in the cytoplasm. Hematopoietic stem cells (HSCs) are characterized by a very high turnover rate, and are thus considered to be relatively free from the age-related insults generated by mitochondria. However, HSCs are also subject to these age-related insults, including the incidence of myeloid proliferative diseases, marrow failure, hematopoietic neoplasms, and deterioration of the adaptive human immune system. Recently, NAD⁺ dietary supplements, known as niacin or vitamin B3, including tryptophan, nicotinic acid, nicotinamide, and the newly identified NAD⁺ precursor nicotinamide riboside, have been shown to play a role in restoring adult stem cell function through the amelioration of mitochondrial dysfunction. This insight motivated a study that focused on reversing aging-related cellular dysfunction in adult mouse muscle stem cells by supplementing their diet with nicotinamide riboside. The remedial effect of nicotinamide riboside enhanced mitochondrial function in these muscle stem cells in a SIRT1-dependent manner, affecting cellular respiration, membrane potential, and production of ATP. Accordingly, numerous studies have demonstrated that sirtuins, under nuclear/mitochondrial control, have age-specific effects in determining HSC phenotypes. Based on the evidence accumulated thus far, we propose a clinical intervention for the restoration of aged HSC function by improving mitochondrial function through NAD⁺ precursor supplementation.


Assuntos
Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Senescência Celular/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Mitocôndrias/genética , NAD/metabolismo , Niacina/farmacologia , Niacinamida/farmacologia , Sirtuínas/metabolismo
11.
Nat Commun ; 9(1): 1074, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29540781

RESUMO

Photothermal therapy (PTT) is a promising cancer treatment modality, but PTT generally requires direct access to the source of light irradiation, thus precluding its utility against disseminated, metastatic tumors. Here, we demonstrate that PTT combined with chemotherapy can trigger potent anti-tumor immunity against disseminated tumors. Specifically, we have developed polydopamine-coated spiky gold nanoparticles as a new photothermal agent with extensive photothermal stability and efficiency. Strikingly, a single round of PTT combined with a sub-therapeutic dose of doxorubicin can elicit robust anti-tumor immune responses and eliminate local as well as untreated, distant tumors in >85% of animals bearing CT26 colon carcinoma. We also demonstrate their therapeutic efficacy against TC-1 submucosa-lung metastasis, a highly aggressive model for advanced head and neck squamous cell carcinoma (HNSCC). Our study sheds new light on a previously unrecognized, immunological facet of chemo-photothermal therapy and may lead to new therapeutic strategies against advanced cancer.


Assuntos
Terapia Combinada/métodos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/terapia , Fototerapia/métodos , Animais , Linhagem Celular Tumoral , Doxorrubicina/uso terapêutico , Quimioterapia Combinada , Humanos , Fotoquimioterapia/métodos
12.
Biomaterials ; 165: 56-65, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29501970

RESUMO

Mesoporous silica nanoshell (MSN) coating has been demonstrated as a versatile surface modification strategy for various kinds of inorganic functional nanoparticles, such as gold nanorods (GNRs), to achieve not only improved nanoparticle stability but also concomitant drug loading capability. However, limited drug loading capacity and low tumor accumulation rate in vivo are two major challenges for the biomedical applications of MSN-coated GNRs (GNR@MSN). In this study, by coating uniformly sized GNRs with MSN in an oil-water biphase reaction system, we have successfully synthesized a new bacteria-like GNR@MSN (i.e., bGNR@MSN) with a significantly enlarged pore size (4-8 nm) and surface area (470 m2/g). After PEGylation and highly efficient loading of doxorubicin (DOX, 40.9%, w/w), bGNR@MSN were used for positron emission tomography (PET, via facile and chelator-free 89Zr-labeling) and photoacoustic imaging-guided chemo-photothermal cancer therapy in vivo. PET imaging showed that 89Zr-labeled bGNR@MSN(DOX)-PEG can passively target to the 4T1 murine breast cancer-bearing mice with high efficiency (∼10 %ID/g), based on enhanced permeability and retention effect. Significantly enhanced chemo-photothermal combination therapy was also achieved due to excellent photothermal effect and near-infrared-light-triggered drug release by bGNR@MSN(DOX)-PEG at the tumor site. The promising results indicate great potential of bGNR@MSN-PEG nanoplatforms for future cancer diagnosis and therapy.


Assuntos
Ouro , Nanotubos , Dióxido de Silício , Animais , Antineoplásicos/administração & dosagem , Meios de Contraste/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Camundongos , Imagem Multimodal , Nanotubos/química , Neoplasias Experimentais/terapia , Técnicas Fotoacústicas/métodos , Fototerapia , Dióxido de Silício/química
13.
PLoS One ; 13(2): e0192890, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466447

RESUMO

BACKGROUND: Iron overload-related heart failure is the principal cause of death in transfusion dependent patients, including those with Thalassemia Major. Linking cardiac siderosis measured by T2* to therapy improves outcomes. T1 mapping can also measure iron; preliminary data suggests it may have higher sensitivity for iron, particularly for early overload (the conventional cut-point for no iron by T2* is 20ms, but this is believed insensitive). We compared T1 mapping to T2* in cardiac iron overload. METHODS: In a prospectively large single centre study of 138 Thalassemia Major patients and 32 healthy controls, we compared T1 mapping to dark blood and bright blood T2* acquired at 1.5T. Linear regression analysis was used to assess the association of T2* and T1. A "moving window" approach was taken to understand the strength of the association at different levels of iron overload. RESULTS: The relationship between T2* (here dark blood) and T1 is described by a log-log linear regression, which can be split in three different slopes: 1) T2* low, <20ms, r2 = 0.92; 2) T2* = 20-30ms, r2 = 0.48; 3) T2*>30ms, weak relationship. All subjects with T2*<20ms had low T1; among those with T2*>20ms, 38% had low T1 with most of the subjects in the T2* range 20-30ms having a low T1. CONCLUSIONS: In established cardiac iron overload, T1 and T2* are concordant. However, in the 20-30ms T2* range, T1 mapping appears to detect iron. These data support previous suggestions that T1 detects missed iron in 1 out of 3 subjects with normal T2*, and that T1 mapping is complementary to T2*. The clinical significance of a low T1 with normal T2* should be further investigated.


Assuntos
Sangue/diagnóstico por imagem , Técnicas de Imagem Cardíaca/métodos , Sobrecarga de Ferro/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Talassemia beta/diagnóstico por imagem , Adulto , Feminino , Humanos , Sobrecarga de Ferro/fisiopatologia , Modelos Lineares , Masculino , Estudos Prospectivos , Talassemia beta/fisiopatologia
14.
Mol Pharm ; 14(9): 3228-3237, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28726424

RESUMO

Herein we describe a formulation of self-encapsulating poly(lactic-co-glycolic acid) (PLGA) microspheres for vaccine delivery. Self-healing encapsulation is a novel encapsulation method developed by our group that enables the aqueous loading of large molecules into premade PLGA microspheres. Calcium phosphate (CaHPO4) adjuvant gel was incorporated into the microspheres as a protein-trapping agent for improved encapsulation of antigen. Microspheres were found to have a median size of 7.05 ± 0.31 µm, with a w/w loading of 0.60 ± 0.05% of ovalbumin (OVA) model antigen. The formulation demonstrated continuous release of OVA over a 49-day period. Released OVA maintained its antigenicity over the measured period of >21 days of release. C57BL/6 mice were immunized via the intranasal route with prime and booster doses of OVA (10 µg) loaded into microspheres or coadministered with cholera toxin B (CTB), the gold standard of mucosal adjuvants. Microspheres generated a Th2-type response in both serum and local mucosa, with IgG antibody responses approaching those generated by CTB. The results suggest that this formulation of self-encapsulating microspheres shows promise for further study as a vaccine delivery system.


Assuntos
Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Vacinas/administração & dosagem , Vacinas/química , Animais , Fosfatos de Cálcio/química , Toxina da Cólera/química , Cromatografia Líquida de Alta Pressão , Sistemas de Liberação de Medicamentos/métodos , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Ovalbumina/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
15.
Adv Healthc Mater ; 6(12)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28371568

RESUMO

Poly(lactic-co-glycolic acid) (PLGA) microspheres have been widely examined for vaccine applications due to their attractive features of biocompatibility, biodegradability, ability to be internalized by antigen-presenting cells, and long-term antigen release. However, one of the major challenges for PLGA particle vaccines is the potential for antigen instability and loss of antigenicity and immunogenicity. To address this challenge, we have developed a new method of "self-healing" encapsulation in PLGA microspheres, where pre-made PLGA microspheres are loaded with protein antigens under aqueous conditions with minimal impact on their antigenicity and immunogenicity. In this report, we show that mice immunized with self-encapsulating PLGA microspheres in a prime-boost regimen generated significantly enhanced antigen-specific CD8α+ T cell and antibody responses, compared with mice immunized with free, soluble protein admixed with calcium phosphate gel, a widely used adjuvant. Furthermore, a single-dose of microspheres designed for >40 day sustained antigen release elicited robust cellular and humoral immune responses as efficiently as the prime-boost vaccinations with calcium phosphate gel. Overall, these results suggest excellent potential of our self-encapsulating PLGA microspheres as a vaccine platform for multiple-dose as well as single-dose vaccinations.


Assuntos
Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Vacinação , Animais , Células Dendríticas/metabolismo , Relação Dose-Resposta Imunológica , Endocitose , Imunidade Celular , Imunidade Humoral , Camundongos Endogâmicos C57BL , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
16.
Clin Cancer Res ; 18(4): 1129-37, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22228638

RESUMO

PURPOSE: Signaling pathway stimulation by activating mutations of oncogenes occurs in most melanomas and can provide excellent targets for therapy, but the short-term therapeutic success is limited by intrinsic and acquired resistance. The mitogen-activated protein kinase and phosphoinositide 3-kinase/AKT/mTOR pathways are activated in most cutaneous melanomas. The purpose of this trial was to prospectively evaluate 2 molecularly targeted drug combinations in patients with untreated metastatic melanoma. EXPERIMENTAL DESIGN: This randomized phase II study enrolled patients between May 2008 and November 2009 with nonocular melanoma, no prior systemic chemotherapy, and no history of brain metastasis. Arm A received oral sorafenib 200 mg twice daily plus i.v. temsirolimus 25 mg weekly; and arm B received oral sorafenib 400 mg every morning, 200 mg every night daily plus oral tipifarnib 100 mg twice daily, 3 weeks of every 4. The primary objectives were to evaluate progression-free survival (PFS), objective response rate, and toxicity for the 2 regimens. RESULTS: On arm A (63 evaluable patients), the median PFS was 2.1 months and median overall survival (OS) was 7 months. Three patients achieved partial response (PR). Thirty-nine evaluable patients were accrued to arm B, which closed after first-stage accrual; the median PFS was 1.8 months and OS was 7 months, with 1 patient achieving PR. CONCLUSIONS: The combinations of molecularly targeted agents tested did not show sufficient activity to justify further use. Newer agents and improved patient selection by characterization of the molecular targets in individual tumors show great promise and should be incorporated into future studies, along with appropriate laboratory correlates.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Benzenossulfonatos/administração & dosagem , Feminino , Humanos , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Niacinamida/análogos & derivados , Compostos de Fenilureia , Piridinas/administração & dosagem , Quinolonas/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/análogos & derivados , Sorafenibe , Análise de Sobrevida , Resultado do Tratamento
17.
J Thorac Oncol ; 5(11): 1835-40, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20881645

RESUMO

INTRODUCTION: Sorafenib is a multikinase inhibitor affecting pathways involved in tumor progression and angiogenesis. We conducted a phase II trial of sorafenib in platinum-treated patients with extensive stage small cell lung cancer to determine the tumor response rate, toxicity, and overall survival. METHODS: Patients with histologically confirmed, measurable disease, Zubrod performance status 0 to 1, and no more than 1 prior platinum-based treatment were eligible. Patients were stratified by platinum-sensitivity status: sensitive (progression >90 days after platinum) or refractory (progression during or ≤90 days after platinum). Patients were treated with sorafenib 400 mg orally twice a day continuously on a 28-day cycle. RESULTS: Of 89 patients registered, 82 were evaluable for toxicity assessment, and 83 were evaluable for response. There were four partial responses seen among the 38 patients in the platinum-sensitive stratum, for an estimated response rate of 11% (95% confidence interval: 3-25%), and one partial response among the 45 patients in the platinum-refractory stratum, for an estimated response rate of 2% (95% confidence interval: 0-12%). The median overall survival estimates were 6.7 months (95% confidence interval: 6.1-9.1 months) for the platinum-sensitive stratum and 5.3 months (95% confidence interval: 3.3-7.5 months) in the platinum-refractory stratum. Nineteen patients discontinued treatment because of adverse events or side effects from therapy. CONCLUSIONS: Based on the lack of disease control seen in our trial, further investigation of single-agent sorafenib in the small cell lung cancer population is not recommended. Combination trials of sorafenib and chemotherapy are ongoing.


Assuntos
Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Recidiva Local de Neoplasia/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Piridinas/uso terapêutico , Terapia de Salvação , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Estadiamento de Neoplasias , Niacinamida/análogos & derivados , Compostos de Fenilureia , Indução de Remissão , Carcinoma de Pequenas Células do Pulmão/patologia , Sorafenibe , Taxa de Sobrevida , Resultado do Tratamento
18.
J Clin Oncol ; 28(20): 3330-5, 2010 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-20498388

RESUMO

PURPOSE: We conducted a phase II trial to evaluate the efficacy and safety of single-agent sorafenib in chemotherapy-naïve patients with metastatic or recurrent squamous cell carcinoma of the head and neck (SCCHN). The primary end point was response probability (ie, confirmed complete and partial response [PR]). PATIENTS AND METHODS: Chemotherapy-naïve patients with metastatic, persistent, or recurrent SCCHN who received one induction or fewer or received an adjuvant chemotherapy regimen, who had adequate organ function, and who had a performance status

Assuntos
Antineoplásicos/uso terapêutico , Benzenossulfonatos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Piridinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzenossulfonatos/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Avaliação de Medicamentos , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Niacinamida/análogos & derivados , Compostos de Fenilureia , Piridinas/efeitos adversos , Sorafenibe
19.
Head Neck ; 32(2): 221-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19557750

RESUMO

BACKGROUND: In an effort to optimize nonoperative therapy in patients with locoregionally advanced head and neck squamous cell cancer, the Southwest Oncology Group conducted a phase II trial combining 3-drug taxane-containing induction chemotherapy with accelerated fractionation/concomitant boost radiation and concomitant single-agent cisplatin. METHODS: Two induction courses using docetaxel (75 mg/m(2) on day 1), cisplatin (100 mg/m(2) on day 1), and fluorouracil (1000 mg/m(2)/day continuous intravenous infusion days 1-4) were given, with an interval of 21 days. Patients who were stable or responded to the chemotherapy received definitive accelerated fractionation/concomitant boost radiation with concurrent cisplatin (100 mg/m(2)) on days 1 and 22 of radiation. RESULTS: There were 74 eligible and evaluable patients enrolled between March 1, 2003, and August 15, 2004; 52 (70%) had stage IV disease. At least 1 grade 3-4 toxicity was experienced by 63 patients (85%) during induction. A total of 61 patients completed induction and began concurrent chemoradiotherapy; 50 (68%) completed all planned treatment. At least 1 grade 3-4 toxicity was noted in 53 of the 58 patients (91%) evaluated for toxicity from concurrent chemoradiotherapy. Two patients died during induction, and 2 during chemoradiation. With a median follow-up of 36 months (range, 14-50), the 2-year and 3-year overall survival estimates were 70% and 64%, with 2-year and 3-year progression-free survival estimates of 66% and 61%, respectively. CONCLUSIONS: Three-drug induction chemotherapy followed by accelerated fractionation/concomitant boost radiation and concurrent cisplatin is toxic but feasible within a cooperative group. In this patient cohort with advanced head and neck squamous cell cancer, overall and progression-free survivals were encouraging, justifying further study of this approach.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Cisplatino/uso terapêutico , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Docetaxel , Fracionamento da Dose de Radiação , Feminino , Fluoruracila/administração & dosagem , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante/métodos , Taxoides/administração & dosagem
20.
Int J Nanomedicine ; 3(3): 351-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18990944

RESUMO

Gold-coated silica nanoshells are a class of nanoparticles that can be designed to possess strong absorption of light in the near infrared (NIR) wavelength region. When injected intravenously, these nanoshells have been shown to accumulate in tumors and subsequently mediate photothermal treatment, leading to tumor regression. In this work, we sought to improve their specificity by targeting them to prostate tumor cells. We report selective targeting of PC-3 cells with nanoshells conjugated to ephrinA I, a ligand for EphA2 receptor that is overexpressed on PC-3 cells. We demonstrate selective photo-thermal destruction of these cells upon application of the NIR laser.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Nanoestruturas/uso terapêutico , Fototerapia/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Receptores da Família Eph , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Humanos , Raios Infravermelhos/uso terapêutico , Masculino
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