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1.
Nucl Med Commun ; 45(4): 287-294, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38247556

RESUMO

OBJECTIVE: To investigate the impact of different tracer modifications on the imaging of cancer metabolism, focusing on the comparison of fluorescent glucose-analog tracers (2-NBDG and 2-DG-750) and the radiolabeled tracer 18F-FDG in both in-vitro and in-vivo settings. METHODS: We conducted an in-vitro comparative study using four cancer cell lines, each with unique glucose uptake characteristics. The study involved direct comparison of three tracers: 2-NBDG, 2-DG-750 and 18F-FDG, examining their internalization behaviors, metabolic functionality and localization effects in cancer metabolism imaging. RESULTS: The study revealed that each tracer exhibits distinct internalization behaviors correlated with imaging label size and type. 18F-FDG showed the highest uptake efficiency. Fluorescent molecules were found to accumulate in tumors primarily due to hydrophobic interactions and possible aggregation, indicating inefficiency in metabolism and suitability for imaging metabolic phenomena when compared to radiolabeled biomolecules. CONCLUSION: Our findings demonstrate that despite certain impracticalities, nuclear imaging, particularly using radiolabeled biomolecules like 18F-FDG, offers significant potential for accurately capturing biological phenomena. This is crucial for future advancements in both clinical and research settings. The study emphasizes the limitations of fluorescent molecules in imaging metabolic activities due to their inefficient metabolism and aggregation tendencies.


Assuntos
Fluordesoxiglucose F18 , Neoplasias , Humanos , Diagnóstico por Imagem , Radioisótopos , Neoplasias/diagnóstico por imagem , Glucose/metabolismo , Compostos Radiofarmacêuticos
2.
Mol Clin Oncol ; 18(5): 36, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37020506

RESUMO

Metaplastic breast carcinoma (MBC) is a heterogeneous group of invasive breast carcinomas (IBCs) characterized by the differentiation of the neoplastic epithelium toward squamous cells and/or mesenchymal-appearing elements. The present study describes the case of a 42-year-old woman who underwent a mastectomy and sentinel lymph node biopsy for two tumors in their left breast. One of the resected tumors was diagnosed as MBC with neuroendocrine (NE) differentiation and the other was diagnosed as IBC of no special type. The MBC tumor contained a matrix composed of basal lamina with a focal area of myxoid matrix and squamoid differentiation. To the best of our knowledge, the present study is the first report of MBC producing prominent basal lamina. The patient has remained alive and well for >10 years without recurrence, and has been treated with oral and injected anticancer drugs.

3.
In Vivo ; 35(6): 3125-3135, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34697143

RESUMO

BACKGROUND/AIM: Tumor cell destruction by boron neutron capture therapy (BNCT) is attributed to the nuclear reaction between 10B and thermal neutrons. The accumulation of 10B atoms in tumor cells without affecting adjacent healthy cells is crucial for effective BNCT. We previously reported that several types of liposomal boron delivery systems (BDS) delivered effective numbers of boron atoms to cancer tissues, and showed tumor-growth suppression after thermal neutron irradiation. In the present study, we examined the effects of BNCT after intra-arterial infusion of 10B-borono-dodecaborate (10BSH) by liposomal BDS in rabbit hepatic cancer models. MATERIALS AND METHODS: We prepared 10BSH-entrapped transferrin-conjugated polyethylene glycol liposomes constructed with distearoyl-boron lipid (TF-PEG-DSBL), and performed thermal neutron irradiation at the Kyoto University Institute for Integrated Radiation and Nuclear Science after intra-arterial infusion into rabbit VX-2 hepatic tumors. RESULTS: Concentrations of 10B in VX-2 tumors on delivery with TF-PEG-DSBL liposomes reached 25 ppm on day 3 after the injection. Tumor growth was suppressed by thermal neutron irradiation after intra-arterial injection of this 10BSH-containing liposomal BDS, without damage to normal cells. CONCLUSION: The present results demonstrate the applicability of 10B-containing TF-PEG-DSBL liposomes as a novel intra-arterial boron carrier in BNCT for cancer.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias Hepáticas , Animais , Boro , Lipossomos , Neoplasias Hepáticas/radioterapia , Coelhos
4.
In Vivo ; 35(1): 239-248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33402470

RESUMO

BACKGROUND/AIM: A mixture of anticancer agents and iodized poppy seed oil (IPSO) has been widely used for intra-arterial chemotherapy of hepatocellular carcinoma. However, the anticancer agents can easily separate from IPSO, so the therapeutic potential is limited. We developed epirubicin-entrapped water-in-oil-in-water emulsion (WOW-Epi) using a double-membrane emulsification technique. MATERIALS AND METHODS: We delivered WOW-Epi through a hepatic arterial injection to VX2 hepatic tumor rabbit model (1.2 mg/kg). RESULTS: VX2 tumor growth was selectively suppressed in the WOW-Epi-treated group compared with the control treated groups. The accumulation of WOW in nearby cancer cells was confirmed via electron-microscopy. Endocytosis seemed to be the mechanism underlying the uptake of WOW. CONCLUSION: WOW-Epi led to tumour growth suppression in vivo. WOW does not cause toxicity to arterial vessels. WOW-Epi will be hopefully used for repeated intra-arterial chemotherapy to HCC patients in the near future.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Emulsões , Epirubicina , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Coelhos , Água
5.
Gan To Kagaku Ryoho ; 37(11): 2052-7, 2010 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-21084802

RESUMO

The relationship has become clear between the expression of chemokine/chemokine receptors on cancer cells and the invasion, metastasis and peritoneal dissemination. Many cancer cells express chemokine receptors which are not expressed on the surface of normal tissues. Recently, it has been reported that overexpression of CXCR4/CXCL12 is related with metastasis to lung, liver, lymph nodes and bone marrow, while the overexpression of CCR7/CCL21 is mainly related with lymph node metastasis. We performed a comparative analysis of differential gene expressions related to chemokines/chemokine receptors, and cytokines in established gastric cancer cell lines by cDNA microarray. Upregulated chemokine genes were CCL21, CCL5, CXCL14, CCL2, CXCL1, CXCL8, CXCL7 and CXCL12, which the downregulated chemokines genes were MIP-1alpha and TECK. The upregulated gene of chemokine receptors was CCR-6. In the cancer microenvironment, cancer cells readily formed edematous and inflammatory conditions, easily metastasizing to other organs with the suppression of dendritic cells. The chemokines/chemokine receptors will hopefully become the new targets for cancer therapies for the regulation of metastasis.


Assuntos
Quimiocinas/fisiologia , Metástase Neoplásica/fisiopatologia , Receptores de Quimiocinas/fisiologia , Animais , Humanos
6.
Appl Radiat Isot ; 163: 109202, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32561043

RESUMO

We developed a mixing medical device by attaching Shirasu porous glass Millipore membrane to prepare water-in-oil-in-water (WOW) emulsion in a shorter time to be applied as 10B-entrapped WOW emulsion for hepatocellular carcinoma (HCC) treatment. Single-dose toxicity studies by intra-arterial injection of 10BSH-entrapped WOW were performed in rabbits and pig, and no side effects were observed. We hope to proceed to the preclinical and clinical studies for further evaluation of 10B compound as multidisciplinary treatments for HCC.


Assuntos
Compostos de Boro/toxicidade , Terapia por Captura de Nêutron de Boro/métodos , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Animais , Compostos de Boro/administração & dosagem , Emulsões , Injeções Intra-Arteriais , Óleos , Coelhos , Suínos , Água
7.
Expert Opin Drug Deliv ; 5(4): 427-43, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18426384

RESUMO

BACKGROUND: Tumor cell destruction in boron neutron capture therapy (BNCT) is due to the nuclear reaction between (10)B and thermal neutrons ((10)B + (1)n --> (7)Li + (4)He (alpha) + 2.31 MeV (93.7 %)/2.79 MeV (6.3 %)). The resulting lithium ions and alphaparticles are high linear energy transfer (LET) particles which give a high biological effect. Their short range in tissue (5 - 9 mum) restricts radiation damage to those cells in which boron atoms are located at the time of neutron irradiation. BNCT has been applied clinically for the treatment of malignant brain tumors, malignant melanoma, head and neck cancer and hepatoma. Sodium mercaptoundecahydro-dodecaborate (Na(2)(10)B(12)H(11)SH: BSH) and borono-phenylalanine ((10)BPA) are currently being used in clinical treatments. These low molecule compounds are easily cleared from cancer cells and blood, so high accumulation and selective delivery of boron compounds into tumor tissues and cancer cells are most important to achieve effective BNCT and to avoid damage to adjacent healthy cells. OBJECTIVE: In order to achieve the selective delivery of boron atoms to cancer cells, a drug delivery system (DDS) is an attractive intelligent technology for targeting and controlled release of drugs. METHODS: We performed literature searches related to boron delivery systems in vitro and in vivo. RESULTS: We describe several DDS technologies for boron delivery to cancer tissues and cancer cells from the past to current status. We are convinced that it will be possible to use liposomes, monoclonal antibodies and WOW emulsions as boron delivery systems for BNCT clinically in accordance with the preparation of good commercial product (GCP) grade materials.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Sistemas de Liberação de Medicamentos , Neoplasias/terapia , Animais , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Compostos de Boro/uso terapêutico , Preparações de Ação Retardada , Humanos
8.
Biomed Pharmacother ; 62(7): 448-53, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18255250

RESUMO

A new class of an anionic poly (ethylene glycol) derivative, PEG-Suc, bearing 17.7 pairs of carboxylic acid-side chains was synthesized. PEG-Suc deposited onto the DNA/polyethyleneimine complexes without destroying them even at high dose ratio. Coating of the DNA complexes by PEG-Suc recharged their surface to negative, and effectively protected them from the albumin-induced aggregation. Paired carboxyl groups in the side chains showed higher proton sponge effect. Negatively charged surface would diminish the electrostatic binding of the complexes to the cells, and the transfection efficiency on the cultured cells was not high. RGD peptide side chain as a ligand to malignant cell surfaces was then introduced to compensate the reduced electrical adhesion. RGD-PEG-Suc-coated plasmid/PEI complex brought about more than 3 times higher reporter protein activity on the cultured B16 cells. Those bio-compatible DNA complexes with ligand attained very high gene expression in tumor, lung, and liver after injection into mouse tail vein.


Assuntos
Ácidos Carboxílicos/química , Oligopeptídeos/química , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Ânions , DNA/biossíntese , DNA/genética , Eletroquímica , Terapia Genética/métodos , Proteínas de Fluorescência Verde/genética , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Microscopia de Fluorescência , Tamanho da Partícula , Plasmídeos , Potenciometria , Prótons , Transfecção
9.
Int J Pharm ; 346(1-2): 143-50, 2008 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-17640835

RESUMO

Oxaliplatin (trans-L-diaminocyclohexane oxalatoplatinum, L-OHP) is a novel cisplatin derivative that can improve the side effects of cisplatin such as toxicity to the kidneys and peripheral nerve system. However, L-OHP is effective only when combined with 5-Fluorouracil (5-FU) and Leucovorin. The relatively low anti-tumor index of L-OHP alone is because low levels accumulate in tumor tissues due to high partitioning to erythrocytes in vivo. A successful outcome of cancer therapy using L-OHP requires the selective delivery of a relatively high concentration of the drug to tumors. The present study examines tumor-selective delivery of L-OHP using liposomes modified with transferrin-conjugated polyethyleneglycol (TF-PEG-liposomes). Delivery using these liposomes significantly reduced L-OHP partitioning to erythrocytes and improved the circulation time of L-OHP in vivo, resulting in enhanced extravasation of liposomes into tumors. The TF-PEG-liposomes maintained a high L-OHP concentration in tumors for over 72 h after intravenous injection, which was longer than that of the liposomes modified with PEG (PEG-liposomes). Intravenously administered L-OHP encapsulated within TF-PEG-liposomes (L-OHP: 5 mg/kg) suppressed tumor growth more effectively than PEG-liposomes, Bare-liposomes and free L-OHP. Although L-OHP is usually combined with 5-FU and Leucovorin, our results suggest that L-OHP encapsulated within TF-PEG-liposomes has potential for cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Compostos Organoplatínicos/administração & dosagem , Polietilenoglicóis , Transferrina , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Eritrócitos/metabolismo , Rim/metabolismo , Lipossomos , Fígado/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Compostos Organoplatínicos/sangue , Compostos Organoplatínicos/farmacocinética , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Polietilenoglicóis/uso terapêutico , Baço/metabolismo , Distribuição Tecidual , Transferrina/química , Transferrina/farmacocinética , Transferrina/uso terapêutico
10.
Biomed Pharmacother ; 61(8): 505-14, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17614250

RESUMO

Pancreatic cancer is one of the most difficult neoplasms to cure and there is a need for new combinated therapy. If sufficient boron compound can be targeted accurate to the tumour, Boron Neutron-Capture Therapy (BNCT) can be applied to pancreatic cancer. We administrated BNCT to a cancer with pancreatic cancer patient using intraoperative irradiation. In this study, we performed preliminary dosimetry of a phantom model of the abdominal cavity. The flux of 8>x10(7)n/cm(2)/s (0.1 ratio) was 4.5 cm in depth from the surface in the case of simple irradiation, and the field of thermal neutrons was spread as 13 cm and 11.5 cm were usage of Void and Void with LiF collimation, respectively in thermal (OO-0011) mode. In the case of epithermal (CO-0000) mode, epithermal and fast components are four times higher at the surface level. In the case of mixed beam (OO-0000) mode, thermal neutron flux was the same as thermal neutron mode at a depth of 10 cm, but the gamma-ray component was two times higher than that of thermal neutron mode. With the use of Void and LiF collimation, thermal neutrons were selectively applied to the tumour combined with the CT-imaging of the cancer patient. This means that we could irradiate the tumour selectively and safely as possible, reducing the effects on neighboring healthy tissues. High resolution whole body dosimetry will be necessary to extend the application of BNCT to pancreatic cancer.


Assuntos
Terapia por Captura de Nêutron de Boro , Nêutrons , Neoplasias Pancreáticas/radioterapia , Imagens de Fantasmas , Abdome , Terapia por Captura de Nêutron de Boro/instrumentação , Humanos , Masculino , Neoplasias Pancreáticas/diagnóstico por imagem , Radiometria , Tomografia Computadorizada por Raios X
12.
J Control Release ; 254: 1-9, 2017 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-28336377

RESUMO

Boron neutron capture therapy is a promising tumor treatment method, though its wide application has been limited due to the poor tumor selectivity and intracellular delivery of 10B-compounds. Here, block copolymer-boron cluster conjugate based on the clinically used sodium borocaptate (BSH) and poly(ethylene glycol)-b-poly(glutamic acid) copolymer have been developed for effectively penetrating tumor tissues and homogeneously delivering the boron clusters into cancer cells towards safe and efficient boron neutron capture therapy. The PEGylated block copolymer-boron cluster (BSH) conjugate has demonstrated significant higher cellular uptake and tumor accumulation when compared to the non-PEGylated formulations and BSH. Moreover, the enhanced delivery to tumors of the conjugates, as well as their superior intratumoral penetration, which facilitated reaching the intracellular space of most cells in tumors, allowed the effective ablation of tumors after neutron irradiation.


Assuntos
Boroidretos/química , Terapia por Captura de Nêutron de Boro/métodos , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/radioterapia , Polietilenoglicóis/química , Ácido Poliglutâmico/química , Compostos de Sulfidrila/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Química Farmacêutica , Liberação Controlada de Fármacos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Permeabilidade
13.
Br J Radiol ; 90(1074): 20170004, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28406315

RESUMO

OBJECTIVE: Boron neutron-capture therapy (BNCT) has been used to inhibit the growth of various types of cancers. In this study, we developed a 10BSH-entrapped water-in-oil-in-water (WOW) emulsion, evaluated it as a selective boron carrier for the possible application of BNCT in hepatocellular carcinoma treatment. METHODS: We prepared the 10BSH-entrapped WOW emulsion using double emulsification technique and then evaluated the delivery efficacy by performing biodistribution experiment on VX-2 rabbit hepatic tumour model with comparison to iodized poppy-seed oil mix conventional emulsion. Neutron irradiation was carried out at Kyoto University Research Reactor with an average thermal neutron fluence of 5 × 1012 n cm-2. Morphological and pathological analyses were performed on Day 14 after neutron irradiation. RESULTS: Biodistribution results have revealed that 10B atoms delivery with WOW emulsion was superior compared with those using iodized poppy-seed oil conventional emulsion. There was no dissemination in abdomen or lung metastasis observed after neutron irradiation in the groups treated with 10BSH-entrapped WOW emulsion, whereas many tumour nodules were recognized in the liver, abdominal cavity, peritoneum and bilateral lobes of the lung in the non-injected group. CONCLUSION: Tumour growth suppression and cancer-cell-killing effect was observed from the morphological and pathological analyses of the 10BSH-entrapped WOW emulsion-injected group, indicating its feasibility to be applied as a novel intra-arterial boron carrier for BNCT. Advances in knowledge: The results of the current study have shown that entrapped 10BSH has the potential to increase the range of therapies available for hepatocellular carcinoma which is considered to be one of the most difficult tumours to cure.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Animais , Boro , Modelos Animais de Doenças , Emulsões , Papaver , Óleos de Plantas , Coelhos , Sementes , Distribuição Tecidual
14.
Mol Clin Oncol ; 5(6): 773-776, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28101355

RESUMO

Undifferentiated carcinoma of the gallbladder is a rare cancer type with a poor prognosis. The present study described a case of undifferentiated gallbladder carcinoma of the spindle- and giant-cell type, according to the 2010 World Health Organization classification. Hematoxylin and eosin staining revealed that the tumor consisted of dense interlacing bundles of spindle-shaped cells. No evidence of cartilaginous, osseous or rhabdomyosarcomatous differentiation was observed. Immunohistochemical staining revealed that spindle- and polygonal-shaped cells of the undifferentiated carcinoma were positive for cytokeratin AE1/3, vimentin and vascular endothelial growth factor. Furthermore, numerous spindle-shaped cells were positive for cluster of differentiation (CD)34 and CD31, and certain spindle-shaped cells were positive for Factor VIII. These results suggested classification of the present case as 'undifferentiated gallbladder carcinoma with endothelial differentiation'.

15.
J Cancer Res Clin Oncol ; 142(4): 767-75, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26650198

RESUMO

PURPOSE: A more immediate impact for therapeutic approaches of current clinical research efforts is of major interest, which might be obtained by developing a noninvasive radiation dose-escalation strategy, and neutron capture therapy represents one such novel approach. Furthermore, some recent researches on neutron capture therapy have focused on using gadolinium as an alternative or complementary for currently used boron, taking into account several advantages that gadolinium offers. Therefore, in this study, we carried out feasibility evaluation for both single and multiple injections of gadolinium-based MRI contrast agent incorporated in calcium phosphate nanoparticles as neutron capture therapy agent. METHODS: In vivo evaluation was performed on colon carcinoma Col-26 tumor-bearing mice irradiated at nuclear reactor facility of Kyoto University Research Reactor Institute with average neutron fluence of 1.8 × 10(12) n/cm(2). Antitumor effectivity was evaluated based on tumor growth suppression assessed until 27 days after neutron irradiation, followed by histopathological analysis on tumor slice. RESULTS: The experimental results showed that the tumor growth of irradiated mice injected beforehand with Gd-DTPA-incorporating calcium phosphate-based nanoparticles was suppressed up to four times higher compared to the non-treated group, supported by the results of histopathological analysis. CONCLUSION: The results of antitumor effectivity observed on tumor-bearing mice after neutron irradiation indicated possible effectivity of gadolinium-based neutron capture therapy treatment.


Assuntos
Fosfatos de Cálcio/administração & dosagem , Neoplasias do Colo/patologia , Neoplasias do Colo/radioterapia , Meios de Contraste/administração & dosagem , Gadolínio DTPA/administração & dosagem , Imageamento por Ressonância Magnética/métodos , Nanopartículas/administração & dosagem , Terapia por Captura de Nêutron/métodos , Animais , Estudos de Viabilidade , Feminino , Humanos , Injeções , Japão , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/radioterapia , Dosagem Radioterapêutica , Distribuição Tecidual , Resultado do Tratamento
16.
ACS Nano ; 9(6): 5913-21, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26033034

RESUMO

Gadolinium (Gd) chelates-loaded nanocarriers have high potential for achieving magnetic resonance imaging (MRI)-guided Gd neutron capture therapy (GdNCT) of tumors. Herein, we developed calcium phosphate micelles hybridized with PEG-polyanion block copolymers, and incorporated with the clinical MRI contrast agent Gd-diethylenetriaminepentaacetic acid (Gd-DTPA/CaP). The Gd-DTPA/CaP were nontoxic to cancer cells at the concentration of 100 µM based on Gd-DTPA, while over 50% of the cancer cells were killed by thermal neutron irradiation at this concentration. Moreover, the Gd-DTPA/CaP showed a dramatically increased accumulation of Gd-DTPA in tumors, leading to the selective contrast enhancement of tumor tissues for precise tumor location by MRI. The enhanced tumor-to-blood distribution ratio of Gd-DTPA/CaP resulted in the effective suppression of tumor growth without loss of body weight, indicating the potential of Gd-DTPA/CaP for safe cancer treatment.


Assuntos
Fosfatos de Cálcio/química , Meios de Contraste , Gadolínio DTPA , Imageamento por Ressonância Magnética/métodos , Micelas , Neoplasias/radioterapia , Terapia por Captura de Nêutron , Polímeros/química , Animais , Linhagem Celular Tumoral , Proliferação de Células , Quelantes , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Imagem Molecular , Neoplasias/diagnóstico
17.
Biomaterials ; 25(16): 3267-73, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14980421

RESUMO

Poly(ethylene glycol) (PEG) derivative having both carboxylic acid-, and lactose-side chains (Lac-PEG-C) deposited onto the surface of DNA/protamine (PRT) complex, and the self-assembled ternary complex was obtained. The diameter of the complexes was 180-200 nm, and they showed good size stability even in the high ionic strength solutions. Lac-PEG-C coating reduced their surface electric potential, and effectively avoided the albumin-induced aggregation. DNA/PRT/Lac-PEG-C complex did not coagulate the red blood cells, and their cytotoxicity evaluated by WST-1 was very low. Lac-PEG-C added to the plasmid/PRT complex prior to the incubation with HepG2 cells extremely enhanced the gene-expression, and by the plasmid/PRT/Lac-PEG-C complex prepared at 1:1.5:8 in weight, 56-fold higher expression of luciferase than that without Lac-PEG-C was observed. The treatment with asialofetuin or phenylarsine oxide evidently interfered with the gene-expression. The high gene expression by the plasmid/PRT/Lac-PEG-C ternary complex on the hepatocyte would be attributed to the asialoglycoprotein receptor-mediated endocytosis.


Assuntos
Carcinoma Hepatocelular/genética , Materiais Revestidos Biocompatíveis/química , Sistemas de Liberação de Medicamentos/métodos , Técnicas de Transferência de Genes , Lactose/química , Plasmídeos/administração & dosagem , Polietilenoglicóis/química , Protaminas/química , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Marcação de Genes/métodos , Terapia Genética/métodos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Teste de Materiais , Plasmídeos/química , Transfecção/métodos
18.
J Control Release ; 98(2): 195-207, 2004 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15262412

RESUMO

The successful treatment of cancer by boron neutron-capture therapy (BNCT) requires the selective delivery of relatively high concentration of 10B compounds to malignant tumor tissue. This study focuses on a new tumor-targeting drug delivery system for BNCT that uses small (less than 200 nm in diameter), unilamellar mercaptoundecahydrododecaborate (BSH)-encapsulating, transferrin (TF)-conjugated polyethyleneglycol liposomes (TF-PEG liposomes). When TF-PEG liposomes were injected at a dose of 35 mg 10B/kg, we observed a prolonged residence time in the circulation and low uptake by the reticuloendothelial system (RES) in Colon 26 tumor-bearing mice, resulting in enhanced accumulation of 10B into the solid tumor tissue (e.g., 35.5 microg/g). TF-PEG liposomes maintained a high 10B level in the tumor, with concentrations over 30 microg/g for at least 72 h after injection. This high retention of 10B in tumor tissue indicates that binding and concomitant cellular uptake of the extravasated TF-PEG liposomes occurs by TF receptor and receptor-mediated endocytosis, respectively. On the other hand, the plasma level of 10B decreased, resulting in a tumor/plasma ratio of 6.0 at 72 h after injection. Therefore, 72 h after injection of TF-PEG liposomes was selected as the time point of BNCT treatment. Administration of BSH encapsulated in TF-PEG liposomes at a dose of 5 or 20 mg 10B/kg and irradiation with 2 x 10(12) neutrons/cm2 for 37 min produced tumor growth suppression and improved long-term survival compared with PEG liposomes, bare liposomes and free BSH. Thus, intravenous injection of TF-PEG liposomes can increase the tumor retention of 10B atoms, which were introduced by receptor-mediated endocytosis of liposomes after binding, causing tumor growth suppression in vivo upon thermal neutron irradiation. These results suggest that BSH-encapsulating TF-PEG liposomes may be useful as a new intracellular targeting carrier in BNCT therapy for cancer.


Assuntos
Boroidretos/administração & dosagem , Terapia por Captura de Nêutron de Boro/métodos , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/radioterapia , Compostos de Sulfidrila/administração & dosagem , Animais , Área Sob a Curva , Boroidretos/farmacocinética , Boroidretos/uso terapêutico , Boro/análise , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Endocitose , Isótopos/análise , Lipossomos , Fígado/química , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/metabolismo , Neoplasias/mortalidade , Nêutrons , Tamanho da Partícula , Polietilenoglicóis/química , Compostos de Sulfidrila/farmacocinética , Compostos de Sulfidrila/uso terapêutico , Taxa de Sobrevida , Distribuição Tecidual , Transferrina/química , Transferrina/metabolismo
19.
Int J Pharm ; 237(1-2): 129-37, 2002 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11955811

RESUMO

We prepared tumor-specific immunoliposomes by coupling anti-BCG monoclonal antibodies to pH-sensitive fusogenic liposomes modified with succinylated polyglycidol (sucPG), in order to obtain efficient binding to, and endocytotic internalization into, the tumor cells. Mouse colon carcinoma 26 cells, which are known to share a common antigen with BCG, were used in in vitro experiments. BCG-sucPG immunoliposomes showed fusion ability under acidic conditions. Fluorescence microscopic observation indicated that BCG-sucPG immunoliposomes bound to colon 26 tumor cells and induced receptor-mediated endocytosis at 37 degrees C. Fusion assay by resonance energy transfer using N-(7-nitro-2-1,3-benzoxadiazol-4-yl) diacyl phosphatidylethanolamine and N-(lissamine rhodamine B sulfonyl) diacyl phosphatidylethanolamine suggested that fusion between BCG-sucPG immunoliposomes and endosomal and/or lysozomal membrane did occur. These results imply that the BCG-sucPG immunoliposomes transfer their content into the cytoplasm by fusing with the endosomal and/or lysozomal membrane after recognition of target cells and subsequent internalization into the cells by endocytosis.


Assuntos
Anticorpos Anti-Idiotípicos/administração & dosagem , Anticorpos Antibacterianos/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Líquido Intracelular/efeitos dos fármacos , Mycobacterium bovis/imunologia , Animais , Anticorpos Monoclonais/farmacocinética , Bovinos , Concentração de Íons de Hidrogênio , Imunotoxinas/administração & dosagem , Imunotoxinas/farmacocinética , Líquido Intracelular/metabolismo , Lipossomos , Camundongos , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/metabolismo
20.
Appl Radiat Isot ; 61(4): 573-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15246401

RESUMO

Statistical characteristics of photo-stimulated luminescent (PSL) signals are studied using thermal neutrons, X- and gamma-rays. It is shown that the statistical fluctuation of PSL is described simply by the PSL value itself and is independent of radiation type, except for short-range high-LET particles. However, it is expected that the spatial resolution should be affected if the range of electrons or secondaries were much longer than the instrumental resolution (pixel size). When output PSL signals are compared between X- and gamma-rays, the PSL values were proportional to the exposed air dose, independent of X-ray energy. However, signals from 60Co gamma-rays were approximately 1% of 22-40 kV X-ray output at the same dose.

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