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1.
Orthop Nurs ; 42(1): 22-32, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36702093

RESUMO

Patients with total knee arthroplasty (TKA) experience pain, decreased muscle strength, and decreased knee function, resulting in increases in depression and decreased subjective well-being. A multidimensional home program may prevent these adverse events. The aim of this study was to test the effect of a home rehabilitation program that included education, exercise, aroma massage, and phone counseling for post-TKA patients. We used a randomized control group pretest/posttest design. Fifty-nine patients participated, with 29 in the experimental group and 30 in the control group. Pain, knee joint range of motion (ROM), quadriceps strength, depression, and subjective well-being were measured as outcome variables. Data were analyzed using repeated-measures analysis of variance and generalized estimating equations. The experimental group showed significant improvement in knee pain, active ROM, muscle strength, depression, and subjective well-being with no significant between-groups difference in passive ROM. The multidimensional home rehabilitation program can be an effective nursing intervention for physical and emotional recovery of patients with TKA.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Humanos , Idoso , Artroplastia do Joelho/reabilitação , Recuperação de Função Fisiológica , Articulação do Joelho/cirurgia , Terapia por Exercício/métodos , Osteoartrite do Joelho/cirurgia , Amplitude de Movimento Articular , Dor , Resultado do Tratamento
2.
EBioMedicine ; 58: 102926, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32739873

RESUMO

BACKGROUND: High recurrence and chemoresistance drive the high mortality in hepatocellular carcinoma (HCC). Although cancer stem cells are considered to be the source of recurrent and chemoresistant tumors, they remain poorly defined in HCC. Tonicity-responsive enhancer binding protein (TonEBP) is elevated in almost all HCC tumors and associated with recurrence and death. We aimed to identify function of TonEBP in stemness and chemoresistance of liver cancer. METHODS: Tumors obtained from 280 HCC patients were analyzed by immunohistochemical analyses. Stemness and chemoresistance of liver CSCs (LCSCs) were investigated using cell culture. Tumor-initiating activity was measured by implanting LCSCs into BALB/c nude mice. FINDINGS: Expression of TonEBP is higher in LCSCs in HCC cell lines and correlated with markers of LCSCs whose expression is significantly associated with poor prognosis of HCC patients. TonEBP mediates ATM-mediated activation of NF-κB, which stimulates the promoter of a key stem cell transcription factor SOX2. As expected, TonEBP is required for the tumorigenesis and self-renewal of LSCSs. Cisplatin induces the recruitment of the ERCC1/XPF dimer to the chromatin in a TonEBP-dependent manner leading to DNA repair and cisplatin resistance. The cisplatin-induced inflammation in LSCSs is also dependent on the TonEBP-ERCC1/XPF complex, and leads to enhanced stemness via the ATM-NF-κB-SOX2 pathway. In HCC patients, tumor expression of ERCC1/XPF predicts recurrence and death in a TonEBP-dependent manner. INTERPRETATION: TonEBP promotes stemness and cisplatin resistance of HCC via ATM-NF-κB. TonEBP is a key regulator of LCSCs and a promising therapeutic target for HCC and its recurrence.


Assuntos
Carcinoma Hepatocelular/patologia , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Endonucleases/metabolismo , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/patologia , Fatores de Transcrição/genética , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Chemistry ; 26(47): 10695-10701, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32428292

RESUMO

The development of photosensitizers for cancer photodynamic therapy has been challenging due to their low photostability and therapeutic inefficacy in hypoxic tumor microenvironments. To overcome these issues, we have developed a mitochondria-targeted photosensitizer consisting of an indocyanine moiety with triphenylphosphonium arms, which can self-assemble into spherical micelles directed to mitochondria. Self-assembly of the photosensitizer resulted in a higher photostability by preventing free rotation of the indoline ring of the indocyanine moiety. The mitochondria targeting capability of the photosensitizer allowed it to utilize intramitochondrial oxygen. We found that the mitochondria-targeted photosensitizer localized to mitochondria and induced apoptosis of cancer cells both normoxic and hypoxic conditions through generation of ROS. The micellar self-assemblies of the photosensitizer were further confirmed to selectively localize to tumor tissues in a xenograft tumor mouse model through passive targeting and showed efficient tumor growth inhibition.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Biophotonics ; 12(7): e201800481, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30729697

RESUMO

Recent progress in three-dimensional optical imaging techniques allows visualization of many comprehensive biological specimens. Optical clearing methods provide volumetric and quantitative information by overcoming the limited depth of light due to scattering. However, current imaging technologies mostly rely on the synthetic or genetic fluorescent labels, thus limits its application to whole-body visualization of generic mouse models. Here, we report a label-free optical projection tomography (LF-OPT) technique for quantitative whole mouse embryo imaging. LF-OPT is based on the attenuation contrast of light rather than fluorescence, and it utilizes projection imaging technique similar to computed tomography for visualizing the volumetric structure. We demonstrate this with a collection of mouse embryo morphologies in different stages using LF-OPT. Additionally, we extract quantitative organ information applicable toward high-throughput phenotype screening. Our results indicate that LF-OPT can provide multi-scale morphological information in various tissues including bone, which can be difficult in conventional optical imaging technique.


Assuntos
Embrião de Mamíferos/anatomia & histologia , Embrião de Mamíferos/diagnóstico por imagem , Imageamento Tridimensional/métodos , Tomografia Óptica/métodos , Animais , Camundongos
5.
Nat Commun ; 9(1): 4548, 2018 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-30382085

RESUMO

Targeted drug delivery using nanoparticles can minimize the side effects of conventional pharmaceutical agents and enhance their efficacy. However, translating nanoparticle-based agents into clinical applications still remains a challenge due to the difficulty in regulating interactions on the interfaces between nanoparticles and biological systems. Here, we present a targeting strategy for nanoparticles incorporated with a supramolecularly pre-coated recombinant fusion protein in which HER2-binding affibody combines with glutathione-S-transferase. Once thermodynamically stabilized in preferred orientations on the nanoparticles, the adsorbed fusion proteins as a corona minimize interactions with serum proteins to prevent the clearance of nanoparticles by macrophages, while ensuring systematic targeting functions in vitro and in vivo. This study provides insight into the use of the supramolecularly built protein corona shield as a targeting agent through regulating the interfaces between nanoparticles and biological systems.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Coroa de Proteína/química , Animais , Antineoplásicos/farmacologia , Proteínas Sanguíneas/química , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Ligação Proteica , Proteômica , Células RAW 264.7
6.
Biomacromolecules ; 19(7): 3030-3039, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29883544

RESUMO

Current drug delivery systems are hampered by poor delivery to tumors, in part reflecting poor encapsulation stability of nanocarriers. Although nanocarriers such as polymeric micelles have high colloidal stability and do not aggregate or precipitate in bulk solution, nanocarriers with low encapsulation stability can lose their cargo during circulation in blood due to interactions with blood cells, cellular membranes, serum proteins, and other biomacromolecules. The resulting premature drug release from carriers limits the therapeutic efficacy at target sites. Herein, we report a simple and robust technique to improve encapsulation stability of drug delivery systems. Specifically, we show that installation of disulfide cross-linked noncovalent polymer gatekeepers onto mesoporous silica nanoparticles with a high loading capacity for hydrophobic drugs enhances in vivo therapeutic efficacy by preventing premature release of cargo. Subsequent release of drug cargos was triggered by cleavage of disulfide cross-linking by glutathione, leading to improved antitumor activity of doxoroubicin in mice. These findings provide novel insights into the development of nanocarriers with high encapsulation stability and improved in vivo therapeutic efficacy.


Assuntos
Nanocápsulas/química , Animais , Antineoplásicos/administração & dosagem , Coloides/química , Reagentes de Ligações Cruzadas/química , Doxorrubicina/administração & dosagem , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Nus , Micelas , Nanocápsulas/efeitos adversos , Nanocápsulas/normas , Dióxido de Silício/química
7.
Oncotarget ; 7(43): 70898-70911, 2016 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-27765922

RESUMO

G-protein-coupled receptor 81 (GPR81) functions as a receptor for lactate and plays an important role in the regulation of anti-lipolytic effects in adipocytes. However, to data, a role for GPR81 in the tumor microenvironment has not been clearly defined. Here, GPR81 expression in breast cancer patients and several breast cancer cell lines was significantly increased compared with normal mammary tissues and cells. GPR81 knockdown resulted in impaired breast cancer growth and led to apoptosis both in vitro and in vivo. Furthermore, the inhibition of GPR81 signaling suppressed angiogenesis through a phosphoinositide 3-OH kinase (PI3K)/Akt-cAMP response element binding protein (CREB) pathway, which led to decreased production of the pro-angiogenic mediator amphiregulin (AREG). Overall, these findings identify GPR81 as a tumor-promoting receptor in breast cancer progression and suggest a novel mechanism that regulates GPR81-dependent activation of the PI3K/Akt signaling axis in tumor microenvironment.


Assuntos
Anfirregulina/metabolismo , Neoplasias da Mama/patologia , Neovascularização Patológica/patologia , Receptores Acoplados a Proteínas G/metabolismo , Microambiente Tumoral , Animais , Apoptose , Mama/irrigação sanguínea , Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Separação Celular/métodos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Ácido Láctico/metabolismo , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Biochem Cell Biol ; 93(3): 227-35, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25781488

RESUMO

Mast cells are responsible for IgE-mediated allergic responses through the secretion of various inflammatory cytokines and mediators. Therefore, the pharmacological regulation of mast cell activation is an important goal in the development of novel anti-allergic drugs. In this study, we found that spiraeoside (SP) inhibits mast cell activation and allergic responses in vivo. SP dose-dependently inhibited the degranulation induced by IgE-antigen (Ag) stimulation in RBL-2H3 mast cells without cytotoxic effects. At the molecular level, SP reduced the Ag-induced phosphorylation and subsequent activation of phospholipase C-γ2 (PLC-γ2). Moreover, SP inhibited the phosphorylation of spleen tyrosine kinase (Syk), linker for activation of T cells (LAT), and downstream MAPKs, such as ERK1/2, p38, and JNK, eventually attenuating expression of TNF-α and IL-4. Finally, we found that SP significantly inhibited IgE-mediated passive cutaneous anaphylaxis (PCA) in mice. Taken together, our results strongly suggest that SP suppresses IgE-mediated mast cell activation and allergic responses by inhibiting Lyn-induced PLC-γ2/MAPK signaling in mast cells.


Assuntos
Imunoglobulina E/imunologia , Mastócitos/efeitos dos fármacos , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Fosfolipase C gama/metabolismo , Quercetina/análogos & derivados , Animais , Linhagem Celular/efeitos dos fármacos , Citocinas/metabolismo , Imunoglobulina E/farmacologia , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Camundongos Endogâmicos BALB C , Anafilaxia Cutânea Passiva/imunologia , Fosforilação/efeitos dos fármacos , Quercetina/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo
9.
Sci Rep ; 4: 4805, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24925581

RESUMO

Adipose tissue functions as an endocrine organ, and the development of systemic inflammation in adipose tissue is closely associated with metabolic diseases, such as obesity and insulin resistance. Accordingly, the fine regulation of the inflammatory response caused by obesity has therapeutic potential for the treatment of metabolic syndrome. In this study, we analyzed the role of DJ-1 (PARK7) in adipogenesis and inflammation related to obesity in vitro and in vivo. Many intracellular functions of DJ-1, including oxidative stress regulation, are known. However, the possibility of DJ-1 involvement in metabolic disease is largely unknown. Our results suggest that DJ-1 deficiency results in reduced adipogenesis and the down-regulation of pro-inflammatory cytokines in vitro. Furthermore, DJ-1-deficient mice show a low-level inflammatory response in the high-fat diet-induced obesity model. These results indicate previously unknown functions of DJ-1 in metabolism and therefore suggest that precise regulation of DJ-1 in adipose tissue might have a therapeutic advantage for metabolic disease treatment.


Assuntos
Adipogenia/fisiologia , Tecido Adiposo/patologia , Modelos Animais de Doenças , Inflamação/etiologia , Obesidade/complicações , Proteínas Oncogênicas/fisiologia , Peroxirredoxinas/fisiologia , Células 3T3-L1 , Tecido Adiposo/metabolismo , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Técnicas Imunoenzimáticas , Inflamação/metabolismo , Inflamação/patologia , Resistência à Insulina , Camundongos , Camundongos Knockout , Obesidade/metabolismo , Obesidade/patologia , Proteína Desglicase DJ-1 , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
BMC Cancer ; 14: 431, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24927938

RESUMO

BACKGROUND: A common approach to cancer therapy in clinical practice is the combination of several drugs to boost the anticancer activity of available drugs while suppressing their unwanted side effects. In this regard, we examined the efficacy of combination treatment with the widely-used genotoxic drug doxorubicin and the mitochondriotoxic Hsp90 inhibitor gamitrinib to exploit disparate stress signaling pathways for cancer therapy. METHODS: The cytotoxicity of the drugs as single agents or in combination against several cancer cell types was analyzed by MTT assay and the synergism of the drug combination was evaluated by calculating the combination index. To understand the molecular mechanism of the drug synergism, stress signaling pathways were analyzed after drug combination. Two xenograft models with breast and prostate cancer cells were used to evaluate anticancer activity of the drug combination in vivo. Cardiotoxicity was assessed by tissue histology and serum creatine phosphokinase concentration. RESULTS: Gamitrinib sensitized various human cancer cells to doxorubicin treatment, and combination treatment with the two drugs synergistically increased apoptosis. The cytotoxicity of the drug combination involved activation and mitochondrial accumulation of the proapoptotic Bcl-2 family member Bim. Activation of Bim was associated with increased expression of the proapoptotic transcription factor C/EBP-homologous protein and enhanced activation of the stress kinase c-Jun N-terminal kinase. Combined drug treatment with doxorubicin and gamitrinib dramatically reduced in vivo tumor growth in prostate and breast xenograft models without increasing cardiotoxicity. CONCLUSIONS: The drug combination showed synergistic anticancer activities toward various cancer cells without aggravating the cardiotoxic side effects of doxorubicin, suggesting that the full therapeutic potential of doxorubicin can be unleashed through combination with gamitrinib.


Assuntos
Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/agonistas , Doxorrubicina/farmacologia , Proteínas de Membrana/agonistas , Proteínas Proto-Oncogênicas/agonistas , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Sinergismo Farmacológico , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas/metabolismo , Fator de Transcrição CHOP/agonistas , Fator de Transcrição CHOP/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Ther ; 21(5): 1004-13, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23511245

RESUMO

Periostin is an extracellular matrix (ECM) protein that is overexpressed in a variety of human cancers, and its functions appear to be linked to tumor growth, metastasis, and angiogenesis. Recent clinical evidence suggests that aberrant periostin expression is correlated with poor outcome in patients with breast cancer. To identify novel tools to regulate the functional role of periostin, we generated benzyl-d(U)TP-modified DNA aptamers that were directed against human periostin (PNDAs) and characterized their functional roles in breast cancer progression. PNDA-3 selectively bound to the FAS-1 domain of periostin with nanomolar affinity and disrupted the interaction between periostin and its cell surface receptors, αvß3 and αvß5 integrins. PNDA-3 markedly antagonized the periostin-induced adhesion, migration, and invasion of breast cancer cells and blocked the activation of various components of the αvß3 and αvß5 integrin signal transduction pathways. In a 4T1 orthotopic mouse model, PNDA-3 administration significantly reduced primary tumor growth and distant metastasis. Thus, our results demonstrated that periostin-integrin signaling regulates breast cancer progression at multiple levels in tumor cells and the tumor microenvironment. DNA aptamers targeting periostin may potentially be used to inhibit breast cancer progression.


Assuntos
Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Moléculas de Adesão Celular/metabolismo , Animais , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Neoplasias da Mama/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Feminino , Humanos , Integrinas/metabolismo , Camundongos , Dados de Sequência Molecular , Metástase Neoplásica , Ligação Proteica , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Nucl Med Biol ; 36(7): 711-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19720283

RESUMO

OBJECTIVES: We assessed the reproducibility of the kinetic analysis of 3'-deoxy-3'-[(18)F]fluorothymidine (FLT) positron emission tomography (PET) in A431 human epidermoid carcinoma and murine Lewis lung carcinoma (LLC) tumor models. METHODS: We injected 7.4 MBq of FLT (n=10 for each group) and acquired 2-h dynamic PET images. A second scan was performed 1 day later. We calculated standardized uptake value (SUV), kinetic rate constants, volume of distribution of phosphorylated FLT (V(dm)), net influx constant (K(FLT-CA)) and influx constant by Patlak graphical analysis (K(FLT-PA)). The percent difference between measurements of a parameter was calculated to compare the reproducibilities of different parameters. RESULTS: FLT phosphorylation was higher in mice with A431 tumors than in mice with LLC tumors (P<.005). Differences in the standard deviations of the percent differences of parameters were statistically significant (P<.001) in each model. In mice with A431 tumors, SUV, V(dm), K(FLT-CA) and K(FLT-PA) had standard deviations of the percent difference of < or = 20%. The most reproducible parameter was K(FLT-PA), although the standard deviation (15.6%) was not statistically different from those of V(dm) (15.8%), K(FLT-CA) (17.5%) and SUV (18.9%). In mice with LLC tumors, K(1), K(1)/k(2) and k(3) had standard deviations of the percent difference of < or = 20%. No macroparameters reflecting a total FLT flux had standard deviations of < or = 20%. CONCLUSION: Our results show the reproducibility of the kinetic macroparameters of FLT PET in mouse tumors with high FLT phosphorylation.


Assuntos
Carcinoma Pulmonar de Lewis/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Didesoxinucleosídeos , Tomografia por Emissão de Pósitrons/métodos , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Cinética , Masculino , Camundongos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
13.
J Nucl Med ; 49(12): 2057-66, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18997037

RESUMO

UNLABELLED: 3'-Deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) is a thymidine analog that was developed for measuring tumor proliferation with PET. The aim of this study was to establish a kinetic modeling analysis method for quantitative (18)F-FLT PET studies in subcutaneous tumor models in mice. METHODS: To explore the validity of an image-derived left ventricular input function, we measured equilibrium constants for plasma and whole blood and metabolite fractions in blood after (18)F-FLT injection. In parallel, dynamic (18)F-FLT PET scans were acquired in 24 mice with a small-animal dedicated PET scanner to compare arterial blood activities obtained by PET and blood sampling. We then investigated kinetic models for (18)F-FLT in human epithelial carcinoma (A431) and Lewis lung carcinoma tumor models in mice. Three-compartment models with reversible phosphorylation (k(4) not equal 0, 3C5P) and irreversible phosphorylation (k(4) = 0, 3C4P) and a 2-compartment model (2C3P) were examined. The Akaike information criterion and F statistics were used to select the best model for the dataset. Gjedde-Patlak graphic analysis was performed, and standardized uptake values in the last frame were calculated for comparison purposes. In addition, quantitative PET parameters were compared with Ki-67 immunostaining results. RESULTS: (18)F-FLT equilibrated rapidly (within 30 s) between plasma and whole blood, and metabolite fractions were negligible during PET scans. A high correlation between arterial blood sampling and PET data was observed. For 120-min dynamic PET data, the 3C5P model best described tissue time-activity curves for tumor regions. The net influx of (18)F-FLT (K(FLT)) and k(3) obtained with this model showed reasonable intersubject variability and discrimination ability for tumor models with different proliferation properties. The K(FLT) obtained from the 60- or 90-min data correlated well with that obtained from the 120-min data as well as with the Ki-67 results. CONCLUSION: The image-derived arterial input function was found to be feasible for kinetic modeling studies of (18)F-FLT PET in mice, and kinetic modeling analysis with an adequate compartment model provided reliable kinetic parameters for measuring tumor proliferation.


Assuntos
Didesoxinucleosídeos/farmacocinética , Modelos Biológicos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/metabolismo , Pele/diagnóstico por imagem , Pele/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Simulação por Computador , Interpretação de Imagem Assistida por Computador/métodos , Cinética , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética
14.
Pharm Res ; 24(4): 705-14, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17318418

RESUMO

PURPOSE: Anitangiogenic and apoptotic properties of a novel chemically modified heparin derivative with low anticoagulant activity were evaluated on the experimental in vitro and in vivo model. MATERIALS AND METHODS: Heparin-lithocholate conjugate (HL) was initially synthesized by covalently bonding lithocholate to heparin. Folate-HL conjugate (FHL) was further synthesized by conjugating folate to HL. Antiangiogenic and apoptotic abilities of HL and FHL were characterized in vitro and in vivo experimentations. RESULTS: Compared to unmodified heparin, both HL and FHL represented a low anticoagulant activity (38 and 28%, respectively). HL and FHL maintained antiangiogenic activity even further modification from the results of Matrigel plugs assay. FHL specifically induced apoptosis on KB cells having highly expressed folate receptor after cellular internalization. Both administered HL and FHL had similar antiangiogenic activity and inhibitory effect on tumor growth in vivo although FHL induced higher apoptosis on tumor tissues. CONCLUSIONS: In vivo tumor growth inhibition was possibly due to the decrease of vessel density and apoptotic cell death, although antiangiogenic effect of FHL seemed more actively affected on growth inhibition than apoptotic potential in vivo system. Thus, Low anticoagulant FHL having antiangiogenic and apoptotic properties would provide benefits for the development of a new class of anticancer agent.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Heparina/análogos & derivados , Ácido Litocólico/análogos & derivados , Neoplasias Experimentais/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/metabolismo , Inibidores da Angiogênese/uso terapêutico , Animais , Anticoagulantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colágeno , Modelos Animais de Doenças , Combinação de Medicamentos , Endocitose , Feminino , Receptores de Folato com Âncoras de GPI , Heparina/síntese química , Heparina/metabolismo , Heparina/farmacologia , Heparina/uso terapêutico , Humanos , Laminina , Ácido Litocólico/síntese química , Ácido Litocólico/metabolismo , Ácido Litocólico/farmacologia , Ácido Litocólico/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/patologia , Neoplasias Experimentais/fisiopatologia , Neovascularização Patológica/induzido quimicamente , Proteoglicanas , Receptores de Superfície Celular/metabolismo , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Biomaterials ; 28(6): 1236-47, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17126900

RESUMO

The development of more selective delivery systems for cancer diagnosis and chemotherapy is one of the most important goals of current anticancer research. The purpose of this study is to evaluate various self-assembled nanoparticles as candidates to shuttle radionuclide and/or drugs into tumors and to investigate the mechanisms underlying the tumor targeting with self-assembled nanoparticles. By combining different hydrophobic moieties and hydrophilic polymer backbones, various self-assembled nanoparticles were prepared, and their in vivo distributions in tumor-bearing mice were studied by radionuclide imaging. One type of nanoparticles (fluorescein isothiocyanate-conjugated glycol chitosan (FGC) nanoparticles) exhibited highly selective tumoral localization. Scintigraphic images obtained 1 day after the intravenous injection of FGC nanoparticles clearly delineated the tumor against adjacent tissues. The mechanisms underlying the tumor targeting with self-assembled nanoparticles were investigated in terms of the physicochemical properties of nanoparticles and tumor microenvironments. FGC nanoparticles were preferentially localized in perivascular regions, implying their extravasation to tumors through the hyperpermeable tumor vasculature. The magnitude and pattern of tumoral distribution of self-assembled nanoparticles were influenced by several key factors--(i) in vivo colloidal stability: nanoparticles should maintain their intact nanostructures in vivo for a long period of time, (ii) particle size, (iii) intracellular uptake of nanoparticle: fast cellular uptake greatly facilitates the tumor targeting, (iv) tumor angiogenesis: pathological angiogenesis permits access of nanoparticles to tumors. We believe that this work can provide insight for the engineering of nanoparticles and be extended to cancer therapy and diagnosis, so as to deliver multiple therapeutic agents and imaging probes at high local concentrations.


Assuntos
Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Animais , Cristalização/métodos , Portadores de Fármacos/química , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos , Tamanho da Partícula , Cintilografia , Distribuição Tecidual
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