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1.
Biochem Biophys Res Commun ; 514(4): 1278-1284, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31113615

RESUMO

Our previous study reported that cancer upregulated gene (CUG)2, a novel oncogene, induces both faster cell migration and anti-cancer drug resistance. We thus wonder whether CUG2 also induces stemness, a characteristic of cancer stem cells (CSCs) and further examine the molecular mechanism of this phenotype. To test that CUG2 induces stemness, we examined expression of stemness-related factors. Overexpression of CUG2 enhanced expression levels of stemness-related factors in human lung carcinoma A549 and immortalized bronchial BEAS-2B cells. Consequently, CUG2 increased cellular spherical cluster forming ability. Overexpression of CUG2 also induced tumor formation in xenotransplanted nude mice whereas transplantation of control cells failed to, implying that CUG2 possesses malignant tumorigenic potential. We paid attention to nucleophosmin (NPM1) for its known interaction with CUG2. Suppression of NPM1 hindered the CUG2-mediated stemness-like phenotypes and diminished TGF-ß transcriptional activity and signaling. TGF-ß increased stemness-like phenotypes in the control cells whereas TGF-ß inhibitor blocked induction of the phenotypes, indicating that NPM1 is required for CUG2-mediated stemness-like phenotypes through TGF-ß signaling. Furthermore, the suppression of Smad- and non-Smad-dependent TGF-ß signaling pathways also prevented CUG2 from inducing stemness-like phenotypes. Altogether, we suggest that the novel CUG2 oncogene promotes cellular transformation and stemness, mediated by nuclear NPM1 protein and TGF-ß signaling.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Células A549 , Animais , Células Cultivadas , Proteínas Cromossômicas não Histona/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nucleofosmina , Fenótipo
2.
Biochem Biophys Res Commun ; 484(2): 298-303, 2017 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-28126340

RESUMO

The cancer/testis (CT) antigen NY-SAR-35 gene is located on the X chromosome and is aberrantly expressed in various cancers but not in normal tissues, other than testes. Previously, we reported the expression of NY-SAR-35 enhanced cell growth, proliferation, and invasion in HEK293 and cancer cells. To extend understanding of the NY-SAR-35 gene, we used a next generation sequencing (NGS) approach. NY-SAR-35 expression induced growth, proliferation, metastasis, and stemness genes, as indicated by the up-regulations of CXCR4, EpCAM, CD133, and CD44, at the mRNA and protein levels. The expression of NY-SAR-35 in HEK293 cells significantly increased ERK phosphorylation, but not the phosphorylation of AKT. In HEK293/NY-SAR-35 cells, the expressions of pro-apoptotic proteins, including p53, Bax, and p21, were reduced and that of cyclin E was increased. Also, NY-SAR-35 increased the expressions of pluripotency genes (Nanog, Oct-4, and Sox2) and the ability of HEK293 cells to form colonies. Taken together, the present study indicates NY-SAR-35 functions as a CT antigen that triggers oncogenesis and self-renewal.


Assuntos
Antígeno AC133/metabolismo , Antígenos de Neoplasias/fisiologia , Molécula de Adesão da Célula Epitelial/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Receptores de Hialuronatos/metabolismo , Antígeno AC133/genética , Molécula de Adesão da Célula Epitelial/genética , Regulação da Expressão Gênica/fisiologia , Células HEK293 , Humanos , Receptores de Hialuronatos/genética , Regulação para Cima
3.
J Arthroplasty ; 32(3): 824-829, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27667531

RESUMO

BACKGROUND: Both rotating-platform (RP) mobile-bearing and medial-pivot (MP) fixed-bearing prostheses allow axial femorotibial rotation using a highly conforming polyethylene insert. However, limited comparative data are available between the 2 designs. This study was performed to compare the midterm clinical outcomes and patient-reported outcome measures (PROMs) of RP and MP prostheses. METHODS: We retrospectively reviewed the records of 52 total knee arthroplasties using RP mobile-bearing prosthesis and 49 total knee arthroplasties using MP fixed prosthesis with a minimum follow-up period of 5 years. Clinical and radiological outcomes, failure rates, and PROMs, including the Western Ontario and McMaster Universities Osteoarthritis Index score and satisfaction, were compared. RESULTS: There was no difference in clinical or radiographic outcomes (P > .1 for all comparisons), with the exception of the larger flexion contracture (FC) in the MP group (0.3° in RP vs 2.3° in MP, P < .01). No failure in either group was recorded during the study period. PROMs were comparable (P > .1 in all comparisons), with the exception of higher satisfactions in the RP group while performing light household duties (P < .01) and leisure or recreational activities (P = .014) in patients without FC. CONCLUSION: The midterm clinical results with both the RP mobile-bearing and MP fixed-bearing prostheses were satisfactory. Although both prostheses provided comparable PROMs, patients with an RP prosthesis were more satisfied than those with an MP prosthesis for highly demanding activities that are strongly associated with the presence of postoperative FC.


Assuntos
Artroplastia do Joelho/instrumentação , Prótese do Joelho , Medidas de Resultados Relatados pelo Paciente , Desenho de Prótese , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Polietileno , Radiografia , Amplitude de Movimento Articular , Estudos Retrospectivos
4.
Exp Cell Res ; 330(2): 451-459, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25218028

RESUMO

In the present study, we investigated whether celecoxib could induce the expression of NKG2D ligands in clonogenic colon cancer cells, and increase their susceptibility to NK cell-mediated cell death. Celecoxib and its non-coxib analog, 2,5-dimethyl celecoxib, induced ULBP-1 and DR5 in both COX-2 negative HCT-15 cells and COX-2 positive HT-29 cells. Celecoxib increased their susceptibility to NK92 cells in both DELFIA assay and soft agar colony forming assay. The inducibility of ULBP-1 and DR5 by celecoxib was not different between CD44- and CD44+ HCT-15 cells, and CD133- and CD133+ HT-29 cells. Celecoxib increased the susceptibility of highly clonogenic CD44+ HCT-15 and CD133+ HT-29 cells to NK92 cells, at least comparable to less clonogenic CD44- HCT-15 and CD133- HT-29 cells, respectively. In addition, celecoxib induced CHOP, and thapsigargin, an inducer of ER (endoplasmic reticulum) stress, induced DR5 but not ULBP1 in HCT-15. Taken together, these findings suggest that celecoxib induces the expression of ULBP-1 as well as DR5 in clonogenic colon cancer cells via COX-2 and ER stress-independent pathways, and increases their susceptibility to NK cells.


Assuntos
Neoplasias do Colo/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Células Matadoras Naturais/imunologia , Pirazóis/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Sulfonamidas/farmacologia , Antígeno AC133 , Antígenos CD/biossíntese , Celecoxib , Ciclo-Oxigenase 2/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas Ligadas por GPI/biossíntese , Glicoproteínas/biossíntese , Células HT29 , Humanos , Receptores de Hialuronatos/biossíntese , Peptídeos , Tapsigargina/farmacologia , Fator de Transcrição CHOP/biossíntese
5.
Immunol Invest ; 43(5): 447-62, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24654594

RESUMO

Various ex vivo or in vivo loading protocols have been developed or evaluated for the delivery of tumor antigens to dendritic cells (DCs). We compared the antitumor effect of mature DCs electroporation-pulsed (EP/mDC) ex vivo with tumor cell lysate and immature DCs (iDCs) injected into the tumor apoptosed by ionizing radiation (IR/iDC) in lung cancer model. DCs were generated from bone marrow of C57BL/6 mice. Ionizing radiation (IR) was applied at a dose of 10 Gy to the tumor on the right thigh. iDCs were intratumorally injected into the irradiated tumor and EP/mDC was injected subcutaneously in the right flank. DC injection induced strong tumor-specific immunity against Lewis lung carcinoma, as compared with the tumor-bearing control and IR only treated mice. The growth of a distant tumor on the right and left flank was inhibited by IR/iDC and EP/mDC. Particularly, IR/iDC resulted in a more significant inhibition of tumor growth and prolonged survival time. It was related to increase of tumor-specific interferon-gamma, cytotoxicity, and decrease of regulatory T-cells. The results indicate that DCs electroporation-pulsed with tumor cell lysate induce a potent antitumor effect, but that iDCs intratumoral injected into the irradiated tumor induce a more potent antitumor effect.


Assuntos
Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Neoplasias Pulmonares/imunologia , Animais , Vacinas Anticâncer/administração & dosagem , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Injeções Intralesionais , Injeções Subcutâneas , Interferon gama/biossíntese , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Camundongos , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
6.
Immunol Invest ; 42(4): 341-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23509890

RESUMO

Dendritic cells (DCs) are potent antigen-presenting cells that can be matured in vitro from immature dendritic cells (iDCs) in the presence of several biological agents such as cytokine cocktail, CD40L, TNF-a and antigen loading, which are necessary and achieved using various protocols, such as lipofection, passive pulse or electroporation. However, these DCs maturation protocols may cause with a significant loss of cells because of cellular attachment and spreading during culturing. Some biomaterials that influence adhesion and development of cells have been used in cell culture techniques, and it was thought that they might be applied on the culture of DCs. In this study, we used polyHEMA, which is a hydrogel coating biomaterial that prevents DCs from adherence, and investigated whether hydrogel coating affects the maturation of iDCs. The efficiency in the generation of mDCs was improved through hydrogel coating procedure and a dendritic cell maturation marker, CD83, was significantly increased in hydrogel-coated culture condition. The antigen-loaded mDCs from electroporation were further expressed the CD83. The mDCs generated in the hydrogel-coated culture condition showed more, longer and thicker dendrites, and produced more amounts of cytokines such as IL-12 and IFN-γ. Therefore, it was suggested that the hydrogel-coated culture condition could improve function of mDCs. Cheol-Hun Son and Jae-Ho Bae contributed equally to this work.


Assuntos
Células Dendríticas/citologia , Poli-Hidroxietil Metacrilato/farmacologia , Anticorpos/farmacologia , Antígenos/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Eletroporação , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Interferon gama/imunologia , Interleucina-12/imunologia , Células K562
7.
Sci Rep ; 13(1): 7656, 2023 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-37169953

RESUMO

Pancreatic cancer is difficult to diagnose at the initial stage and is often discovered after metastasis to nearby organs. Gemcitabine is currently used as a standard treatment for pancreatic cancer. However, since chemotherapy for pancreatic cancer has not yet reached satisfactory therapeutic results, adjuvant chemotherapy methods are attempted. It can be expected that combining immune cell therapy with existing anticancer drug combination treatment will prevent cancer recurrence and increase survival rates. We isolated natural killer (NK) cells and co-cultured them with strongly activated autologous peripheral blood mononuclear cells (PBMCs) as feeder cells, activated using CD3 antibody, IFN-r, IL-2, and γ-radiation. NK cells expanded in this method showed greater cytotoxicity than resting NK cells, when co-cultured with pancreatic cancer cell lines. Tumor growth was effectively inhibited in a pancreatic cancer mouse xenograft model. Therapeutic efficacy was increased by using gemcitabine and erlotinib in combination. These findings suggest that NK cells cultured by the method proposed here have excellent anti-tumor activity. We demonstrate that activated NK cells can efficiently inhibit pancreatic tumors when used in combination with gemcitabine-based therapy.


Assuntos
Gencitabina , Neoplasias Pancreáticas , Humanos , Animais , Camundongos , Leucócitos Mononucleares , Recidiva Local de Neoplasia/metabolismo , Células Matadoras Naturais , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/metabolismo , Imunoterapia/métodos , Linhagem Celular Tumoral , Neoplasias Pancreáticas
8.
Biochim Biophys Acta ; 1812(7): 796-805, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21514380

RESUMO

In this study, we investigated the role of c-Myc in overcoming multidrug resistance (MDR) in human ovarian and breast cancer cells by TRAIL. We showed that P-gp expressing MDR variants (Hey A8-MDR and MCF7-MDR cells) with high level of c-Myc were highly susceptible to TRAIL treatment when compared to their drug-sensitive parental human ovarian cancer Hey A8 and breast MCF-7 cells, respectively. Up-regulation of DR5 TRAIL receptor and down-regulation of c-FLIP and the promotion of caspase-dependent cell death, which contribute to TRAIL sensitization of MDR cells, were regulated by the over-expressed c-Myc in the MDR cells. After targeted inhibition of c-Myc with specific siRNA, these responses to TRAIL disappeared and TRAIL-induced apoptosis was also suppressed in MCF7-MDR cells. Treatment with TRAIL significantly reduced P-glycoprotein (P-gp)-mediated efflux of rhodamine123 in both Hey A8-MDR and MCF7-MDR cells. Furthermore, TRAIL significantly potentiated the cytotoxicity of vinblastine, vincristine, doxorubicin and VP-16 that are P-gp substrate anticancer drugs in both MDR cells, which resulted in the reversal effect of TRAIL on the MDR phenotype. The present study shows for the first time that elevated c-Myc expression in the MDR cells plays a critical role in overcoming MDR by TRAIL that can act as a specific sensitizer for P-gp substrate anticancer drug.


Assuntos
Neoplasias da Mama/patologia , Resistência a Múltiplos Medicamentos , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Sequência de Bases , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Primers do DNA , Feminino , Citometria de Fluxo , Humanos , Neoplasias Ovarianas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Cancer Sci ; 103(1): 7-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21951556

RESUMO

We have previously shown that inhibition of intracellular signaling pathways by treatment with quercetin induced the expression of natural killer cell group 2D (NKG2D) ligands on cancer cells and made the cells sensitive to natural killer (NK)-cell mediated cytotoxicity. In the present study, we investigated whether epidermal growth factor receptor (EGFR) inhibitors could induce the expression of NKG2D ligands in colon cancer cells. Treatment with EGFR inhibitors predominantly increased the levels of mRNA transcripts and surface protein of UL16-binding protein-1 (ULBP1) in various colon cancer cells, including KM12, Caco-2, HCT-15, and HT-29, which express EGFR, and increased susceptibility of these colon cancer cells to NK-92 cells. The expression of ULBP1 was not induced by inhibitors of nuclear factor-κB, phosphatidylinositol 3 kinase, and MAPK, but was induced by inhibitors of PKC, and the induction of ULBP1 expression with EGFR inhibitors was prevented by treatment with PMA in colon cancer cells. A transcription factor, activator protein-2 alpha (AP-2α), which has a suppressive effect on ULBP1 transcription, was prevented from binding to the ULBP1 promoter by treatment with EGFR inhibitors. The present study suggests that EGFR inhibitors can enhance the susceptibility to NK cell-mediated lysis of colon cancer cells by induction of ULBP1 via inhibition of the PKC pathway.


Assuntos
Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Citotoxicidade Imunológica/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Inibidores de Proteínas Quinases/farmacologia , Western Blotting , Imunoprecipitação da Cromatina , Neoplasias do Colo/tratamento farmacológico , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Citometria de Fluxo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Gefitinibe , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células Matadoras Naturais/metabolismo , Quinazolinas/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Regulação para Cima
10.
Mol Cancer ; 10: 46, 2011 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-21513580

RESUMO

BACKGROUND: Tumor recurrence and metastasis develop as a result of tumors' acquisition of anti-apoptotic mechanisms and therefore, it is necessary to develop novel effective therapeutics against metastatic cancers. In this study, we showed the differential TRAIL responsiveness of human prostate adenocarcinoma PC3 and human colon carcinoma KM12 cells and their respective highly metastatic PC3-MM2 and KM12L4A sublines and investigated the mechanism underlying high susceptibility of human metastatic cancer cells to TRAIL. RESULTS: PC3-MM2 and KM12L4A cells with high level of c-Myc and DNA-PKcs were more susceptible to TRAIL than their poorly metastatic primary PC3 and KM12 cells, which was associated with down-regulation of c-FLIPL/S and Mcl-1 and up-regulation of the TRAIL receptor DR5 but not DR4 in both metastatic cells. Moreover, high susceptibility of these metastatic cells to TRAIL was resulted from TRAIL-induced potent activation of caspase-8, -9, and -3 in comparison with their primary cells, which led to cleavage and down-regulation of DNA-PKcs. Knockdown of c-Myc gene in TRAIL-treated PC3-MM2 cells prevented the increase of DR5 cell surface expression, caspase activation and DNA-PKcs cleavage and attenuated the apoptotic effects of TRAIL. Moreover, the suppression of DNA-PKcs level with siRNA in the cells induced the up-regulation of DR5 and active caspase-8, -9, and -3. We also found that 4,5-dimethoxy-2-nitrobenzaldehyde (DMNB), a specific inhibitor of DNA-PK, potentiated TRAIL-induced cytotoxicity and apoptosis in relatively TRAIL-insensitive PC3 and KM12 cells and therefore functioned as a TRAIL sensitizer. CONCLUSION: This study showed the positive relationship between c-Myc expression in highly metastatic human prostate and colon cancer cells and susceptibility to TRAIL-induced apoptosis and therefore indicated that TRAIL might be used as an effective therapeutic modality for advanced metastatic cancers overexpressing c-Myc and combination of TRAIL therapy with agent that inhibits the DNA-PKcs/Akt signaling pathway might be clinically useful for the treatment of relatively TRAIL-insensitive human cancers.


Assuntos
Apoptose/efeitos dos fármacos , Benzaldeídos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Apoptose/genética , Western Blotting , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteína Quinase Ativada por DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Humanos , Masculino , Metástase Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ligante Indutor de Apoptose Relacionado a TNF/genética , Células Tumorais Cultivadas
11.
Chemistry ; 17(45): 12802-8, 2011 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21954062

RESUMO

Magnetic particles have become very promising materials for drug delivery. However, preparation of magnetite particles with high surface area, biocompatibility, strong magnetic response, and suitable particle size still remains a major challenge. In this report, magnetite nanocrystal clusters with high surface areas were fabricated through a solvothermal process by introducing ammonium acetate as a porogen and trisodium citrate as a surface modification agent. The porosity, which was controlled by the reactant concentration, has been investigated in detail. The surface area of the nanocrystal clusters was as high as 141 m(2) g(-1). Ibuprofen, as a model drug, was entrapped into the magnetite carriers. The interfacial interaction between the carboxylic groups on the drug molecules and the carboxylate groups on the carriers enhanced the loading efficiency. Low cytotoxicity in MCF-7 cell and in vitro constant drug release behavior combined with the high drug loading efficiency and high saturation magnetization values demonstrated the potential of the as-synthesized magnetite materials in targeted drug release systems.


Assuntos
Sistemas de Liberação de Medicamentos , Óxido Ferroso-Férrico/química , Ibuprofeno/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Feminino , Óxido Ferroso-Férrico/síntese química , Humanos , Porosidade , Solubilidade , Água
12.
Immunol Invest ; 40(4): 367-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21314289

RESUMO

Natural killer (NK) cells are important innate effector cells which can irradicate tumor cells through specific interactions between activating receptors on NK cells and their cognate ligands on cancer cells. Recently, it has been known that induction of activating NKG2D ligands including MHC class I chain-related (MIC) and UL16-binding protein (ULBP) families on tumor cells by various stresses makes them more susceptible to NK cell-mediated cytotoxicity. Therefore, it was investigated whether sublethal dose of hematoporphyrin-based photodynamic therapy (PDT) could up-regulate NKG2D ligands on tumor cells and increase the susceptibility of cancer cells against NK cells. Treatment with sublethal dose of hematoporphyrin-based PDT increased mRNA transcription and surface expression of ULBP1 and ULBP2 genes in SNU-1 human gastric tumor cell line and MICA/B, ULBP1, ULBP2 and ULBP3 genes in SW-900 human lung cancer cell line. These results were followed by increased susceptibility of cancer cells to NK cell-mediated cytotoxicity after sublethal PDT, which was abolished by addition of a blocking NKG2D mAb. Therefore, it could be suggested that the effect of hematoporphyrin-based PDT might be mediated in part by the increased susceptibility to NK cells via induction of NKG2D ligands on tumor cells, which survived after treatment with PDT.


Assuntos
Células Matadoras Naturais/imunologia , Ligantes , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Fotoquimioterapia , Regulação para Cima , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/imunologia , Carcinoma/tratamento farmacológico , Carcinoma/imunologia , Linhagem Celular Tumoral/imunologia , Linhagem Celular Tumoral/metabolismo , Citotoxicidade Imunológica , Regulação Neoplásica da Expressão Gênica , Hematoporfirinas/metabolismo , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/imunologia
13.
Immunol Invest ; 40(4): 383-99, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21314288

RESUMO

Growth of a tumor on the left flank was suppressed by direct injection of immature DCs (iDCs) into the irradiated tumor on the right thigh (IR/DC). This antitumor immune effect of IR/DC was enhanced by pretreatment with CTX (CTX+IR/DC) and this effect was related with increased number of tumor-specific IFN-γ secreting T cells and decreased ratio of CD4(+)CD25(+)/CD4(+) T cells. The treatment with CTX+IR/DC increased or decreased the levels of IL-2 or IL-10, respectively. These results demonstrated that antitumor effect of IR/DC could be augmented by pretreatment with low-dose CTX, suggesting a new antitumor therapeutic modality of chemoradioimmunotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Vacinas Anticâncer/administração & dosagem , Ciclofosfamida/administração & dosagem , Células Dendríticas/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Terapia Combinada , Feminino , Imunização , Interferon gama/biossíntese , Camundongos , Camundongos Endogâmicos C3H , Neoplasias/imunologia , Radioimunoterapia , Linfócitos T/imunologia , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Colloids Surf B Biointerfaces ; 208: 112119, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34571469

RESUMO

Tunable multi-responsive mesoporous silica nanoparticles were prepared by post-condensation/surface modification of MCM-41 nanoparticles. Surface grafting of a poly(N,N-dimethylaminoethyl methacrylate)-based polymer containing disulfide bonds was achieved by a click reaction. Chemical modification, morphological characteristics, and textural properties of the nanoparticles were studied using multiple characterization techniques such as Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy, small-angle X-ray scattering, and nitrogen adsorption/desorption behavior. The nanoparticles retained the meso-structural integrity of MCM41 and particle size < 100 nm after grafting with the polymer. The pH and redox-responsive behavior of the nanoparticles were also studied. The nanoparticles possess excellent drug-loading capacity owing to their large surface area and 'closed gate' mechanism of the grafted polymer chains. The release profile of doxorubicin at two different pH (7.4 and 5.5) and in the presence of dithiothreitol showed a dual response behavior. The nano drug carrier device exhibited efficient intracellular uptake in cancer cells with suitable cytotoxicity and pharmacokinetic behavior, and may therefore be considered a good candidate for cancer therapy.


Assuntos
Portadores de Fármacos , Nanopartículas , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Porosidade , Dióxido de Silício
15.
Mol Cancer ; 9: 199, 2010 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-20663232

RESUMO

BACKGROUND: The development of new modulator possessing high efficacy, low toxicity and high selectivity is a pivotal approach to overcome P-glycoprotein (P-gp) mediated multidrug resistance (MDR) in cancer treatment. In this study, we suggest a new molecular mechanism that TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) down-regulates P-glycoprotein (P-gp) through inhibition of DNA-PKcs/Akt/GSK-3beta pathway and activation of caspases and thereby sensitize MDR cells to MDR-related drugs. RESULTS: MDR variants, CEM/VLB10-2, CEM/VLB55-8 and CEM/VLB100 cells, with gradually increased levels of P-gp derived from human lymphoblastic leukemia CEM cells, were gradually more susceptible to TRAIL-induced apoptosis and cytotoxicity than parental CEM cells. The P-gp level of MDR variants was positively correlated with the levels of DNA-PKcs, pAkt, pGSK-3beta and c-Myc as well as DR5 and negatively correlated with the level of c-FLIPs. Hypersensitivity of CEM/VLB100 cells to TRAIL was accompanied by the activation of mitochondrial apoptotic pathway as well as the activation of initiator caspases. In addition, TRAIL-induced down-regulation of DNA-PKcs/Akt/GSK-3beta pathway and c-FLIP and up-regulation of cell surface expression of death receptors were associated with the increased susceptibility to TRAIL of MDR cells. Moreover, TRAIL inhibited P-gp efflux function via caspase-3-dependent degradation of P-gp as well as DNA-PKcs and subsequently sensitized MDR cells to MDR-related drugs such as vinblastine and doxorubicin. We also found that suppression of DNA-PKcs by siRNA enhanced the susceptibility of MDR cells to vincristine as well as TRAIL via down-regulation of c-FLIP and P-gp expression and up-regulation of DR5. CONCLUSION: This study showed for the first time that the MDR variant of CEM cells was hypersensitive to TRAIL due to up-regulation of DR5 and concomitant down-regulation of c-FLIP, and degradation of P-gp and DNA-PKcs by activation of caspase-3 might be important determinants of TRAIL-induced sensitization of MDR cells to MDR-related drugs. Therefore, combination of TRAIL and chemotherapeutic drugs may be a good strategy for treatment of cancer with multidrug resistance.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/farmacologia , Caspases/metabolismo , Regulação para Baixo , Ligante Indutor de Apoptose Relacionado a TNF/fisiologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Ativação Enzimática , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo
16.
Exp Cell Res ; 315(11): 1809-18, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19268463

RESUMO

TNF-related apoptosis-inducing ligand (TRAIL) is a pro-apoptotic cytokine that is capable of inducing apoptosis in a wide variety of cancer cells but not in normal cells. Although many cancer cells are sensitive to TRAIL-induced apoptosis, chronic myeloid leukemia (CML) develops resistance to TRAIL. In this study, we investigated whether apicidin, a novel histone deacetylase inhibitor, could overcome the TRAIL resistance in CML-derived K562 cells. Compared to treatment with apicidin or TRAIL alone, cotreatment with apicidin and TRAIL-induced apoptosis synergistically in K562 cells. This combination led to activation of caspase-8 and Bcl-2 interacting domain (Bid), resulting in the cytosolic accumulation of cytochrome c from mitochondria as well as an activation of caspase-3. Treatment with apicidin resulted in down-regulation of Bcr-Abl and inhibition of its downstream target, PI3K/AKT-NF-kappaB pathway. In addition, apicidin decreased the level of NF-kappaB-dependent Bcl-x(L), leading to caspase activation and Bid cleavage. These results suggest that apicidin may sensitize K562 cells to TRAIL-induced apoptosis through caspase-dependent mitochondrial pathway by regulating expression of Bcr-Abl and its related anti-apoptotic proteins. Therefore, the present study suggests that combination of apicidin and TRAIL may be an effective strategy for treating TRAIL-resistant Bcr-Abl expressing CML cells.


Assuntos
Proteínas de Fusão bcr-abl/metabolismo , Peptídeos Cíclicos/administração & dosagem , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Apoptose/efeitos dos fármacos , Sequência de Bases , Caspase 3/metabolismo , Caspase 8/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/administração & dosagem , Genes abl , Inibidores de Histona Desacetilases , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Interferente Pequeno/genética , Proteínas Recombinantes/administração & dosagem , Transdução de Sinais/efeitos dos fármacos
17.
J Pharm Pharmacol ; 61(8): 1043-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19703348

RESUMO

OBJECTIVES: The aim was to investigate the anti-inflammatory effects of Artemisia princeps extract on the activity of anti-CD3/CD28-stimulated CD4(+)CD25(-) T cells and antigen-expanded regulatory T cells. METHODS: CD4(+)CD25(-) T cells were activated with coated anti-CD3 and anti-CD28 and cultured in the presence or absence of various concentrations of A. princeps extract. The cultures were pulsed on Day 6 with [(3)H]thymidine and, after harvesting the cells, [(3)H]thymidine incorporation was measured. For analysis of interleukin-2 and interferon-gamma secreted from CD4(+)CD25(-) T cells, culture supernatants were collected on Days 2 and 6. For the analysis of interleukin-10 secreted from the CD4(+)CD25(-) T cells and expanded regulatory T cells, supernatants were collected after 2 and 7 days, respectively. Cytokine levels were determined using an enzyme-linked immunosorbent assay. Potential medicinal components of the A. princeps extract were determined using gas chromatography-mass spectrometry. KEY FINDINGS: A. princeps (30 microg/ml) effectively suppressed proliferation of CD4(+)CD25(-) T cells that were stimulated with anti-CD3/CD28 without causing cytotoxicity in spleen cells incubated under conditions lacking antigen stimulation. A. princeps inhibited production of the pro-inflammatory cytokines interleukin-2 and interferon-gamma in anti-CD3/CD28-stimulated CD4(+)CD25(-) T cells. Also, the extract slightly increased production of the anti-inflammatory cytokine interleukin-10 in these cells. In regulatory T cells expanded by anti-CD3/CD28, A. princeps increased production of interleukin-10 and Foxp3. CONCLUSIONS: The results suggest that A. princeps may be useful in the treatment of autoimmune diseases and organ transplantation rejection by inhibiting proliferation of inflammatory T cells, suppressing inflammatory processes in antigen-stimulated CD4(+)CD25(-) T cells and increasing activity of expanded regulatory T cells.


Assuntos
Anti-Inflamatórios/farmacologia , Artemisia/química , Extratos Vegetais/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Anti-Inflamatórios/isolamento & purificação , Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Cromatografia Gasosa-Espectrometria de Massas , Interferon gama/imunologia , Interleucina-2/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/imunologia
18.
Microbiol Res ; 163(2): 182-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-16782316

RESUMO

The dissimilatory perchlorate reducers mainly belong to two monophyletic groups, viz. Dechloromonas and Azospira in the beta subclass of Proteobacteria. The present study describes isolation and genetic characterization of Dechlorospirillum anomalous strain JB116 that belongs to alpha subclass of Proteobacteria. The strain JB116 was isolated under facultative anaerobic conditions on a growth medium containing sodium perchlorate and sodium acetate as electron (e(-)) acceptor and e(-) donor, respectively. The strain is a spirillum shaped, dissimilatory perchlorate and nitrate reducer that prefers nitrate to perchlorate. It grows heterotrophically with acetate at temperatures between 25-35 degrees C, NaCl concentrations between 0-0.5% and pH of 7-7.8. The strain JB116 is the second only representative strain within D. anomalous that shares 99% 16S rDNA sequence similarity with the type strain D. anomalous strain WD.


Assuntos
Proteobactérias/classificação , Proteobactérias/isolamento & purificação , Esgotos/microbiologia , Acetatos/metabolismo , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/isolamento & purificação , Sequência de Bases , Cloretos/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Nitratos/metabolismo , Percloratos/metabolismo , Filogenia , Proteobactérias/citologia , Proteobactérias/genética , RNA Ribossômico 16S/genética , Alinhamento de Sequência , Temperatura
19.
Cancer Lett ; 252(1): 75-85, 2007 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-17223257

RESUMO

In this study, we have tried to find new targets and effective drugs for imatinib-resistant chronic myelogenous leukemia (CML) cells displaying loss of Bcr-Abl kinase target dependence. The imatinib-resistant K562/R1, -R2 and -R3 cells showed profound declines of Bcr-Abl level and concurrently exhibited up-regulation of Bcl-2 and Ku70/80, and down-regulation of Bax, DNA-PKcs and BRCA1, suggesting that loss of Bcr-Abl after exposure to imatinib might be accompanied by other cell survival mechanism. K562/R3 cells were more sensitive to camptothecin (CPT)- and radiation-induced apoptosis than K562 cells, indicating hypersensitivity of imatinib-resistant cells to DNA damaging agents. Moreover, when K562 cells were treated with the combination of imatinib with CPT, the level of Bax and the cleavage of PARP-1 and DNA-PK were significantly increased in comparison with the effects of each drug. Therefore, our study suggests that CPT can be used to treat CML with loss of Bcr-Abl expression.


Assuntos
Antineoplásicos/farmacologia , Camptotecina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Piperazinas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Antígenos Nucleares/metabolismo , Proteína BRCA1/antagonistas & inibidores , Benzamidas , Linhagem Celular Tumoral , Enzimas Reparadoras do DNA/metabolismo , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteína Quinase Ativada por DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Sinergismo Farmacológico , Proteínas de Fusão bcr-abl , Humanos , Mesilato de Imatinib , Autoantígeno Ku , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Tolerância a Radiação , Proteína X Associada a bcl-2/antagonistas & inibidores , Proteína X Associada a bcl-2/metabolismo
20.
J Contam Hydrol ; 94(1-2): 76-85, 2007 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-17610987

RESUMO

Bioremediation by reductive dehalogenation of groundwater contaminated with tetrachloroethene (PCE) or trichloroethene (TCE) is generally carried out through the addition of a fermentable electron donor such as lactate, benzoate, carbohydrates or vegetable oil. These fermentable donors are converted by fermenting organisms into acetate and hydrogen, either of which might be used by dehalogenating microorganisms. Comparisons were made between H2 and acetate on the rate and extent of reductive dehalogenation of PCE. PCE dehalogenation with H2 alone was complete to ethene, but with acetate alone it generally proceeded only about half as fast and only to cis-1,2-dichloroethene (cDCE). Additionally, acetate was not used as an electron donor in the presence of H2. These findings suggest the fermentable electron donor requirement for PCE dehalogenation to ethene can be reduced up to 50% by separating PCE dehalogenation into two stages, the first of which uses acetate for the conversion of PCE to cDCE, and the second uses H2 for the conversion of cDCE to ethene. This can be implemented with a recycle system in which the fermentable substrate is added down-gradient, where the hydrogen being produced by fermentation effects cDCE conversion into ethene. The acetate produced is recycled up-gradient to achieve PCE conversion into cDCE. With the lower electron donor usage required, potential problems of aquifer clogging, excess methane production, and high groundwater chemical oxygen demand (COD) can be greatly reduced.


Assuntos
Acetatos/química , Hidrogênio/química , Tetracloroetileno/metabolismo , Tricloroetileno/metabolismo , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Abastecimento de Água , Anaerobiose , Biodegradação Ambiental , Elétrons , Fermentação , Halogenação , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Fatores de Tempo
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