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1.
Biomed Res Int ; 2019: 8530273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687402

RESUMO

In recent years, many studies have shown that recombinant adenovirus live vector-based vaccines are a promising novel vaccine candidate against virus infection. Therefore, in this study, a new type of recombinant adenovirus expressing the spike (S) protein of porcine epidemic diarrhea virus (PEDV), rAd-PEDV-S, was generated, and its characteristics were determined. Then, its efficacy as a vaccine candidate was evaluated in 4-week-old pigs. The results showed that the S protein could be well expressed at a high level in rAd-PEDV-S-infected cells and that the viral titers could reach 1011 PFU/mL. Further animal experimental results showed that rAd-PEDV-S elicited a significant PEDV-specific humoral immune response after vaccination (P < 0.05). In addition, rAd-PEDV-S provided partial protection for pigs against the highly virulent PEDV challenge. The results presented in this study indicate that the adenovirus vector can be used as a vaccine delivery vector for the development of a PEDV vaccine and is a promising novel vaccine candidate for future prevention and control of porcine epidemic diarrhea (PED), but its efficacy still needs to be improved in the future.

2.
Appl Microbiol Biotechnol ; 103(8): 3367-3379, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30888465

RESUMO

Many recent studies have shown that flagellin fused to heterologous antigens can induce significantly enhanced humoral and cellular immune responses through its adjuvant activity. Therefore, in this study, two key B cell epitopes and a truncated VP1 (ΔVP1) protein from foot-and-mouth disease virus (FMDV) were expressed as flagellin fusion proteins in different patterns. Specifically, ΔVP1 and two duplicates of two key B cell epitopes (2×B1B2) were fused separately to the C-terminus of flagellin with a universal exogenous T cell epitope to construct FT (Flagellin-Truncated VP1) and FME (Flagellin-Multiple Epitopes). In addition, the D3 domain of flagellin was replaced by ΔVP1 in FME, yielding FTME (Flagellin-Truncated VP1-Multiple Epitopes). The immunogenicity and protective efficacy of the three fusion proteins as novel FMDV vaccine candidates were evaluated. The results showed that FT, FME, and FTME elicited significant FMDV-specific IgG responses at 10 µg/dose compared with the mock group (P < 0.05), with FTME producing the highest response. No significant differences in the antibody response to FTME were observed between different immunization routes or among adjuvants (ISA-206, poly(I·C), MPLA, and CpG-ODN) in mice. In addition, at 30 µg/dose, all three fusion proteins significantly induced neutralizing antibody production and upregulated the levels of some cytokines, including TNF-α, IFN-γ, and IL-12, in guinea pigs. Importantly, all three fusion proteins provided effective protective immunity against FMDV challenge in guinea pigs, though different protection rates were found. The results presented in this study indicate that the FTME fusion protein is a promising novel vaccine candidate for the future prevention and control of foot-and-mouth disease.


Assuntos
Flagelina/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Vacinação/métodos , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Antígenos Virais/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Citocinas/sangue , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Flagelina/genética , Vírus da Febre Aftosa/genética , Cobaias , Masculino , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
3.
Vet Microbiol ; 230: 278-282, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30827401

RESUMO

Although highly virulent GII-genotype PEDV strains have become pandemic in the swine population worldwide, little is known about the differences in immunogenicity and cross-protective efficacy between the GIIa and GIIb subgenotypes. Hence, in the present study, we vaccinated suckling piglets with GIIa (CH/HBXT/2018) and GIIb (CH/HNPJ/2017) PEDV strain-based inactivated vaccine candidates and compared their immunogenicity and cross-protective efficacy. The results showed that both vaccine candidates induced high levels of PEDV-specific IgG antibodies and IFN-γ and reduced the levels of neutralizing antibodies at 21 dpv in suckling piglets. The GIIa-based inactivated vaccine protected all piglets (8/8) against virulent homologous and heterologous virus challenge, while the GIIb strain-based inactivated vaccine protected only 2/4 and 1/4 piglets against virulent homologous and heterologous virus challenge, respectively. Furthermore, antibodies against the GIIa and GIIb strains cross-reacted and cross-neutralized both strains in vitro. Taken together, the data presented in this study indicate that GIIa strain-based inactivated vaccine candidates are more promising than GIIb-based candidates for the development of an effective vaccine against the current highly virulent pandemic PEDV strains.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/veterinária , Proteção Cruzada/imunologia , Imunogenicidade da Vacina , Doenças dos Suínos/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Técnicas de Cultura de Células , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Genótipo , Imunoglobulina G/sangue , Interferon gama/imunologia , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/patogenicidade , Suínos , Doenças dos Suínos/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas Virais/administração & dosagem , Eliminação de Partículas Virais
4.
Arch Virol ; 164(5): 1287-1295, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859476

RESUMO

Since 2010, continual outbreaks of highly virulent variants of porcine epidemic diarrhea virus (PEDV) belonging to genotype GII have led to serious economic losses for the Chinese swine industry. To better understand the biological characteristics and pathogenicity of the current prevalent Chinese PEDV field strains, in this study, a highly virulent Chinese genotype GIIa PEDV strain, CH/HBXT/2018, was isolated and serially propagated using Vero cells. Sequencing and phylogenetic analysis showed that strain CH/HBXT/2018 contained novel insertion and deletion mutations in the S gene region relative to the classical strain and belonged to the genotype GIIa, similar to other recently isolated PEDV strains from China and the United States. Pig infection studies indicated that the CH/HBXT/2018 strain was highly virulent in suckling piglets, and the median pig diarrhea dose (PDD50) was 8.63 log10PDD50/3 mL at 7 days postinfection (DPI). The results of the present study are important for future PEDV challenge studies and the development of new PEDV vaccines based on prevalent field strains for the prevention and control of PED in China.


Assuntos
Infecções por Coronavirus/veterinária , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Animais , Linhagem Celular , China , Infecções por Coronavirus/virologia , Surtos de Doenças , Genótipo , Mutagênese Insercional/genética , Filogenia , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Deleção de Sequência/genética , Suínos , Doenças dos Suínos/virologia , Células Vero , Vacinas Virais/imunologia , Virulência/genética
5.
Virus Res ; 259: 18-27, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30342075

RESUMO

Since October 2010, severe porcine epidemic diarrhea (PED) outbreaks caused by highly virulent PED virus (PEDV) strains have occurred continuously in the Chinese pig population and caused considerable economic losses. Although PEDV vaccines based on classical PEDV strains have been widely used in China in recent years, the morbidity and mortality in piglets remain high. Therefore, virulent genotype GII PEDV strains that are prevalent in the field should be isolated and used to develop next-generation vaccines. In the present study, a Chinese virulent genotype GIIb PEDV strain, CH/HNPJ/2017, was serially propagated in Vero cells for up to 90 passages. The S genes contained typical insertions and deletions that were also found in other recently isolated highly virulent PEDV strains from China and other countries and had two neighboring unique insertion mutations, which resulted in four amino acid changes in the S1 region of passages P10 and P60. Pig infection studies revealed that the CH/HNPJ/2017 strain was highly virulent in piglets, and the median pig diarrhea dose (PDD50) was 7.68 log10PDD50/3 mL. Furthermore, the cell-adapted CH/HNPJ/2017 strain elicited potent serum IgG and neutralizing antibody responses in immunized pigs when it was used as an inactivated vaccine candidate. In addition, the pigs that received the experimental inactivated vaccines were partially protected (3/5) against subsequent viral challenge. In brief, these data indicate that the CH/HNPJ/2017 strain is a promising candidate for developing a safe and effective PEDV vaccine in the future.


Assuntos
Infecções por Coronavirus/veterinária , Genótipo , Vírus da Diarreia Epidêmica Suína/genética , Doenças dos Suínos/virologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Diarreia/veterinária , Interações Hospedeiro-Patógeno/imunologia , Testes de Neutralização , Filogenia , Vírus da Diarreia Epidêmica Suína/classificação , Vírus da Diarreia Epidêmica Suína/imunologia , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/patologia , Doenças dos Suínos/prevenção & controle , Vacinas de Produtos Inativados/imunologia , Células Vero , Vacinas Virais/imunologia , Virulência
6.
J Org Chem ; 83(15): 7860-7866, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29972639

RESUMO

We develop a palladium-catalyzed H/D exchange reaction with 8-aminoquinoline as the directing group as well as D2O as the source of deuterium atom and solvent. This reaction achieves selectively H/D exchange at the ortho-C-H of aromatic amides and the ß-C-H of aliphatic amide. Ortho-deuterated aromatic acids and ß-deuterated aliphatic acids are obtained by removal of the directing group. And a possible mechanism is also proposed.

7.
ACS Nano ; 8(12): 12450-60, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25375246

RESUMO

Plasmonic photothermal therapy utilizes biologically inert gold nanorods (AuNRs) as tumor-localized antennas that convert light into heat capable of eliminating cancerous tissue. This approach has lower morbidity than surgical resection and can potentially synergize with other treatment modalities including chemotherapy and immunotherapy. Despite these advantages, it is still challenging to obtain heating of the entire tumor mass while avoiding unnecessary collateral damage to surrounding healthy tissue. It is therefore critical to identify innovative methods to distribute an effective concentration of AuNRs throughout tumors without depositing them in surrounding healthy tissue. Here we demonstrate that AuNR-loaded, tumor-tropic neural stem cells (NSCs) can be used to improve the intratumoral distribution of AuNRs. A simple UV-vis technique for measuring AuNR loading within NSCs was established. It was then confirmed that NSC viability is unimpaired following AuNR loading and that NSCs retain AuNRs long enough to migrate throughout tumors. We then demonstrate that intratumoral injections of AuNR-loaded NSCs are more efficacious than free AuNR injections, as evidenced by reduced recurrence rates of triple-negative breast cancer (MDA-MB-231) xenografts following NIR exposure. Finally, we demonstrate that the distribution of AuNRs throughout the tumors is improved when transported by NSCs, likely resulting in the improved efficacy of AuNR-loaded NSCs as compared to free AuNRs. These findings highlight the advantage of combining cellular therapies and nanotechnology to generate more effective cancer treatments.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ouro/química , Ouro/uso terapêutico , Nanotubos , Células-Tronco Neurais/metabolismo , Fototerapia , Animais , Transporte Biológico , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Ouro/metabolismo , Humanos , Lasers , Camundongos
8.
Cell Biochem Biophys ; 70(1): 157-60, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24627141

RESUMO

This study explored the feasibility and clinical efficacy of expanded flap to repair facial scar left by radiotherapy of hemangioma. From March 2000 to April 2011, 13 cases of facial cicatrices left by radiotherapy of hemangioma have been treated with implantation surgery of facial skin dilator under local anesthesia. After water flood expansion for 1-2 months, resection of facial scar was performed, and wound repairing with expansion flap transfer was done. Thirteen patients were followed up from 5 months to 3 years. All patients tolerated flap transfer well; no contracture occurred during the facial expansion flap transfer. The incision scar was not obvious, and its color and texture were identical to surrounding skin. In conclusion, the use of expanded flap transfer to repair the facial scar left by radiotherapy of hemangioma is advantageous due to its simplicity, flexibility, and large area of repairing. This method does not affect the subsequent facial appearance.


Assuntos
Cicatriz/etiologia , Cicatriz/cirurgia , Hemangioma/radioterapia , Lesões por Radiação/cirurgia , Retalhos Cirúrgicos , Expansão de Tecido , Adolescente , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/etiologia , Adulto Jovem
9.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 29(2): 91-3, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23772483

RESUMO

OBJECTIVE: To investigate a new technique for nasal reconstruction with total rib cartilage framework. METHODS: The expanded frontal flap was fabricated by skin expansion and flap delay to cover the reconstructed nose. The dorsal flap was reversed as the lining of reconstructed nose. The whole framework was made by rib cartilage. Secondary revision operation was also performed to make the reconstructed nose more natural. RESULTS: Total nasal reconstruction was performed successfully in 37 cases. Each patient underwent 4-7 operation during a period of 6-8 months. 32 patients were followed up for 12-24 months. The reconstructed nose had a natural skin color and symmetric appearance with good ventilation and less scar. Both doctors and patients were satisfied with the results. CONCLUSION: Satisfactory cosmetic result and ventilation function can be achieved by nasal reconstruction with total rib cartilage framework.


Assuntos
Nariz/cirurgia , Rinoplastia/métodos , Costelas/transplante , Adulto , Braquetes , Feminino , Humanos , Masculino , Resultado do Tratamento
11.
PLoS One ; 8(1): e55220, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23372839

RESUMO

Western Bahr el Ghazal State is located in northwestern South Sudan, which is a tropical area subject to Plasmodium falciparum malaria epidemics. The aim of this study is to explore the epidemiological and clinical features of Plasmodium falciparum malaria in United Nations personnel stationed in this area. From July 2006 to June 2009, epidemiological data and medical records of 678 patients with Plasmodium falciparum malaria at the U.N. level 2 hospital were analyzed. The U.N. personnel were divided into individuals not immune to Plasmodium falciparum and individuals semi-immune to Plasmodium falciparum. The patients were divided into a chemoprophylaxis group (non-immune individuals who complied with the chemoprophylaxis regimen, 582 cases) and a no/incomplete chemoprophylaxis group (non-immune individuals who either did not fully comply with chemoprophylaxis or did not use it at all and semi-immune individuals who did not use chemoprophylaxis, 96 cases). Overall morbidity was about 11.3%. There was a significant difference in the morbidity of semi-immune and non-immune individuals (1.3% vs. 15.1%, P<0.001). Out of the total, 82.9% of cases occurred during the rainy season. The incidence of fever in the chemoprophylaxis group was significantly lower than in the no/incomplete chemoprophylaxis group (36.8% vs. 96.9%, P<0.001). Significant differences were observed between the two groups with respect to all other malaria-like symptoms except gastrointestinal symptoms, serum glucose level, platelet count, and alanine aminotransferase level. The incidence of complications was 1.2% (chemoprophylaxis group) and 44.8% (no/incomplete chemoprophylaxis group).The most common complication was thrombocytopenia, which was seen in 40.6% of the no/incomplete chemoprophylaxis group. In summary, Plasmodium falciparum malaria mainly occurred in rainy season. Gastrointestinal symptoms are an important precursor of malaria. Blood smears and rapid diagnostic tests should be performed after the onset of gastrointestinal symptoms. Appropriate chemoprophylaxis is necessary for reducing the severity of malaria.


Assuntos
Pessoal de Saúde , Malária Falciparum/diagnóstico , Malária Falciparum/epidemiologia , Nações Unidas , Adulto , Antimaláricos/uso terapêutico , Feminino , Humanos , Malária Falciparum/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prevalência , Resultado do Tratamento , Adulto Jovem
12.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 29(3): 167-9, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-25069339

RESUMO

OBJECTIVE: To investigate the correction of secondary nasal deformity of cleft lip with autogenous costal cartilage framework. METHODS: 237 cases with secondary nasal deformity of unilateral cleft lip were treated. The rib cartilage was harvested through a mini-invasive incision, and was fabricated as a C-shaped framework, as well as some cartilage fragments. Through transcolumella incision, the C-shaped framework was implanted to support the depressed alar and the cartilage fragments were used to augment the nasal base. RESULTS: Satisfactory cosmetic and functional results were achieved in all the patients with primary healing. 93 patients were followed up one year after operation with good cosmetic results. CONCLUSIONS: Autogenous costal cartilage framework can be used for the correction of secondary nasal deformity of cleft lip with satisfactory results.


Assuntos
Fenda Labial/cirurgia , Cartilagem Costal/transplante , Deformidades Adquiridas Nasais/cirurgia , Rinoplastia/métodos , Humanos
13.
Zhonghua Zheng Xing Wai Ke Za Zhi ; 28(2): 113-5, 2012 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-22737936

RESUMO

OBJECTIVE: To investigate the clinical effect of subcutaneous undermining dissection with continuous negative pressure drainage for the closure of cystic cavity-type bedsore. METHODS: 12 patients with cystic cavity-type bedsore underwent surgical debridement and the wounds were closed after subcutaneous undermining dissection. The negative pressure drainage was put in the deep space. The healing process was observed. RESULTS: Completed healing was achieved in all the 12 cases. The skin wounds healed after 17-20 days and the deep spaces closed after 36-43 days. 12 cases were followed up for 1 year with no occurrence. CONCLUSIONS: It is an easy and effective method to treat cystic cavity -type bedsore by subcutaneous undermining dissection with continuous negative pressure drainage.


Assuntos
Desbridamento/métodos , Drenagem/métodos , Tratamento de Ferimentos com Pressão Negativa , Lesão por Pressão/cirurgia , Cicatrização , Humanos
14.
Cell Biochem Biophys ; 64(2): 73-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22610701

RESUMO

The purpose of this study was to evaluate the refining plastic surgery techniques for repairing facial surface injury. For this purpose, 82 patients with facial surface injury were recruited in the study. All wounds were repaired by refining plastic surgery techniques. The wounds were processed by fine wound excision and plastic surgery repair technique. The deep tissue fracture and dislocation were sutured and reduced using 8-0 absorbable suture and the skin wounds were sutured using 8-0 cosmetic suture. The facial injuries showed good rates of healing with fine debridement and fine recovering. The minimum scarring was observed and good cosmetic effect was achieved. We conclude that refining plastic surgery techniques including fine debridement and fine recovering are ideal for the reconstruction of facial injuries.


Assuntos
Cicatriz/prevenção & controle , Traumatismos Faciais/cirurgia , Procedimentos Cirúrgicos Reconstrutivos/métodos , Lesões dos Tecidos Moles/cirurgia , Técnicas de Sutura/instrumentação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Desbridamento , Traumatismos Faciais/reabilitação , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Reconstrutivos/instrumentação , Lesões dos Tecidos Moles/reabilitação , Telas Cirúrgicas , Técnicas de Sutura/reabilitação , Suturas , Cicatrização
15.
Cell Biochem Biophys ; 62(2): 373-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22052001

RESUMO

The objective of this study was to evaluate the feasibility and clinical effect of repairing scalp defect after the excision of cutis verticis gyrata using expanded scalp skin flaps. For this purpose, 8 patients with cutis verticis gyrata were subjected to scalp skin expander implantation under the skin. After saline injection and scalp expansion for 2-3 months, the cutis verticis gyrata was excised and the expanded scalp flaps were applied to recover the skin defect. As a result, the flaps and hair grew well without contractures and significant scarring, suggesting that this method is useful for surgical correction of cutis verticis gyrata.


Assuntos
Dermatoses do Couro Cabeludo/terapia , Expansão de Tecido , Adolescente , Adulto , Feminino , Humanos , Lidocaína/administração & dosagem , Masculino , Pessoa de Meia-Idade , Couro Cabeludo/anormalidades , Dermatoses do Couro Cabeludo/cirurgia , Adulto Jovem
16.
Stem Cells ; 30(2): 314-25, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22084033

RESUMO

Metastasis to multiple organs is the primary cause of mortality in breast cancer patients. The poor prognosis for patients with metastatic breast cancer and toxic side effects of currently available treatments necessitate the development of effective tumor-selective therapies. Neural stem cells (NSCs) possess inherent tumor tropic properties that enable them to overcome many obstacles of drug delivery that limit effective chemotherapy strategies for breast cancer. We report that increased NSC tropism to breast tumor cell lines is strongly correlated with the invasiveness of cancer cells. Interleukin 6 (IL-6) was identified as a major cytokine mediating NSC tropism to invasive breast cancer cells. We show for the first time in a preclinical mouse model of metastatic human breast cancer that NSCs preferentially target tumor metastases in multiple organs, including liver, lung, lymph nodes, and femur, versus the primary intramammary fat pad tumor. For proof-of-concept of stem cell-mediated breast cancer therapy, NSCs were genetically modified to secrete rabbit carboxylesterase (rCE), an enzyme that activates the CPT-11 prodrug to SN-38, a potent topoisomerase I inhibitor, to effect tumor-localized chemotherapy. In vitro data demonstrate that exposure of breast cancer cells to conditioned media from rCE-secreting NSCs (NSC.rCE) increased their sensitivity to CPT-11 by 200-fold. In vivo, treatment of tumor-bearing mice with NSC.rCE cells in combination with CPT-11 resulted in reduction of metastatic tumor burden in lung and lymph nodes. These data suggest that NSC-mediated enzyme/prodrug therapy may be more effective and less toxic than currently available chemotherapy strategies for breast cancer metastases.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/patologia , Células-Tronco Neurais/transplante , Pró-Fármacos/uso terapêutico , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Biotransformação , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Camptotecina/uso terapêutico , Carboxilesterase/biossíntese , Carboxilesterase/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Irinotecano , Neoplasias Pulmonares/tratamento farmacológico , Metástase Linfática , Neoplasias Mamárias Experimentais/tratamento farmacológico , Camundongos , Camundongos Nus , Invasividade Neoplásica , Células-Tronco Neurais/enzimologia , Células-Tronco Neurais/metabolismo , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacocinética , Coelhos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Mol Cancer Res ; 6(12): 1819-29, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19074827

RESUMO

Hypoxia is a critical aspect of the microenvironment in glioma and generally signifies unfavorable clinical outcome. Effective targeting of hypoxic areas in gliomas remains a significant therapeutic challenge. New therapeutic platforms using neural stem cells (NSC) for tumor-targeted drug delivery show promise in treatment of cancers that are refractory to traditional therapies. However, the molecular mechanisms of NSC targeting to hypoxic tumor areas are not well understood. Therefore, we investigated the role of hypoxia in directed migration of NSCs to glioma and identified the specific signaling molecules involved. Our data showed that hypoxia caused increased migration of human HB1.F3 NSCs to U251 human glioma-conditioned medium in vitro. In HB1.F3 NSCs, hypoxia led to up-regulation of CXCR4, urokinase-type plasminogen activator receptor (uPAR), vascular endothelial growth factor receptor 2 (VEGFR2), and c-Met receptors. Function-inhibiting antibodies to these receptors inhibited the migration of HB1.F3 cells to glioma-conditioned medium. Small interfering RNA knockdown of hypoxia-inducible factor-1alpha in glioma cells blocked the hypoxia-induced migration of NSCs, which was due to decreased expression of stromal cell-derived factor-1 (SDF-1), uPA, and VEGF in glioma cells. Our in vivo data provided direct evidence that NSCs preferentially distributed to hypoxic areas inside intracranial glioma xenografts, as detected by pimonidazole hypoxia probe, as well as to the tumor edge, and that both areas displayed high SDF-1 expression. These observations indicate that hypoxia is a key factor in determining NSC tropism to glioma and that SDF-1/CXCR4, uPA/uPAR, VEGF/VEGFR2, and hepatocyte growth factor/c-Met signaling pathways mediate increased NSC-to-glioma tropism under hypoxia. These results have significant implications for development of stem cell-mediated tumor-selective gene therapies.


Assuntos
Neoplasias Encefálicas/terapia , Movimento Celular/fisiologia , Glioma/terapia , Hipóxia/patologia , Células-Tronco/citologia , Animais , Especificidade de Anticorpos , Neoplasias Encefálicas/patologia , Linhagem Celular Transformada , Meios de Cultivo Condicionados , Citocinas/genética , Citocinas/imunologia , Sistemas de Liberação de Medicamentos/métodos , Feminino , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Glioma/patologia , Humanos , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Camundongos Nus , Testes de Neutralização , RNA Interferente Pequeno , Transplante de Células-Tronco , Células-Tronco/imunologia , Telencéfalo/citologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Stem Cells ; 26(6): 1406-13, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18403751

RESUMO

Human neural and mesenchymal stem cells have been identified for cell-based therapies in regenerative medicine and as vehicles for delivering therapeutic agents to areas of injury and tumors. However, the signals required for homing and recruitment of stem cells to these sites are not well understood. Urokinase plasminogen activator (uPA) and urokinase plasminogen activator receptor (uPAR) are involved in chemotaxis and cell guidance during normal development and are upregulated in invasive tumors. Here we provided evidence that activation of uPA and uPAR in malignant solid tumors (brain, lung, prostate, and breast) augments neural and mesenchymal stem cell tropism. Expression levels of uPAR on human solid tumor cell lines correlated with levels of uPA and soluble uPAR in tumor cell-conditioned media. Cytokine expression profiles of these tumor-conditioned media were determined by protein arrays. Among 79 cytokines investigated, interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 were the most highly expressed cytokines in uPAR-positive tumors. We provided evidence that human recombinant uPA induced stem cell migration, whereas depletion of uPA from PC-3 prostate cancer cell-conditioned medium blocked stem cell migration. Furthermore, retrovirus-mediated overexpression of uPA and uPAR in neuroblastoma (NB1691) cells induced robust migration of stem cells toward NB1691 cell-conditioned media, compared with media derived from wild-type NB1691 cells. We conclude that expression of uPA and uPAR in cancer cells underlies a novel mechanism of stem cell tropism to malignant solid tumors, which may be important for development of optimal stem cell-based therapies. Disclosure of potential conflicts of interest is found at the end of this article.


Assuntos
Células-Tronco Mesenquimais/fisiologia , Neoplasias/fisiopatologia , Receptores de Superfície Celular/fisiologia , Células-Tronco/fisiologia , Ativador de Plasminogênio Tipo Uroquinase/fisiologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/fisiopatologia , Masculino , Mesencéfalo/embriologia , Mesencéfalo/fisiopatologia , Células-Tronco Mesenquimais/citologia , Neuroblastoma , Reação em Cadeia da Polimerase , Neoplasias da Próstata/fisiopatologia , Receptores de Superfície Celular/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Células-Tronco/citologia , Ativador de Plasminogênio Tipo Uroquinase/genética
19.
FEBS Lett ; 580(15): 3624-30, 2006 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-16753148

RESUMO

Ultraviolet (UV) irradiation can result in cell cycle arrest. The reactivation of Polo-like kinase 1 (Plk1) is necessary for cell cycle reentry. But the mechanism of how Plk1 regulates p53 in UV-induced mitotic arrest cells remained elusive. Here we find that UV treatment leads HEK293 cells to inverse changes of Plk1 and p53. Over-expression of Plk1 rescue UV-induced mitotic arrest cells by inhibiting p53 activation. Plk1 could also inhibit p53 phosphorylation at Ser15, thus facilitates its nuclear export and degradation. Further examination shows that Plk1, p53 and Cdc25C can form a large complex. Plk1 could bind to the sequence-specific DNA-binding domain of p53 and active Cdc25C by hyperphosphorylation. These results hypothesize that Plk1 and Cdc25C participate in recovery the mitotic arrest through binding to the different domain of p53. Cdc25C may first be actived by Plk1, and then its phosphatase activity makes p53 dephosphorylated at Ser15.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Mitose/efeitos da radiação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular , Dano ao DNA/genética , Humanos , Fosforilação/efeitos da radiação , Fosfosserina/metabolismo , Ligação Proteica , Processamento de Proteína Pós-Traducional , Transporte Proteico , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Fosfatases cdc25/metabolismo
20.
Mol Cancer Ther ; 4(10): 1577-84, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16227408

RESUMO

c-Met is highly expressed and constitutively activated in various human tumors. We employed adenovirus-mediated RNA interference technique to knock down c-Met expression in hepatocellular carcinoma cells and observed its effects on hepatocellular carcinoma cell growth in vitro and in vivo. Among the five hepatocellular carcinoma and one normal human liver cell lines we analyzed, c-Met was highly expressed and constitutively tyrosine phosphorylated in only MHCC97-L and HCCLM3 hepatocellular carcinoma cells. Knockdown of c-Met could inhibit MHCC97-L cells proliferation by arresting cells at G0-G1 phase. Soft agar colony formation assay indicated that the colony forming ability of MHCC97-L cells decreased by approximately 70% after adenovirus AdH1-small interfering RNA (siRNA)/met infection. In vivo experiments showed that adenovirus AdH1-siRNA/met inhibited the tumorigenicity of MHCC97-L cells and significantly suppressed tumor growth when injected directly into tumors. These results suggest that knockdown of c-Met by adenovirus-delivered siRNA may be a potential therapeutic strategy for treatment of hepatocellular carcinoma in which c-Met is overexpressed.


Assuntos
Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , RNA Interferente Pequeno/genética , Adenoviridae/genética , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Proteínas Proto-Oncogênicas c-met/biossíntese , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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