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1.
Res Involv Engagem ; 7(1): 46, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174961

RESUMO

BACKGROUND: Public involvement in clinical translational research is increasingly recognised as essential for relevant and reliable research. Public involvement must be diverse and inclusive to enable research that has the potential to reach those that stand to benefit from it the most, and thus address issues of health equity. Several recent reports, however, indicate that public involvement is exclusive, including in its interactions with ethnic groups. This paper outlines a novel community-led methodology - a community sandpit - to address the inclusion of ethnic groups in public involvement in research, reports on its evaluation, findings, legacy and impact. METHODS: Through detailed planning - thinking through and taking into account all stakeholders perspectives in the planning and design of the sandpit, relationship-building, co-design and co-delivery between the Public Programmes team based at Manchester University NHS Foundation Trust and the Greater Manchester Black and Minority Ethnic Network - the community sandpit was held in July 2018. RESULTS: Fifteen community organisations took part in the two-day event, as well as six researchers, and six creative practitioners. Six community-based partnership projects were seed-funded; four of these received additional funding from other sources also. CONCLUSIONS: Evaluation of the sandpit showed the format to be well-received by all: it levelled power relationships between community organisations, health researchers and research infrastructure; it developed capacity amongst researchers about the accessibility, role and potential of community organisations. Described as "not another community seed fund" by community partners, the sandpit offered community partners, equitable avenues for collaboration within Greater Manchester translational research and led to the formation of the Black, Asian and Minority Ethnic Research Advisory Group (BRAG Vocal Website information, - https://www.wearevocal.org/opportunities/black-asian-and-minority-ethnic-research-advisory-group-brag/ , 2021). The method has the potential to be replicated elsewhere to support inclusive public involvement in research and inclusive research.


Public involvement in "bench to bedside" research (from laboratory-based research to clinical practice) is increasingly recognised as essential for relevant and reliable research. To enable the findings from health research to meet the needs of those who stand to benefit from it the most and to ensure that differences in health and disease are reduced as much as possible, public involvement must be diverse and inclusive. Recent reports, however, indicate that public involvement is exclusive, including in its interactions with racially minoritised groups. This paper outlines a novel community-led methodology ­ a community sandpit ­ to address the inclusion of ethnic groups in public involvement in research, reports on its evaluation, findings, legacy and impact.Through detailed planning ­ thinking through and taking into account all stakeholders perspectives in the planning and design of the sandpit, relationship-building, co-design and co-delivery between the Public Programmes Team (now Vocal) based at Manchester University NHS Foundation Trust worked with the Greater Manchester Black and Minority Ethnic Network - the community sandpit was held in July 2018. Fifteen community organisations took part in the two-day event, as well as six researchers, and six creative practitioners (artists with experience of working with the public on socially engaged projects to engage them in areas such as science). Six community-based partnership projects were seed-funded; four of these received additional funding from other sources. Evaluation of the sandpit showed the format to be well-received by all: it levelled power relationships between community organisations, health researchers and research infrastructure; it increased researchers knowledge and insights about the accessibility of community organisations and of how they might work effectively with them. Described as "not another community seed fund" by community partners, the sandpit began the process of levelling the playing field for collaboration between Greater Manchester translational research and local community organisations and led to the formation of the Black, Asian and Minority Ethnic Research Advisory Group (BRAG) (Vocal Website information, - https://www.wearevocal.org/opportunities/black-asian-and-minority-ethnic-research-advisory-group-brag/ , 2021). The method has the potential to be repeated elsewhere to support inclusive public involvement in research and inclusive research.

2.
Mol Cancer ; 8: 62, 2009 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-19671192

RESUMO

BACKGROUND: We have demonstrated that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis in oral squamous cell carcinoma (SCC). Chemotherapy is a powerful tool for the treatment of oral cancer, including oral SCC; however, the effects of chemotherapeutic agents on the expression of CXCR4 are unknown. In this study, we examined the expression of CXCR4 associated with the chemotherapeutic agents in oral cancer cells. RESULTS: The expression of CXCR4 was examined using 3 different chemotherapeutic agents; 5-fluorouracil, cisplatin, and vesnarinone (3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2-(1H)-quinolinone) in B88, a line of oral cancer cells that exhibits high levels of CXCR4 and lymph node metastatic potential. Of the 3 chemotherapeutic agents that we examined, only vesnarinone downregulated the expression of CXCR4 at the mRNA as well as the protein level. Vesnarinone significantly inhibited lymph node metastasis in tumor-bearing nude mice. Moreover, vesnarinone markedly inhibited 2.7-kb human CXCR4 promoter activity, and we identified the transcription factor, Krüppel-like factor 2 (KLF2), as a novel vesnarinone-responsive molecule, which was bound to the CXCR4 promoter at positions -300 to -167 relative to the transcription start site. The forced-expression of KLF2 led to the downregulation of CXCR4 mRNA and impaired CXCR4 promoter activity. The use of siRNA against KLF2 led to an upregulation of CXCR4 mRNA. CONCLUSION: These Results indicate that vesnarinone downregulates CXCR4 via the upregulation of KLF2 in oral cancer.


Assuntos
Fatores de Transcrição Kruppel-Like/genética , Neoplasias Bucais/tratamento farmacológico , Quinolinas/farmacologia , Receptores CXCR4/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cisplatino/farmacologia , Regulação para Baixo/efeitos dos fármacos , Citometria de Fluxo , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HeLa , Humanos , Fatores de Transcrição Kruppel-Like/metabolismo , Luciferases/genética , Luciferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas/genética , Pirazinas , Interferência de RNA , Receptores CXCR4/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Mol Cancer Res ; 5(7): 685-94, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17634424

RESUMO

We have previously shown that a stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis, but not in that of distant metastasis, in oral squamous cell carcinoma (SCC). In this study, we investigated the role of the autocrine SDF-1/CXCR4 system, with a focus on distant metastasis in oral SCC cells. The immunohistochemical staining of SDF-1 and CXCR4 using primary oral SCCs and metastatic lymph nodes showed a significantly higher number of SDF-1-positive cases among the metastatic lymph nodes than among the primary oral SCCs, which was associated with a poor survival rate among those of the former group. The forced expression of SDF-1 in B88 cells, which exhibit functional CXCR4 and lymph node metastatic potential (i.e., the autocrine SDF-1/CXCR4 system), conferred enhanced cell motility and anchorage-independent growth potential onto the cells. Orthotopic inoculation of the transfectant into nude mice was associated with an increase in the number of metastatic lymph nodes and more aggressive metastatic foci in the lymph nodes. Furthermore, the SDF-1 transfectant (i.e., the autocrine SDF-1/CXCR4 system) exhibited dramatic metastasis to the lung after i.v. inoculation, whereas the mock transfectant (i.e., the paracrine SDF-1/CXCR4 system) did not. Under the present conditions, AMD3100, a CXCR4 antagonist, significantly inhibited the lung metastasis of the SDF-1 transfectant, ameliorated body weight loss, and improved the survival rate of tumor-bearing nude mice. These results suggested that, in cases of oral SCC, the paracrine SDF-1/CXCR4 system potentiates lymph node metastasis, but distant metastasis might require the autocrine SDF-1/CXCR4 system.


Assuntos
Comunicação Autócrina , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Quimiocinas CXC/metabolismo , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Receptores CXCR4/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Comunicação Autócrina/efeitos dos fármacos , Benzilaminas , Quimiocina CXCL12 , Ciclamos , Feminino , Compostos Heterocíclicos/farmacologia , Humanos , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Fenótipo , Receptores CXCR4/antagonistas & inibidores , Análise de Sobrevida
4.
Int J Oncol ; 29(5): 1133-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17016644

RESUMO

Epithelial-mesenchymal transition (EMT) refers to critical events occasionally observed during tumor progression, including invasion and metastasis, by which cancer cells acquire a fibroblast-like phenotype. Since the stromal cell-derived factor-1 (SDF-1)/CXCR4 system can facilitate lymph node metastasis in oral squamous cell carcinoma (SCC), we have explored the possibility that this system might be involved in EMT. Oral SCC cells, B88 and HNt, which have functional CXCR4 and lymph node metastatic potential, were found to lose their epithelial cell morphology due to SDF-1. In this context, the downregulation of epithelial markers, cytokeratin, E-cadherin and beta-catenin, and the upregulation of mesenchymal marker, vimentin and snail were detected. Furthermore, upregulation of vimentin by treatment with SDF-1 was impaired by phosphatidylinositol 3 kinase (PI3K) inhibitor Wortmannin, but not by mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor U0126. In the type I collagen embedding culture, SDF-1-treated B88 cells formed protruding extensions, but the effect was impaired by treatment with Wortmannin. These results suggested that EMT induced by the SDF-1/CXCR4 system might be involved in the lymph node metastasis of oral SCCs via activation of PI3K-Akt/PKB pathway.


Assuntos
Carcinoma de Células Escamosas/secundário , Quimiocinas CXC/metabolismo , Mesoderma/patologia , Neoplasias Bucais/patologia , Receptores CXCR4/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Técnicas de Cultura de Células , Quimiocina CXCL12 , Quimiocinas CXC/farmacologia , Regulação para Baixo , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Epitélio/patologia , Humanos , Metástase Linfática , Mesoderma/química , Mesoderma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/agonistas , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima , Vimentina/metabolismo
5.
Jpn J Infect Dis ; 59(2): 85-91, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16632907

RESUMO

During the febrile illness epidemic in Bangladesh in 2002, 58 people died out of the 6,132 affected. Two hundred hospitalized patients were analyzed clinically, serologically and virologically to determine the features of this dengue infection. Among the 10- to 70-year-old age group of the 200 clinically suspected dengue patients, 100 (50%) were confirmed as dengue cases by virus isolation and dengue IgM-capture ELISA. Of the 100 dengue-confirmed cases, the mean age was 29.0 (+/-12.4). The possible dengue secondary infection rate determined by Flavivirus IgG-indirect ELISA was 78% in 2002. Eight dengue virus strains were isolated, representing the first dengue virus isolation in the country, and all of the strains were dengue virus type-3 (DEN-3). Sequence data for the envelope gene of the DEN-3 Bangladeshi isolates were used in a phylogenetic comparison with DEN-3 from other countries. A phylogenetic analysis revealed that all 8 strains of DEN-3 were clustered within a well-supported independent sub-cluster of genotype II and were closely related to the Thai isolates from the 1990s. Therefore, it is likely that the currently circulating DEN-3 viruses entered Bangladesh from neighboring countries.


Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Dengue/virologia , Surtos de Doenças , Filogenia , Adolescente , Adulto , Fatores Etários , Idoso , Bangladesh/epidemiologia , Sequência de Bases , Criança , Dengue/epidemiologia , Vírus da Dengue/imunologia , Vírus da Dengue/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Lab Invest ; 84(12): 1538-46, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15492752

RESUMO

Recently, it has been suggested that chemokine/receptor interactions determine the destination of the invasive tumor cells in several types of cancer. It has also been proposed that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system might be involved lymph node metastasis in oral squamous cell carcinoma (SCC). In order to further clarify the role of the SDF-1/CXCR4 system in oral SCC, we generated CXCR4 stable transfectants (IH-CXCR4) using oral SCC cells, and compared them to IH, which did not express CXCR4 and which did not have lymph node metastatic potentials in vivo. We introduced enhanced green fluorescent protein (GFP) fused-CXCR4 into IH cells, and detected the GFP fluorescence in the cytoplasm and cell membrane in approximately 60% of the G418-resistant cells. This bulk-transfectant expressed a high level of CXCR4 mRNA and protein, and exhibited the characteristic calcium fluxes and chemotactic activity observed in treatment with SDF-1. SDF-1 biphasically activated extracellular signal-regulated kinase (ERK)1/2, but continuously activated Akt/protein kinase B (PKB) in IH-CXCR4 cells. Most importantly, IH-CXCR4 cells frequently metastasized to the cervical lymph node, but not to the distant organs in the orthotopic inoculation of nude mice. Furthermore, these lymph node metastases were inhibited by the treatment of a mitogen-activated protein kinase/ERK kinase inhibitor, U0126, or a phosphatidylinositol 3 kinase inhibitor, wortmannin. These results indicate that SDF-1/CXCR4 signaling mediates the establishment of lymph node metastasis in oral SCC via ERK1/2 or Akt/PKB pathway.


Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/genética , Receptores CXCR4/genética , Animais , Cálcio/fisiologia , Linhagem Celular Tumoral , Quimiocina CXCL12 , Quimiocinas CXC/genética , Proteínas de Fluorescência Verde/genética , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Transplante Heterólogo
7.
Int J Oncol ; 25(1): 65-71, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15201990

RESUMO

We have demonstrated the possibility that the stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system might be involved in the establishment of lymph node metastasis in oral squamous cell carcinoma (SCC). In order to further clarify the role of the SDF-1/CXCR4 system in oral SCC, we examined the expression of CXCR4 and SDF-1 in biopsy specimens from 61 patients with oral SCC by means of immunohistochemistry, and investigated several clinicopathological factors, including age, sex, lymph node metastasis, invasion, recurrence and prognosis. The expression of CXCR4 and SDF-1 was observed in 57.3 and 11.4% of our subjects, respectively. Although we were unable to find a statistically significant association between the expression of SDF-1 and any clinicopathological factors, we did find a significant association between the expression of CXCR4 and lymph node metastasis (P=0.0417). Moreover, the mode of invasion (P=0.0002) and recurrence of the tumors (P=0.0185) were strongly associated with CXCR4 expression, and the CXCR4-positive group showed a significantly poorer prognosis than the CXCR4-negative group (P=0.0401). Recombinant SDF-1alpha stimulated in vitro invasiveness and scattering in CXCR4-expressing oral SCC cells, but the treatment did not affect the expression of matrix metalloproteinases or urokinase-type plasminogen activator. These results indicate that SDF-1/CXCR4 signaling in oral SCC cells might be involved in the diverse action of oral SCC, including invasion or micrometastasis at the primary site and lymph node metastasis.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Receptores CXCR4/genética , Idoso , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/cirurgia , Linhagem Celular Tumoral , Quimiocina CXCL12 , Quimiocinas CXC/análise , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Neoplasias Bucais/cirurgia , Invasividade Neoplásica , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Exp Cell Res ; 290(2): 289-302, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14567988

RESUMO

We examined the role of chemokine signaling on the lymph node metastasis of oral squamous cell carcinoma (SCC) using lymph node metastatic (HNt and B88) and nonmetastatic oral SCC cells. Of 13 kinds of chemokine receptors examined, only CXCR4 expression was up-regulated in HNt and B88 cells. CXCR4 ligand, stromal-cell-derived factor-1alpha (SDF-1alpha; CXCL12), induced characteristic calcium fluxes and chemotaxis only in CXCR4-expressing cells. CXCR4 expression in metastatic cancer tissue was significantly higher than that in nonmetastatic cancer tissue or normal gingiva. Although SDF-1alpha was undetectable in either oral SCC or normal epithelial cells, submandibular lymph nodes expressed the SDF-1alpha protein, mainly in the stromal cells, but occasionally in metastatic cancer cells. The conditioned medium from lymphatic stromal cells promoted the chemotaxis of B88 cells, which was blocked by the CXCR4 neutralization. SDF-1alpha rapidly activated extracellular signal-regulated kinase (ERK)1/2 and Akt/protein kinase B (PKB), and their synthetic inhibitors attenuated the chemotaxis by SDF-1alpha. SDF-1alpha also activated Src family kinases (SFKs), and its inhibitor PP1 diminished the SDF-1alpha-induced chemotaxis and activation of both ERK1/2 and Akt/PKB. These results indicate that SDF-1/CXCR4 signaling may be involved in the establishment of lymph node metastasis in oral SCC via activation of both ERK1/2 and Akt/PKB induced by SFKs.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundário , Quimiocinas CXC/fisiologia , Neoplasias Bucais/patologia , Proteínas Serina-Treonina Quinases , Receptores CXCR4/fisiologia , Transdução de Sinais , Animais , Western Blotting , Cálcio/metabolismo , Movimento Celular , Quimiocina CXCL12 , Ensaio de Imunoadsorção Enzimática , Humanos , Metástase Linfática , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Bucais/metabolismo , Fosforilação , Testes de Precipitina , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt
9.
Oral Oncol ; 39(8): 855-61, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-13679209

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. Recently, we have demonstrated that PPARgamma is expressed in human salivary gland tumors and its ligands inhibit the growth of cultured salivary gland cancer cells. However, expression and function of PPARgamma in normal and neoplastic human oral squamous epithelium remains unclear. In the present study, we examined PPARgamma expression in human oral squamous cell carcinoma (OSCC) and tested its ligands for any antitumor effect. PPARgamma mRNA was detected by RT-PCR in some OSCC tissues and cultured cells, but the PPARgamma protein showed neither expression nor ligand-induced transcriptional activity. Despite loss of PPARgamma function, synthetic PPARgamma ligands caused significant dose-dependent inhibition of cancer cell growth. These results suggest that PPARgamma function is inactivated in OSCC cells and the anti-proliferative effect of its synthetic ligands is independent of PPARgamma.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Tiazolidinedionas/uso terapêutico , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Cromanos/uso terapêutico , Análise Mutacional de DNA , Humanos , Neoplasias Bucais/metabolismo , Pioglitazona , RNA Mensageiro/análise , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção/métodos , Troglitazona
10.
Biochem Biophys Res Commun ; 305(4): 846-54, 2003 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-12767908

RESUMO

TSC-22 gene was composed of three exons and its length was approximately 5.5 kb including 2.9 kb promoter region. The transcription starting site was located at 7 and 29 bp downstream from TATA box. Promoter analysis revealed that 2146 bp of TSC-22 promoter was activated by several differentiation inducing drugs. Although originally TSC-22 was isolated as a TGF-beta-inducible gene, TSC-22 promoter was not activated by the enhanced TGF-beta signaling. We found 3 copies of the Shaw-Kamens sequence (AUUUA) in the human TSC-22 mRNA 3'-UTR and identified three proteins (40, 20, and 15 kDa) which bound to this. Only the 40 kDa protein-RNA complex was decreased by treatment with TGF-beta 1. Moreover, the TSC-22 mRNA 3'-UTR destabilized the heterologous luciferase mRNA, but the destabilization was recovered with TGF-beta 1. These observations suggest that up-regulation of TSC-22 mRNA by TGF-beta 1 is achieved by mRNA stabilization, but not by transcriptional activation.


Assuntos
Estabilidade de RNA , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta/farmacologia , Regiões 3' não Traduzidas , Sequência de Bases , Linhagem Celular , Células HeLa , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Elementos de Resposta , Fatores de Transcrição/metabolismo , Sítio de Iniciação de Transcrição , Ativação Transcricional , Fator de Crescimento Transformador beta1
11.
Biochem Biophys Res Commun ; 292(4): 957-63, 2002 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-11944908

RESUMO

We transfected a salivary gland cancer cell line, TYS, with three different forms of TSC-22 (transforming growth factor-beta-stimulated clone-22) gene: full-length TSC-22 (TSC-22FL) containing nuclear export signal, TSC-box and leucine zipper, truncated TSC-22 (TSC-22LZ) containing only TSC-box and leucine zipper, and truncated TSC-22 with nuclear localization signal (NLS-TSC-22LZ). High expression of TSC-22FL in the cytoplasm markedly enhanced the radiation-sensitivity of TYS cells, while, moderate expression of TSC-22FL marginally affected the radiation-sensitivity. TSC-22LZ, which was expressed in the cytoplasm and the nucleus, enhanced the radiation-sensitivity of TYS cells irrespective to its expression level. NLS-TSC-22LZ, which was expressed only in the nucleus, marginally affected the radiation-sensitivity of the cells even at high expression level. Interestingly, cytoplasmic TSC-22 translocates to nucleus concomitant with radiation-induced apoptosis. These results suggest that cytoplasmic localization of TSC-22 and translocation of TSC-22 from cytoplasm to nucleus is important for regulating the cell death signal after irradiation-induced DNA damage.


Assuntos
Tolerância a Radiação/efeitos dos fármacos , Proteínas Repressoras/farmacologia , Neoplasias das Glândulas Salivares/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Transporte Ativo do Núcleo Celular/efeitos da radiação , Motivos de Aminoácidos/fisiologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos da radiação , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Núcleo Celular/metabolismo , Núcleo Celular/efeitos da radiação , Citoplasma/metabolismo , Citoplasma/efeitos da radiação , Proteínas de Fluorescência Verde , Humanos , Zíper de Leucina/fisiologia , Proteínas Luminescentes/genética , Sinais de Localização Nuclear/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/genética , Neoplasias das Glândulas Salivares/tratamento farmacológico , Deleção de Sequência , Transfecção , Células Tumorais Cultivadas
12.
Int J Oncol ; 20(3): 599-605, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11836575

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. It is expressed in several tissue types, including adipose tissue in which it stimulates adipogenesis. Recent studies have demonstrated that PPARgamma ligands induce cellular differentiation and inhibit cell growth in carcinomas of various organs including the breast, prostate, lung, colon, stomach, bladder, and pancreas. However, whether PPARgamma is expressed in human salivary gland tumors and its function in this tissue is unknown. In the present study, we examined PPARgamma gene expression in human salivary gland cancer cells and tested its ligands for any antitumor effect. PPARgamma mRNA was detected by RT-PCR in both benign and malignant salivary gland tumor tissues. The effect of PPARgamma on cell growth was investigated using four human salivary gland cancer cell lines; HSG, AZA3, HSY and TYS, which were confirmed to express PPARgamma1 mRNA and protein. Retinoid X receptor alpha protein, which forms heterodimers with PPARgamma, was also detected in all the cells tested. Data obtained by luciferase assay indicated that the intrinsic PPARgamma protein was activated by the synthetic ligands, troglitazone and pioglitazone, but not by the natural ligand, 15-deoxy-delta12, 14-prostaglandin J2. The synthetic PPARgamma ligands, particularly troglitazone, caused significant dose-dependent inhibition of cancer cell growth. Furthermore, the overexpression of PPARgamma1 or PPARgamma2 in cancer cells also reduced significantly their growth rate. These results suggest that PPARgamma and its synthetic ligands suppress the growth of human salivary gland cancer cells and it may be a useful molecular target for cancer treatment.


Assuntos
Receptores Citoplasmáticos e Nucleares/biossíntese , Receptores Citoplasmáticos e Nucleares/genética , Neoplasias das Glândulas Salivares/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Western Blotting , Divisão Celular , DNA Complementar/metabolismo , Vetores Genéticos , Humanos , Ligantes , Luciferases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
13.
Oncol Rep ; 9(2): 371-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11836610

RESUMO

Several investigators have demonstrated that TGF-beta stimulated clone-22 (TSC-22) regulates cell growth and differentiation, and cell death. TSC-22 is a putative transcriptional regulator containing a leucine zipper-like structure and a nuclear export signal. We previously showed the cytoplasmic localization of TSC-22 and the nuclear translocation of TSC-22 concomitant with induction of apoptosis in salivary gland cancer cells. In the present study, we attempted to identify the active domain of TSC-22 protein that regulated the biological functions of TSC-22. We constructed three mammalian expression vectors, which could produce full length TSC-22 only in cytoplasm, the leucine zipper structure of TSC-22 in both cytoplasm and nucleus, and the leucine zipper structure only in nucleus. Then, we transfected a salivary gland cancer cell line, HSG with these expression vectors, and investigated the growth profile of the transfectants. None of the TSC-22 constructs inhibited the monolayer growth and the anchorage-dependent colony formation of HSG cells. However, the leucine zipper structure of TSC-22 markedly inhibited the anchorage-independent colony formation of HSG cells (p<0.001; one way ANOVA). Full length TSC-22 also suppressed the anchorage-independent colony formation of HSG cells, although the effect of full length TSC-22 was much lower than those of the leucine zipper constructs. These observations suggest that the leucine zipper structure in TSC-22 protein is an active domain that negatively regulates the growth of salivary gland cancer cells.


Assuntos
Zíper de Leucina/fisiologia , Proteínas Repressoras/fisiologia , Neoplasias das Glândulas Salivares/patologia , Motivos de Aminoácidos/fisiologia , Adesão Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Primers do DNA , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/genética , Sinais de Localização Nuclear/fisiologia , Plasmídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Neoplasias das Glândulas Salivares/terapia , Transfecção , Células Tumorais Cultivadas
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