Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Cancer Sci ; 99(11): 2230-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18823381

RESUMO

Mitochondrial DNA (mtDNA) repair systems are thought to be associated with the susceptibility of cancer cells to anticancer agents. The present study investigated the relationship between the susceptibility to gamma-rays and the mtDNA repair ability of oral squamous cell carcinoma (OSC) cell lines. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and mtDNA common deletion in both nuclear and mitochondrial DNA of OSC-2, OSC-3 and OSC-6 cells (radio-sensitive cell lines) after gamma-ray-irradiation were higher than those of OSC-1, OSC-4 and OSC-5 cells (radio-resistant cell lines). Compared with OSC-2, OSC-3 and OSC-6 cells, OSC-1, OSC-4 and OSC-5 cells had higher levels of activity of phosphoinositide-3 kinase (PI-3K)/Akt and more strongly expressed 8-hydroxyguanine DNA glycosylase (OGG1), DNA polymerase gamma (POLG) and mitochondrial transcription factor A (Tfam). Down-regulation of these mtDNA-repair-associated molecules by the RNA interference technique enhanced the susceptibility of OSC-2 and OSC-5 cells to gamma-rays, and the expression of Tfam and POLG was down-regulated by inhibitors of PI-3K/Akt signaling. These results indicate that the inhibition of mtDNA repair capacity by PI-3K/Akt signal inhibitors and OGG1 down-regulator in cancer cells may be a useful strategy for cancer treatment when combined with ionizing irradiation and chemotherapeutic drugs.


Assuntos
Apoptose , Carcinoma de Células Escamosas/metabolismo , Reparo do DNA , DNA Mitocondrial/metabolismo , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , DNA Polimerase gama , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Regulação para Baixo , Raios gama , Humanos , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Transdução de Sinais , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo
2.
Biochem Biophys Res Commun ; 366(2): 301-7, 2008 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-18035043

RESUMO

Reactive oxygen species (ROS) have important roles in various physiological processes. Recently, several novel homologues of the phagocytic NADPH oxidase have been discovered and this protein family is now designated as the Nox family. We investigated the involvement of Nox family proteins in ionizing irradiation-induced ROS generation and impairment in immortalized salivary gland acinar cells (NS-SV-AC), which are radiosensitive, and immortalized ductal cells (NS-SV-DC), which are radioresistant. Nox1-mRNA was upregulated by gamma-ray irradiation in NS-SV-AC, and the ROS level in NS-SV-AC was increased to approximately threefold of the control level after 10Gy irradiation. The increase of ROS level in NS-SV-AC was suppressed by Nox1-siRNA-transfection. In parallel with the suppression of ROS generation and Nox1-mRNA expression by Nox1-siRNA, ionizing irradiation-induced apoptosis was strongly decreased in Nox1-siRNA-transfected NS-SV-AC. There were no large differences in total SOD or catalase activities between NS-SV-AC and NS-SV-DC although the post-irradiation ROS level in NS-SV-AC was higher than that in NS-SV-DC. In conclusion, these results indicate that Nox1 plays a crucial role in irradiation-induced ROS generation and ROS-associated impairment of salivary gland cells and that Nox1 gene may be targeted for preservation of the salivary gland function from radiation-induced impairment.


Assuntos
Apoptose/efeitos da radiação , NADH NADPH Oxirredutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Glândulas Salivares/metabolismo , Glândulas Salivares/efeitos da radiação , Transdução de Sinais/fisiologia , Superóxidos/metabolismo , Animais , Linhagem Celular , Relação Dose-Resposta à Radiação , Raios gama , NADPH Oxidase 1 , Doses de Radiação , Glândulas Salivares/citologia , Transdução de Sinais/efeitos da radiação
3.
Cancer Res ; 66(10): 5251-7, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16707450

RESUMO

Although adherent junctions have been extensively studied, the role of tight junctions in cancer cell invasion is not sufficiently explored. We investigated whether claudin-1, a component of tight junctions, regulated invasion activity in oral squamous cell carcinoma (OSC) cells. The expression of claudin-1, activity of matrix metalloproteinase (MMP)-2, and cleavage of laminin-5 gamma2 chains were assessed by Western blot analysis, immunohistochemistry, and zymography in OSC cell lines (OSC-4 and NOS-2, highly invasive; OSC-7, weakly invasive) and their xenografts in severe combined immunodeficient (SCID) mice. The influence of claudin-1 small interfering RNA (siRNA) on the invasion activity of the cell lines was also investigated. Compared with OSC-7, both OSC-4 and NOS-2 more strongly expressed claudin-1 and possessed high activities of MMP-2 and MMP-9. Tumors formed in the tongues of SCID mice xenografted with OSC-4, NOS-2, and OSC-7 immunohistochemically revealed strong, moderate, and weak expression of laminin-5 gamma2 chains, respectively, and laminin-5 gamma2 chains were secreted in the conditioned medium of the cancer cells in parallel with the in vivo results. Claudin-1 siRNA largely suppressed the invasion of OSC-4 and decreased the activation of MMP-2, the expression of membrane-type MMP-1 (MT1-MMP), and the cleavage of laminin-5 gamma2. In addition, not only antibodies against MT1-MMP and epidermal growth factor receptor (EGFR) but also MMP-2 and EGFR inhibitors strongly suppressed the invasion activity of OSC-4. These results suggest that claudin-1 up-regulates cancer cell invasion activity through activation of MT1-MMP and MMP-2, which results in enhanced cleavage of laminin-5 gamma2 chains.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Laminina/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz/metabolismo , Proteínas de Membrana/biossíntese , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Animais , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Claudina-1 , Claudina-4 , Humanos , Imuno-Histoquímica , Masculino , Metaloproteinase 14 da Matriz , Metaloproteinases da Matriz Associadas à Membrana , Proteínas de Membrana/genética , Camundongos , Camundongos SCID , Neoplasias Bucais/genética , Invasividade Neoplásica , Transplante de Neoplasias , Ocludina , RNA Interferente Pequeno/genética , Fatores de Transcrição da Família Snail , Neoplasias da Língua/genética , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Transplante Heterólogo , Regulação para Cima
4.
Oral Oncol ; 42(9): 873-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16730473

RESUMO

We examined the effect of concomitant chemo-radio-immunotherapy on 80 patients with tongue carcinoma. Disappearance of the tumor without recurrence was observed in 21 patients (38.9%) in intravenous infusion chemotherapy group (A) and in 20 patients (76.9%) in intra-arterial infusion chemotherapy group (B) (P<0.005). A total of 41 patients (51.3%) were free from the tumor after the combined therapy. Along with the good therapeutic effect, oral function was preserved with minimal impairment of speech and mastication. Tumor stage, the mode of tumor cell invasion and tumor cell differentiation were not correlated with the therapeutic effect. In addition, the expression of p53, p21(Cip1/WAF1) and proliferating cell nuclear antigen did not differ between the patients with lethal and non-lethal effects. The 5-year-survival rate was 56.8% in Group A, 76.9% in Group B and 59.6% overall. Thus, combined chemo-radio-immunotherapy, especially intra-arterial infusion, may bring a universal therapeutic effect in tongue carcinoma regardless of the tumor stage and the expression of cell phase-regulating proteins.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias da Língua/terapia , Idoso , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/fisiopatologia , Morte Celular , Terapia Combinada , Inibidor de Quinase Dependente de Ciclina p21/análise , Feminino , Humanos , Imuno-Histoquímica , Imunoterapia , Masculino , Mastigação , Pessoa de Meia-Idade , Antígeno Nuclear de Célula em Proliferação/análise , Estudos Retrospectivos , Medida da Produção da Fala , Taxa de Sobrevida , Neoplasias da Língua/patologia , Neoplasias da Língua/fisiopatologia , Resultado do Tratamento , Proteína Supressora de Tumor p53/análise
5.
J Med Microbiol ; 54(Pt 5): 493-496, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15824430

RESUMO

Aspiration of oropharyngeal bacteria and fungi is occasionally suspected in patients with pneumonia. A patient with oral carcinoma underwent chemoradioimmunotherapy and, about 4 weeks from the start of the therapy, the patient suffered from severe oral mucositis induced by chemoradiotherapy, and candidal pneumonia was subsequently induced. The candidal pneumonia was insufficiently improved by potent antifungal drugs, taking a lethal course. Randomly amplified polymorphic DNA analysis and DNA sequence examination of strains isolated from the oral cavity 1 week before the onset of pneumonia and autopsied lung revealed the identity of both strains as Candida albicans, and the DNA analysis supported aspiration of oral Candida. These results indicate that the pathogen of the pneumonia, C. albicans, was aspirated from the oral cavity and that oral Candida is easily aspirated and becomes the pathogen of pneumonia.


Assuntos
Candida albicans/isolamento & purificação , Candidíase/etiologia , Pneumonia Aspirativa/etiologia , Aerossóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Antineoplásicos/uso terapêutico , Sequência de Bases/genética , Candida albicans/genética , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Candidíase Bucal/induzido quimicamente , Candidíase Bucal/complicações , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/terapia , DNA Fúngico/genética , Evolução Fatal , Feminino , Fluconazol , Humanos , Miconazol/uso terapêutico , Neoplasias Bucais/complicações , Neoplasias Bucais/terapia , Pneumonia Aspirativa/tratamento farmacológico , Pneumonia Aspirativa/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico
6.
Cancer Lett ; 274(2): 187-93, 2009 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-18986760

RESUMO

Recent clinical studies have indicated that intra-tumoral gene expression levels of 5-fluorouracil (5-FU) metabolism-related enzymes may predict the clinical response of several cancers to 5-FU-based chemotherapy. However, few studies examining oral squamous cell carcinomas (OSCCs) have been reported. In this study, we determined the expression levels of 5-FU metabolism-related enzymes like thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylate (TP) and orotate phosphoribosyl transferase (OPRT) using reverse transcription-polymerase chain reaction (RT-PCR) combined with laser capture microdissection (LCM). We also evaluated the correlation between the mRNA expressions of these genes and clinico-pathological factors or the treatment effects of 5-FU-based chemotherapy combined with radiotherapy in 27 patients with OSCC. No significant correlation was observed between the mRNA expression levels of any of the examined genes and the T-stage, N-stage, differentiation grade or mode of tumor invasion. Although TS and OPRT mRNA were not correlated with the histopathological effects and the development of tumor recurrence, DPD and TP mRNA were significantly correlated with the histopathological effects and tumor recurrence. A significant positive correlation was also observed between the expression of TS and DPD mRNA, but no other correlations were observed among the other genes. Our results suggest that the combined evaluation of TP and DPD mRNA expression in tumor cells using LCM and RT-PCR may be a useful predictor of the efficacy of 5-FU-based chemotherapy combined with radiotherapy in patients with OSCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/enzimologia , Di-Hidrouracila Desidrogenase (NADP)/genética , Fluoruracila/uso terapêutico , Neoplasias Bucais/enzimologia , RNA Mensageiro/genética , Timidina Fosforilase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Humanos , Pessoa de Meia-Idade , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Neoplasias Bucais/radioterapia , Recidiva Local de Neoplasia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
J Antimicrob Chemother ; 57(1): 94-103, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16291868

RESUMO

OBJECTIVES: To establish a novel strategy of fungal infection control. METHODS: We examined the influences of antimicrobial peptides including a synthesized short lactoferrin peptide (FKCRRWQWRM, Peptide 2; Pep2) on the synthesis of Candida cell wall polysaccharides, ergosterol synthesis, membrane permeability and the efflux of ATP. RESULTS: Colony formation of Candida albicans was synergistically suppressed by a combination of low concentrations of each drug and peptide. All peptides and amphotericin B, but not itraconazole, revealed weak inhibitory activities against ergosterol synthesis and the peptides weakly suppressed the synthesis of Candida cell wall components, glucan, mannan and chitin. Cell membrane permeability was not only increased by these peptides but also clearly increased by both amphotericin B and itraconazole. ATP efflux was however up-regulated by low concentrations of the peptides, especially by Pep2 and Hst5, although both antifungal drugs did not exert any influence on ATP efflux. The expression of the Candida drug resistance genes 1 and 2 (CDR1 and CDR2) was increased by both drugs, but this increase was suppressed by each peptide. In addition, larger amounts of amphotericin B and itraconazole remained in Candida cells in the presence of Pep2 or Hst5 due to the lower excretion. The effects of both peptides on ATP efflux and increase of intercellular amphotericin B and itraconazole were blocked by anion channel inhibitors 4,4'-diisothiocyanatestilbene-2, 2'-disulphonic acid and 5-nitro-2-(3-phenylpropylamino) benzoic acid. CONCLUSIONS: The examined peptides, especially Pep2 and Hst5, enhance the candidacidal activity of antifungal drugs by promoting anion channel-associated ATP efflux from Candida cells and decreasing efflux of the drugs, which could be useful clinical applications.


Assuntos
Trifosfato de Adenosina/metabolismo , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Lactoferrina/farmacologia , Fragmentos de Peptídeos/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , Farmacorresistência Fúngica/efeitos dos fármacos , Farmacorresistência Fúngica/genética , Sinergismo Farmacológico , Ergosterol/metabolismo , Proteínas Fúngicas/genética , Expressão Gênica/efeitos dos fármacos , Lactoferrina/química , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Fragmentos de Peptídeos/química , Polissacarídeos Bacterianos/metabolismo
8.
Immunology ; 110(2): 217-24, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14511235

RESUMO

Investigation of the induction of apoptosis by cytotoxic lymphocytes has mainly focused on the signalling associated with Fas and its adaptor proteins. The signal pathway via mitochondria, however, has not been sufficiently elucidated in cytotoxic lymphocyte-induced apoptosis. We examined the release of mitochondrial proapoptotic factors by lymphokine-activated killer (LAK) cells in two cell lines. LAK cell-induced DNA fragmentation of the target cells was suppressed to approximately 50% of control levels by the addition of neutralizing monoclonal antibody to Fas and a granzyme B inhibitor. When intracellular reactive oxygen species (ROS) were scavenged, the LAK cell-induced DNA fragmentation was decreased to approximately 60% of the non-treated cell level. Co-cultivation of Daudi cells with LAK cells increased cytosolic and mitochondrial ROS levels. Activation of procaspase-3 and apoptosis by treatment of oral squamous cell carcinoma cells (OSC) with LAK cells was partially inhibited by pretreatment of OSC cells with ROS scavengers and mitochondrial complex inhibitors. Furthermore, cytochrome c and apoptosis-inducing factor (AIF) were released from mitochondria by OSC cell treatment with supernatants of LAK cells. The supernatant-induced cytochrome c release was suppressed by mitochondrial complex inhibitors, but the inhibitors did not inhibit the release of AIF. These results indicate that LAK cells induce target cell apoptosis via not only the Fas/Fas ligand system and granzyme B, but also ROS-dependent cytochrome c and ROS-independent AIF release.


Assuntos
Apoptose/imunologia , Carcinoma de Células Escamosas/imunologia , Interleucina-2/imunologia , Células Matadoras Ativadas por Linfocina/imunologia , Espécies Reativas de Oxigênio/imunologia , Fator de Indução de Apoptose , Grupo dos Citocromos c/metabolismo , Fragmentação do DNA/imunologia , Flavoproteínas/metabolismo , Granzimas , Humanos , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina Endopeptidases/imunologia , Células Tumorais Cultivadas , Receptor fas/imunologia
9.
Int J Cancer ; 103(6): 717-22, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12516089

RESUMO

The influence of tyrosine nitration of cytochrome c and caspase 3 on apoptosis induction was investigated in an established squamous carcinoma cell line, OSC-4. The intracellular NO and O2(-) levels were increased up to about 110-120% and 140-180% of the control levels, respectively, after the treatment of OSC-4 cells with 5-FU (100 microg/ml), PLM (10 microg/ml), CDDP (10 microg/ml), or gamma-rays (20 Gy). The treatment of OSC-4 cells with ONOO(-) (1 mM) and the above anticancer agents induced tyrosine nitration of 14, 32 kDa protein among others and nitration of tyrosine residues of cytochrome c and caspase 3 was identified by the Western blotting of immunoprecipitates obtained by antibodies to these proapoptotic proteins. When cytochrome c and procaspase 3 were treated with ONOO(-), tyrosine nitration was increased in a ONOO(-)-dose dependent manner. Tyrosine nitration of cleaved (17 kDa) caspase 3, however, was not induced by ONOO(-). Procaspase 3 in the cytosol of HeLa cells was activated by the addition of ONOO(-)-treated as well as ONOO(-)-untreated cytochrome c. In addition, cleavage of ICAD and PARP were not suppressed in OSC-4 cells by pretreatment with ONOO(-). Activity of cleaved caspase 3 was not suppressed at low concentrations or by treatment with ONOO(-) or NO donors, SIN-1 and SNP. Furthermore, apoptosis of OSC-4 cells by the anticancer agents was not suppressed by ONOO(-). In conclusion, these results suggest that nitration of tyrosine residues of cytochrome c and procaspase 3 is induced by chemoradiotherapy but their nitration does not suppress cancer cell apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Caspases/metabolismo , Grupo dos Citocromos c/metabolismo , Neoplasias Bucais/patologia , Tirosina/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Carcinoma de Células Escamosas/embriologia , Caspase 3 , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática , Precursores Enzimáticos/metabolismo , Células HeLa/efeitos dos fármacos , Células HeLa/efeitos da radiação , Humanos , Neoplasias Bucais/enzimologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitrosação , Ácido Peroxinitroso/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Testes de Precipitina , Superóxidos/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/efeitos da radiação
10.
J Oral Pathol Med ; 31(2): 109-16, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11896833

RESUMO

BACKGROUND: The excretion of medicated drugs into saliva may disturb the oral environment and antibiotic excretion into saliva appears to be regulated by many factors that have not been fully explored. METHODS: Excretion of four cephem antibiotics into saliva was examined in healthy volunteers and rats, using high-performance liquid chromatography, and the relationship between excretion levels and plasma protein-binding activities of the antibiotics was investigated. RESULTS: Following addition of 50 microgram/ml of each antibiotic to human plasma, protein binding rates (PBRs) of cefuzonam (CZON, molecular weight (MW): 535.58), cefotaxime (CTX, MW: 477.45), flomoxef (FMOX, MW: 518.45) and cefozopran (CZOP, MW: 551.99) were 87.8 +/- 1.2, 70.8 +/- 0.8, 36.2 +/- 0.5 and 8.3 +/- 0.3%, respectively. In rat plasma, PBRs of the four antibiotics were 94.0 +/- 0.5, 62.1 +/- 1.4, 54.0 +/- 0.8 and 6.0 +/- 0.8%, respectively. Similar PBRs were observed when the antibiotic concentration was increased to 100 and 200 microgram/ml. CZOP was most rapidly excreted into saliva and had the highest concentration in saliva among the tested antibiotics, while the plateau level of CZON was the lowest. The excreted levels of each antibiotic in saliva, when locally perfused through the rat facial artery, were inversely associated with each PBR. Similarly, the ratios of antibiotic concentration in saliva to rat plasma were almost constant for each antibiotic, revealing an inverse relationship with PBRs. CONCLUSION: These results appear to indicate that low molecular weight antibiotics are excreted into saliva through passive diffusion, inversely relating to their PBRs, and that high concentrations of antibiotics in the saliva have the potential to change the oral ecological environment.


Assuntos
Ceftizoxima/análogos & derivados , Cefalosporinas/sangue , Cefalosporinas/farmacocinética , Adulto , Animais , Área Sob a Curva , Cefotaxima/administração & dosagem , Cefotaxima/sangue , Cefotaxima/farmacocinética , Ceftizoxima/administração & dosagem , Ceftizoxima/sangue , Ceftizoxima/farmacocinética , Cefalosporinas/administração & dosagem , Cromatografia Líquida de Alta Pressão , Difusão , Feminino , Humanos , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Cinética , Masculino , Perfusão , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Saliva/metabolismo , Estatísticas não Paramétricas , Cefozopran
11.
J Oral Pathol Med ; 32(10): 586-94, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14632933

RESUMO

BACKGROUND: Antimicrobial peptides in saliva appear to play a crucial role in the regulation of oral Candida growth, and study on antimicrobial excretion in saliva and oral candidiasis appears useful for the analysis of pathophysiology of oral candidiasis. METHODS: To clarify the role of saliva in the regulation of oral Candida growth, the levels of antimicrobial proteins and peptides and their excretion rates were examined in saliva obtained from 50 patients with oral candidiasis and 35 healthy individuals. RESULTS: The inhibitory activities of patients' saliva against Candida adhesion with HeLa cells and against Candida growth (radiolabeled glucose incorporation) were lower than those of saliva from the healthy controls. The salivary levels of lactoferrin (Lf; 11 +/- 9 microg/ml), secretory immunoglobulin A (sIgA; 160 +/- 37 microg/ml), beta-defensin 1 (375 +/- 37 ng/ml), and beta-defensin 2 (412 +/- 51 ng/ml) in the patients were largely lower than those in the control group (33 +/- 14 microg/ml, 204 +/- 51 microg/ml, 452 +/- 89 ng/ml, and 530 +/- 142 ng/ml, respectively), although the transferrin (Tf) and secretory component (SC) levels were almost same in both groups, and alpha-defensin 1 was slightly increased in the patient group (660 +/- 115 ng/ml vs. 467 +/- 168 ng/ml). In addition, the excretion rates of the proteins and peptides were largely decreased in the patients (Tf: 14 +/- 2 microg/10 min vs. 34 +/- 7 microg/10 min; Lf: 18 +/- 11 microg/10 min vs. 139 +/- 43 microg/10 min; sIgA: 300 +/- 132 microg/10 min vs. 900 +/- 207 microg/10 min; SC: 112 +/- 46 microg/10 min vs. 292 +/- 64 microg/10 min; alpha-defensin 1: 1223 +/- 431 ng/10 min vs. 2044 +/- 612 ng/10 min; beta-defensin 1: 687 +/- 243 ng/10 min vs. 1985 +/- 295 ng/10 min; and beta-defensin 2: 784 +/- 299 ng/10 min vs. 2288 +/- 278 ng/10 min). CONCLUSION: These results conclusively suggest that oral candidiasis is associated with salivary gland hypofunction and that decreases of salivary antibacterial proteins induce Candida overgrowth.


Assuntos
Anti-Infecciosos/análise , Candidíase Bucal/metabolismo , Saliva/química , Proteínas e Peptídeos Salivares/análise , Idoso , Anfotericina B/análise , Anfotericina B/uso terapêutico , Antifúngicos/análise , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase Bucal/tratamento farmacológico , Estudos de Casos e Controles , Feminino , Células HeLa/efeitos dos fármacos , Células HeLa/microbiologia , Humanos , Imunoglobulina A Secretora/análise , Lactoferrina/análise , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Componente Secretório/análise , Taxa Secretória , Transferrina/análise , beta-Defensinas/análise
12.
Clin Diagn Lab Immunol ; 11(6): 1111-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15539515

RESUMO

To establish a novel strategy for the control of fungal infection, we examined the antifungal and neutrophil-activating activities of antimicrobial peptides. The duration of survival of 50% of mice injected with a lethal dose of Candida albicans (5 x 10(8) cells) or Aspergillus fumigatus (1 x 10(8) cells) was prolonged 3 to 5 days by the injection of 10 microg of peptide 2 (a lactoferrin peptide) and 10 microg of alpha-defensin 1 for five consecutive days and was prolonged 5 to 13 days by the injection of 0.1 microg of granulocyte-monocyte colony-stimulating factor (GM-CSF) and 0.5 microg of amphotericin B. When mice received a combined injection of peptide 2 (10 microg/day) with amphotericin B (0.5 microg/day) for 5 days after the lethal fungal inoculation, their survival was greatly prolonged and some mice continued to live for more than 5 weeks, although the effective doses of peptide 2 for 50 and 100% suppression of Candida or Aspergillus colony formation were about one-third and one-half those of amphotericin B, respectively. In vitro, peptide 2 as well as GM-CSF increased the Candida and Aspergillus killing activities of neutrophils, but peptides such as alpha-defensin 1, beta-defensin 2, and histatin 5 did not upregulate the killing activity. GM-CSF together with peptide 2 but not other peptides enhanced the production of superoxide (O2-) by neutrophils. The upregulation by peptide 2 was confirmed by the activation of the O2- -generating pathway, i.e., activation of large-molecule guanine binding protein, phosphatidyl-inositol 3-kinase, protein kinase C, and p47phox as well as p67phox. In conclusion, different from natural antimicrobial peptides, peptide 2 has a potent neutrophil-activating effect which could be advantageous for its clinical use in combination with antifungal drugs.


Assuntos
Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Candida albicans , Lactoferrina/administração & dosagem , Peptídeos/administração & dosagem , Animais , Aspergilose/metabolismo , Aspergilose/patologia , Candidíase/patologia , Células Cultivadas , Feminino , Camundongos , Ativação de Neutrófilo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , alfa-Defensinas/administração & dosagem
13.
Oncology ; 64(4): 407-15, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12759539

RESUMO

OBJECTIVES: Cytokines produced by tumor cells and tumor-infiltrating lymphocytes (TIL) appear to regulate tumor cell growth and the cytotoxic activity of TIL. The objectives of the present study were to investigate cytokine generation patterns in tumor cells and TIL and to examine the influence of cancer therapy on this cytokine production and the cytotoxic activity of TIL. METHODS: We determined the levels of cytokines produced by tumor cells and TIL in vitro and measured the cytotoxic activity of TIL against Daudi cells in patients with oral squamous cell carcinoma (OSC) before and 1 week after the start of concomitant chemo-radio-immunotherapy. RESULTS: Before the therapy, OSC cells generated higher levels of granulocyte-macrophage colony-stimulating factor, tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) than did oral keratinocytes isolated from the noninflamed gingivae of healthy individuals, but both kinds of cells generated similar levels of interleukin (IL)-1beta and IL-6. Compared with peripheral blood mononuclear cells (PBMC) of the patients, TIL produced higher levels of IL-1beta, IL-6, IL-10, TNF-alpha and TGF-beta, whereas their production of IL-12 and interferon-gamma (IFN-gamma) was only slightly higher than that in PBMC. After 1 week of therapy, the cytokine production by OSC cells had largely decreased, while the production of TNF-alpha, IFN-gamma, TGF-beta and IL-12 by TIL had increased greatly, although other cytokine levels were almost constant during the investigations. The cytotoxic activity of TIL was higher than that of PBMC before the therapy, and this activity was strongly increased by 1 week of therapy. CONCLUSIONS: These results suggest that the cytokine productivities of TIL and tumor cells differ from those of PBMC and normal keratinocytes, respectively, and that chemo-radio-immunotherapy modulates in situ cytokine generation, which is advantageous for inhibition of tumor cell growth and activation of TIL.


Assuntos
Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/terapia , Citocinas/biossíntese , Imunoterapia Adotiva , Linfócitos/metabolismo , Neoplasias Bucais/imunologia , Neoplasias Bucais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Quimioterapia Adjuvante , Citocinas/genética , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Humanos , Imunoterapia Adotiva/métodos , Interferon gama/biossíntese , Interleucina-1/biossíntese , Interleucina-10/biossíntese , Interleucina-12/biossíntese , Interleucina-6/biossíntese , Células Matadoras Ativadas por Linfocina , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/radioterapia , Radioterapia Adjuvante , Fator de Crescimento Transformador beta/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
14.
Cancer Sci ; 95(8): 644-50, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15298726

RESUMO

We examined the influence of ROS on the phosphorylation and complex formation of Bcl-2 family proteins in Mn-superoxide dismutase (SOD) antisense-transfected squamous cell carcinoma cells, OSC-4 cells. The increase of intracellular ROS level induced by cis-diamminedichloroplatinum (CDDP) and gamma-ray treatment was greater in antisense-transfected cells than in control vector-transfected cells, and apoptosis was more extensively induced in the former. Antisense-transfected cells expressed high levels of Bax and Bak, but low levels of Bcl-2 and Bcl-XL when treated with CDDP, peplomycin, 5-fluorouracil or gamma-rays. After treatment with these agents, the phosphorylation of protein kinase A, Bcl-2 (Thr56) and Bad (Ser155) was increased, especially in antioxidant (N-acetylcysteine and pyrrolidine dithiocarbamate)-pretreated control cells, but the phosphorylation levels were very low in the antisense-transfected cells. Bcl-2 ubiquitination was increased, but ubiquitination of Bad and Bax was decreased in the antisense-transfected cells, although their ubiquitination was increased by the antioxidants. These results reveal that ROS induce apoptosis by regulating the phosphorylation and ubiquitination of Bcl-2 family proteins, resulting in increased proapoptotic protein levels and decreased antiapoptotic protein expression.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Células Tumorais Cultivadas/patologia , Antineoplásicos/toxicidade , Cisplatino/toxicidade , Humanos , Fosforilação , Transfecção , Ubiquitinas/metabolismo
15.
J Pharmacol Exp Ther ; 307(1): 230-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12954803

RESUMO

Green tea polyphenols (GTPPs) are considered beneficial to human health, especially as chemopreventive agents. Recently, cytotoxic reactive oxygen species (ROS) were identified in tumor and certain normal cell cultures incubated with high concentrations of the most abundant GTPP, (-)-epigallocatechin-3-gallate (EGCG). If EGCG also provokes the production of ROS in normal epithelial cells, it may preclude the topical use of EGCG at higher doses. The current study examined the oxidative status of normal epithelial, normal salivary gland, and oral carcinoma cells treated with EGCG, using ROS measurement and catalase and superoxide dismutase activity assays. The results demonstrated that high concentrations of EGCG induced oxidative stress only in tumor cells. In contrast, EGCG reduced ROS in normal cells to background levels. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and 5-bromodeoxyuridine incorporation data were also compared between the two oral carcinoma cell lines treated by EGCG, which suggest that a difference in the levels of endogenous catalase activity may play an important role in reducing oxidative stress provoked by EGCG in tumor cells. It is concluded that pathways activated by GTPPs or EGCG in normal epithelial versus tumor cells create different oxidative environments, favoring either normal cell survival or tumor cell destruction. This finding may lead to applications of naturally occurring polyphenols to enhance the effectiveness of chemo/radiation therapy to promote cancer cell death while protecting normal cells.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Células Epiteliais/efeitos dos fármacos , Flavonoides , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Chá/química , Bromodesoxiuridina/metabolismo , Catalase/metabolismo , Células Epiteliais/metabolismo , Humanos , Neoplasias , Fenóis/farmacologia , Polímeros/farmacologia , Superóxido Dismutase/metabolismo , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Células Tumorais Cultivadas
16.
J Pharmacol Exp Ther ; 308(1): 317-23, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14569057

RESUMO

The green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) possesses promising anticancer potential. Although in vivo studies unveiled the metabolic routes and pharmacokinetics of EGCG and showed no adverse effects, in vitro studies at high concentrations demonstrated oxidative stress. EGCG causes differential oxidative environments in tumor versus normal epithelial cells, but the roles that EGCG, hydrogen peroxide (H2O2), and intracellular catalase play in the epithelial system are largely unknown. The current study employed enzyme activity assays, reactive oxygen species quantification, and immunoblotting to investigate whether EGCG-induced differential effects correlate with levels of key antioxidant enzymes and H2O2. It was found that normal human keratinocytes with high catalase activity are least susceptible to H2O2, whereas H2O2 caused significant cytotoxicity in oral carcinoma cell lines. However, the EGCG-induced differential effects could not be duplicated by H2O2 alone. The addition of exogenous catalase failed to completely prevent the EGCG-induced cytotoxicity and rescue the EGCG-induced growth arrest in the tumor cells. The antioxidant N-acetyl-L-cysteine rescued the tumor cells from H2O2-induced damage only, but not from EGCG-induced mitochondrial damage. Finally, alterations in catalase or superoxide dismutase activities were not observed upon EGCG exposure. In conclusion, although endogenous catalase may play a role in response to H2O2-induced cytotoxicity, the EGCG-induced cytotoxic effects on tumor cells mainly result from sources other than H2O2.


Assuntos
Catalase/metabolismo , Catequina/análogos & derivados , Catequina/farmacologia , Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/farmacologia , Chá/química , Acetilcisteína/farmacologia , Caspase 3 , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimioprevenção , Combinação de Medicamentos , Ativação Enzimática , Flavonoides , Humanos , Fenóis , Polifenóis , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Células Tumorais Cultivadas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA