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1.
Rom J Morphol Embryol ; 58(4): 1175-1184, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29556606

RESUMO

Targeting epidermal growth factor receptor (EGFR) in patients with non-small-cell lung cancer (NSCLC) having EGFR mutations is associated with an improved overall survival. The aim of this study is to verify, if EGFR mutations detected by immunohistochemistry (IHC) is a convincing way to preselect patients for DNA-sequencing and to figure out, the statistical association between EGFR mutation, wild-type EGFR overexpression, gene copy number gain, which are the main factors inducing EGFR tumorigenic activity and the clinicopathological data. Two hundred sixteen tumor tissue samples of primarily chemotherapeutic naïve NSCLC patients were analyzed for EGFR mutations E746-A750del and L858R and correlated with DNA-sequencing. Two hundred six of which were assessed by IHC, using 6B6 and 43B2 specific antibodies followed by DNA-sequencing of positive cases and 10 already genotyped tumor tissues were also included to investigate debugging accuracy of IHC. In addition, EGFR wild-type overexpression was IHC evaluated and EGFR gene copy number determination was performed by fluorescence in situ hybridization (FISH). Forty-one÷206 (19.9%) cases were positive for mutated EGFR by IHC. Eight of them had EGFR mutations of exons 18-21 by DNA-sequencing. Hit rate of 10 already genotyped NSCLC mutated cases was 90% by IHC. Positive association was found between EGFR mutations determined by IHC and both EGFR overexpression and increased gene copy number (p=0.002 and p<0.001, respectively). Additionally, positive association was detected between EGFR mutations, high tumor grade and clinical stage (p<0.001). IHC staining with mutation specific antibodies was demonstrated as a possible useful screening test to preselect patients for DNA-sequencing.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Dosagem de Genes , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mutação , Estudos Retrospectivos , Análise de Sequência de DNA
2.
PLoS One ; 11(12): e0168801, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28033349

RESUMO

Detection of cancer at an early stage is pivotal for successful treatment and long term survival, yet early diagnosis requires sensitive and specific markers that can be easily detected by screening procedures. Differences in the surface structure of tumor and healthy cells, if sufficiently pronounced and discernible, may serve that purpose. We analyzed the luminal surface of healthy and neoplastic human colorectal tissues for the presence and architecture of the glycocalyx-a dense network of highly glycosylated proteins-using transmission electron microscopy. The ultrastructural analyses showed that 93% of healthy mucosae were covered by an intact glycocalyx. Contrarily, on over 90% of the surface of neoplastic cells the glycocalyx was absent. The sensitivity and specificity of our marker "absence of a glycocalyx" are excellent, being 91% (83-96%) and 96% (89-99%) for adenocarcinomas and 94% (73-100%) and 92% (85-97%) for precancerous polyps (means and 95% confidence intervals). Using a cell culture model we could demonstrate that a particulate probe targeting a cell surface receptor usually concealed beneath the glycocalyx can bind selectively to glycocalyx-free areas of a tumor cell layer. We propose that the absence of a glycocalyx may serve as novel type of tumor marker. If the absence of the glycocalyx can be detected e.g. via binding of imaging probes to non-shielded surface receptors of anomalously differentiated cells, this tumor marker could be used to enable early diagnosis of colorectal cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Detecção Precoce de Câncer , Glicocálix/metabolismo , Mucosa Intestinal/metabolismo , Idoso , Idoso de 80 Anos ou mais , Células CACO-2 , Neoplasias Colorretais/patologia , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Receptores de Superfície Celular/metabolismo
3.
Diagn Pathol ; 11(1): 59, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-27388913

RESUMO

BACKGROUND: Due to therapeutic implications with regard to both efficiency and safety of chemotherapy agents it is important to differentiate between subtypes of NSCLC. Up to today we experience a continuous reservation regarding the use of fine needle aspiration cytology. The aim of the present study is to estimate the value of cytologic criteria for lung cancer typing on small biopsies independent from all possible technique failures. METHODS: Between January 1997 and December 2008 760 intraoperative FNAC- (fine needle aspiration cytology) specimens from 702 patients have been examined. Cytologic evaluation and immediate communication of results to the surgeons followed. Afterwards, intraoperative cytologic findings were compared with final histologic diagnoses of the resected specimens. RESULTS: Intraoperative cytologic analysis yielded a sensitivity of 94.8 %, a specificity of 98.8 %. An overall positive predictive value of 99.8 % with respect to final histologic analysis of primary lung cancer was achieved. The highest value could be reached for adenocarcinomas, followed by carcinoids and squamous cell carcinomas. CONCLUSIONS: Lung cancer typing according to cytologic criteria is feasible and accurate as well as comparable with results of histologic analysis on small specimens. Herewith, clinicians can come up to the increasing demands on minimally invasive harvested specimens with regard to therapeutic implications.


Assuntos
Adenocarcinoma/diagnóstico , Tumor Carcinoide/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma/classificação , Idoso , Biópsia por Agulha Fina , Tumor Carcinoide/classificação , Carcinoma Pulmonar de Células não Pequenas/classificação , Carcinoma de Células Escamosas/classificação , Citodiagnóstico , Feminino , Humanos , Período Intraoperatório , Pulmão/patologia , Neoplasias Pulmonares/classificação , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
4.
Cancer Res ; 76(13): 3785-801, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27197161

RESUMO

Non-small cell lung cancer (NSCLC) is characterized by early metastasis and has the highest mortality rate among all solid tumors, with the majority of patients diagnosed at an advanced stage where curative therapeutic options are lacking. In this study, we identify a targetable mechanism involving TGFß elevation that orchestrates tumor progression in this disease. Substantial activation of this pathway was detected in human lung cancer tissues with concomitant downregulation of BAMBI, a negative regulator of the TGFß signaling pathway. Alterations of epithelial-to-mesenchymal transition (EMT) marker expression were observed in lung cancer samples compared with tumor-free tissues. Distinct alterations in the DNA methylation of the gene regions encoding TGFß pathway components were detected in NSCLC samples compared with tumor-free lung tissues. In particular, epigenetic silencing of BAMBI was identified as a hallmark of NSCLC. Reconstitution of BAMBI expression in NSCLC cells resulted in a marked reduction of TGFß-induced EMT, migration, and invasion in vitro, along with reduced tumor burden and tumor growth in vivo In conclusion, our results demonstrate how BAMBI downregulation drives the invasiveness of NSCLC, highlighting TGFß signaling as a candidate therapeutic target in this setting. Cancer Res; 76(13); 3785-801. ©2016 AACR.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Pulmonares/patologia , Proteínas de Membrana/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Idoso , Animais , Apoptose , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Metilação de DNA , Regulação para Baixo , Epigênese Genética , Transição Epitelial-Mesenquimal , Feminino , Imunofluorescência , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
BMC Pulm Med ; 16: 19, 2016 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-26803467

RESUMO

BACKGROUND: Mycobacterial infections remain a significant cause of morbidity and mortality worldwide. Due to limitations of the currently available model systems, there are still comparably large gaps in the knowledge about the pathogenesis of these chronic inflammatory diseases in particular with regard to the human host. Therefore, we aimed to characterize the initial phase of mycobacterial infections utilizing a human ex vivo lung tissue culture model designated STST (Short-Term Stimulation of Tissues). METHODS: Human lung tissues from 65 donors with a size of 0.5-1 cm(3) were infected each with two strains of three different mycobacterial species (M. tuberculosis, M. avium, and M. abscessus), respectively. In order to preserve both morphology and nucleic acids, the HOPE® fixation technique was used. The infected tissues were analyzed using histo- and molecular-pathological methods. Immunohistochemistry was applied to identify the infected cell types. RESULTS: Morphologic comparisons between ex vivo incubated and non-incubated lung specimens revealed no noticeable differences. Viability of ex vivo stimulated tissues demonstrated by TUNEL-assay was acceptable. Serial sections verified sufficient diffusion of the infectious agents deep into the tissues. Infection was confirmed by Ziel Neelsen-staining and PCR to detect mycobacterial DNA. We observed the infection of different cell types, including macrophages, neutrophils, monocytes, and pneumocytes-II, which were critically dependent on the mycobacterial species used. Furthermore, different forms of nuclear alterations (karyopyknosis, karyorrhexis, karyolysis) resulting in cell death were detected in the infected cells, again with characteristic species-dependent differences. CONCLUSION: We show the application of a human ex vivo tissue culture model for mycobacterial infections. The immediate primary infection of a set of different cell types and the characteristic morphologic changes observed in these infected human tissues significantly adds to the current understanding of the initial phase of human pulmonary tuberculosis. Further studies are ongoing to elucidate the molecular mechanisms involved in the early onset of mycobacterial infections in the human lung.


Assuntos
Pulmão/patologia , Infecções por Mycobacterium não Tuberculosas/patologia , Tuberculose Pulmonar/patologia , Células Epiteliais Alveolares/microbiologia , Células Epiteliais Alveolares/patologia , Núcleo Celular/patologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Técnicas In Vitro , Pulmão/metabolismo , Linfócitos/microbiologia , Linfócitos/patologia , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/patologia , Monócitos/microbiologia , Monócitos/patologia , Mycobacterium/genética , Infecções por Mycobacterium não Tuberculosas/metabolismo , Mycobacterium avium/genética , Mycobacterium tuberculosis/genética , Neutrófilos/microbiologia , Neutrófilos/patologia , Reação em Cadeia da Polimerase , Técnicas de Cultura de Tecidos , Sobrevivência de Tecidos , Tuberculose Pulmonar/metabolismo
6.
Diagn Pathol ; 9: 165, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25227424

RESUMO

BACKGROUND: Epidermal Growth Factor Receptor (EGFR) targeting therapies are currently of great relevance for the treatment of lung cancer. For this reason, in addition to mutational analysis immunohistochemistry (IHC) of EGFR in lung cancer has been discussed for the decision making of according therapeutic strategies. The aim of this study was to obtain standardization of EGFR-expression methods for the selection of patients who might benefit of EGFR targeting therapies. METHODS: As a starting point of a broad investigation, aimed at elucidating the expression of EGFR on different biological levels, four EGFR specific antibodies were analyzed concerning potential differences in expression levels by Immunohistochemistry (IHC) and correlated with fluorescence in situ hybridization (FISH) analysis and clinicopathological data. 206 tumor tissues were analyzed in a tissue microarray format employing immunohistochemistry with four different antibodies including Dako PharmDx kit (clone 2-18C9), clone 31G7, clone 2.1E1 and clone SP84 using three different scoring methods. Protein expression was compared to FISH utilizing two different probes. RESULTS: EGFR protein expression determined by IHC with Dako PharmDx kit, clone 31G7 and clone 2.1E1 (p ≤ 0.05) correlated significantly with both FISH probes independently of the three scoring methods; best correlation is shown for 31G7 using the scoring method that defined EGFR positivity when ≥ 10% of the tumor cells show membranous staining of moderate and severe intensity (p=0.001). CONCLUSION: Overall, our data show differences in EGFR expression determined by IHC, due to the applied antibody. Highest concordance with FISH is shown for antibody clone 31G7, evaluated with score B (p=0.001). On this account, this antibody clone might by utilized for standard evaluation of EGFR expression by IHC. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_165.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Dosagem de Genes/genética , Regulação Neoplásica da Expressão Gênica/genética , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Neoplasias Pulmonares/patologia , Idoso , Anticorpos/imunologia , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/genética , Tumor Carcinoide/patologia , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/genética , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Grandes/diagnóstico , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , DNA de Neoplasias/genética , Diagnóstico Diferencial , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Feminino , Humanos , Imuno-Histoquímica/normas , Hibridização in Situ Fluorescente/normas , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reprodutibilidade dos Testes
7.
Lab Invest ; 94(8): 927-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24933424

RESUMO

Alterations in the DNA methylome are characteristic for numerous diseases and a typical hallmark of cancer. Therefore, DNA methylation is currently under investigation in research labs and has also entered diagnostics. Recently, protocols like the BeadChip technology have become commercially available to study DNA methylation in an array format and semiquantitative fashion. However, it is known that fixation of the sample material with formalin prior to BeadChip analysis can affect the results. In this study we compared the influence of fixation on the outcome of BeadChip analysis. From six patients each a lung cancer tissue sample and a corresponding tumor-free lung tissue sample were collected. The samples were separated into three pieces. One piece of each sample was fixed with formalin, another one by the non-cross-linking HOPE technique (Hepes-glutamic acid buffer mediated Organic solvent Protection Effect). Subsequently, both became paraffin embedded. As a reference, the remaining third piece was cryopreserved. In addition we used three adenocarcinoma cell lines (H838, A549, and H1650) to validate the results from patient tissues. We show that using the HOPE technique instead of formalin largely prevents the introduction of formalin-fixation related artifacts. An ANOVA analysis significantly separated HOPE- and cryopreserved from formalin-fixed samples (FDR<0.05), while differences in the methylation data obtained from HOPE-fixed and cryopreserved material were minor. Consequently, HOPE fixation is superior to formalin fixation if a subsequent BeadChip analysis of paraffin-embedded sample material is intended.


Assuntos
Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/metabolismo , Metilação de DNA , DNA de Neoplasias/metabolismo , Neoplasias Pulmonares/metabolismo , Pulmão/metabolismo , Preservação de Tecido , Adenocarcinoma/patologia , Idoso , Artefatos , Soluções Tampão , Carcinoma Adenoescamoso/metabolismo , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/prevenção & controle , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Criopreservação , DNA de Neoplasias/isolamento & purificação , Feminino , Ácido Glutâmico/química , HEPES/química , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise Serial de Tecidos , Fixação de Tecidos
10.
Respir Med ; 107(4): 587-95, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23312618

RESUMO

Induced sputum is a non-invasive sampling technique for the analysis of airway inflammation in various lung diseases and comprises valuable potential for the identification of biomarkers and therapeutic targets by molecular methods. In the context of biobanking with preservation of induced sputum samples for subsequent analyses we applied the HEPES-glutamic acid buffer-mediated organic solvent protection effect (HOPE)-technique for preparation of induced sputum samples. Induced sputum samples of 20 patients with moderate to severe chronic obstructive pulmonary disease (COPD) and 12 healthy controls were collected. Cell pellets of induced sputum samples were preserved with HOPE and subsequently embedded in paraffin. Immunostaining of paraffin-block sections for interleukin-8, interleukin-17, myeloperoxidase, matrixmetalloproteinase-9, CD68, and CD8 revealed distinct signals without antigen retrieval. Moreover, RNA was extracted and successfully used for transcription microarray analysis. Sputum samples preserved by the HOPE-technique display a tool to address scientific approaches in pulmonary research, which can enable the identification of new biomarkers and therapeutic targets in respiratory diseases.


Assuntos
Bancos de Espécimes Biológicos , Doença Pulmonar Obstrutiva Crônica/patologia , Escarro/citologia , Fixação de Tecidos/métodos , Idoso , Biomarcadores/metabolismo , Contagem de Células , Feminino , Volume Expiratório Forçado/fisiologia , Perfilação da Expressão Gênica/métodos , HEPES , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Inclusão em Parafina/métodos , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/metabolismo , Fumar/fisiopatologia , Escarro/metabolismo
11.
Cancer Immunol Immunother ; 62(2): 309-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22923191

RESUMO

Lung cancer is frequently complicated by pulmonary infections which may impair prognosis of this disease. Therefore, we investigated the effect of bacterial lipopolysaccharides (LPS) on tumor proliferation in vitro in the non-small cell lung cancer (NSCLC) cell line A549, ex vivo in a tissue culture model using human NSCLC specimens and in vivo in the A549 adenocarcinoma mouse model. LPS induced a time- and dose-dependent increase in proliferation of A549 cells as quantified by MTS activity and cell counting. In parallel, an increased expression of the proliferation marker Ki-67 and cyclooxygenase (COX)-2 was detected both in A549 cells and in ex vivo human NSCLC tissue. Large amounts of COX-2-derived prostaglandin (PG)E(2) were secreted from LPS-stimulated A549 cells. Pharmacological interventions revealed that the proliferative effect of LPS was dependent on CD14 and Toll-like receptor (TLR)4. Moreover, blocking of the epidermal growth factor receptor (EGFR) also decreased LPS-induced proliferation of A549 cells. Inhibition of COX-2 activity in A549 cells severely attenuated both PGE(2) release and proliferation in response to LPS. Synthesis of PGE(2) was also reduced by inhibiting CD14, TLR4 and EGFR in A549 cells. The proliferative effect of LPS on A549 cells could be reproduced in the A549 adenocarcinoma mouse model with enhancement of tumor growth and Ki-67 expression in implanted tumors. In summary, LPS induces proliferation of NSCLC cells in vitro, ex vivo in human NSCLC specimen and in vivo in a mouse model of NSCLC. Pulmonary infection may thus directly induce tumor progression in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Receptores ErbB/metabolismo , Lipopolissacarídeos/imunologia , Neoplasias Pulmonares/patologia , Proteínas de Membrana/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/análise , Dinoprostona/metabolismo , Modelos Animais de Doenças , Receptores ErbB/antagonistas & inibidores , Humanos , Indometacina/farmacologia , Antígeno Ki-67/biossíntese , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Nitrobenzenos/farmacologia , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
12.
Virchows Arch ; 461(2): 185-93, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22729141

RESUMO

The International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS), and the European Respiratory Society (ERS) proposed a classification for lung adenocarcinomas (ADC) based on the predominant growth pattern. This classification has been shown to have prognostic and maybe even predictive impact. However, until now, the reproducibility of this classification has not been sufficiently demonstrated. Digital images of 40 selected ADC cases were shown twice to members of the Pulmonary Pathology Working Group of the German Society of Pathology. Each time a teledialogue-based survey on the classification was performed. Between the voting procedures, salient features of the novel classification were presented and discussed in detail by its members. The mean percentages of consensual votes per pattern ranged between 59.6 and 75 %, with lepidic and solid being the pattern with the most discordant and concordant votes, respectively. The other patterns ranged in between (papillary 65.8 %; acinar 67.8 %; micropapillary 74.2 %). The extent of disagreement decreased after the educational session. This decrease, however, was heterogeneous for the different patterns with acinar being the pattern with the strongest improvement. The overall number of abstentions decreased significantly after the educational session (p < 0.001) as well. The IASLC/ATS/ERS classification of lung ADC can be applied with reasonable consensus even for difficult cases in a nationwide context. The reproducibility evidently improves following educational sessions, even among experienced lung pathologists. Worldwide harmonization is clearly the next step on the way to a clinically meaningful, internationally accepted use of this novel prognostic and potentially predictive tool in lung pathology.


Assuntos
Adenocarcinoma/classificação , Educação Médica Continuada , Neoplasias Pulmonares/classificação , Patologia Clínica/normas , Adenocarcinoma/patologia , Congressos como Assunto , Humanos , Neoplasias Pulmonares/patologia , Reprodutibilidade dos Testes
14.
J Biol Chem ; 286(24): 21266-76, 2011 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21515687

RESUMO

To improve the low antimicrobial activity of LF11, an 11-mer peptide derived from human lactoferricin, mutant sequences were designed based on the defined structure of LF11 in the lipidic environment. Thus, deletion of noncharged polar residues and strengthening of the hydrophobic N-terminal part upon adding a bulky hydrophobic amino acid or N-acylation resulted in enhanced antimicrobial activity against Escherichia coli, which correlated with the peptides' degree of perturbation of bacterial membrane mimics. Nonacylated and N-acylated peptides exhibited different effects at a molecular level. Nonacylated peptides induced segregation of peptide-enriched and peptide-poor lipid domains in negatively charged bilayers, although N-acylated peptides formed small heterogeneous domains resulting in a higher degree of packing defects. Additionally, only N-acylated peptides perturbed the lateral packing of neutral lipids and exhibited increased permeability of E. coli lipid vesicles. The latter did not correlate with the extent of improvement of the antimicrobial activity, which could be explained by the fact that elevated binding of N-acylated peptides to lipopolysaccharides of the outer membrane of gram-negative bacteria seems to counteract the elevated membrane permeabilization, reflected in the respective minimal inhibitory concentration for E. coli. The antimicrobial activity of the peptides correlated with an increase of membrane curvature stress and hence bilayer instability. Transmission electron microscopy revealed that only the N-acylated peptides induced tubular protrusions from the outer membrane, whereas all peptides caused detachment of the outer and inner membrane of E. coli bacteria. Viability tests demonstrated that these bacteria were dead before onset of visible cell lysis.


Assuntos
Membrana Celular/metabolismo , Escherichia coli/metabolismo , Lactoferrina/química , Acilação , Peptídeos Catiônicos Antimicrobianos/química , Biofísica/métodos , Varredura Diferencial de Calorimetria/métodos , Hemólise , Humanos , Leucócitos Mononucleares/metabolismo , Lipossomos/química , Microscopia Eletrônica de Transmissão/métodos , Peptídeos/química , Fosfolipídeos/química , Estrutura Terciária de Proteína
15.
Pulm Pharmacol Ther ; 24(2): 232-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21146625

RESUMO

BACKGROUND: Infection with Pseudomonas aeruginosa (PA) induces mucus hypersecretion in airways. Therapeutic options to attenuate excessive mucus expression are sparse. OBJECTIVE: To investigate the effect of steroids and N-acetyl-cysteine (NAC) on PA-induced mucus expression. MATERIAL AND METHODS: Calu-3 cells and explanted human mucosa from the upper airways were stimulated with either PA, lipopolysaccharide from alginate producing PA (smooth, sPA-LPS) or non-alginate producing PA (rough, rPA-LPS). Dexamethasone (DEX) and NAC were added in different concentrations. Expression of mucin (MUC5AC) gene and mucin protein expression was quantified using PAS (periodic acids Schiff) staining and real time PCR. RESULTS: PA, sPA-LPS or rPA-LPS significantly induced mucin protein and MUC5AC gene expression in Calu-3 cells and explanted mucosal tissue (P < 0.05). Both DEX and NAC significantly decreased PA-, sPA-LPS- and rPA-LPS-induced mucin protein expression both in vitro and ex vivo (P < 0.05). A significant reduction was also observed for MUC5AC gene expression with the two agents (P < 0.05) except for sPA-LPS-induced mucin gene expression in vitro (P > 0.05). DISCUSSION AND CONCLUSION: Our data show that both an anti-inflammatory drug (DEX) and an anti-oxidative agent (NAC) can attenuate PA-induced mucus expression in human airways. These results support the use of steroids and NAC in clinical practice to treat PA-induced mucus hypersecretion.


Assuntos
Acetilcisteína/farmacologia , Dexametasona/farmacologia , Muco/metabolismo , Pseudomonas aeruginosa/isolamento & purificação , Acetilcisteína/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Linhagem Celular , Dexametasona/administração & dosagem , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Expectorantes/administração & dosagem , Expectorantes/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mucina-5AC/genética , Muco/microbiologia , Reação em Cadeia da Polimerase , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/microbiologia
16.
Respir Res ; 11: 67, 2010 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-20513241

RESUMO

BACKGROUND: Nontypeable Haemophilus influenzae (NTHI) may play a role as an infectious trigger in the pathogenesis of chronic obstructive pulmonary disease (COPD). Few data are available regarding the influence of acute and persistent infection on tissue remodelling and repair factors such as transforming growth factor (TGF)-beta. METHODS: NTHI infection in lung tissues obtained from COPD patients and controls was studied in vivo and using an in vitro model. Infection experiments were performed with two different clinical isolates. Detection of NTHI was done using in situ hybridization (ISH) in unstimulated and in in vitro infected lung tissue. For characterization of TGF-beta signaling molecules a transcriptome array was performed. Expression of the TGF-pseudoreceptor BMP and Activin Membrane-bound Inhibitor (BAMBI) was analyzed using immunohistochemistry (IHC), ISH and PCR. CXC chemokine ligand (CXCL)-8, tumor necrosis factor (TNF)-alpha and TGF-beta expression were evaluated in lung tissue and cell culture using ELISA. RESULTS: In 38% of COPD patients infection with NTHI was detected in vivo in contrast to 0% of controls (p < 0.05). Transcriptome arrays showed no significant changes of TGF-beta receptors 1 and 2 and Smad-3 expression, whereas a strong expression of BAMBI with upregulation after in vitro infection of COPD lung tissue was demonstrated. BAMBI was expressed ubiquitously on alveolar macrophages (AM) and to a lesser degree on alveolar epithelial cells (AEC). Measurement of cytokine concentrations in lung tissue supernatants revealed a decreased expression of TGF-beta (p < 0.05) in combination with a strong proinflammatory response (p < 0.01). CONCLUSIONS: We show for the first time the expression of the TGF pseudoreceptor BAMBI in the human lung, which is upregulated in response to NTHI infection in COPD lung tissue in vivo and in vitro. The combination of NTHI-mediated induction of proinflammatory cytokines and inhibition of TGF-beta expression may influence inflammation induced tissue remodeling.


Assuntos
Haemophilus influenzae/isolamento & purificação , Pulmão/metabolismo , Pulmão/virologia , Proteínas de Membrana/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/virologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Mediadores da Inflamação/metabolismo , Interleucina-8/metabolismo , Pulmão/imunologia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/imunologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteína Smad3/metabolismo , Técnicas de Cultura de Tecidos , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
BMC Pulm Med ; 10: 20, 2010 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-20403209

RESUMO

BACKGROUND: While lipopolysaccharide (LPS) from Gram-negative bacteria has been shown to augment inflammation in ventilated lungs information on the effect of Gram-positive bacteria is lacking. Therefore the effect of LPS and a lipopetide from Gram-positive bacteria, PAM3, on ventilated lungs were investigated. METHODS: C57/Bl6 mice were mechanically ventilated. Sterile saline (sham) and different concentrations of LPS (1 microg and 5 microg) and PAM3 (50 nM and 200 nM) were applied intratracheally. Lung function parameters and expression of MIP-2 and TNFalpha as well as influx of neutrophils were measured. RESULTS: Mechanical ventilation increased resistance and decreased compliance over time. PAM3 but not LPS significantly increased resistance compared to sham challenge (P < 0.05). Both LPS and PAM3 significantly increased MIP-2 and TNFalpha mRNA expression compared to sham challenge (P < 0.05). The numbers of neutrophils were significantly increased after LPS at a concentration of 5 microg compared to sham (P < 0.05). PAM3 significantly increased the numbers of neutrophils at both concentrations compared to sham (P < 0.05). CONCLUSIONS: These data suggest that PAM3 similar to LPS enhances ventilator-induced inflammation. Moreover, PAM3 but not LPS increases pulmonary resistance in ventilated lungs. Further studies are warranted to define the role of lipopetides in ventilator-associated lung injury.


Assuntos
Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Lipopeptídeos/farmacologia , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Respiração Artificial , Resistência das Vias Respiratórias/efeitos dos fármacos , Resistência das Vias Respiratórias/fisiologia , Animais , Quimiocina CXCL2/metabolismo , Relação Dose-Resposta a Droga , Lipopeptídeos/metabolismo , Lipopolissacarídeos/metabolismo , Pulmão/citologia , Pulmão/fisiologia , Complacência Pulmonar/efeitos dos fármacos , Complacência Pulmonar/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
18.
BMC Pulm Med ; 10: 21, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20409304

RESUMO

BACKGROUND: A large number of studies have investigated the effects of high tidal volume ventilation in mouse models. In contrast data on very short term effects of low tidal volume ventilation are sparse. Therefore we investigated the functional and structural effects of low tidal volume ventilation in mice. METHODS: 38 Male C57/Bl6 mice were ventilated with different tidal volumes (Vt 5, 7, and 10 ml/kg) without or with application of PEEP (2 cm H2O). Four spontaneously breathing animals served as controls. Oxygen saturation and pulse rate were monitored. Lung function was measured every 5 min for at least 30 min. Afterwards lungs were removed and histological sections were stained for measurement of infiltration with polymorphonuclear leukocytes (PMN). Moreover, mRNA expression of macrophage inflammatory protein (MIP)-2 and tumor necrosis factor (TNF)alpha in the lungs was quantified using real time PCR. RESULTS: Oxygen saturation did not change significantly over time of ventilation in all groups (P > 0.05). Pulse rate dropped in all groups without PEEP during mechanical ventilation. In contrast, in the groups with PEEP pulse rate increased over time. These effects were not statistically significant (P > 0.05). Tissue damping (G) and tissue elastance (H) were significantly increased in all groups after 30 min of ventilation (P < 0.05). Only the group with a Vt of 10 ml/kg and PEEP did not show a significant increase in H (P > 0.05). Mechanical ventilation significantly increased infiltration of the lungs with PMN (P < 0.05). Expression of MIP-2 was significantly induced by mechanical ventilation in all groups (P < 0.05). MIP-2 mRNA expression was lowest in the group with a Vt of 10 ml/kg + PEEP. CONCLUSIONS: Our data show that very short term mechanical ventilation with lower tidal volumes than 10 ml/kg did not reduce inflammation additionally. Formation of atelectasis and inadequate oxygenation with very low tidal volumes may be important factors. Application of PEEP attenuated inflammation.


Assuntos
Inflamação/fisiopatologia , Pulmão/fisiopatologia , Respiração com Pressão Positiva , Animais , Quimiocina CXCL2/metabolismo , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Inflamação/metabolismo , Inflamação/patologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Neutrófilos/patologia , RNA Mensageiro/metabolismo , Volume de Ventilação Pulmonar/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
19.
J Histochem Cytochem ; 58(3): 221-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19995946

RESUMO

Proteome analyses provide diagnostic information which can be essential for therapeutic predictions. The application of such techniques for analyzing paraffin-embedded tissue samples is widely hampered by the use of formalin fixation requiring antigen retrieval procedures in molecular pathology. In prior studies, the HEPES-glutamic acid buffer-mediated organic solvent protection effect (HOPE) technique of tissue fixation has been shown to provide a broad array of biochemical investigations with excellent preservation of morphological structures, DNA, RNA, and proteins, thus supporting the multimethod analysis of archived specimens. Here we show that HOPE fixation is also useful in proteomic investigations by allowing two-dimensional electrophoresis (2DE) and mass spectrometry, using lung cancer tissues. Two-dimensional gels of two-protein extraction protocols derived from HOPE-fixed material displayed characteristic spot patterns with high reproducibility. For comparison, 2DE analysis of ethanol-fixed, formalin-fixed, and frozen samples from the same tissues was performed. Western blotting confirmed immunoreactivity of 2DE-separated proteins from HOPE-fixed tissue samples. Additionally, distinct spots were excised from HOPE-derived 2D gels and successfully subjected to peptide mass fingerprinting. In conclusion, paraffin archives containing HOPE-fixed tissues are applicable to a wide spectrum of molecular investigations including common biochemical methods for proteome analyses and therefore represent a unique source for molecular investigations in the rapidly growing field of molecular pathology. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.


Assuntos
Adenocarcinoma/química , Biomarcadores Tumorais/análise , Carcinoma Pulmonar de Células não Pequenas/química , Carcinoma de Células Escamosas/química , Neoplasias Pulmonares/química , Proteoma/análise , Western Blotting , Criopreservação , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Etanol , Fixadores , Formaldeído , Humanos , Concentração de Íons de Hidrogênio , Inclusão em Parafina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fixação de Tecidos/métodos
20.
Diagn Pathol ; 4: 27, 2009 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-19698096

RESUMO

BACKGROUND: As there is no optimal treatment of non small cell lung cancer due to its resistance to common chemotherapeutics, we investigated the effect of human placenta-conditioned medium on tumor tissue. The human placenta constitutes a mixture of maternal and fetal origin and displays a variety of immunomodulatory aspects. METHODS: Freshly resected non small cell lung cancer tissues were incubated with placenta-conditioned medium in a short-term tissue culture model and A549 cells were challenged, respectively. Term placenta was used for producing conditioned medium and HOPE-fixed stimulated tumor tissue was analyzed for expression of caspase-3 and Ki67 via immunohistochemistry. The effects of conditioned medium on squamous cell carcinoma were further compared to physiological concentrations of Carboplat/Gemzar. RESULTS: Conditioned medium caused in 2 of 3 cases elevated expression of caspase-3 and reduced expression of Ki67 in 3 out of 3 cases, while the chemotherapeutic agents caused no comparable expression of caspase-3 or reduction of Ki67. In cell culture up to 50% of karyopyknosis was investigated and even sterile-filtrated medium caused widespread reduction of Ki67 on protein level. CONCLUSION: Human placenta releases substances that mediate apoptosis and reduce proliferation in tumor tissue and cell culture. As even sterile-filtrated medium caused the mentioned effects we hypothesize one or more soluble mediators. The detailed way of promoting apoptosis and nature of these mediators need to be elucidated in further studies.

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