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1.
World J Urol ; 33(10): 1541-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25433505

RESUMO

OBJECTIVES: To evaluate the outcome of patients after nephrectomy and removal of tumour thrombus and to assess the prognostic value of preoperative parameters. PATIENTS AND METHODS: Ninety-eight patients who were surgically treated between 2002 and 2011 were included. Patients' charts were reviewed, and patients with renal cell carcinoma (RCC) and concomitant tumour thrombus in the renal vein (RV) were compared with those with extended inferior vena cava (IVC) thrombus. Wilcoxon rank-sum test, Kaplan-Meier analysis and uni- and multivariate Cox regression analysis were used for statistical evaluation. RESULTS: Follow-up was 36 months (20-122 months), and 5-year disease-specific survival (DSS) and overall survival were 68.4 and 54.1 %, respectively. Patients with extended thrombus (levels 2-4) had higher intraoperative transfusion rates of concentrated red cells (CRC) and fresh-frozen plasma (FFP) compared with patients with thrombus confined to the RV (CRC: 5.8 vs. 1.5, p < 0.0001; FFP: 2.3 vs. 0.4, p = 0.0032). Surgery time (190 vs. 107 min, p < 0.0001), duration of hospitalisation (16 vs. 11 days, p = 0.0269), serum phosphate (3.64 vs. 3.29 mmol/l, p = 0.0369) and CRP levels (6.7 vs. 4.4 mg/dl, p = 0.0194) as well as aPTT were increased (33.7 vs. 29.6 s, p = 0.0059) in extended thrombus disease. In multivariate analysis, the presence of distant metastasis (p = 0.03) and lymphovascular invasion (p = 0.001), high platelet counts (p = 0.001) and high serum potassium levels (p = 0.032) proved to be independent prognostic factors. CONCLUSION: The surgical treatment of RCC with tumour thrombus in the RV or IVC has favourable results. Extended thrombus disease requires multidisciplinary approach. High serum potassium levels and platelet counts are associated with reduced DSS.


Assuntos
Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Células Neoplásicas Circulantes , Nefrectomia , Veia Cava Inferior , Trombose Venosa/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Prognóstico , Taxa de Sobrevida/tendências , Fatores de Tempo , Trombose Venosa/etiologia , Trombose Venosa/mortalidade , Adulto Jovem
2.
Acta Radiol ; 56(8): 1009-15, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25168023

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI) is routinely used in magnetic resonance imaging (MRI) of prostate cancer. However, the routine use of b values higher than 1000 s/mm(2) is not clear up to present. Moreover, the complex diffusion behavior of malignant and benign prostate tissues hampers precise predictions of contrast in DWI images and apparent diffusion coefficient (ADC) maps. PURPOSE: To quantitatively analyze DWI with different b values in prostate cancer and to identify b values best suitable for cancer detection. MATERIAL AND METHODS: Forty-one patients with histologically proven prostate cancer were examined with high resolution T2-weighted imaging and DWI at 3 Tesla. Five different b values (0, 800, 1000, 1500, 2000 s/mm(2)) were applied. ADC values of tumors and reference areas were measured on ADC maps derived from different pairs of b values. Furthermore, signal intensities of DW images of tumors and reference areas were measured. For analysis, contrast ratios of ADC values and signal intensities of DW images were calculated and compared. RESULTS: No significant differences were found between contrast ratios measured on ADC maps of all analyzed b value pairs (P = 0.43). Contrast ratios calculated from signal intensities of DW images were highest at b values of 1500 and 2000 s/mm(2) and differed significantly from contrast ratios at b values of 800 and 1000 s/mm(2) (P < 0.01). CONCLUSION: Whereas contrast in ADC maps does not significantly change with different b values, contrast ratios of DW images are significantly higher at b-values of 1500 and 2000 s/mm(2) in comparison to b values of 800 and 1000 s/mm(2). Therefore, diagnostic performance of DWI in prostate cancer might be increased by application of b values higher than 1000 s/mm(2).


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias da Próstata/patologia , Idoso , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Nat Med ; 13(2): 164-70, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17259995

RESUMO

Wilson disease is caused by accumulation of Cu(2+) in cells, which results in liver cirrhosis and, occasionally, anemia. Here, we show that Cu(2+) triggers hepatocyte apoptosis through activation of acid sphingomyelinase (Asm) and release of ceramide. Genetic deficiency or pharmacological inhibition of Asm prevented Cu(2+)-induced hepatocyte apoptosis and protected rats, genetically prone to develop Wilson disease, from acute hepatocyte death, liver failure and early death. Cu(2+) induced the secretion of activated Asm from leukocytes, leading to ceramide release in and phosphatidylserine exposure on erythrocytes, events also prevented by inhibition of Asm. Phosphatidylserine exposure resulted in immediate clearance of affected erythrocytes from the blood in mice. Accordingly, individuals with Wilson disease showed elevated plasma levels of Asm, and displayed a constitutive increase of ceramide- and phosphatidylserine-positive erythrocytes. Our data suggest a previously unidentified mechanism for liver cirrhosis and anemia in Wilson disease.


Assuntos
Adenosina Trifosfatases/metabolismo , Anemia/metabolismo , Apoptose/efeitos dos fármacos , Proteínas de Transporte de Cátions/metabolismo , Ceramidas/metabolismo , Cobre/toxicidade , Degeneração Hepatolenticular/metabolismo , Cirrose Hepática/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Adulto , Anemia/etiologia , Animais , ATPases Transportadoras de Cobre , Eritrócitos/metabolismo , Citometria de Fluxo , Hepatócitos/efeitos dos fármacos , Degeneração Hepatolenticular/complicações , Humanos , Marcação In Situ das Extremidades Cortadas , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Fosfatidilserinas/metabolismo , Ratos , Esfingomielina Fosfodiesterase/sangue
4.
World J Urol ; 31(2): 417-21, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23160759

RESUMO

PURPOSE: In male patients, the pudendal block was applied only in rare cases as a therapy of neuralgia of the pudendal nerve. We compared pudendal nerve block (NPB) and combined spinal-epidural anesthesia (CSE) in order to perform a pain-free high-dose-rate (HDR) brachytherapy in a former pilot study in 2010. Regarding this background, in the present study, we only performed the bilateral perineal infiltration of the pudendal nerve. METHODS: In 25 patients (71.8 ± 4.18 years) suffering from a high-risk prostate carcinoma, we performed the HDR-brachytherapy with the NPB. The perioperative compatibility, the subjective feeling (German school marks principle 1-6), subjective pain (VAS 1-10) and the early postoperative course (mobility, complications) were examined. RESULTS: All patients preferred the NPB. There was no change of anesthesia form necessary. The expense time of NPB was 10.68 ± 2.34 min. The hollow needles (mean 24, range 13-27) for the HDR-brachytherapy remained on average 79.92 ± 12.41 min. During and postoperative, pain feeling was between 1.4 ± 1.08 and 1.08 ± 1.00. A transurethral 22 French Foley catheter was left in place for 6 h. All patients felt the bladder catheter as annoying, but they considered postoperative mobility as more important as complete lack of pain. The subjective feeling was described as 2.28 ± 0.74. Any side effects or complications did not appear. CONCLUSIONS: Bilateral NPB is a safe and effective analgesic option in HDR-brachytherapy and can replace CSE. It offers the advantage of almost no impaired mobility of the patient and can be performed by the urologist himself. Using transrectal ultrasound guidance, the method can be learned quickly.


Assuntos
Anestesia por Condução/métodos , Braquiterapia/métodos , Carcinoma/radioterapia , Neoplasias da Próstata/radioterapia , Nervo Pudendo , Idoso , Anestesia Epidural , Raquianestesia , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso , Medição da Dor , Dor Pós-Operatória/prevenção & controle
5.
World J Urol ; 30(3): 399-404, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21874511

RESUMO

PURPOSE: The aim of this study was the analysis of the feasibility and complication rate of central venous port implantation with the surgical cut-down technique applying an intravasal electrographic control of the catheter tip position performed by urologists. PATIENTS AND METHODS: In the time from December 1999 to November 2010, implantation of 324 subcutaneously implanted venous port systems (NuPort-System) has been performed in 316 patients, 221 men (mean age 59.5 years, range 11-87 years) and 95 women (mean age 57.6 years, range 7-85 years). Two hundred and fifty-nine (79.9%) port systems were placed under electrographic control of the catheter tip position. Duration of procedure, long-term device function, and complications such as infections, occlusions, dislocations, and thrombosis were all retrospectively measured and recorded until removal of the device, patient's death or the last known recorded documentation. RESULTS: In total, 359 devices have been used in 348 surgical procedures, 324 implantations (90.25%), and 35 explantations (9.75%). Port systems were implanted using the cephalic vein in 275 patients (84.9%), and in 49 (15.1%), the subclavian vein was used for insertion of the catheter. Mean surgical implantation time was 38.8 min (15-85 min). The median follow-up was 490.6 days (range 2-2,568); 159,764 catheter days (mean, 234 days, range 2-2,604) were documented. Of 35 explanted devices, the explantation was necessary due to complications in 28 cases (8.6%) with infection n = 6 (1.9%, 0.037 per 1,000 catheter days), occlusion n = 8 (2.5%, 0.050 per 1,000 catheter days), dislocation n = 7 (2.2%, 0.044 per 1,000 catheter days), deep vein thrombosis of the upper extremity n = 6 (1.9%, 0.037 per 1,000 catheter days), and clotting n = 1 (0.3%, 0.006 per 1,000 catheter days). Premature catheter removal (<30d post-operatively) was required in 6 patients (1.9%, 0.037 per 1,000 catheter days) due to complications: 3 catheter dislocations/malfunctions (0.9%, 0.019 per 1,000 catheter days), one port related infection, one pocket port infection, and one deep vein thrombosis of the upper extremity (0.3%, 0.006 per 1,000 catheter days). CONCLUSIONS: The intra-atrial ECG techniques to judge correct tip positioning for central venous port implantations are simple and economical. The exact position can be determined intraoperatively. It can justify a delayed postoperative chest X-ray to confirm CVC line tip placement. Nevertheless, the procedure and handling of the device later on has to be performed with care in order to avoid infections and technical problems.


Assuntos
Infecções Relacionadas a Cateter/etiologia , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Cateteres de Demora , Eletrocardiografia/métodos , Trombose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Relacionadas a Cateter/epidemiologia , Criança , Remoção de Dispositivo , Sistemas de Liberação de Medicamentos , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Nutrição Parenteral , Estudos Retrospectivos , Trombose/epidemiologia , Fatores de Tempo , Adulto Jovem
6.
World J Urol ; 29(5): 651-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21290131

RESUMO

PURPOSE: Urinary extravasation at the anastomosis is common after radical prostatectomies. Nevertheless, no data exist referring to the optimal date of catheter removal at the time of expected complete tightness of the leakage. Thus, we developed over the last 10 years a standardized concept to check the anastomosis, evaluating urinary extravasation using a dynamic transrectal ultrasound (dTRUS). METHODS: From 1999 to 2008, 1,479 radical prostatectomies have been performed. For complete tightness, 752 could be evaluated using the standardized concept of checking the anastomosis. The first 250 patients have been evaluated by cystogram and dTRUS and the following 502 patients only by dTRUS postoperatively. The date of checking the anastomosis was determined by the urine color. RESULTS: Urinary extravasation could be detected 4-8 days postoperatively in 41% (n = 308), 9-12 days in 16% (n = 120), 13-20 days in 8% (n = 60), and in no patient after 21 days. The coefficient of correlation comparing dTRUS versus cystogram was r = 0.99, P < 0.05. The measured volume of urinary extravasation after 4-8 days postoperatively was 15 ml (3-49 ml) using dTRUS and 16 ml (3-45 ml) using cystogram. After 9-20 days, the volume was determined as 9 ml (3-24 ml) by dTRUS and 9 ml (4-23 ml) by cystogram. The macroscopic evaluation of the urinary color was very well correlated with the likelihood of extravasation being still present. When the urine was cloudy or colored by old blood, extravasation was present in 96.9% of the patients. Microscopic evaluation like leukocyturia or hematuria of the urine on the same day shows specificity in only 34.3%. CONCLUSIONS: Following radical prostatectomy, the urine color is essential to assess the chance of a persisting leakage at the anastomosis. The method of dTRUS can replace the cystogram in checking for complete healing of the anastomosis, thus decreasing the exposure to X-rays of the patient of about 60 cGy/cm(2).


Assuntos
Fístula Anastomótica/prevenção & controle , Prostatectomia/normas , Uretra/diagnóstico por imagem , Uretra/cirurgia , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Anastomose Cirúrgica/normas , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia/métodos , Radiografia , Ultrassonografia
7.
Cancer Lett ; 264(1): 1-10, 2008 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-18353542

RESUMO

Ceramide has been shown to be capable to trigger apoptosis in almost any cell, including tumor cells. Ceramide is generated by a de novo pathway or by sphingomyelinases. Sphingomyelinases hydrolyze sphingomyelin in biological membranes to release ceramide and they are named acid, neutral and alkaline sphingomyelinase depending on their maximum activity at acid, neutral and alkaline pH values, respectively. Stimuli that trigger a release of ceramide to mediate apoptosis include CD95, TNF-receptor, DR5, gamma-irradiation, cytotoxic drugs, UV-light, bacteria, viruses, some forms of developmental death, anti-CD20 and disruption of the cell's contact with its matrix, to name a few. Here, we will focus on the role of acid sphingomyelinase in malignant tumors, which function in apoptosis is best characterized and documented by genetic models. We will discuss concepts that unify the biological actions of ceramide and describe the role of ceramide in important anti-tumor treatment modalities, such as gamma-irradiation and chemotherapy.


Assuntos
Apoptose/efeitos dos fármacos , Ceramidas/uso terapêutico , Neoplasias/tratamento farmacológico , Esfingomielina Fosfodiesterase/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Ceramidas/metabolismo , Humanos , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Neoplasias/metabolismo , Neoplasias/radioterapia , Transdução de Sinais/efeitos dos fármacos , Esfingomielina Fosfodiesterase/metabolismo
8.
Nuklearmedizin ; 55(5): 177-86, 2016 Sep 26.
Artigo em Alemão | MEDLINE | ID: mdl-27417067

RESUMO

This document describes the guideline for therapy of bone metastases with radium-223 ((223)Ra) published by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften in Germany (AWMF) under the auspices of the Deutsche Gesellschaft für Nuklearmedizin (DGN), Östereichische Gesellschaft für Nuklearmedizin (OGN), and Schweizerische Gesellschaft für Nuklearmedizin (SGNM). This guidance is based on an interdisciplinary consensus. These recommendations are a prerequisite for the quality management in the treatment of patients with bone metastases from prostate cancer using (223)Ra. They are aimed at guiding nuclear medicine specialists in selecting candidates to receive therapy and to deliver the treatment in a safe and effective manner. The document contains background information and definitions. It covers the rationale, indications and contraindications for therapy with (223)Ra. Essential topics are the requirements for institutions performing the therapy, which patient data have to be available prior to performance of therapy, and how treatment has to be carried out technically and organisationally. Moreover, essential elements of follow-up and aftercare are specified. As a matter of principle, the treatment inclusive aftercare has to be realised in close cooperation with the involved medical disciplines.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Medicina Nuclear/normas , Guias de Prática Clínica como Assunto , Radioterapia/normas , Rádio (Elemento)/uso terapêutico , Medicina Baseada em Evidências , Alemanha , Compostos Radiofarmacêuticos/normas , Compostos Radiofarmacêuticos/uso terapêutico , Rádio (Elemento)/normas , Resultado do Tratamento
9.
Eur Urol ; 68(5): 837-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25952317

RESUMO

BACKGROUND: Understanding how to sequence targeted therapies for metastatic renal cell carcinoma (mRCC) is important for maximisation of clinical benefit. OBJECTIVES: To prospectively evaluate sequential use of the multikinase inhibitors sorafenib followed by sunitinib (So-Su) versus sunitinib followed by sorafenib (Su-So) in patients with mRCC. DESIGN, SETTING, AND PARTICIPANTS: The multicentre, randomised, open-label, phase 3 SWITCH study assessed So-Su versus Su-So in patients with mRCC without prior systemic therapy, and stratified by Memorial Sloan Kettering Cancer Center risk score (favourable or intermediate). INTERVENTION: Patients were randomised to sorafenib 400mg twice daily followed, on progression or intolerable toxicity, by sunitinib 50mg once daily (4 wk on, 2 wk off) (So-Su), or vice versa (Su-So). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was improvement in progression-free survival (PFS) with So-Su versus Su-So, assessed from randomisation to progression or death during second-line therapy. Secondary endpoints included overall survival (OS) and safety. RESULTS AND LIMITATIONS: In total, 365 patients were randomised (So-Su, n=182; Su-So, n=183). There was no significant difference in total PFS between So-Su and Su-So (median 12.5 vs 14.9 mo; hazard ratio [HR] 1.01; 90% confidence interval [CI] 0.81-1.27; p=0.5 for superiority). OS was similar for So-Su and Su-So (median 31.5 and 30.2 mo; HR 1.00, 90% CI 0.77-1.30; p=0.5 for superiority). More So-Su patients than Su-So patients reached protocol-defined second-line therapy (57% vs 42%). Overall, adverse event rates were generally similar between the treatment arms. The most frequent any-grade treatment-emergent first-line adverse events were diarrhoea (54%) and hand-foot skin reaction (39%) for sorafenib; and diarrhoea (40%) and fatigue (40%) for sunitinib. CONCLUSIONS: Total PFS was not superior with So-Su versus Su-So. These results demonstrate that sorafenib followed by sunitinib and vice versa provide similar clinical benefit in mRCC. PATIENT SUMMARY: We investigated if total progression-free survival (PFS) is improved in patients with advanced/metastatic kidney cancer who are treated with sorafenib and then with sunitinib (So-Su), compared with sunitinib and then sorafenib (Su-So). We found that total PFS was not improved with So-Su compared with Su-So, but both treatment options were similarly effective in patients with advanced/metastatic kidney cancer. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00732914, www.clinicaltrials.gov.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Carcinoma de Células Renais/tratamento farmacológico , Indóis/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Pirróis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/secundário , Carcinoma de Células Renais/secundário , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/patologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Modelos de Riscos Proporcionais , Sorafenibe , Sunitinibe
10.
PLoS One ; 9(7): e101571, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25033396

RESUMO

PURPOSE: To characterize intermediate and high-risk prostate carcinomas with measurements of standardized uptake values (SUVs) and apparent diffusion coefficient (ADC) values by means of simultaneous [18F] choline PET/MRI. MATERIALS AND METHODS: 35 patients with primary prostate cancer underwent simultaneous [18F] choline PET/MRI. From these, 21 patients with an intermediate and high risk constellation who were not under ongoing hormonal therapy were included. Altogether 32 tumor lesions with a focal uptake of [18F] choline could be identified. Average ADC values (ADCaver) minimum ADC values (ADCmin) as well as maximum and mean SUVs (SUVmax, SUVmean) of tumor lesions were assessed with volume-of-interest (VOI) and Region-of-interest (ROI) measurements. As a reference, also ADCaver, ADCmin and SUVmax and SUVmean of non-tumorous prostate tissue were measured. Statistical analysis comprised calculation of descriptive parameters and calculation of Pearson's product moment correlations between ADC values and SUVs of tumor lesions. RESULTS: Mean ADCaver and ADCmin of tumor lesions were 0.94±0.22×10(-3) mm2/s and 0.65±0.21×10(-3) mm2/s, respectively. Mean SUVmax and SUVmean of tumor lesions were 6.3±2.3 and 2.6±0.8, respectively. These values were in each case significantly different from the reference values (p<0.001). There was no significant correlation between the measured SUVs and ADC values (SUVmax vs. ADCaver: R = -0.24, p = 0.179; SUVmax vs. ADCmin: R = -0.03, p = 0.877; SUVmean vs. ADCaver: R = -0.27, p = 0.136; SUVmean vs. ADCmin: R = -0.08, p = 0.679). CONCLUSION: Both SUVs and ADC values differ significantly between tumor lesions and healthy tissue. However, there is no significant correlation between these two parameters. This might be explained by the fact that SUVs and ADC values characterize different parts of tumor biology.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Biópsia , Colina/metabolismo , Diagnóstico por Imagem , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Radiografia , Compostos Radiofarmacêuticos
11.
J Leukoc Biol ; 89(2): 311-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21106641

RESUMO

In tumor-bearing mice, immunosuppressive granulocytic and monocytic MDSC have been identified. The identity and function of MDSC in cancer patients are less clear and need further characterization. We analyzed the peripheral blood of 103 patients with HNC, lung cancer, or cancers of bladder and ureter. Based on sedimentation properties in density gradients, a subset of LD-PMN was identified and analyzed. LD-PMN were expanded in the peripheral blood of cancer patients, suppressed proliferation, and IFN-γ production of polyclonally stimulated T cells and thus, qualify as human MDSC. Immunophenotyping and morphological analysis revealed the accumulation of immature PMN in the MDSC fraction. Neutrophilic MDSC showed altered surface marker expression, prolonged survival, and impaired effector functions when compared with conventional, mature PMN of regular density. MDSC displayed markedly reduced chemotaxis toward tumor-conditioned medium and lacked expression of chemokine receptors CXCR1 and CXCR2, which are normally required for PMN extravasation from the bloodstream and subsequent tissue infiltration. Collectively, our data suggest the accumulation and persistence of long-lived, immature granulocytic MDSC with T cell-suppressive function and impaired migratory properties in the peripheral blood of cancer patients.


Assuntos
Carcinoma de Células Escamosas/patologia , Diferenciação Celular/imunologia , Quimiotaxia de Leucócito/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Células Progenitoras Mieloides/imunologia , Células Progenitoras Mieloides/patologia , Neutrófilos/imunologia , Neutrófilos/patologia , Apoptose/imunologia , Carcinoma de Células Escamosas/imunologia , Sobrevivência Celular/imunologia , Feminino , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Hospedeiro Imunocomprometido/imunologia , Masculino , Células Tumorais Cultivadas
12.
Arch Biochem Biophys ; 462(2): 171-5, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17467652

RESUMO

Ceramide generated in the cell membrane has been shown to be central for the induction of apoptosis by death receptors and many stress stimuli such as gamma-irradiation, UV-light or infection with pathogens. Ceramide reorganizes cell membranes and forms large ceramide-enriched membrane domains that serve the spatial and temporal organization of the cellular signalosome upon activation. Thus, ceramide-enriched membrane domains mediate clustering of CD95 and DR5 to facilitate apoptosis, and they are also critically involved in apoptosis after irradiation, UV-light and infection with Pseudomonas aeruginosa. Since ceramide-enriched membrane domains amplify signals, their function is not restricted to the induction of apoptosis and it was shown that ceramide-enriched membrane domains are also involved in internalization of pathogens and the control of cytokine release from infected epithelial cells. Recent studies support the notion that changes of the ceramide metabolism are also critically involved in human diseases, for instance neurological disorders, cancer, infectious diseases and Wilson's disease.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/fisiologia , Membrana Celular/metabolismo , Ceramidas/metabolismo , Infecções/metabolismo , Doenças do Sistema Nervoso/metabolismo , Receptores de Morte Celular/metabolismo , Animais , Citoproteção/fisiologia , Humanos , Infecções/patologia , Doenças do Sistema Nervoso/patologia , Estresse Oxidativo/fisiologia
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