RESUMEN
BACKGROUND: Palliative chemotherapy of advanced oesophageal squamous cell cancer (ESCC) consists of cisplatin/5-fluorouracil (CF) to target epidermal growth factor receptor (EGFR) with panitumumab (P); chemotherapy enhanced overall survival (OS) in advanced colorectal or squamous cell head and neck cancers. With prospective serum and tumour biomarkers, we tested if P added to CF (CFP) improved OS in advanced ESCC. PATIENTS AND METHODS: Eligible patients with confirmed ESCC that was not curatively resectable or did not qualify for definitive radiochemotherapy, were randomised 1 : 1 to receive CF [cisplatin (C) 100 mg/m2 i.v., day 1; 5-fluorouracil (F) 1000 mg/m2 i.v., days 1-4] or CF plus P (9 mg/kg, i.v., day 1, each q3-week cycle) until progressive disease or unacceptable toxicity. Safety was reviewed by the Data Safety Monitoring Board after 40, 70 and 100 patients who completed at least one cycle. After 53 enrolled patients, cisplatin was reduced from 100 mg/m2 to 80 mg/m2. RESULTS: The trial was stopped early based on interim efficacy results triggered by the third safety analysis: median OS (mOS) favoured CF over CFP, regardless of cisplatin dose [hazard ratio (HR) 1.77, 95% confidence interval (CI) 1.06-2.98; P = 0.028]. In the final analysis, mOS was 10.2 versus 9.4 months for CF versus CFP, respectively (HR 1.17, 95% CI 0.79-1.75; P = 0.43). One hundred (70.4%) of 142 patients in the safety population died, 51 (51.0%) with CFP. Most deaths were related to disease progression [44/49 (90%) deaths in CF versus 34/51 (67%) deaths in CFP]; objective responses [27/73 (37.0%)] were identical. The most common serious adverse events were kidney injury [3 (4.3%) versus 7 (9.7%)], general health deterioration [5 (7.1%) versus 5 (6.9%)] and dysphagia [4 (5.7%) versus 4 (5.6%)] in CF versus CFP, respectively. There were three (4.3%) and 17 (23.6%) common terminology criteria for adverse events (CTCAE) grade 5 events in CF versus CFP, respectively. Low soluble (s)EGFR levels were associated with better progression-free survival; sEGFR was induced under CFP. CONCLUSION: EGFR inhibition added to CF did not improve survival in unselected advanced ESCC patients. The results support further liquid biopsy studies. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01627379) and EudraCT (2010-020606-15).
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/tratamiento farmacológico , Cisplatino/efectos adversos , Supervivencia sin Enfermedad , Receptores ErbB/genética , Neoplasias Esofágicas/tratamiento farmacológico , Fluorouracilo/efectos adversos , Humanos , Panitumumab , Estudios Prospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: In contrast to exocrine pancreatic carcinomas, prognosis and treatment of pancreatic neuroendocrine neoplasms (PNEN) are significantly different. The variable growth pattern and associated clinical situation of functioning and non-functioning PNEN demand an individualized surgical approach. However, due to the scarce evidence associated with the rare disease, guidelines lack detailed recommendations for indication and for the required extent of surgical resection. METHODS: In a retrospective single-center study from 1990 to 2018, 239 patients with PNEN were identified. Clinical data were collected in the MaDoc database of the University Medical Center Mainz. A total of 155 non-functional PNEN were selected for further analysis. RESULTS: According to the classification of NET by the WHO in 2017, 28.8% (n = 40) of the tumors were G1, 61.9% (n = 86) G2, and 9.4% (n = 13) G3. In 73 patients, hepatic metastases were present. Sixty patients had lymph node metastasis. An R0 resection was achieved in 98 cases, an R1 situation in 10 cases. Five times, a tumor debulking was carried out (R2) and 5 times the operation was aborted without any resection because of the advanced tumor stage. A relapse occurred in 29 patients. Different prognostic factors (grade, tumor size, age) were analyzed. Grade-dependent 10-year overall survival rates were 79.5% (grade 1) and 60.1% (grade 2), respectively. The survival rate of grade 3 patients was limited to 66.7% after 13 months. CONCLUSION: In our study, patients with non-functioning PNEN had a longer overall survival after successful R0 resection. The risk analysis confirmed a Ki-67 cutoff value of 5%, which divided a high- and low-risk group. Patients with a PNEC G3 (Ki-67 index > 50%) had a very poor prognosis.
Asunto(s)
Tumores Neuroendocrinos/mortalidad , Neoplasias Pancreáticas/mortalidad , Adulto , Anciano , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/cirugía , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Pronóstico , Estudios Retrospectivos , RiesgoRESUMEN
This article contains parts of the doctoral thesis of F. Meyer.
RESUMEN
BACKGROUND: Drug-induced liver injury is increasing, especially in elderly patients with polymedication and multimorbidity. OBJECTIVES: Clinicopathologic correlation of immune-mediated liver injury, specifically liver injury following therapy with immune checkpoint inhibitors against PD-1, PDL-1, and CTLA4. METHODS: Histologic assessment of liver biopsies of nine patients after therapy with immune checkpoint inhibitors and correlation with clinical parameters. RESULTS: In all nine patients, liver injury was apparent after variable administration of immune checkpoint inhibitors. Transaminase levels were increased up to a maximum of 3818â¯U/l. Liver histology showed liver injury resembling autoimmune hepatitis respective cholangitis. In two patients, veno-occlusive disease was seen. Corticosteroid therapy was initiated in eight patients, subsequently four patients showed decreasing transaminases and five patients died of tumor progress. In three patients, it remains unclear whether liver injury by immune checkpoint inhibitors may have ultimately contributed to the fatal course, especially in one patient with liver cirrhosis and hepatocellular carcinoma. CONCLUSIONS: Therapy with immune checkpoint inhibitors may lead to potentially fatal immune phenomena in susceptible patients, which may affect liver and/or other organs independently. Other causes of hepatopathy need to be ruled out clinically and/or histologically.
Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Anticuerpos Monoclonales , Humanos , Factores Inmunológicos , Neoplasias HepáticasRESUMEN
This article presents the case of an IgG4-related disease in a patient with clinical signs of a malignant tumor of the oral cavity. After excluding the suspicion of a malignant lesion, vasculitis and various infectious diseases were ruled out. Finally, due to further immunohistochemical studies, IgG4-related disease was diagnosed.
Asunto(s)
Trastornos de Deglución , Enfermedad Relacionada con Inmunoglobulina G4 , Inmunoglobulina G , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/inmunología , Humanos , Enfermedad Relacionada con Inmunoglobulina G4/diagnósticoRESUMEN
BACKGROUND: Neuroendocrine Neoplasms of the small intestine have been noticed more frequently over the past 35 years. They constitute about 25% of all NENs and 29% of all tumors of the small intestine. Due to the predominantly indolent nature and overall good prognosis, the benefit of surgical treatment is still debated. METHODS: In a retrospective study, data of 83 surgically treated patients with neuroendocrine neoplasms of the small intestine, 48 males and 35 females with a median age of 62 years (range 25-86 years) were analyzed. Patient data were documented in the MaDoc database for neuroendocrine tumors of the University Medical Center of Mainz. IBM SPSS Statistics 20 was used for statistical analysis. Kaplan-Meier survival curves and Log-Rank tests, censoring patients at the time of last follow-up, were used to compare the overall survival depending on potential prognostic factors (stage, grade, surgical treatment). RESULTS: At the time of diagnoses, the most common clinical symptoms were abdominal pain (n = 31, 37.3%), bowel obstruction (n = 11, 13.3%), bowel perforation and peritonitis (n = 3, 3.6%), gastrointestinal bleeding (n = 9, 10.8%), weight loss (n = 11, 13.3%), and carcinoid syndrome (n = 27, 32.5%). 65 patients (78.3%) had lymph node metastasis and in 58 patients (69.9%) distant metastasis were present. Segmental bowel resection (44) was the most common surgical procedure, followed by right hemi-colectomy (32) and explorative laparotomy (7). In most patients (78.9%), lymphadenectomy (systematic/selective) was performed. The 5-year survival of patients who underwent a systematic or a selective lymphadenectomy differed significantly (82.2 vs. 40.0%). The overall 3-, 5-, and 10-year survival rates were 88.2, 80.3, and 71.0%, respectively. CONCLUSION: Mesenteric lymph node metastases are almost invariably present and have significant impact on patients' prognosis. Systematic lymphadenectomy prevents complications and improves the survival. Early surgical treatment should be the goal in order to prevent complications.
Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Intestino Delgado/patología , Tumores Neuroendocrinos/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Humanos , Intestino Delgado/cirugía , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/mortalidad , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia/tendenciasRESUMEN
BACKGROUND: Patients with neuroendocrine neoplasms (NEN) develop hepatic metastases in 50-95 %. The aims of this study were to evaluate the outcome/prognosis of patients following hepatic surgery and to identify predictive factors for the selection of patient that benefit from hepatic tumor resection. PATIENTS AND METHODS: In a retrospective single-center study (1990 to 2014), 204 patients with hepatic metastasis of NEN were included. Ninety-four were subjected to various forms of liver resection. According to the overall survival, the influence of several prognostic factors like the Ki-67 index, stage of disease, and resection status was evaluated. RESULTS: The primary tumor was located in the small intestine (n = 73), pancreas (n = 58), colon (n = 26), esophagus or stomach (n = 9) and in 38 patients the primary site was unknown. The Ki-67 index was associated with significant different overall survival. Patients with an R0 resection (n = 38) of their hepatic metastasis had a very good 10-year survival of 90.4 %. Patients in whom an R1 (n = 23) or R2 (n = 33) resection of their hepatic metastasis could be achieved had a 10-year survival of 53.4 and 51.4 %, respectively. The majority of the patients (53.9 %) could not be resected and had a poor 10-year survival rate of 19.4 %. Partial or complete control of endocrine-related symptoms was achieved in all patients with functioning tumors following surgery. The overall 5- and 10-year survival rates were 77.9 and 65.2 %, respectively. CONCLUSION: Surgical resection of hepatic NEN metastases can reduce symptoms and improve the survival in selected patients with a Ki-67 index less than 20 %. The expected outcome has to be compared to the outcome of alternative treatment strategies. An R0 situation should be the aim of hepatic surgery, but also patients with R1 or R2 resection show a good survival benefit.
Asunto(s)
Hepatectomía/métodos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Tumores Neuroendocrinos/patología , Selección de Paciente , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Femenino , Humanos , Antígeno Ki-67/sangre , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Novel devices for small-lumen ventilation may enable effective inspiration and expiratory ventilation assistance despite airway obstruction. In this study, we investigated a porcine model of complete upper airway obstruction. After ethical approval, we randomly assigned 13 anaesthetised pigs either to small-lumen ventilation following airway obstruction (n = 8) for 30 min, or to volume-controlled ventilation (sham setting, n = 5). Small-lumen ventilation enabled adequate gas exchange over 30 min. One animal died as a result of a tension pneumothorax in this setting. Redistribution of ventilation from dorsal to central compartments and significant impairment of the distribution of ventilation/perfusion occurred. Histopathology demonstrated considerable lung injury, predominantly through differences in the dorsal dependent lung regions. Small-lumen ventilation maintained adequate gas exchange in a porcine airway obstruction model. The use of this technique for 30 min by inexperienced clinicians was associated with considerable end-expiratory collapse leading to lung injury, and may also carry the risk of severe injury.
Asunto(s)
Obstrucción de las Vías Aéreas/terapia , Respiración Artificial/métodos , Lesión Pulmonar Aguda/etiología , Obstrucción de las Vías Aéreas/sangre , Obstrucción de las Vías Aéreas/fisiopatología , Animales , Modelos Animales de Enfermedad , Hemodinámica/fisiología , Masculino , Oxígeno/sangre , Presión Parcial , Intercambio Gaseoso Pulmonar/fisiología , Respiración Artificial/efectos adversos , Sus scrofa , Volumen de Ventilación Pulmonar/fisiología , Traqueotomía/métodosRESUMEN
Therapeutic agents to inhibit tumour necrosis factor alpha (TNF-α) have dramatically improved the treatment options for patients with autoimmune diseases. Common side effects include an increased susceptibility towards infection. Hepatic side effects are less frequently observed. Elevated liver function tests, hyperbilirubinaemia reactivation of chronic viral hepatitis or even acute liver failure have been described. Some cases have exhibited an autoimmune phenotype with the emergence of autoantibodies and characteristic histological lesions. We report on three patients who received anti-TNF therapy for psoriasis and presented with elevated liver function tests in the further course. Histological and serum analysis revealed an autoimmune phenotype of liver injury. In light of the growing use of anti-TNF therapies, drug-induced liver injury (DILI) with an autoimmune phenotype is an important side effect. Since the pathophysiological mechanisms related to the autoimmune phenotype of liver injury during TNF-inhibition are not well understood, the cases detailed herein should help treating physicians to improve their understanding of the situation.
Asunto(s)
Anticuerpos Monoclonales Humanizados/efectos adversos , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab , Enfermedades Autoinmunes/terapia , Enfermedad Hepática Inducida por Sustancias y Drogas/terapia , Femenino , Humanos , Persona de Mediana EdadRESUMEN
Pleural effusion often represents the first clinical symptom of lung carcinoma and malignant mesothelioma. As pleural punctation is performed quite early in the diagnostic procedure, effusion cytology frequently gives the first evidence about the presence of tumour cells and tumor histogenesis. In this study, we report on seven cases which were evaluated in our institution for the Employers' Liability Insurance Association, based solely on cytology findings.The mean age of the seven patients with a given long-term asbestos exposure during their working life was 81.7 years. On average eight smears per patient were investigated. In addition to routine cytology, immunocytochemistry, DNA image cytometry, AgNOR-analysis and fluorescence in situ hybridization were applied in a case-specific way. The results were interpreted against the clinical and occupational history of the respective patient.Definitive diagnosis could be made in six cases. In three of them, the diagnosis of malignant mesothelioma was made. Two cases were diagnosed as malignant effusion due to metastatic lung cancer. In one case, cells of high-grade Non-Hodgkin's lymphoma (NHL) were diagnosed and a malignant mesothelioma was excluded. In the last case, malignant mesothelioma could not be diagnosed unequivocally by cytology. In all seven cases, our interpretation was accepted by Employers' Liability Insurance Association. The five mesothelioma or lung cancer cases were accepted as asbestos-associated occupational disease, while the NHL case was rejected. In the last case, malignant mesothelioma was diagnosed later by autopsy, and the case was retroactively accepted as occupational disease.Cytology-based tumor diagnosis including adjuvant methods is a useful and reliable approach in cases of asbestos-associated tumours. Acceptance of occupational disease on the basis of cytological diagnoses even by the Employers' Liability Insurance Association helps avoid invasive pleural or lung biopsies in cases with an unequivocally positive effusion cytology of lung cancer or malignant mesothelioma.
Asunto(s)
Asbestosis/complicaciones , Asbestosis/patología , Mesotelioma/complicaciones , Mesotelioma/patología , Derrame Pleural/etiología , Derrame Pleural/patología , Anciano , Anciano de 80 o más Años , Humanos , Seguro por Accidentes , Neoplasias Pulmonares , Masculino , Enfermedades Profesionales/complicaciones , Enfermedades Profesionales/patologíaRESUMEN
INTRODUCTION: Due to their rarity and lack of prospective trials, the optimal treatment of pancreatic neuroendocrine neoplasms (PNENs) is still debated. Recommendations gathered by retrospective analyses of patient data should be based on the new classification of neuroendocrine neoplasms. METHODS: In a retrospective single-center study (1990 to 2012), 127 patients with PNENs were included. Tumor stage and type of resections were analyzed to evaluate successful treatment strategies. RESULTS: Seventy-nine patients (62 %) were diagnosed with stage I or II, 48 patients (38 %) with stage III or IV disease; 49.6 % of all PNENs were nonfunctional. Surgical interventions consisted of 50 enucleations, 27 distal resections, and 2 partial duodenopancreatectomies in patients with stage I or II disease. Twenty-eight patients with stage III or IV disease received a distal resection and in 13 patients, a partial duodenopancreatectomy was carried out. Exploration with debulking was performed in seven patients in stages III and IV. Stage-dependent 10-year survival rates were 93.7 (stages I and II, n = 79) and 56.0 % (stages III and IV, n = 48). CONCLUSIONS: PNENs have a good prognosis if they are well-differentiated and resected completely. Organ-preserving resection does not impair the prognosis in selected cases with stage I or II. In case of hepatic metastasis and advanced tumor stage, surgical reduction can reduce symptoms and improve the survival.
Asunto(s)
Tumores Neuroendocrinos/cirugía , Páncreas/cirugía , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Selección de Paciente , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Distribución de Chi-Cuadrado , Estudios de Cohortes , Toma de Decisiones , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/mortalidad , Análisis Multivariante , Invasividad Neoplásica/patología , Tumores Neuroendocrinos/mortalidad , Tumores Neuroendocrinos/patología , Páncreas/patología , Pancreatectomía/efectos adversos , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pancreaticoduodenectomía/métodos , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Adulto JovenRESUMEN
Even people which have never smoked can develop lung cancer. In this population a mutation in the exons 19-21 of the Epidermal Growth Factor Receptor (EGFR) can be detected. For this patient group targeted therapies with EGFR tyrosinkinase inhibitors are available. In this case report we describe a 37 year old non-smoker who developed a non-small cell lung cancer. Following therapy with Erlotinib a partial response could be achieved.
Asunto(s)
Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Nódulos Pulmonares Múltiples/complicaciones , Nódulos Pulmonares Múltiples/tratamiento farmacológico , Derrame Pericárdico/etiología , Derrame Pericárdico/prevención & control , Quinazolinas/uso terapéutico , Adulto , Clorhidrato de Erlotinib , Hemorragia/diagnóstico , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Nódulos Pulmonares Múltiples/diagnóstico , Derrame Pericárdico/diagnóstico , Inhibidores de Proteínas Quinasas/uso terapéutico , Fumar , Resultado del TratamientoRESUMEN
BACKGROUND/AIM: The aim of the study was to characterize the hepatic injury (HI) of the nonischemic liver lobe after selective portal triad clamping and investigate the influence of pharmacological pretreatment with alpha-lipoic acid (LA). METHODS: Brown-Norway rats received 500 micromol LA injected via the inferior vena cava 15 min prior to the induction of 90 min of selective ischemia. Another group of rats received vehicle prior to ischemia. Both groups were compared with sham-operated animals. RESULTS: Lipid peroxidation (LPO) was increased in the ischemic as well as in the nonischemic liver tissue (NIL) in the untreated group. Levels of adenosine triphosphate and reduced glutathione content of the nonischemic liver lobe were decreased in the untreated group 1 h after reperfusion. Activity of caspases 3 and 8 was not detectable, whereas expression of the Bax protein was demonstrated in the NIL. We observed areas of necrotic hepatocytes and large gaps of sinusoids in the NIL of the untreated rats. LA attenuated LPO as well as Bax expression in the NIL. Moreover adenosine triphosphate and glutathione content of the NIL was increased 1 h after reperfusion by LA. LA pretreatment reduced release of alpha-glutathione-s-transferase in plasma. Histology of the nonischemic liver lobe did not markedly differ from sham-operated animals after LA pretreatment. CONCLUSION: HI of the NIL seems to be mediated by LPO and proapoptotic proteins such as Bax. Besides its described potential to reduce ischemia/reperfusion injury of the ischemic lobe, LA attenuates HI of the nonischemic tissue after selective portal triad clamping.
Asunto(s)
Antioxidantes/farmacología , Isquemia/complicaciones , Hepatopatías/prevención & control , Hígado/efectos de los fármacos , Ácido Tióctico/farmacología , Animales , Antioxidantes/uso terapéutico , Constricción , Modelos Animales de Enfermedad , Peroxidación de Lípido/efectos de los fármacos , Hígado/irrigación sanguínea , Hepatopatías/etiología , Masculino , Ratas , Daño por Reperfusión/etiología , Daño por Reperfusión/prevención & control , Ácido Tióctico/uso terapéuticoRESUMEN
Apoptosis signaling is involved in both physiological tissue homeostasis and acute and chronic diseases. The role of regulatory apoptosis signaling molecules and their organ-specific functions are less defined. Therefore, we investigated the loss of the anti-apoptotic cellular FLICE-inhibitory protein (cFLIP) and the mechanisms of the resulting lethal organ failure in vivo using inducible knockout mice. These were generated by crossing floxed cFLIP mice to a tamoxifen inducible Rosa26-creERT2 mouse strain. Death following global loss of cFLIP resulted from liver failure, accumulation of M1-polarized macrophages and accompanying hepatic cell death and inflammation. Apoptosis was also prominent in immune cells, the kidney and intestinal epithelial cells (IECs) but not in cardiomyocytes. Cellular injury led to the release of damage-associated molecular patterns (DAMPs) and the induction of innate immune receptors including toll-like receptors (TLRs) 4 and 9, and stimulator of interferon genes (STING). Transplantation of bone marrow with intact cFLIP or depletion of macrophages prevented the phenotype of acute liver failure. Interestingly, compound deletion of cFLIP in bone marrow-derived cells and hepatocytes did not promote organ failure. Thus, cFLIP exerts a critical role in tissue homeostasis by preventing the activation of monocytic cells and innate immunity, which causes cell death and inflammation in susceptible tissues. These results encourage the development of organ-specific anti-apoptotic and anti-inflammatory therapies in acute organ failure.
Asunto(s)
Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/inmunología , Inmunidad Innata , Fallo Hepático Agudo/inmunología , Macrófagos/inmunología , Receptor Toll-Like 4/inmunología , Receptor Toll-Like 9/inmunología , Animales , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/genética , Hepatocitos/inmunología , Hepatocitos/patología , Fallo Hepático Agudo/genética , Fallo Hepático Agudo/patología , Macrófagos/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Transgénicos , Receptor Toll-Like 4/genética , Receptor Toll-Like 9/genéticaRESUMEN
Peroxisomes are cell organelles that perform multiple functions in the metabolism of lipids and of reactive oxygen species. They are present in most eukaryotic cells. However, they are believed to be absent in spermatozoa and they have never been described in male germ cells. We have used the immortalized germ cell line GC1spg to investigate the expression of peroxisomal proteins in germ cells of mice. The GC1spg cells represent the differentiation state of type B spermatogonia or preleptotene spermatocytes. We could show that peroxisomal membrane proteins like Pmp70 and Pex14p as well as peroxisomal matrix proteins like catalase or acyl CoA oxidase are expressed in GC1spg cells. All these proteins were colocalized in the same structures within the cells. Furthermore, by electron microscopy we have identified subcellular particles with an ultrastructural appearance that is characteristic of peroxisomes. This is the first report demonstrating the peroxisomal compartment in male germ cells of mice.
Asunto(s)
Peroxisomas/ultraestructura , Espermatogonias/ultraestructura , Animales , Línea Celular , Masculino , Ratones , Peroxisomas/química , Peroxisomas/metabolismo , Proteínas/análisis , Proteínas/metabolismo , Espermatogonias/citología , Espermatogonias/metabolismoRESUMEN
We present a nonradioactive in siru hybridization (ISH) protocol for detection of mRNAs in rat liver encoding for three peroxisomal proteins: catalase and urate oxidase as representatives of high-level abundance mRNAs and trifunctional protein (PH) as that of low-level abundance mRNAs. In addition to normal rats, animals treated for 24 hr with a single dose of bezafibrate were studied. The use of perfusion-fixation with 4% depolymerized paraformaldehyde/0.05% glutaraldehyde combined with paraffin embedding and the application of digoxigenin-labeled cRNA probes provided optimal cytological resolution and high sensitivity comparable to that of radioactive ISH. In parallel experiments, the same digoxigenin-labeled cRNA probes were used for Northern and semiquantitative dot-blot analysis of isolated RNAs. In control animals, the mRNAs for catalase and urate oxidase were uniformly distributed across the liver lobule and were confined to liver parenchymal cells. The bile duct epithelial and the sinusoidal cells remained negative. The specificity and the high resolution of our protocol were further substantiated by reciprocal localization of transcripts for albumin and glyceraldehyde-3-phosphate dehydrogenase in different regions of the liver lobule and for catalase in the proximal tubules of the renal cortex. Whereas in control livers the transcripts for PH were barely detectable, a strong signal was found in pericentral hepatocytes of bezafibratetreated animals, corresponding to an 8-10-fold increase of mRNA detected in dot-blots. In contrast, the urate oxidase mRNA was reduced by more than 50%, with diminution of staining in pericentral regions of the liver lobule. The mRNA encoding for catalase was only slightly affected. Further applications of this protocol should be helpful in elucidation of the cell-specific transcriptional regulation of peroxisomal proteins in various organs under normal and pathological conditions.
Asunto(s)
Bezafibrato/farmacología , Hipolipemiantes/farmacología , Hibridación in Situ/métodos , Hígado/química , Microcuerpos/química , Animales , Catalasa/aislamiento & purificación , Digoxigenina , Hígado/anatomía & histología , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Microcuerpos/efectos de los fármacos , Microcuerpos/enzimología , ARN Complementario , ARN Mensajero/aislamiento & purificación , Ratas , Ratas Sprague-Dawley , Distribución Tisular , Fijación del Tejido/métodos , Urato Oxidasa/aislamiento & purificaciónRESUMEN
The endemic occurrence of obesity and the associated risk factors that constitute the metabolic syndrome have been predicted to lead to a dramatic increase in chronic liver disease. Non-alcoholic steatohepatitis (NASH) has become the most frequent liver disease in countries with a high prevalence of obesity. In addition, hepatic steatosis and insulin resistance have been implicated in disease progression of other liver diseases, including chronic viral hepatitis and hepatocellular carcinoma. The molecular mechanisms underlying the link between insulin signaling and hepatocellular injury are only partly understood. We have explored the role of the antiapoptotic caspase-8 homolog cellular FLICE-inhibitory protein (cFLIP) on liver cell survival in a diabetic model with hypoinsulinemic diabetes in order to delineate the role of insulin signaling on hepatocellular survival. cFLIP regulates cellular injury from apoptosis signaling pathways, and loss of cFLIP was previously shown to promote injury from activated TNF and CD95/Apo-1 receptors. In mice lacking cFLIP in hepatocytes (flip(-/-)), loss of insulin following streptozotocin treatment resulted in caspase- and c-Jun N-terminal kinase (JNK)-dependent liver injury after 21 days. Substitution of insulin, inhibition of JNK using the SP600125 compound in vivo or genetic deletion of the mitogen-activated protein kinase (MAPK)9 (JNK2) in all tissues abolished the injurious effect. Strikingly, the difference in injury between wild-type and cFLIP-deficient mice occurred only in vivo and was accompanied by liver-infiltrating inflammatory cells with a trend toward increased amounts of NK1.1-positive cells and secretion of proinflammatory cytokines. Transfer of bone marrow from rag-1-deficient mice that are depleted from B and T lymphocytes prevented liver injury in flip(-/-) mice. These findings support a direct role of insulin on cellular survival by alternating the activation of injurious MAPK, caspases and the recruitment of inflammatory cells to the liver. Thus, increasing resistance to insulin signaling pathways in hepatocytes appears to be an important factor in the initiation and progression of chronic liver disease.