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Von Hippel-Lindau (VHL) disease is the main cause of inherited clear-cell renal cell carcinoma (ccRCC) and is caused by germline mutations in the VHL tumor suppressor gene. Bi-allelic VHL alterations lead to inactivation of pVHL, which plays a major role by downstream activation of the hypoxia inducible factor (HIF) pathway. Somatic VHL mutations occur in 80% of sporadic ccRCC cases and the second most frequently mutated gene is polybromo 1 (PBRM1). As there is currently no data regarding PBRM1 involvement in VHL disease-associated ccRCC, the aim of the present study was to assess the PBRM1 mutational status, and PBRM1 and HIF expression in VHL disease-associated ccRCC series compared with a sporadic series. PBRM1 gene was screened by Sanger sequencing for 23 VHL-disease-associated ccRCC and 22 sporadic ccRCC cases. Immunohistochemical studies were performed to detect the expression of PBRM1, HIF1 and HIF2 for all cases. In VHL-associated tumors, 13.0% (n=3/23) had PBRM1 somatic mutations and 17.4% (n=4/23) had a loss of PBRM1 nuclear expression. In sporadic cases, 27.3% (n=6/22) showed PBRM1 somatic mutations and 45.5% (n=10/22) had a loss of PBRM1 nuclear expression. Loss of PBRM1 was associated with an advanced tumor stage. HIF1-positive tumors were observed more frequently in the VHL-associated ccRCC than in the sporadic series. Furthermore, in the VHL cohort, PBRM1 expression appeared to be associated more with HIF1 than with HIF2. Given that hereditary tumors tend to be less aggressive, these results would suggest that co-expression of PBRM1 and HIF1 may have a less oncogenic role in VHL-associated ccRCC.
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BACKGROUND: Intracardiac masses are relatively rare but the diagnosis can be challenging for the cardiologist and the clinical presentation can be misleading. While most of the cardiac masses are benign, malignant masses are mostly metastatic tumours. CASE SUMMARY: An 81-year-old man was admitted to the cardiology department for congestive heart failure with the complaint of recent dyspnoea. The initial electrocardiogram was suggestive of a late presentation of an anterior myocardial infarction. Blood test showed mild and stable elevation of troponin and brain natriuretic peptide. Doppler-echocardiography revealed an interventricular septal thickening. Contrast echocardiography revealed a mass with a possibly necrotic centre and peripheral hypervascularization. Cardiac computed tomography (CT) confirmed the existence of a cardiac tumour with a hypodense centre and also revealed the presence of a large tumour of the lung's left lower lobe with multiple enlarged lymph nodes associated with possible left adrenal gland metastasis. Computed tomography-guided percutaneous biopsy of the pulmonary mass demonstrated a squamous cell lung cancer which was likely the primary cancer. The patient was discharged home waiting for chemotherapy to start but died a few days later at home of an unknown cause. DISCUSSION: Diagnosis of intracardiac mass is difficult, often requiring multiple imaging modalities. Contrast-enhanced echocardiography may help early diagnosis and can be easily implemented with other imaging modalities such as cardiac magnetic resonance imaging or CT.
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BACKGROUND: Smoking is a strong risk factor for cancer and atherosclerosis. Cancer mortality, especially from lung cancer, overtakes cardiovascular (CV) death rate in patients with peripheral arterial disease (PAD). Only a few patients with lung cancer after PAD management may benefit from surgical excision. Circulating tumor cells (CTC) associated with low-dose chest CT (LDCT) may improve early cancer detection. This study focuses on a screening strategy that can address not only lung cancer but all tobacco-related cancers in this high-risk population. METHODS: DETECTOR Project is a prospective cohort study in two French University hospitals. Participants are smokers or former smokers (≥30 pack-years, quitted ≤15 years), aged ≥55 to 80 years, with atherosclerotic PAD or abdominal aortic aneurysm. After the first screening round combining LDCT and CTC search on a blood sample, two other screening rounds will be performed at one-year interval. Incidental lung nodule volume, volume doubling time and presence of CTC will be taken into consideration for adapted diagnostic management. In case of negative LDCT and presence of CTC, a contrast enhanced whole-body PET/CT will be performed for extra-pulmonary malignancy screening. Psychological impact of this screening strategy will be evaluated in population study using a qualitative methodology. Assuming 10% prevalence of smoking-associated cancer in the studied population, a total of at least 300 participants will be enrolled. DISCUSSION: Epidemiological data underline an increase incidence in cancer and related death in the follow-up of patients with PAD, compared with the general population, particularly for tobacco-related cancers. The clinical benefit of a special workup for neoplasms in patients with PAD and a history of cigarette smoking has never been investigated. By considering CTCs detection in this very high-risk selected PAD population for tobacco-induced cancer, we expect to detect earlier pulmonary and extra-pulmonary malignancies, at a potentially curable stage. TRIAL REGISTRATION: The study was registered in the French National Agency for Medicines and Health Products Safety (No N° EUDRACT_ID RCB: 2016-A00657-44) and was approved by the ethics Committee for Persons Protection (IRB number 1072 and n° initial agreement 2016-08-02; ClinicalTrials.gov identifier NCT02849041).
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Detecção Precoce de Câncer , Neoplasias/sangue , Células Neoplásicas Circulantes/patologia , Doença Arterial Periférica/sangue , Fumar/sangue , Idoso , Idoso de 80 Anos ou mais , Ex-Fumantes , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Neoplasias/diagnóstico por imagem , Neoplasias/epidemiologia , Neoplasias/patologia , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/epidemiologia , Doença Arterial Periférica/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Risco , Fumantes , Fumar/efeitos adversos , Fumar/epidemiologia , Fumar/patologia , Abandono do Hábito de FumarRESUMO
BACKGROUND: There are no comparative data on pathological predictors at diagnosis, between African Caribbean and Caucasian men with prostate cancer (PCa), in equal-access centers. The objective of this study was to evaluate the grade groups of an African Caribbean cohort, newly diagnosed with PCa on prostate biopsy, compared with a Caucasian French Metropolitan cohort. METHODS: A retrospective, a comparative study was conducted between 2008 and 2016 between the University Hospital of Martinique in the French Caribbean West Indies, and the Saint Joseph Hospital in Paris. Clinical, biological, and pathological data were collected at diagnosis. The primary outcome was the grade groups for Gleason score; the secondary outcome was the PCa detection rate. Multivariate analysis was performed using linear regression. RESULTS: Of the 1880 consecutive prostate biopsy performed in the African Caribbean cohort, 945 had a diagnosis of PCa (50.3%) and 500 of 945 in the French cohort (33.8%). African Caribbean patients were older (mean 68.5 vs 67.5 years; P = .028), had worse clinical stage (13.2% vs 5.2% cT3-4; P < .001) and higher median prostate-specific antigen (PSA) level (9.23 vs 8.32 ng/mL; P = .019). On univariate analysis, African Caribbean patients had worse pathological grade groups than French patients (P < .001). Nevertheless, after adjustment on age, stage, and PSA, there were no significant differences between the two cohorts (P = .903). CONCLUSION: African Caribbean patients presented higher PCa detection rate, and higher grade groups at diagnosis than French patients in equal-access centers on univariate analysis but not on multivariate analysis. African Caribbean patients with equivalent clinical and biological characteristics than Caucasian patients at diagnosis might expect the same prognosis for PCa.
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População Negra , Neoplasias da Próstata/patologia , Idoso , Biópsia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Paris , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/química , Estudos Retrospectivos , Fatores de Risco , Regulador Transcricional ERG/análise , Índias Ocidentais , População BrancaRESUMO
The spontaneously hypertensive rat model with reduced NO synthesis (SHRLN) shares features with aging and hypertension in humans, among other a severe aortic stiffening. The present in vivo study aimed to compare thoracic (TA) and abdominal (AA) aortic stiffness in the SHRLN (treated 5 weeks with L-NAME), SHR, and normotensive Wistar Kyoto (WKY). Dynamic properties of TA and AA were measured in the same rats, using echotracking recording of aortic diameter coupled with blood pressure (BP). Measurements were performed first at operating BP and then after BP reduction in hypertensive rats, thus in isobaric conditions. Histological staining and immunohistochemistry were used for structural analysis at both sites. At operating pressure, BP and pulse pressure (PP) were higher in SHRLN compared with SHR. Stiffness index was also increased and distensibility decreased in both TA and AA in SHRLN. At WKY-matched blood pressure, isobaric AA parameters remained specifically altered in SHRLN, whereas TA recovered to values identical to WKYs. Collagen, fibronectin, α5-selectin, and FAK were increased in SHRLN compared with SHR or WKY. Nevertheless, only the strong accumulations of fibronectin and collagen at the AA site in SHRLN were associated with intrinsic stiffening. In conclusion, we confirm that NO restriction associated with hypertension induces a severe pathological phenotype and shows that L-NAME induced stiffening is more pronounced in AA than in TA as a result of greater fibrosis.
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Overall survival of patients with metastatic non-small cell lung cancer (NSCLC) has significantly improved with platinum-based salt treatments and recently with targeted therapies and immunotherapies. However, treatment failure occurs due to acquired or emerging tumor resistance. We developed a monoclonal antibody against the proform of neurotensin (LF-NTS mAb) that alters the homeostasis of tumors overexpressing NTSR1. Neurotensin is frequently overexpressed along with its high affinity receptor (NTSR1) in tumors from epithelial origins. This ligand/receptor complex contributes to the progression of many tumor types by activation of the cellular effects involved in tumor progression (proliferation, survival, migration, and invasion). We demonstrate that LF-NTS mAb operates on the plasticity of tumor cells overexpressing NTSR1 and lowers their aggressiveness. The mAb enables the restoration of platinum-based therapies responsiveness, while also decreasing metastatic processes. Efficacy dosage with long-term treatment showed no obvious adverse events, while demonstrating improvement in the performance status. Our data suggests that LF-NTS mAb is an ideal candidate to be safely added to the conventional standard of care in order to improve its efficacy.
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Adenocarcinoma de Pulmão/tratamento farmacológico , Anticorpos Monoclonais/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neurotensina/antagonistas & inibidores , Receptores de Neurotensina/antagonistas & inibidores , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Animais , Antineoplásicos/farmacologia , Apoptose , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neurotensina/imunologia , Neurotensina/metabolismo , Prognóstico , Receptores de Neurotensina/imunologia , Receptores de Neurotensina/metabolismo , Estudos Retrospectivos , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Central artery stiffening is recognized as a cardiovascular risk. The effects of hypertension and aging have been shown in human and animal models but the effect of salt is still controversial. We studied the effect of a high-salt diet on aortic stiffness in salt-sensitive spontaneously hypersensitive stroke-prone rats (SHRSP). Distensibility, distension, and ß-stiffness were measured at thoracic and abdominal aortic sites in the same rats, using echotracking recording of the aortic diameter coupled with blood pressure (BP), in SHRSP-salt (5% salted diet, 5 weeks), SHRSP, and normotensive Wistar-Kyoto (WKY) rats. Hemodynamic parameters were measured at BP matched to that of WKY. Histological staining and immunohistochemistry were used for structural analysis. Hemodynamic isobaric parameters in SHRSP did not differ from WKY and only those from the abdominal aorta of SHRSP-salt presented decreased distensibility and increased stiffness compared with WKY and SHRSP. The abdominal and thoracic aortas presented similar thickening, increased fibrosis, and remodeling with no change in collagen content. SHRSP-salt presented a specific increased elastin disarray at the abdominal aorta level but a decrease in elastin content in the thoracic aorta. This study demonstrates the pro-stiffening effect of salt in addition to hypertension; it shows that only the abdominal aorta presents a specific pressure-independent stiffening, in which elastin disarray is likely a key mechanism.
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Aorta Abdominal/fisiopatologia , Aorta Torácica/fisiopatologia , Pressão Arterial , Hipertensão/fisiopatologia , Cloreto de Sódio na Dieta , Rigidez Vascular , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Modelos Animais de Doenças , Elastina/metabolismo , Fibrose , Hipertensão/etiologia , Hipertensão/metabolismo , Hipertensão/patologia , Masculino , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Remodelação VascularRESUMO
Theranostic assays are based on single-gene testing, but the ability of next-generation sequencing (NGS) to interrogate numerous genetic alterations will progressively replace single-gene assays. Although NGS was evaluated to screen for theranostic mutations, its usefulness in clinical practice on large series of samples remains to be demonstrated. NGS performance was assessed following guidelines. TaqMan probes and NGS were compared for their ability to detect EGFR and KRAS mutations, and NGS mutation profiles were analyzed on a large series of non-small-cell lung cancers (n = 1343). The R2 correlation between expected and measured allelic ratio, using commercial samples, was >0.96. Mutation detection threshold was 2% for 10 ng of DNA input. κ Scores for TaqMan versus NGS were 0.99 (95% CI, 0.97-1.00) for EGFR and 0.98 (95% CI, 0.97-1.00) for KRAS after exclusion of rare EGFR (n = 40) and KRAS (n = 60) mutations. NGS identified 693 and 292 mutations in validated and potential oncogenic drivers, respectively. Significant associations were found between EGFR and PI3KCA or CTNNB1 and between KRAS and STK11. Potential oncogenic driver mutations or gene amplifications were more frequent in validated oncogenic driver nonmutated samples. This work is a proof of concept that targeted NGS is accessible in routine screening, including large screening, at reasonable cost. Clinical data should be collected and implemented in specific databases to make molecular data meaningful for direct patients' benefit.
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Carcinoma Pulmonar de Células não Pequenas/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Humanos , Mutação/genética , Oncogenes , Proteínas Proto-Oncogênicas p21(ras)/genética , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Limited data are available on the prevalence of oncogenic driver mutations in Caucasian populations, and especially in Europeans. AIM: To evaluate the targetable mutational spectra in unselected patients with lung adenocarcinoma in routine clinical practice from several French hospitals, using the same molecular platform. PATIENTS AND METHODS: Samples from 2,219 consecutive patients with histologically-proven advanced lung adenocarcinoma were centrally analysed at a referenced and certified diagnostic platform in order to test for activating and resistance mutations in EGFR, KRAS, BRAF, ERBB2 and PI3KCA. Demographic and clinical features were retrieved from the medical charts. Multivariate binary logistic regression was used to determine the independent predictive factors for the occurrence of specific mutations, in the whole study population or in selected subgroups. FINDINGS: The overall respective incidence of EGFR, KRAS, BRAF, ERBB2 and PI3KCA mutations was 10.5%, 0.9%, 25%, 1.5%, 2.1% and 1.4%, in our study sample including 87.4% white Caucasians, 10.8% Africans and 1.8% Asians; 60.6% men, 30.7% never smoker (median age: 68.3 years). Ethnicity was an independent predictor for EGFR, KRAS and ERBB2 gene abnormalities. In all cases, a significantly higher prevalence of targetable EGFR and ERBB2, and a lower prevalence of resistance KRAS mutations were observed in African women as compared to African men or Caucasians. CONCLUSIONS: In real life conditions of routine genetic testing, we have identified subsets of patients with specific targetable activating somatic mutations according to ethnicity, who could preferentially benefit from anti-EGFR and anti-ERBB2 targeted therapies.
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BACKGROUND: Enhanced aortic stiffness and blood pressure variability (BPV) are independent risk factors for cardiovascular disease and all-cause mortality in man. They are also correlated with increased blood pressure (BP) and/or arterial remodeling. However, the interplay between BP and BPV on the stiffening process is still unclear. Our objectives were to determine the temporal evolution of both BPV and pulse wave velocity (PWV), a surrogate measure of arterial stiffness, using an animal model of remodeling-dependent aortic stiffening. METHOD: We thus, developed a new telemetric technique allowing continuous measurement of PWV in conscious, unrestrained rats. Studies were performed in spontaneously hypertensive rats (SHR) treated for 2 weeks with N-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor (SHR-LN). BPV was evaluated conventionally or with a new device composed of two pressure transducers in two different sets of rats. This allowed a continuous monitoring of telemetered PWV, systolic (SPV), diastolic (DPV), and pulse pressure variability (PPV). Aortic structure was then characterized by immunohistochemical analysis. RESULTS: SPV, DPV, and PPV were increased in SHR-LN, when calculated by 24-h SD or using average real variability a parameter used to assess short-term variability in man. We observed rapid and simultaneous increases in BP, SPV, and PWV. Interestingly, PPV was the most increased parameter resulting mainly from different time course of SPV and DPV. Structural alterations of the aortic wall were observed, with a eutrophic inward remodeling and accumulation of fibronectin and its two main receptors (α5 and αv integrins). CONCLUSION: This offers unequivocal evidence of a significant relationship between PWV, BPV, and arterial structure.
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Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Rigidez Vascular/fisiologia , Animais , Modelos Cardiovasculares , Análise de Onda de Pulso , RatosRESUMO
Malignant melanoma is a tumour, which usually involves skin melanocytes. Involvement of the male genitourinary (GU) system by melanoma is an uncommon and challenging diagnosis. We report the first case of seminal vesicle metastasis from a primary cutaneous melanoma in a 58-year-old man, with hemospermia as the only clinical sign. This case highlights the role of multiparametric magnetic resonance imaging, as a more sensitive assessment to early detect metastatic melanoma in the GU system. The patient underwent a robot-assisted laparoscopic bilateral seminal vesiculectomy, which had good functional and oncological results and is still in complete remission at the 1-year follow-up.
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PURPOSE: To identify the MRI sequences producing the greatest pancreatic adenocarcinoma conspicuity and to assess correlations linking MRI signal intensity and apparent diffusion coefficient to histopathological findings. METHODS: We retrospectively included 22 patients with pancreatic adenocarcinoma who underwent MRI (1.5 or 3 T) before surgical resection. Fat-suppressed (FS) T1- and T2-weighted sequences; 3D FS dynamic T1-weighted gadolinium-enhanced gradient-echo (GRE) imaging at the arterial, portal, and delayed phases; and diffusion-weighted imaging (DWI) with b values of 600-800 s/mm(2) were reviewed. On each sequence, we assessed tumor conspicuity both qualitatively (3-point scale) and quantitatively (tumor-to-proximal and -distal pancreas contrast ratios), and we performed paired Wilcoxon tests to compare these data across sequences. We evaluated correlations between histopathological characteristics and MRI features. RESULTS: 21/22 (95%) tumors were hypointense by 3D FS T1 GRE arterial phase imaging, which produced the greatest tumor conspicuity (p ≤ 0.02). By DWI, 5/20 (25%) of tumors were isointense. The correlation between size by histology and MRI was strongest with DWI. A progressive enhancement pattern was associated with extensive and dense fibrous stroma (p ≤ 0.03). CONCLUSIONS: 3D FS T1 GRE arterial phase imaging produces greater pancreatic adenocarcinoma conspicuity compared to DWI but underestimates tumor size. DWI provides the best size evaluation but fails to delineate the tumor in one-fourth of cases.
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Adenocarcinoma/patologia , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/patologia , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Aumento da Imagem , Masculino , Meglumina , Pessoa de Meia-Idade , Compostos Organometálicos , Pâncreas/patologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
RATIONALE: Sinoaortic denervated (SAD) and chemically sympathectomized (SNX) rats are characterized by a decrease in arterial distensibility without hypertension and would, thus, be relevant for analyzing arterial wall stiffening independently of blood pressure level. The fibronectin network, which plays a pivotal role in cell-matrix interactions, is a major determinant of arterial stiffness. We hypothesized that in SAD and SNX rats, arterial stiffness is increased, due to alterations of cell-matrix anchoring leading to spatial reorganization of the extracellular matrix. METHODS: The intrinsic elastic properties of the arterial wall were evaluated in vivo by the relationship between incremental elastic modulus determined by echotracking and circumferential wall stress. The changes of cell-extracellular matrix links in the abdominal aorta were evaluated by studying fibronectin, vascular integrin receptors, and ultrastructural features of the aorta by immunochemistry. RESULTS: In both experimental conditions, wall stiffness increased, associated with different modifications of cell-extracellular matrix adhesion. In SAD rats, increased media cross-sectional area was coupled with an increase of muscle cell attachments to its extracellular matrix via fibronectin and its α5-ß1 integrin. In SNX rats, reduced media cross-sectional area was associated with upregulation of αv-ß3 integrin and more extensive connections between dense bands and elastic fibers despite the disruption of the elastic lamellae. CONCLUSION: In aorta of SNX and SAD rats, a similar arterial stiffness is associated to different structural alterations. An increase in αvß3 or α5ß1 integrins together with the already reported increase in the proportion of less distensible (collagen) to more distensible (elastin) components in both models contributes to remodeling and stiffening of the abdominal aorta.
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Aorta Abdominal/inervação , Aorta Abdominal/fisiopatologia , Fibronectinas/metabolismo , Nó Sinoatrial/inervação , Nó Sinoatrial/fisiopatologia , Rigidez Vascular/fisiologia , Animais , Aorta Abdominal/patologia , Denervação , Modelos Animais de Doenças , Matriz Extracelular/fisiologia , Hemodinâmica , Hipertensão/patologia , Hipertensão/fisiopatologia , Integrina alfa5/metabolismo , Masculino , Ratos , Ratos Wistar , Simpatectomia QuímicaAssuntos
Adenocarcinoma/patologia , Próstata/patologia , Neoplasias da Próstata/patologia , Idoso , Biópsia , Humanos , MasculinoAssuntos
Próstata/patologia , Hiperplasia Prostática/patologia , Biópsia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Cholestatic liver diseases leading to progressive destruction of intra-hepatic bile ducts and ductopenia encompass multiple etiologies. Pathophysiology and natural history of drug-induced cholangiopathies remain unclear. We report a case of prolonged ductopenia attributed to Tenoxicam (Tilcotil o--a non-steroidal anti-inflammatory drug of the oxicam family) ingested at therapeutic dose. A 36 year-old male patient was admitted for jaundice and Lyell syndrome starting 1 week after the ingestion of Tenoxicam. Liver biopsy showed cholestasis, non-suppurative cholangitis and polymorphous inflammatory infiltrate of the portal tracts (round cells, macrophages an eosinophils). Treatment with ursodesoxycholic acid and cholestyramine was instituted and the patient was asymptomatic 1 year after. Three years later mild biological cholestasis persisted and ductopenia was evidenced on liver biopsy. In this report we found that: (1) The toxicity of tenoxicam was probably mediated by an immunoallergic mechanism (Lyell syndrome and eosinophils on histology); (2) ductopenia was secondary to inflammatory cholangitis. Factors responsible for this chronic evolution are still unknown (genetic predisposition, vascular factors, etc.); and (3) the presence of ductopenia contrasted with the "clinical recovery" of the disease suggesting accessory bile drainage by cholangioles or partial reconstruction of the biliary tree.
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Anti-Inflamatórios não Esteroides/efeitos adversos , Ductos Biliares Intra-Hepáticos/patologia , Colestase Intra-Hepática/induzido quimicamente , Colestase Intra-Hepática/patologia , Piroxicam/análogos & derivados , Piroxicam/efeitos adversos , Adulto , Biópsia , Humanos , Cirrose Hepática Biliar/induzido quimicamente , Cirrose Hepática Biliar/patologia , MasculinoRESUMO
In spontaneous inflammatory arthritis of K/BxN T cell receptor transgenic mice, the effector phase of the disease is provoked by binding of immunoglobulins (Igs) to joint surfaces. Inflammatory cytokines are known to be involved in human inflammatory arthritis, in particular rheumatoid arthritis, although, overall, the pathogenetic mechanisms of the human affliction remain unclear. To explore the analogy between the K/BxN model and human patients, we assessed the role and relative importance of inflammatory cytokines in K/BxN joint inflammation by transferring arthritogenic serum into a panel of genetically deficient recipients. Interleukin (IL)-1 proved absolutely necessary. Tumor necrosis factor (TNF)-alpha was also required, although seemingly less critically than IL-1, because a proportion of TNF-alpha-deficient mice developed robust disease. There was no evidence for an important role for IL-6. Bone destruction and reconstruction were also examined. We found that all mice with strong inflammation exhibited the bone erosion and reconstruction phenomena typical of K/BxN arthritis, with no evidence of any particular requirement for TNFalpha for bone destruction. The variability in the requirement for TNF-alpha, reminiscent of that observed in treated rheumatoid arthritis patients, did not appear genetically programmed but related instead to subtle environmental changes.
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Anticorpos , Artrite Experimental/metabolismo , Citocinas/metabolismo , Interleucina-1/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Artrite Experimental/induzido quimicamente , Artrite Experimental/imunologia , Artrite Experimental/patologia , Citocinas/deficiência , Citocinas/genética , Modelos Animais de Doenças , Predisposição Genética para Doença , Imunização Passiva , Inflamação/metabolismo , Inflamação/patologia , Interleucina-6/deficiência , Interleucina-6/fisiologia , Camundongos , Camundongos Transgênicos , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Tarso Animal/patologiaRESUMO
Arthritis in the K/BxN mouse model is provoked by pathogenic antibodies (Abs) directed against a ubiquitously expressed protein, glucose-6-phosphate isomerase (GPI). To begin dissecting the repertoire of arthritogenic immunoglobulins (Igs) in the K/BxN model, and to provide a basis for comparison with RA patients we have generated anti-GPI monoclonal Abs (mAbs) from spontaneously activated B cells in the lymphoid organs of arthritic mice. B cell clones with anti-GPI specificities were present at extraordinarily high frequencies in the spleen, and less frequently in other lymphoid organs and in the synovial fluid. None of the anti-GPI mAbs induced arthritis when injected individually into healthy recipients, but most were effective when combined in pairs or larger pools. Arthritogenic combinations depended on mAbs of the IgG1 isotype, which bound to GPI with Kd in the 10(-9) M range, with no indication of cooperative binding between complementing pairs. Pathogenicity was not associated with recognition of a particular epitope, but the ability to form mAb/GPI multimers by simultaneous recognition of different epitopes was clearly required, consistent with the known role of complement and FcRs in this model. Sequence analysis revealed structural similarities amongst the mAbs, indicating that a particular subset of B cells may evade tolerance in K/BxN mice, and that affinity maturation by somatic mutation likely takes place. These results confirm that GPI itself, rather than a cross-reactive molecule, is the target of pathogenic Igs.
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Anticorpos Monoclonais/imunologia , Artrite Reumatoide/imunologia , Glucose-6-Fosfato Isomerase/imunologia , Animais , Afinidade de Anticorpos , Linfócitos B/imunologia , Células Clonais , Modelos Animais de Doenças , Feminino , Cinética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos TransgênicosRESUMO
K/BxN T cell receptor transgenic mice are a model of inflammatory arthritis, similar to rheumatoid arthritis. Disease in these animals is focused specifically on the joints but stems from autoreactivity to a ubiquitously expressed antigen, glucose-6-phosphate isomerase (GPI). T and B cells are both required for disease initiation, but anti-GPI immunoglobulins (Igs), alone, can induce arthritis in lymphocyte-deficient recipients. Here, we show that the arthritogenic Igs act through both Fc receptors (in particular, FcgammaRIII) and the complement network (C5a). Surprisingly, the alternative pathway of complement activation is critical, while classical pathway components are entirely dispensable. We suggest that autoimmune disease, even one that is organ specific, can occur when mobilization of an adaptive immune response results in runaway activation of the innate response.