RESUMEN
BACKGROUND: Neoadjuvant chemoradiotherapy (CRT) is one of the preferred initial treatment strategies for locally advanced rectal cancer. Responses are variable, and most patients still require surgery. The aim of this study was to identify molecular mechanisms determining poor response to CRT. METHODS: Global gene expression and pathway enrichment were assessed in pretreatment biopsies from patients with non-metastatic cT2-4 N0-2 rectal cancer within 7 cm of the anal verge. Downstream Akt activation was assessed in an independent set of pretreatment biopsies and in colorectal cancer cell lines using immunohistochemistry and western blot respectively. The radiosensitizing effects of the Akt inhibitor MK2206 were assessed using clonogenic assays and xenografts in immunodeficient mice. RESULTS: A total of 350 differentially expressed genes were identified, of which 123 were upregulated and 199 downregulated in tumours from poor responders. Mitochondrial oxidative phosphorylation (P < 0·001) and phosphatidylinositol signalling pathways (P < 0·050) were identified as significantly enriched pathways among the set of differentially expressed genes. Deregulation of both pathways is known to result in Akt activation, and high immunoexpression of phosphorylated Akt S473 was observed among patients with a poor histological response (tumour regression grade 0-2) to CRT (75 per cent versus 48 per cent in those with a good or complete response; P = 0·016). Akt activation was also confirmed in the radioresistant cell line SW480, and a 50 per cent improvement in sensitivity to CRT was observed in vitro and in vivo when SW480 cells were exposed to the Akt inhibitor MK2206 in combination with radiation and 5-fluorouracil. CONCLUSION: Akt activation is a key event in the response to CRT. Pharmacological inhibition of Akt activation may enhance the effects of CRT. Surgical relevance Organ preservation is an attractive alternative in rectal cancer management following neoadjuvant chemoradiotherapy (CRT) to avoid the morbidity of radical surgery. Molecular steps associated with tumour response to CRT may provide a useful tool for the identification of patients who are candidates for no immediate surgery. In this study, tumours resistant to CRT were more likely to have activation of specific genetic pathways that result in phosphorylated Akt (pAkt) activation. Pretreatment biopsy tissues with high immunoexpression of pAkt were more likely to exhibit a poor histological response to CRT. In addition, the introduction of a pAkt inhibitor to cancer cell lines in vitro and in vivo led to a significant improvement in sensitivity to CRT. Identification of pAkt-activated tumours may thus allow the identification of poor responders to CRT. In addition, the concomitant use of pAkt inhibitors to increase sensitivity to CRT in patients with rectal cancer may constitute an interesting strategy for increasing the chance of a complete response to treatment and organ preservation.
Asunto(s)
Quimioradioterapia/métodos , Terapia Neoadyuvante/métodos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias del Recto/metabolismo , Anciano , Animales , Western Blotting , Línea Celular Tumoral , Ensayo de Unidades Formadoras de Colonias , Femenino , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Neoplasias del Recto/terapia , Transducción de Señal/efectos de los fármacos , Resultado del TratamientoRESUMEN
DAX1 transcription factor is a key determinant of adrenogonadal development, acting as a repressor of SF1 targets in steroidogenesis. It was recently demonstrated that DAX1 regulates pluripotency and differentiation in murine embryonic stem cells. In this study, we investigated DAX1 expression in adrenocortical tumors (ACTs) and correlated it with SF1 expression and clinical parameters. DAX1 and SF1 protein expression were assessed in 104 ACTs from 34 children (25 clinically benign and 9 malignant) and 70 adults (40 adenomas and 30 carcinomas). DAX1 gene expression was studied in 49 ACTs by quantitative real-time PCR. A strong DAX1 protein expression was demonstrated in 74% (25 out of 34) and 24% (17 out of 70) of pediatric and adult ACTs, respectively (χ(2)=10.1, p=0.002). In the pediatric group, ACTs with a strong DAX1 expression were diagnosed at earlier ages than ACTs with weak expression [median 1.2 (range, 0.5-4.5) vs. 2.2 (0.9-9.4), p=0.038]. DAX1 expression was not associated with functional status in ACTs. Interestingly, a positive correlation was observed between DAX1 and SF1 protein expression in both pediatric and adult ACTs (r=0.55 for each group separately; p<0.0001). In addition, DAX1 gene expression was significantly correlated with SF1 gene expression (p<0.0001, r=0.54). In conclusion, DAX1 strong protein expression was more frequent in pediatric than in adult ACTs. Additionally, DAX1 and SF1 expression positively correlated in ACTs, suggesting that these transcription factors might cooperate in adrenocortical tumorigenesis.
Asunto(s)
Neoplasias de la Corteza Suprarrenal/metabolismo , Carcinogénesis/metabolismo , Receptor Nuclear Huérfano DAX-1/metabolismo , Factor Esteroidogénico 1/metabolismo , Neoplasias de la Corteza Suprarrenal/genética , Adenoma Corticosuprarrenal/genética , Adenoma Corticosuprarrenal/metabolismo , Carcinoma Corticosuprarrenal/genética , Carcinoma Corticosuprarrenal/metabolismo , Adulto , Carcinogénesis/genética , Niño , Preescolar , Receptor Nuclear Huérfano DAX-1/genética , Femenino , Expresión Génica , Humanos , Lactante , Masculino , Persona de Mediana Edad , Factor Esteroidogénico 1/genéticaRESUMEN
Hepatic progenitor cells (HPCs) are bipotential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic or cholangiocytic lineages. HPCs are present in both hepatocellular (HCC) and cholangiocellular carcinoma (CC) in humans; and a small percentage of HCC can originate from cancer stem cells. However, its distribution in canine liver tumour has not been studied. Herein, we searched for stem/progenitor cells in 13 HCC and 7 CC archived samples by immunohistochemical analysis. We found that both liver tumours presented a higher amount of K19-positive HPCs. Besides, 61.6% of HCC cases presented immature CD44-positive hepatocytes. Nevertheless, only two cases presented CD133-positive cells. As observed in humans, hepatic canine tumours presented activated HPCs, with important differentiation onto hepatocytes-like cells and minimal role of cancer stem cells on HCC. These findings reiterate the applicability of canine model in the search for new therapies before application in humans.
Asunto(s)
Neoplasias de los Conductos Biliares/veterinaria , Conductos Biliares Intrahepáticos , Carcinoma Hepatocelular/veterinaria , Colangiocarcinoma/veterinaria , Enfermedades de los Perros/patología , Neoplasias Hepáticas/veterinaria , Células Madre/patología , Antígeno AC133 , Animales , Antígenos CD/inmunología , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Transformación Celular Neoplásica/patología , Colangiocarcinoma/patología , Modelos Animales de Enfermedad , Perros , Glicoproteínas/inmunología , Humanos , Receptores de Hialuranos/inmunología , Queratina-19/inmunología , Neoplasias Hepáticas/patología , Péptidos/inmunología , Antígeno Nuclear de Célula en Proliferación/metabolismoRESUMEN
Chronic hepatitis B (HBV) and C (HCV) virus infections are the most important factors associated with hepatocellular carcinoma (HCC), but tumor prognosis remains poor due to the lack of diagnostic biomarkers. In order to identify novel diagnostic markers and therapeutic targets, the gene expression profile associated with viral and non-viral HCC was assessed in 9 tumor samples by oligo-microarrays. The differentially expressed genes were examined using a z-score and KEGG pathway for the search of ontological biological processes. We selected a non-redundant set of 15 genes with the lowest P value for clustering samples into three groups using the non-supervised algorithm k-means. Fishers linear discriminant analysis was then applied in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Different transcriptional levels of genes were identified in HCC of different etiologies and from different HCC samples. When comparing HBV-HCC vs HCV-HCC, HBV-HCC/HCV-HCC vs non-viral (NV)-HCC, HBC-HCC vs NV-HCC, and HCV-HCC vs NV-HCC of the 58 non-redundant differentially expressed genes, only 6 genes (IKBKâ, CREBBP, WNT10B, PRDX6, ITGAV, and IFNAR1) were found to be associated with hepatic carcinogenesis. By combining trios, classifiers could be generated, which correctly classified 100 percent of the samples. This expression profiling may provide a useful tool for research into the pathophysiology of HCC. A detailed understanding of how these distinct genes are involved in molecular pathways is of fundamental importance to the development of effective HCC chemoprevention and treatment.
Asunto(s)
Humanos , Carcinoma Hepatocelular/genética , Perfilación de la Expresión Génica , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Neoplasias Hepáticas/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Carcinoma Hepatocelular/virología , Etiquetas de Secuencia Expresada , Neoplasias Hepáticas/virología , Biomarcadores de Tumor/genéticaRESUMEN
Chronic hepatitis B (HBV) and C (HCV) virus infections are the most important factors associated with hepatocellular carcinoma (HCC), but tumor prognosis remains poor due to the lack of diagnostic biomarkers. In order to identify novel diagnostic markers and therapeutic targets, the gene expression profile associated with viral and non-viral HCC was assessed in 9 tumor samples by oligo-microarrays. The differentially expressed genes were examined using a z-score and KEGG pathway for the search of ontological biological processes. We selected a non-redundant set of 15 genes with the lowest P value for clustering samples into three groups using the non-supervised algorithm k-means. Fisher's linear discriminant analysis was then applied in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Different transcriptional levels of genes were identified in HCC of different etiologies and from different HCC samples. When comparing HBV-HCC vs HCV-HCC, HBV-HCC/HCV-HCC vs non-viral (NV)-HCC, HBC-HCC vs NV-HCC, and HCV-HCC vs NV-HCC of the 58 non-redundant differentially expressed genes, only 6 genes (IKBKbeta, CREBBP, WNT10B, PRDX6, ITGAV, and IFNAR1) were found to be associated with hepatic carcinogenesis. By combining trios, classifiers could be generated, which correctly classified 100% of the samples. This expression profiling may provide a useful tool for research into the pathophysiology of HCC. A detailed understanding of how these distinct genes are involved in molecular pathways is of fundamental importance to the development of effective HCC chemoprevention and treatment.
Asunto(s)
Carcinoma Hepatocelular/genética , Perfilación de la Expresión Génica , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Neoplasias Hepáticas/genética , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/virología , Etiquetas de Secuencia Expresada , Humanos , Neoplasias Hepáticas/virologíaRESUMEN
Non-alcoholic steatohepatitis (NASH) has been associated with hepatocellular carcinoma (HCC) often arising in histologically advanced disease when steatohepatitis is not active (cryptogenic cirrhosis). Our objective was to characterize patients with HCC and active, histologically defined steatohepatitis. Among 394 patients with HCC detected by ultrasound imaging over 8 years and staged by the Barcelona Clinic Liver Cancer (BCLC) criteria, we identified 7 cases (1.7 percent) with HCC occurring in the setting of active biopsy-proven NASH. All were negative for other liver diseases such as hepatitis C, hepatitis B, autoimmune hepatitis, Wilson disease, and hemochromatosis. The patients (4 males and 3 females, age 63 ± 13 years) were either overweight (4) or obese (3); 57 percent were diabetic and 28.5 percent had dyslipidemia. Cirrhosis was present in 6 of 7 patients, but 1 patient had well-differentiated HCC in the setting of NASH without cirrhosis (fibrosis stage 1) based on repeated liver biopsies, the absence of portal hypertension by clinical and radiographic evaluations and by direct surgical inspection. Among the cirrhotic patients, 71.4 percent were clinically staged as Child A and 14.2 percent as Child B. Tumor size ranged from 1.0 to 5.2 cm and 5 of 7 patients were classified as early stage; 46 percent of all nodules were hyper-echoic and 57 percent were <3 cm. HCC was well differentiated in 1/6 and moderately differentiated in 5/6. Alpha-fetoprotein was <100 ng/mL in all patients. HCC in patients with active steatohepatitis is often multifocal, may precede clinically advanced disease and occurs without diagnostic levels of alpha-fetoprotein. Importantly, HCC may occur in NASH in the absence of cirrhosis. More aggressive screening of NASH patients may be warranted.
Asunto(s)
Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular/complicaciones , Hígado Graso/complicaciones , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Carcinoma Hepatocelular/patología , Hígado Graso/patología , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Estadificación de NeoplasiasRESUMEN
Non-alcoholic steatohepatitis (NASH) has been associated with hepatocellular carcinoma (HCC) often arising in histologically advanced disease when steatohepatitis is not active (cryptogenic cirrhosis). Our objective was to characterize patients with HCC and active, histologically defined steatohepatitis. Among 394 patients with HCC detected by ultrasound imaging over 8 years and staged by the Barcelona Clinic Liver Cancer (BCLC) criteria, we identified 7 cases (1.7%) with HCC occurring in the setting of active biopsy-proven NASH. All were negative for other liver diseases such as hepatitis C, hepatitis B, autoimmune hepatitis, Wilson disease, and hemochromatosis. The patients (4 males and 3 females, age 63 +/- 13 years) were either overweight (4) or obese (3); 57% were diabetic and 28.5% had dyslipidemia. Cirrhosis was present in 6 of 7 patients, but 1 patient had well-differentiated HCC in the setting of NASH without cirrhosis (fibrosis stage 1) based on repeated liver biopsies, the absence of portal hypertension by clinical and radiographic evaluations and by direct surgical inspection. Among the cirrhotic patients, 71.4% were clinically staged as Child A and 14.2% as Child B. Tumor size ranged from 1.0 to 5.2 cm and 5 of 7 patients were classified as early stage; 46% of all nodules were hyper-echoic and 57% were <3 cm. HCC was well differentiated in 1/6 and moderately differentiated in 5/6. Alpha-fetoprotein was <100 ng/mL in all patients. HCC in patients with active steatohepatitis is often multifocal, may precede clinically advanced disease and occurs without diagnostic levels of alpha-fetoprotein. Importantly, HCC may occur in NASH in the absence of cirrhosis. More aggressive screening of NASH patients may be warranted.
Asunto(s)
Carcinoma Hepatocelular/complicaciones , Hígado Graso/complicaciones , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Adulto , Anciano , Carcinoma Hepatocelular/patología , Hígado Graso/patología , Femenino , Humanos , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estadificación de NeoplasiasRESUMEN
AIMS: Annexin A1 (ANXA1) is a soluble cytoplasmic protein, moving to membranes when calcium levels are elevated. ANXA1 has also been shown to move to the nucleus or outside the cells, depending on tyrosine-kinase signalling, thus interfering in cytoskeletal organization and cell differentiation, mostly in inflammatory and neoplastic processes. The aim was to investigate subcellular patterns of immunohistochemical expression of ANXA1 in neoplastic and non-neoplastic samples from patients with laryngeal squamous cell carcinomas (LSCC), to elucidate the role of ANXA1 in laryngeal carcinogenesis. METHODS AND RESULTS: Serial analysis of gene expression experiments detected reduced expression of ANXA1 gene in LSCC compared with the corresponding non-neoplastic margins. Quantitative polymerase chain reaction confirmed ANXA1 low expression in 15 LSCC and eight matched normal samples. Thus, we investigated subcellular patterns of immunohistochemical expression of ANXA1 in 241 paraffin-embedded samples from 95 patients with LSCC. The results showed ANXA1 down-regulation in dysplastic, tumourous and metastatic lesions and provided evidence for the progressive migration of ANXA1 from the nucleus towards the membrane during laryngeal tumorigenesis. CONCLUSIONS: ANXA1 dysregulation was observed early in laryngeal carcinogenesis, in intra-epithelial neoplasms; it was not found related to prognostic parameters, such as nodal metastases.
Asunto(s)
Anexina A1/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anexina A1/análisis , Anexina A1/genética , Western Blotting , Carcinoma de Células Escamosas/patología , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana EdadRESUMEN
Occult hepatitis B virus (HBV) infection has been reported among patients with hepatitis C virus (HCV) infection and hepatocellular carcinoma (HCC). Our aim was to evaluate the presence of occult HBV infection in patients with HCV-related liver cirrhosis (LC) with or without HCC in São Paulo, Brazil. Serum and liver tissue samples from 50 hepatitis B surface antigen-negative patients with HCV-related LC who underwent liver transplantation at the University of São Paulo School of Medicine Hospital from 1993 to 2004 were divided into groups with LC only (N = 33) and with LC plus HCC (N = 17). HBV DNA was assayed for serum and paraffin-embedded liver tissue (tumoral and non-tumoral) using real time PCR and only 1 case with HCC had HBV DNA-positive serum. All liver samples were negative. HCV genotype 3 was detected in 17/39 (43.7 percent) cases. In conclusion, using a sensitive real time PCR directed to detect HBV variants circulating in Brazil, occult hepatitis B infection was not found among HCV-positive cirrhotic patients and was rarely found among HCV-positive HCC patients. These results are probably related to the low prevalence of HBV infection in our population. Furthermore, we have also shown that HCV genotype 3 is frequently found in Brazilian cirrhotic patients, particularly when they also have HCC. More studies involving a large number of cases should be carried out to confirm these data and to further characterize Brazilian HCV genotype isolates to elucidate genetic features that might be related to its carcinogenic potential.
Asunto(s)
Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Hepatocelular/virología , Hepatitis B/diagnóstico , Hepatitis C/complicaciones , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Brasil/epidemiología , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B/epidemiología , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/epidemiologíaRESUMEN
Occult hepatitis B virus (HBV) infection has been reported among patients with hepatitis C virus (HCV) infection and hepatocellular carcinoma (HCC). Our aim was to evaluate the presence of occult HBV infection in patients with HCV-related liver cirrhosis (LC) with or without HCC in São Paulo, Brazil. Serum and liver tissue samples from 50 hepatitis B surface antigen-negative patients with HCV-related LC who underwent liver transplantation at the University of São Paulo School of Medicine Hospital from 1993 to 2004 were divided into groups with LC only (N = 33) and with LC plus HCC (N = 17). HBV DNA was assayed for serum and paraffin-embedded liver tissue (tumoral and non-tumoral) using real time PCR and only 1 case with HCC had HBV DNA-positive serum. All liver samples were negative. HCV genotype 3 was detected in 17/39 (43.7%) cases. In conclusion, using a sensitive real time PCR directed to detect HBV variants circulating in Brazil, occult hepatitis B infection was not found among HCV-positive cirrhotic patients and was rarely found among HCV-positive HCC patients. These results are probably related to the low prevalence of HBV infection in our population. Furthermore, we have also shown that HCV genotype 3 is frequently found in Brazilian cirrhotic patients, particularly when they also have HCC. More studies involving a large number of cases should be carried out to confirm these data and to further characterize Brazilian HCV genotype isolates to elucidate genetic features that might be related to its carcinogenic potential.
Asunto(s)
Carcinoma Hepatocelular/virología , Hepatitis B/diagnóstico , Hepatitis C/complicaciones , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Anciano , Brasil/epidemiología , Femenino , Genotipo , Hepacivirus/genética , Hepacivirus/inmunología , Hepatitis B/epidemiología , Anticuerpos contra la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis C/epidemiología , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A morphological evaluation of histopathological liver samples from 42 fulminant hepatic failure cases from the Amazon Basin was undertaken in order to differentiate yellow fever (YF) from Lábrea hepatitis (LH) and other entities. The pattern and distribution of liver cell death as well as ballooning degeneration and midzonal apoptotic bodies were the most distinctive features of YF, whereas morula cells were the major finding for LH. Nineteen well characterised cases were further submitted to immunohistochemical studies for expression of YF antigen, hepatitis B surface antigen (HBsAg) and delta virus antigen. In both diseases, but particularly in LH, portal vein branch phlebitis was evident and might have played a role in the pathogenesis of hepatic injury, leading to hepatic extinction and portal tract approximation. The regeneration pattern was remarkable: a high proliferative index was detected in YF, whereas in LH multinucleation and pseudoacinar transformation, associated with portal type I collagen deposition and portal elastic fibre proliferation, was seen. In conclusion, midzonal apoptosis, portal phlebitis and a high proliferative index in patients without evidence of previous liver injury was the dominant picture in YF. On the other hand, LH cases showed extensive, predominantly lytic hepatocytic necrosis, portal and hepatic vein phlebitis and morula cells in patients with a morphological background of chronic liver disease.
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Hepatitis Viral Humana/patología , Fallo Hepático Agudo/patología , Hígado/patología , Fiebre Amarilla/patología , Adolescente , Adulto , Brasil , Niño , Preescolar , Femenino , Hepatitis Viral Humana/inmunología , Humanos , Lactante , Fallo Hepático Agudo/metabolismo , Masculino , Fiebre Amarilla/inmunologíaRESUMEN
OBJECTIVE: To evaluate the performance of a new, manual, simplified liquid-based system, DNA-Citoliq (Digene Brasil), employed under routine conditions as compared to conventional smears collected from six collaborating private laboratories. METHODS: A panel of cytopathologists, who served as the gold standard diagnosis, adjudicated discordant opinions. RESULTS: Of 3206 pairs of slides considered valid for comparison, there were 3008 in full agreement (93.8%), 112 (3.5%) with one diagnostic category discrepancies, and 86 (2.7%) discordant cases. Among the 288 borderline+ by either method, DNA-Citoliq detected abnormalities in 243 (84.4%), and conventional smears (CS) detected abnormalities in 178 (61.8%) (McNemar test, P < 0.000), a 36.5% increased detection of borderline+ cases. CONCLUSIONS: For mild dyskaryosis, DNA-Citoliq detected 176 cases and CS 125 cases (McNemar test, P < 0.000); and for moderate+severe dyskaryosis 66 versus 32 cases respectively (McNemar test, P < 0.000).
Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Citodiagnóstico/métodos , Enfermedades del Cuello del Útero/diagnóstico , Frotis Vaginal/métodos , Carcinoma de Células Escamosas/patología , Eficiencia , Femenino , Humanos , Valor Predictivo de las Pruebas , Sensibilidad y EspecificidadRESUMEN
An in situ hybridization (ISH) assay for the detection of leptospiral DNA in tissues was described and its diagnostic and pathogenetic usefulness in combination with immunohistochemistry (IHC) was evaluated in formalin-fixed, paraffin-embedded liver and kidney samples from human fatal cases of leptospirosis. IHC assays with anti-E-cadherin antibodies assessed the liver-plate disarray frequently observed in leptospirosis. Immunohistochemistry detected leptospiral antigen (LAg) in macrophages, both in human liver and kidney. In guinea pigs, in addition to these findings, staining on cell membranes of hepatocytes and, occasionally, in apical membrane of kidney tubular cells was demonstrated. Positive ISH signal was observed chiefly in the nuclei of human hepatocytes and in the cytoplasm and nuclei of liver cells of experimentally infected guinea pigs. Loss of E-cadherin membrane expression is associated with liver-plate disarray. These findings were discussed in the contention that, in leptospirosis, cell membrane damage might be important for the pathogenesis of the disease. Finally, it was suggested that both IHC and/or ISH might be used for both diagnostic and research purposes.
Asunto(s)
ADN Bacteriano/aislamiento & purificación , Hibridación in Situ/métodos , Riñón/microbiología , Leptospirosis/diagnóstico , Leptospirosis/metabolismo , Hígado/microbiología , Adulto , Animales , Cadherinas/metabolismo , Membrana Celular/metabolismo , Membrana Celular/patología , Femenino , Cobayas , Humanos , Inmunohistoquímica , Riñón/metabolismo , Riñón/patología , Leptospirosis/patología , Hígado/metabolismo , Hígado/patología , Masculino , Persona de Mediana EdadRESUMEN
Oxidative stress and hepatic mitochondria play a role in the pathogenesis of nonalcoholic fatty liver disease. The aim of the present study was to evaluate the role of hepatic mitochondrial dysfunction and oxidative stress in the pathogenesis of the disease. Fatty liver was induced in Wistar rats with a choline-deficient diet (CD; N = 7) or a high-fat diet enriched with PUFAs-omega-3 (H; N = 7) for 4 weeks. The control group (N = 7) was fed a standard diet. Liver mitochondrial oxidation and phosphorylation were measured polarographically and oxidative stress was estimated on the basis of malondialdehyde and glutathione concentrations. Moderate macrovacuolar liver steatosis was observed in the CD group and mild liver steatosis was observed in the periportal area in the H group. There was an increase in the oxygen consumption rate by liver mitochondria in respiratory state 4 (S4) and a decrease in respiratory control rate (RCR) in the CD group (S4: 32.70 +/- 3.35; RCR: 2.55 +/- 0.15 ng atoms of O2 min-1 mg protein-1) when compared to the H and control groups (S4: 23.09 +/- 1.53, 17.04 +/- 2.03, RCR: 3.15 +/- 0.15, 3.68 +/- 0.15 ng atoms of O2 min-1 mg protein-1, respectively), P < 0.05. Hepatic lipoperoxide concentrations were significantly increased and the concentration of reduced glutathione was significantly reduced in the CD group. A choline-deficient diet causes moderate steatosis with disruption of liver mitochondrial function and increased oxidative stress. These data suggest that lipid peroxidation products can impair the flow of electrons along the respiratory chain, causing overreduction of respiratory chain components and enhanced mitochondrial reactive oxygen species. These findings are important in the pathogenesis of nonalcoholic fatty liver disease.
Asunto(s)
Hígado Graso/etiología , Mitocondrias Hepáticas/fisiología , Enfermedades Mitocondriales/complicaciones , Estrés Oxidativo/fisiología , Animales , Deficiencia de Colina/complicaciones , Modelos Animales de Enfermedad , Ácidos Grasos Omega-3/administración & dosificación , Hígado Graso/metabolismo , Masculino , Mitocondrias Hepáticas/metabolismo , Fosforilación , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno , Índice de Severidad de la EnfermedadRESUMEN
Oxidative stress and hepatic mitochondria play a role in the pathogenesis of nonalcoholic fatty liver disease. The aim of the present study was to evaluate the role of hepatic mitochondrial dysfunction and oxidative stress in the pathogenesis of the disease. Fatty liver was induced in Wistar rats with a choline-deficient diet (CD; N = 7) or a high-fat diet enriched with PUFAs-omega-3 (H; N = 7) for 4 weeks. The control group (N = 7) was fed a standard diet. Liver mitochondrial oxidation and phosphorylation were measured polarographically and oxidative stress was estimated on the basis of malondialdehyde and glutathione concentrations. Moderate macrovacuolar liver steatosis was observed in the CD group and mild liver steatosis was observed in the periportal area in the H group. There was an increase in the oxygen consumption rate by liver mitochondria in respiratory state 4 (S4) and a decrease in respiratory control rate (RCR) in the CD group (S4: 32.70 ± 3.35; RCR: 2.55 ± 0.15 ng atoms of O2 min-1 mg protein-1) when compared to the H and control groups (S4: 23.09 ± 1.53, 17.04 ± 2.03, RCR: 3.15 ± 0.15, 3.68 ± 0.15 ng atoms of O2 min-1 mg protein-1, respectively), P < 0.05. Hepatic lipoperoxide concentrations were significantly increased and the concentration of reduced glutathione was significantly reduced in the CD group. A choline-deficient diet causes moderate steatosis with disruption of liver mitochondrial function and increased oxidative stress. These data suggest that lipid peroxidation products can impair the flow of electrons along the respiratory chain, causing overreduction of respiratory chain components and enhanced mitochondrial reactive oxygen species. These findings are important in the pathogenesis of nonalcoholic fatty liver disease.
Asunto(s)
Animales , Masculino , Ratas , Hígado Graso/etiología , Mitocondrias Hepáticas/fisiología , Enfermedades Mitocondriales/complicaciones , Estrés Oxidativo/fisiología , Deficiencia de Colina/complicaciones , Modelos Animales de Enfermedad , /administración & dosificación , Hígado Graso/metabolismo , Mitocondrias Hepáticas/metabolismo , Fosforilación , Ratas Wistar , Especies Reactivas de Oxígeno , Índice de Severidad de la EnfermedadRESUMEN
The purpose of the present study was to determine the frequency of hepatitis B virus (HBV) markers in families of HBsAg-positive patients with chronic liver disease. Serum anti-HBc, HBsAg and anti-HBs were determined by enzyme immunoassay and four subpopulations were considered: genetically related (consanguineous) and non-genetically related (non-consanguineous) Asian subjects and genetically related and non-genetically related Western subjects. A total of 165 and 186 relatives of Asian and Western origin were enrolled, respectively. The occurrence of HBsAg and anti-HBs antibodies was significantly higher (P < 0.0001) in family members of Asian origin (81.8%) than in family members of Western origin (36.5%). HBsAg was also more frequent among brothers (79.6 vs 8.5%; P < 0.0001), children (37.9 vs 3.3%; P < 0.0001) and other family members (33.9 vs 16.7%; P < 0.0007) of Asian than Western origin, respectively. No difference between groups was found for anti-HBs, which was more frequently observed in fathers, spouses and other non-genetic relatives. HBV infection was significantly higher in children of Asian than Western mothers (P < 0.0004). In both ethnic groups, the mothers contributed more to their children's infection than the fathers (P < 0.0001). Furthermore, HBsAg was more frequent among consanguineous members and anti-HBs among non-consanguineous members. These results suggest the occurrence of vertical transmission of HBV among consanguineous members and probably horizontal sexual transmission among non-consanguineous members of a family cluster. Thus, the high occurrence of dissemination of HBV infection characterizes family members as a high-risk group that calls for immunoprophylaxis. Finally, the study showed a high familial aggregation rate for both ethnic groups, 18/19 (94.7%) and 23/26 (88.5%) of the Asian and Western origin, respectively.
Asunto(s)
Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/etnología , Adolescente , Adulto , Pueblo Asiatico , Biomarcadores/sangre , Brasil/etnología , Niño , Familia , Femenino , Hepatitis B Crónica/sangre , Hepatitis B Crónica/transmisión , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Población BlancaRESUMEN
The purpose of the present study was to determine the frequency of hepatitis B virus (HBV) markers in families of HBsAg-positive patients with chronic liver disease. Serum anti-HBc, HBsAg and anti-HBs were determined by enzyme immunoassay and four subpopulations were considered: genetically related (consanguineous) and non-genetically related (non-consanguineous) Asian subjects and genetically related and non-genetically related Western subjects. A total of 165 and 186 relatives of Asian and Western origin were enrolled, respectively. The occurrence of HBsAg and anti-HBs antibodies was significantly higher (P < 0.0001) in family members of Asian origin (81.8 percent) than in family members of Western origin (36.5 percent). HBsAg was also more frequent among brothers (79.6 vs 8.5 percent; P < 0.0001), children (37.9 vs 3.3 percent; P < 0.0001) and other family members (33.9 vs 16.7 percent; P < 0.0007) of Asian than Western origin, respectivelly. No difference between groups was found for anti-HBs, which was more frequently observed in fathers, spouses and other non-genetic relatives. HBV infection was significantly higher in children of Asian than Western mothers (P < 0.0004). In both ethnic groups, the mothers contributed more to their children's infection than the fathers (P < 0.0001). Furthermore, HBsAg was more frequent among consanguineous members and anti-HBs among non-consanguineous members. These results suggest the occurrence of vertical transmission of HBV among consanguineous members and probably horizontal sexual transmission among non-consanguineous members of a family cluster. Thus, the high occurrence of dissemination of HBV infection characterizes family members as a high-risk group that calls for immunoprophylaxis. Finally, the study showed a high familial aggregation rate for both ethnic groups, 18/19 (94.7 percent) and 23/26 (88.5 percent) of the Asian and Western origin, respectively.
Asunto(s)
Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/etnología , Pueblo Asiatico , Biomarcadores/sangre , Brasil/etnología , Población Blanca , Familia , Hepatitis B Crónica/sangre , Hepatitis B Crónica/transmisión , Técnicas para Inmunoenzimas , Estudios ProspectivosRESUMEN
AIMS: To assess potential alterations of the nasal mucosa by clinical and histopathological evaluation of workers exposed to sulphuric acid mists at anodising plants, correlating the findings with duration of exposure and sulphuric acid concentrations in the air, and comparing them with a control group. METHODS: Fifty two workers from five plants underwent a clinical evaluation (standard questionnaire, clinical, and ear, nose, and throat examination including nasal endoscopy). For the histopathological study, 20 of the 52 subjects (study group) were randomly selected, as well as 11 unexposed subjects (control group), matched by sex, age, and smoking habits. Nasal biopsy specimens were obtained from the anterior septum mucosa and the anterior curvature of the middle turbinate in each individual. A total of 56 nasal mucosa specimens (37 in the study group and 19 in the control group) were evaluated with regard to normal respiratory epithelium or metaplastic epithelium, atypia or dysplasia, and alterations of the lamina propria. RESULTS: The histopathological study revealed squamous metaplasia in 29 (79%) and atypia in 13 (35%) of the 37 study group samples. No association was found between exposure duration and the clinical and histopathological variables, but a significant association was found between sulphuric acid concentrations higher than 200 micro g/m(3) and pale mucosal patches and ulcerations in the exposed subjects. Logistic regression analysis showed that the exposed subjects had a fivefold risk of developing atypia compared with the unexposed subjects. CONCLUSIONS: Workers exposed to sulphuric acid mists presented with a high incidence of nasal symptoms, and macroscopic and microscopic changes of the nasal mucosa, including squamous atypia and dysplasia. The risk for these histopthological lesions increased with higher sulphuric acid concentrations in the air, revealing an exposure-response relation.
Asunto(s)
Contaminantes Ocupacionales del Aire/efectos adversos , Mucosa Nasal/efectos de los fármacos , Enfermedades Nasales/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Ácidos Sulfúricos/efectos adversos , Adulto , Biopsia , Brasil , Estudios Transversales , Humanos , Masculino , Metalurgia , Persona de Mediana Edad , Mucosa Nasal/patología , Enfermedades Nasales/patología , Enfermedades Profesionales/patología , Análisis de RegresiónRESUMEN
Mutations of the tumor suppressor gene p53 have been considered to be important determinants in several kinds of human cancer. Accumulation of p53 protein has been reported to correlate with more aggressive clinical behavior in some neoplasms. The role of p53 expression in adrenal cortical tumors (ACT) has not been elucidated but some studies have suggested its correlation with malignant behavior. Our objective was to determine if there is a correlation between the expression of immunoreactive p53 and the biological behavior of ACT. Fifty-seven ACT (21 from children and 36 from adults) were evaluated for p53 expression by immunohistochemistry in formalin-fixed paraffin-embedded tissue and analyzed in terms of outcome. The p53 parameter was utilized semiquantitatively. Tumors were classified as p53 negative when no positivity was observed, or when only few cells showed weak positivity (0/1+) and scored as p53 positive when there was a diffuse and strong nuclear positivity (2+/3+). In children, p53 positivity was associated with clinically malignant ACT and p53 negativity was associated with clinically benign ACT (P = 0.026). In adults' ACT, p53 positivity had an effect on disease-free survival (P<0.001) and also correlated with Weiss score, with a cutoff = 4 (P = 0.04). p53 expression was related to the clinical behavior of ACT in both children and adults and these findings seem to support a role for p53 in ACT progression.
Asunto(s)
Neoplasias de la Corteza Suprarrenal/genética , Biomarcadores de Tumor/genética , Genes p53/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Neoplasias de la Corteza Suprarrenal/patología , Adulto , Biomarcadores de Tumor/análisis , Niño , Supervivencia sin Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Mutación , Pronóstico , Proteína p53 Supresora de Tumor/análisisRESUMEN
Mutations of the tumor suppressor gene p53 have been considered to be important determinants in several kinds of human cancer. Accumulation of p53 protein has been reported to correlate with more aggressive clinical behavior in some neoplasms. The role of p53 expression in adrenal cortical tumors (ACT) has not been elucidated but some studies have suggested its correlation with malignant behavior. Our objective was to determine if there is a correlation between the expression of immunoreactive p53 and the biological behavior of ACT. Fifty-seven ACT (21 from children and 36 from adults) were evaluated for p53 expression by immunohistochemistry in formalin-fixed paraffin-embedded tissue and analyzed in terms of outcome. The p53 parameter was utilized semiquantitatively. Tumors were classified as p53 negative when no positivity was observed, or when only few cells showed weak positivity (0/1+) and scored as p53 positive when there was a diffuse and strong nuclear positivity (2+/3+). In children, p53 positivity was associated with clinically malignant ACT and p53 negativity was associated with clinically benign ACT (P = 0.026). In adults' ACT, p53 positivity had an effect on disease-free survival (P<0.001) and also correlated with Weiss score, with a cutoff = 4 (P = 0.04). p53 expression was related to the clinical behavior of ACT in both children and adults and these findings seem to support a role for p53 in ACT progression