Study of major genetic factors involved in pituitary tumorigenesis and their impact on clinical and biological characteristics of sporadic somatotropinomas and non-functioning pituitary adenomas

Genetic and functional aberrations of guanine nucleotide-binding protein, alpha stimulating (GNAS), aryl hydrocarbon receptor interacting protein (AIP), and pituitary tumor transforming gene (PTTG) are among the most prominent events in pituitary tumorigenesis. A cohort of Brazilian patients with somatotropinomas (n=41) and non-functioning pituitary adenomas (NFPA, n=21) from a single tertiary-referral center were evaluated for GNAS and AIP mutations and gene expression of AIP and PTTG. Results were compared to the clinical and biological (Ki67 and p53 expression) characteristics of tumors and their response to therapy, if applicable. Genetic analysis revealed that 27% of somatotropinomas and 4.8% of NFPA harbored GNAS mutations (P=0.05). However, no differences were observed in clinical characteristics, tumor extension, response to somatostatin analog therapy, hormonal/surgical remission rates, Ki67 index, and p53 expression between mutated and non-mutated somatotropinomas patients. PTTG overexpression (RQ mean=10.6, min=4.39, max=11.9) and AIP underexpression (RQ mean=0.56, min=0.46-max=0.92) were found in virtually all cases without a statistically significant relationship with clinical and biological tumor features. No patients exhibited somatic or germline pathogenic AIP mutations. In conclusion, mutations in GNAS and abnormal PTTG and AIP expression had no impact on tumor features and treatment outcomes in this cohort. Our data support some previous studies and point to the need for further investigations, probably involving epigenetic and transcriptome analysis, to improve our understanding of pituitary tumor behavior.

Differential gene expression profiles of hepatocellular carcinomas associated or not with viral infection

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 (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.

Does hepatocellular carcinoma in non-alcoholic steatohepatitis exist in cirrhotic and non-cirrhotic patients?

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.

Low occurrence of occult hepatitis B virus infection and high frequency of hepatitis C virus genotype 3 in hepatocellular carcinoma in Brazil

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.

Liver mitochondrial dysfunction and oxidative stress in the pathogenesis of experimental nonalcoholic fatty liver disease

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.

A prospective study of hepatitis B virus markers in patients with chronic HBV infection from Brazilian families of Western and Asian origin

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.

p53 as a prognostic factor in adrenocortical tumors of adults and children

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

Detection of human parvovirus B19 in a patient with hepatitis

Parvovirus B19 has been associated by some investigators with cases of severe hepatitis. The aim of the present study was to determine the presence of active parvovirus B19 infection among 129 Brazilian patients with non-A-E hepatitis. The patients were assayed for antibodies against parvovirus B19, IgM class, by ELISA. In IgM-positive cases, parvovirus B19 DNA was assayed by PCR in serum and liver tissue and parvovirus VP1 antigen in liver tissue was assayed by immunohistochemistry. Antibodies against parvovirus B19, IgM class, were detected in 3 (2.3 percent) of 129 patients with non-A-E hepatitis. Previous surgery and blood transfusions were reported by these 3 patients. One patient was a 56-year-old female with severe hepatitis, with antimitochondrial antibody seropositivity and submassive necrosis at liver biopsy, who responded to corticosteroid therapy. Strong evidence for active parvovirus B19 infection was found in this patient, with parvovirus B19 DNA being detected by PCR in liver tissue. Furthermore, parvovirus VP1 antigen was also detected in liver tissue by immunohistochemistry. The other two IgM-positive patients were chronic hepatitis cases, but active infection was not proven, since neither viral DNA nor antigen were detected in their liver tissues. This and other reports suggest a possible relation between parvovirus B19 infection and some cases of hepatitis

Frequência de adenocarcinomas em derrames cavitários / Frequency of adenocarcinomas in serious effusions

Objetivo. Identificação de freqüência de adenocarcinomas de diferentes sítios primários em derrames cavitários. Material e Métodos. Foram estudados 2.317 casos: 1.146 de derrame pleural (943 mulheres e 203 homens), 1.168 de ascite (727 mulheres e 441 homens) e três pericárdio (duas mulheres e um homem) e realizada análise retrospectiva dos prontuários dos pacientes e correlação dos achados clínico-laboratoriais. Resultados. Os sítios primários mais freqüentes em derrames pleurais foram: mama (N=586 - 51,1 por cento), pulmão (N=185 - 16,1 por cento: 102 homens e 83 mulheres), ovário (N=124 - 10,8 por cento); em ascites: estômago (N=473 - 40,5 por cento: 300 homens e 173 mulheres), ovário (N=306 - 26,2 por cento) e mama (N=83 - 7,1 por cento). Desses, 555 casos foram citologicamente positivos para malignidade em derrames pleurais, 541 em ascite e dois em pericárdio. Os sítios primários mais freqüentes em derrames pleurais citologicamente positivos foram: mama (N=288 - 51,9 por cento), pulmão (N=92, 16,6 por cento: 45 homens e 47 mulheres) e ovário (N=54, 9,7 por cento); e, em ascites: ovário (N=205 - 37,9 por cento), estômago (N=202, 37,3 por cento: 119 homens e 83 mulheres) e mama (N=31 - 6,8 por cento). Em 47 derrames pleurais (8,5 por cento) e 37 ascites (6,8 por cento), a origem dos adenocarcinomas persistiu indeterminada. Conclusão. As freqüências estabelecidas poderão, em associação e dados clínicos, orientar a investigação dos sítios primários de adenocarcinomas metastáticos.

Tumores neuro-endocrinos do estomago e duodeno: estudo morfologico e imunohistoquimico das suas diferentes formas de apresentacao clinico-patologicas / Neuroendocrine tumors of the stomach and duodenum: a morphologic and imunohistochemical study of the different clinical and pathological presentations

Apos o advento da endoscopia digestiva alta, o numero de casos diagnosticados com tumores neuroendocrinos (TNE) gastricos e duodenais tem aumentado consideravelmente. Novas classificacoes tem sido propostas, entretanto ha escassez de conhecimento em nosso meio, motivando o presente estudo...

Estudo anatomopatológico e imuno-histoquímico de carcinoma renal metastático em um bovino / Anatomopathological and immunohistochemical studies of metastatic renal carcinoma in a cow

O presente relato descreve um caso de carcinoma renal metastático em uma vaca mestiça de seis anos de idade com histórico de emagrecimento progressivo, tosse e dificuldade de locomoçäo. Ao exame clínico, foram observados cifose, secreçäo catarral nas narinas e estertores à auscultaçäo pulmonar. A palpaçäo retal foi detectada uma grande massa de consistência firme, caudal ao rim direito. A laparotomia paralombar direita confirmou a presença dessa massa no pólo caudal do rim direito. Devido a impossibilidade da exérese, optou-se pela eutanásia. A necropsia, observou-se uma massa de 50cm de diâmetro, de aproximadamente quatro quilogramas, com superfície lisa, bem vascularizada de consistência firme, coloraçäo esbranquiçada, que rangia ao corte e apresentava-se aderida às alças do intestino grosso. Os linfonodos mediastinais e alguns linfonodos mesentéricos apresentavam-se aumentados de volume, de consistência firme e esbranquiçados e os pulmöes apresentavam nódulos de tamanhos variados e com características similares àquelas da massa renal. Histologicamente, a neoplasia apresentava características de carcinoma de padräo tubular. Pela imuno-histoquímica foi detectada positividade para os seguintes marcadores tumorais: vimentina (V-9), cytokeratin-7, CD68, 35betaH11, CEA poli e RCC ("renal cell carcinoma"), confirmando a origem renal do processo neoplásico

Garantia de qualidade em citopatologia: aspectos da correlaçäo cito-histopatológica / Quality assurance in cytopathology: aspects of the cytohistological correlation

Os autores avaliaram a concordância diagnóstica cito-histológica de lesöes de colo uterino e discutiram as eventuais discrepâncias. OBJETIVO. Averiguar o nível de concordância cito-histológica nos casos da Divisäo de Patologia do Instituto Adolfo Lutz (IAL) e aprimorar a estratégia de garantia de qualidade na instituiçäo. MATERIAL E MÉTODO. Estudaram 157 casos consecutivos dos arquivos do IAL em que foram enviadas citologia cérvico-vaginal e biópsia. RESULTADO. Houve concordância absoluta em 119 (75,8 por cento) casos; nos demais, a citologia superestimou 11 lesöes (7,0 por cento) e subestimou 27 (17,2 por cento). Observou-se que em 5 casos, inicialmente diagnosticados como inflamatório pela citologia, dois foram, à revisäo, considerados como NIC 1; os demais foram ratificados como inflamatórios, apesar de suas respectivas biópsias terem diagnóstico de neoplasia intra-epitelial cervical. CONCLUSÄO. Tais resultados demonstram a importância da correlaçäo cito-histológica para o sistema de garantia de qualidade em diagnóstico citológico e apontam para a colheita como um dos fatores determinantes nas discrepâncias diagnósticas.

Use of monoclonal antibodies against human T cells for clinical diagnosis by immunohistochemical procedures

Monoclonal antibodies (Mabs) were produced against human T cell membrane antigens. Sixteen Mabs were studied and six were selected for immunohistochemical assays on parffin-embedded tonsil section. Two Mabs (2D7 and 1E2) specifically recognized T-lymphocyte areas in sections of pathological tissues originating from lymphoproliferative diseases, and reacted with proteins of approximately 80 KDa. Most of the Mabs produced thus far are only suitable for immunohistochemical assays on frozen section. Only a few Mabs recognize lymphoid markers on paraffin-embedded sections, a procedure which permits a more extensive and practical application of Mabs in clinical diagnosis. These antibodies should be baluable in diagnosing. T. cell-related diseases and their large scale production should reduce laboratory costs because all reahgents currently avaliable are imported

Amiloidose e plasmocitoma secretor de cadeia leve lambda: / Amyloidosis and light lambda chain secreting plasmacytoma

Apresenta-se o estudo de um caso de amiloidose de multiplas visceras, sem evidencias clinicas, radiologicas e laboratoriais de associacao a outras entidades, levando a obito devido ao macico acometimento cardiaco. A autopsia todavia, revelou plasmocitoma em oitavo arco costal direito, caracterizado a imuno-histoquimica (metodo PAP de imunoperoxidase) como secretor de cadeia leve lambda. Os autores, baseados nesta analise, sugerem que nos casos de amiloidose sem sinais de outras molestias associadas, sejam realizadas biopsias de medula ossea, eventualmente em varias localizacoes, e que, em todas as proliferacoes plasmocitarias sejam aplicados metodos imuno-histoquimicos para pesquisa de cadeias leves e pesadas de imunoglobulinas, favorecendo a diferenciacao de proliferacoes reacionais (policlonais) das neoplasicas (monoclonais)

Identificacao da origem de metastases de carcinoma da tiroide atraves do metodo da imunoperoxidase. / Identification of the origin of metastatic carcinoma by immunoperoxidase method

Muitas vezes e dificil caracterizar a origem tiroidea a partir de tumores metastaticos. Os autores apresentam tres casos de carcinoma de tiroide com deteccao de tiroglobulina em biopsias de metastases pelvicas (casos 1 e 2) e ganglios mediastinais e supraclaviculares (caso 3) mediante imunoperoxidase. Este metodo demonstrou ser de grande utilidade na indicacao da origem tiroidea das metastases, principalmente no caso 1, no qual a metastase folicular apresentava aspecto semelhante a sarcoma alveolar de partes moles, e no caso 3, no qual a palpacao da tiroide, a cintilografia e a tiroglobulina serica foram normai

Activity of chronic hepatitis correlation of clinical, biochemical and histological parameters in 32 cases.

Os Autores estudaram 32 casos de hepatites cronicas com diversos graus de atividade clinica, bioquimica e histologica. A etiologia foi predominantemente viral. Quinze parametros histologicos foram semiquantificados, pesquisando-se posteriormente, correlacao entre os graus obtidos e os valores sericos de ALT, AST, Gama-GT, bilirrubina total e gamaglobulina. Dos parametros histologicos, a proliferacao de ductos biliares e os plasmocitos nao se mostraram uteis para esta analise. Os niveis de bilirrubina total apresentam correlacao estatisticamente significante com 11 variaveis histologicas. Ambas as aminotransferases (ALT e AST) correlacionaram-se com a impressao geral de atividade histologica, sendo que a AST tambem se correlacionou com o grau de expansao portal e de necrose "em saco bocados". A ausencia de correlacoes significantes com gamaglobulina pode se dever a inclusao, neste estudo, de casos de hepatite cronica persistente e a ausencia de hepatites cronicas autoimunes

Tumores germinativos dos testiculos. / Germ cell tumors of the testis

Os autores analisam 21 casos de tumores de celulas germinativas dos testiculos, com relacao aos dados clinicos e anatomopatologicos dos tumores primarios e metastases Dao especial destaque a avaliacao de fatores relacionados a etiologia e efetuam estudo semiquantitativo de caracteristicas histologicas, tais como anaplasia, mitoses, inflamacao, necrose/hemorragia, invasao vascular e invasao do cordao espermatico, alem de registrarem os padroes histologicos das metastases