Qual o valor do índice preditor de resposta terapêutica na quimioterapia neoadjuvante em portadores de carcinoma mamário localmente avançado por cintilografia? / What is the value of the predictive index of therapeutic response in neoadjuvant chemotherapy in patients with locally advanced breast cancer by scintigraphy?

O câncer de mama é o câncer mais comum entre as mulheres, tanto no Brasil quanto no mundo, com 28% dos casos a cada ano sendo novos. O diagnóstico retardado pode identificar o carcinoma de mama localmente avançado (LABC), que requer quimioterapia sistêmica pré-operatória que visa reduzir o tamanho e a carga do tumor. A quimio-resistência pode estar relacionada à expressão da glicoproteína P (GpP) que promove o efluxo celular do medicamento, diminuindo não apenas seu tempo dentro da célula, mas conseqüentemente a apoptose celular. [99mTc]Tc-sestamibi (MIBI), utilizado na realização de cintimografia (SMM), é um substrato destas proteínas, semelhante às drogas quimioterápicas, sendo o único método de imagem a representar o tempo de permanência desta droga. O índice preditivo de resposta quimioterápica da SMM tem sido utilizado para prever o tempo de permanência das drogas quimioterápicas nestas células. Este estudo teve como objetivo verificar se o índice preditivo da resposta quimioterápica neoadjuvante, obtido pela SMM com MIBI proposta por Alonso e colegas, está relacionado à resposta quimioterápica, conforme demonstrado pelo estudo anatomopatológico pós-operatório das mamas (AP), considerado o padrão ouro, analisando os índices isolados, índice precoce (EI) e índice tardio (LI), e índice associado (EI+LI). Este foi um estudo transversal, observacional e descritivo, com dados retrospectivos coletados de quadros de pacientes portadores de LABC atendidos nesta Instituição no período de 2012 a 2017, que foram submetidos à SMM, definindo os valores dos índices de boa resposta isolados ou combinados como EI>1,5 e LI>1,4, quimioterapia neoadjuvante com esquema AC-T e mastectomia posterior ou quadrantectomia, com redução do tamanho do tumor >30% (G>30%) considerada uma boa resposta à PA. O nível de significância foi p<0,05. A amostra foi composta de 151 mulheres com idade média de 54,00 ±10,71 anos (26 a 77 anos, dos quais 72 foram acometidas no lado direito e 79 no lado esquerdo). O tipo histológico predominante foi ductal (n=141; 93,38%), seguido por lobular (n=6; 3,97%), metaplástico (n=2; 1,32%) e papilífero (n=2; 1,32%). A classificação imunohistoquímica evidenciou predominância do tipo luminal B (n=47, 32,41%), seguido pelos tipos triplo-negativo (n=31; 21,38%), HER 2 positivo (n=24; 16,55%), híbrido (n=24; 16,55%), luminal A (n=18; 12,41%) e luminal não-A não-B (n=1; 0,69%). O tamanho inicial dos tumores variou de 0,20 a 16,00 cm, com uma média de 3,40±2,26 cm. O tamanho final do tumor variou de 0,00 a 11,00 cm, com uma média de 1,63±2,01 cm. Em média, a redução percentual do tamanho do tumor foi de 51,72±58,46%, variando de -185,71 a 100%, uma vez que alguns tumores apresentaram uma progressão de tamanho. Não houve associação significativa entre EI versus G>30% (p=0,8054); LI versus G>30% (p=0,2097), e (EI+LI) versus G>30% (p=0,1289). Em conclusão, não existe associação entre os índices preditivos de boa resposta descritos no SMM e a resposta de redução de tamanho observada na AP em transportadoras LABC tratadas com o esquema quimioterápico AC-T

Transcript finishing initiative: contribuição do laboratório IL2

O principal objetivo na análise de um genoma é a identificação gênica. Várias ferramentas computacionais estão disponíveis para este propósito e são baseadas em similaridade (BLAST e BLAT) ou em predição de genes (Genscan e Fgenes). Entretanto, estes programas estão se mostrando ineficientes para detectar e caracterizar todos os genes presentes no genoma humano. A importância das informações de cDNAs tem sido reconhecida desde o início do Projeto Genoma Humano, entretanto, o seqüenciamento em larga escala de cDNAs completos ainda requer técnicas avançadas tais como a produção de bibliotecas de cDNAs enriquecidas por transcritos grandes e raros. O seqüenciamento parcial de etiquetas de seqüências expressas (ESTs) foi desenvolvido como uma técnica alternativa para gerar, em larga escala, vários tipos de cDNAs. Atualmente, a maioria das informações de cDNAs no GenBank são representadas por ESTs convencionais 3þ e 5þ e ORESTES (provenientes das porções centrais dos transcritos). Baseados nos bancos de dados gerados pelo alinhamento de todas essas seqüências com as seqüências genômicas humanas disponíveis foi proposta a estratégia transcript finishing para a caracterização e validação de novos genes humanos, como parte do consórcio entre FAPESP e Instituto Ludwig de Pesquisa sobre o Câncer. O projeto Transcript Finishing Initiative está sendo realizado por uma rede de 31 diferentes grupos de pesquisa do Estado de São Paulo. Foram selecionados pela coordenação do projeto, 602 transcritos e destes 300 (50%) foram validados. Destes transcritos, 20 foram atribuídos ao laboratório validador IL2, e destes, 11 (55%) foram validados. Utilizando ferramentas de bioinformática, o laboratório IL2 realizou uma anotação preliminar dos consensos de seus transcritos validados (disponibilizados pela coordenação do projeto)... .A fundamental task in analyzing genome is gene identification. This is relatively straightforward for compact genome but much more challenging for complex genomes. Some computational tools are available for this purpose, but they are bases on similarity (BLAST) or prediction analysis (Genscan and Fgenes). However, these programs are inefficient to detect and characterize all genes present in the genome. The importance of cDNA information has been recognized since the beginning of the Human Genome Project, however cost-effective and hightroughput sequencing of full-length cDNA still requires technical advances such as the production of cDNA libraries enriched for large and rare transcripts. Partial sequencing of expressed sequences (EST) has been developed as an alternative approach for the generation, in large-scale, of several kinds of cDNAs. Currently, the vast majority of cDNA data in the GenBank is represented both by conventional 5þand 3þexpressed sequence tags (ESTs) and by ORESTES (open reading frame ESTs), which is derived from central portions of the transcripts. Based on a database generated through alignment of all of these sequences to the available human genomic sequences, have been proposed the transcript finishing strategy for characterization and validation of new human genes, as part of the FAPESP-LICR Transcript Finishing Initiative. The strategy utilizes the ORESTES scaffold EST sequence to build primers for reverse transcription (RT) - PCR reactions in order to bridge gaps, thereby confirming the membership of ESTs to a common transcript and providing information on the intervening sequence (validation strategy). The FAPESP-LICR Transcript Finishing Initiative is being pursed by a network of 31 different research groups from the State of São Paulo (The Transcript Finishing Consortium) coordinated by 2 different laboratories... (Complete abstract click electronic address below)

Análise das alterações genéticas e epigenéticas dos tumores gástricos infectados por Helicobacter pylori e v rus Epstein-Barr

Gastric cancer (GC) is one of the most common cancer types and it is associated with high mortality frequencies. Although a decrease in the worldwide incidence is observed, the prognosis of this disease still remains poor, mainly when the diagnosis is carried out at advanced stages. Recent evidences have identified DNA methylation as an important mechanism for tumor suppressor gene inactivation. Helicobacter pylori infection is considered one of the most important etiological factors and the CagA gene is associated with more severe pathologies including cancer. Likewise, EBV is another infectious agent that has been associated with gastric carcinoma in at least 10% of the cases. In this study, we determined the promoter methylation status of the CDH1, DAPK, COX2, hMLH1 and CDKN2A and MSI frequency in 89 primary gastric carcinomas and correlated the findings with the presence of H. pylori and EBV infections and also with clinicopathological features of gastric carcinomas. COX2 was the most frequently hypermethylated gene (63.5%) in these patients, followed by DAPK (55.7%), CDH1 (51%), CDKN2A (36%) and hMLH1 (30.3%). In this study, MSI was correlated with hMLH1 methylation, as shown before, and there was an inverse correlation between DAPK hypermethylation and MSI. Also, MSI was inversely correlated with H. pylori CagA+, providing new evidence for the association of MSI and better prognosis.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Platelet-derived growth factor A mRNA in platelets is associated with the degree of hepatic fibrosis in chronic hepatitis C

Abstract: INTRODUCTION: Transforming growth factor beta 1 (TGFB1) and platelet-derived growth factor (PDGF) are the main cytokines related to hepatic fibrogenesis. METHODS: RNA isolated from the platelets and hepatic tissue of 43 HCV carriers was used for quantitative polymerase chain reaction to determine TGFB1, PDGFA, and PDGFB RNA expression. RESULTS: The mRNA expression of PDGFA in platelets was significantly lower in the group with advanced fibrosis than in the group with early-stage fibrosis. TGFB1 was more frequently expressed in platelets than in hepatic tissue, which was different from PDGFB. CONCLUSIONS: A pathway mediated by overexpression of TGFB1 via PDGFA in megakaryocytes could be involved in the development of fibrosis

Detecção do vírus Epstein-Barr (EBV) em adenocarcinomas gástricos procedentes dos estados do Ceará e de São Paulo

INTRODUÇÃO: O vírus Epstein-Barr (EBV) está associado a cerca de 10% dos adenocarcinomas gástricos, representando mais de 50 mil casos por ano no mundo. Apesar dos estudos realizados em várias partes do mundo, alguns aspectos clinicopatológicos permanecem controversos. OBJETIVOS: O presente estudo teve como objetivo analisar as características clinicopatológicas de casos de adenocarcinomas gástricos procedentes dos estados de São Paulo e Ceará, correlacionando-os com a detecção de EBV. MATERIAIS E MÉTODOS: Foram obtidos 192 casos de adenocarcinomas gástricos de hospitais dos estados de São Paulo e do Ceará, dos quais 160 foram submetidos à técnica de RNA-hibridização in situ para detecção de EBV. RESULTADOS: Dos 160 casos, 11 (6,9%) foram EBV-positivo, exibindo intensa marcação nuclear em células tumorais. Destes, dois casos também apresentaram linfócitos infiltrados marcados. Não encontramos marcação em tecido normal ou pré-neoplásico. São Paulo e Ceará apresentaram as frequências 3/60 (5%) e 8/100 (8%), respectivamente, e maior relação do EBV com indivíduos do sexo masculino, de idade avançada, com tumores do tipo intestinal, de estadiamento elevado e grau pouco a moderadamente diferenciado. Os casos do Ceará exibiram aumento relativo de tumores EBV(+) localizados na cárdia, enquanto os casos de São Paulo demonstraram aumento naqueles localizados no corpo gástrico. CONCLUSÃO: A frequência de tumores EBV(+) do presente estudo situa-se nos valores descritos na literatura mundial. Entre os achados, um deles não encontra paralelo na literatura mundial e refere-se ao elevado percentual de tumores EBV(+) no corpo gástrico observado nos casos de São Paulo.INTRODUCTION: The Epstein-Barr virus (EBV) has been associated with approximately 10% of gastric adenocarcinomas, which represents more than 50,000 cases/year worldwide. Despite the studies undertaken in several countries, some clinical-pathological aspects remain contentious. OBJECTIVE: The objective of this study was to analyze clinical-pathological features of gastric adenocarcinomas from two Brazilian states, São Paulo and Ceará, by correlating them with EBV detection. MATERIALS and METHODS: One hundred ninety-two gastric adenocarcinoma cases were selected from hospitals in São Paulo and Ceará, of which 160 were submitted to RNA in situ hybridization for EBV detection. RESULTS: Eleven (6.9%) out of 160 cases were EBV-positive with intense nuclear staining in tumor cells. Among these, two cases also showed stained infiltrating lymphocytes. There was no staining in normal or preneoplastic tissue. São Paulo and Ceará yielded the respective results: 3/60 (5%) and 8/100 (8%). In both states, EBV was more prevalent among elder male patients with little to moderately differentiated intestinal tumors in advanced stage. Ceará cases substantiated a relative increase in EBV(+) tumors located in the cardia, whereas São Paulo cases presented an increase in the gastric corpus. CONCLUSION: The frequency of EBV(+) tumors is similarly described in the literature. Among our findings, the elevated percentage of EBV(+) tumors in the gastric corpus, which was observed in São Paulo cases, is unprecedented in the literature

Epstein-Barr virus-associated gastric carcinoma in Brazil: comparison between in situ hybridization and polymerase chain reaction detection

Epstein-Barr virus (EBV) has been associated with 10% of gastric carcinomas. The aim of this study was to determine the frequency of EBV in gastric carcinomas in Brazil assessed by in situ hybridization (ISH) and PCR, which would contribute to the characterization of the clinical and pathological aspects of EBV-associated gastric carcinomas. One hundred and ninety-two gastric carcinoma cases were collected at hospitals in two Brazilian states. Seventy-three out of 151 cases were PCR(+), while 11/160 cases were ISH(+). Nine out of eleven ISH(+) cases displayed a diffuse staining pattern and 2 out of 11 a focal pattern. Both techniques showed that the EBV(+) cases were characterized by their association with males, older patients, lower gastric region, intestinal type, advanced stage and poorly to moderately differentiated tumors. The concordance between the two techniques was 55.8% (Cohen's kappa index = 0.034). Four cases were ISH(+)/PCR(-), while 49 cases were PCR(+)/ISH(-). Only two cases showed stained lymphocytes by ISH and one of them was PCR(-). The observed discrepancy between the two techniques could not be explained just by the elevated accuracy of PCR. ISH(+)/PCR(-) carcinomas may be encountered if EBV is not present in the whole tumor tissue or if there are polymorphisms in the sequences of the viral genome amplified. On the other hand, the high frequency of PCR(+) results associated with the absence of ISH staining in lymphocytes and/or tumors cells suggests that the virus may be present in tumor cells or other cell types without expressing EBER1, the target of the ISH technique

Inactivation of COX-2, HMLH1 and CDKN2A Gene by Promoter Methylation in Gastric Cancer: Relationship with Histological Subtype, Tumor Location and Helicobacter pylori Genotype

Objective: We aimed to evaluate the inactivation of COX-2, HMLH1 and CDKN2A by promoter methylation and its relationship with the infection by different Helicobacter pylori strains in gastric cancer. Methods: DNA extracted from 76 H. pylori-positive gastric tumor samples was available for promoter methylation identification by methylation-specific PCR and H. pylori subtyping by PCR. Immunohistochemistry was used to determine COX-2, p16(INK4A) and HMLH1 expression. Results: A strong negative correlation was found between the expression of these markers and the presence of promoter methylation in their genes. Among cardia tumors, negativity of p16(INK4A) was a significant finding. on the other hand, in noncardia tumors, the histological subtypes had different gene expression patterns. In the intestinal subtype, a significant finding was HMLH1 inactivation by methylation, while in the diffuse subtype, CDKN2A inactivation by methylation was the significant finding. Tumors with methylated COX-2 and HMLH1 genes were associated with H. pylori vac A s1 (p = 0.025 and 0.047, respectively), and the nonmethylated tumors were associated with the presence of the gene flaA. Conclusions: These data suggest that the inactivation of these genes by methylation occurs by distinct pathways according to the histological subtype and tumor location and depends on the H. pylori genotype. Copyright (C) 2011 S. Karger AG, Base