Adriana Camargo Ferrasi

Gastric adenocarcinoma and Helicobacter pylori: correlation with p53 mutation and p27 immunoexpression.

INTRODUCTION Helicobacter pylori infection is an established risk factor for gastric cancer development, but the exact underlying mechanism still remains obscure. The inactivation of tumor suppressor genes such as p53 and p27(KIP1) is a hypothesized mechanism, although there is no consensus regarding the influence of H. pylori cagA(+) in the development of these genetic alterations. GOALS To verify the relationship among H. pylori infection, p53 mutations and p27(Kip1) Protein (p27) expression in gastric adenocarcinomas (GA) seventy-four tissues were assayed by PCR for H. pylori and cagA presence. Mutational analysis of p53 gene was performed by single-strand conformation polymorphism (SSCP). Seventy tissues were analyzed by an immunohistochemical method for p27 expression. RESULTS From the samples examined, 95% (70/74) were H. pylori positive, 63% cagA(+). Altered p53 electrophoretic mobility was found in 72% of cases and significantly more frequent in the presence of cagA. Considerable reduction in p27 expression (19%) was found with a tendency for association between cagA(+) and p27(-), although the results were not statistically significant. Concomitant alterations of both suppressor genes were detected in 60% of cases. In the cases cagA(+), 66.7% of them had these concomitant alterations. CONCLUSIONS The data suggest that H. pylori cagA(+) contributes to p53 alteration and indicate that concomitant gene inactivation, with reduced p27 expression, may be a mechanism in which H. pylori can promote the development and progression of gastric cancer.

CDKN2A promoter methylation is related to the tumor location and histological subtype and associated with Helicobacter pylori flaA(+) strains in gastric adenocarcinomas

Alves MKS, Lima VP, Ferrasi AC, Rodrigues MA, de Moura Campos Pardini MI, Rabenhorst SHB. CDKN2A promoter methylation is related to the tumor location and histological subtype and associated with Helicobacter pylori flaA(+) strains in gastric adenocarcinomas. APMIS 2010; 118: 297–307.

Human Platelet Antigen Genotype Is Associated With Progression of Fibrosis in Chronic Hepatitis C

Although progression of fibrosis in the chronic hepatitis C depends on environmental, viral, and host factors, genetic polymorphisms have been associated recently with this progression, including the expression of integrins, adhesion proteins. Some integrins expressed on the platelet membrane show polymorphic antigenic determinants called human platelet antigens (HPA), where the major ones are HPA‐1, ‐3, ‐5. The association between HCV infection and HPA‐5b has been demonstrated. Similarly, the HPA profile could determine if HPA is related to progression of fibrosis. The goal of this study was to evaluate the association between the frequencies of HPA‐1, ‐3, and ‐5 and degree of fibrosis in HCV‐infected patients. Genomic DNA from 143 HCV‐infected patients was used as the source for HPA genotyping by PCR‐SSP or PCR‐RFLP. Progression of fibrosis was evaluated using the METAVIR scoring system, and the patients were grouped according to degree of fibrosis into G1 (n = 81, with F1, portal fibrosis without septa or F2, few septa) and G2 (n = 62, with F3, numerous septa, or F4, cirrhosis). Statistical analysis was performed using the proportional odds model. The genotypic frequency of HPA‐1a/1b was significantly higher in the patients in G2. To evaluate the influence of the time of infection to the development of fibrosis and its effect on the genetic factor HPA‐1, 96 patients from 143 studied were evaluated considering the time of HCV infection, and these results suggest that the HPA‐1a/1b genotype promotes the development of fibrosis in HCV infection with time. J. Med. Virol. 84:56–60, 2011.

Relationship between EBV infection and expression of cellular proteins c-Myc, Bcl-2, and Bax in gastric carcinomas.

Background Epstein-Barr virus (EBV) has been related to tumorigenesis in about 10% of all gastric carcinomas. Several studies have demonstrated strong evidence of its involvement in this process, but most of the mechanisms used by the virus to control this process are still unknown. Previous studies in vitro have indicated a relationship between the virus and some cellular genes involved in processes such as proliferation and apoptosis. Objective The aim of the present study was to investigate a possible EBV-induced tumorigenic pathway involving the cellular proteins Bcl-2, Bax, and c-Myc. Study Design One hundred patients of gastric carcinoma, obtained from 2 hospitals in Fortaleza, Brazil were assessed for the presence of EBV by in situ hybridization, for the expression of Bcl-2, Bax, and c-Myc (nuclear and cytoplasmic staining) proteins by immunohistochemistry techniques, and for the apoptotic index. Results EBV was detected in 8 (8%) patients showing strong staining situated in the nuclei of the tumor cells, 6 of them displaying a diffuse pattern, and 2 demonstrating a focal pattern of staining. The correlation with the immunohistochemistry results demonstrated that none of the EBV-positive cases exhibited Bcl-2 staining. On the other hand, Bax and c-Myc (nuclear) proteins demonstrated a significant positivity index and staining scores (labeling index and H-score) in the EBV-positive group; however, the values were lower than those obtained in the EBV-negative group, notably for c-Myc nuclear protein. In contrast, the cytoplasmic staining of c-Myc protein revealed slightly higher staining values in the EBV-positive group. The balance between Bcl-2 and Bax proteins demonstrated that the majority of the evaluated cases exhibited apoptosis orientation; however, in 62.5% of the EBV-positive cases neither protein was observed. The average apoptotic index was 4.58%, demonstrating a slightly lower average in the EBV-positive group. Conclusions EBV is not related to the overexpression of Bcl-2 and c-Myc (nuclear) in gastric carcinomas; however, the results point to a possible EBV involvement with the transport mechanisms of the nuclear membrane, resulting in cytoplasmic c-Myc accumulation. The suppression of Bax expression could represent an alternative viral mechanism for inhibition of apoptosis.

The absence of the human platelet antigen polymorphism effect on fibrosis progression in human immunodeficiency virus-1/hepatitis C virus coinfected patients

INTRODUCTION Hepatic fibrosis progression in patients with chronic hepatitis C virus infections has been associated with viral and host factors, including genetic polymorphisms. Human platelet antigen polymorphisms are associated with the rapid development of fibrosis in HCV-monoinfected patients. This study aimed to determine whether such an association exists in human immunodeficiency virus-1/hepatitis C virus-coinfected patients. METHODS Genomic deoxyribonucleic acid from 36 human immunodeficiency virus-1/hepatitis C virus-coinfected patients was genotyped to determine the presence of human platelet antigens-1, -3, or -5 polymorphisms. Fibrosis progression was evaluated using the Metavir scoring system, and the patients were assigned to two groups, namely, G1 that comprised patients with F1, portal fibrosis without septa, or F2, few septa (n = 23) and G2 that comprised patients with F3, numerous septa, or F4, cirrhosis (n = 13). Fishers exact test was utilized to determine possible associations between the human platelet antigen polymorphisms and fibrosis progression. RESULTS There were no deviations from the Hardy-Weinberg equilibrium in the human platelet antigen systems evaluated. Statistically significant differences were not observed between G1 and G2 with respect to the distributions of the allelic and genotypic frequencies of the human platelet antigen systems. CONCLUSION The greater stimulation of hepatic stellate cells by the human immunodeficiency virus and, consequently, the increased expression of transforming growth factor beta can offset the effect of human platelet antigen polymorphism on the progression of fibrosis in patients coinfected with the human immunodeficiency virus-1 and the hepatitis C virus.

Human Platelet Polymorphism can be a genetic marker associated with HIV/HCV coinfection

To evaluate the associations of HPA polymorphisms ‐1, ‐3, and ‐5 with HIV/HCV coinfection were included in this study 60 HIV/HCV‐coinfected patients from the Sao Paulo State health service centers. Data reported by Verdichio‐Moraes et al. (2009: J. Med Virol 81:757–759) were used as the non‐infected and HCV monoinfected groups. Human Platelet Polymorphism genotyping was performed in 60 Patients co‐infected with HIV/HCV by PCR‐SSP or PCR‐RFLP. HIV subtyping and HCV genotyping was performed by RT‐PCR followed sequencing. The data analyses were performed using the χ2 test or Fishers Exact Test and the logistic regression model. Patients coinfected with HIV/HCV presented HCV either genotype 1 (78.3%) or non‐1 (21.7%) and HIV either subtype B (85.0%) or non‐B (15%). The Human Platelet Polymorphism‐1a/1b genotype was more frequent (P < 0.05) in HIV/HCV coinfection than in HCV monoinfection and the allelic frequency of Human Platelet Polymorphism‐5b in the Patients coinfected with HIV/HCV was higher (P < 0.05) than in HCV monoinfected cases and non‐infected individuals. These data suggest that the presence of specific HPA allele on platelets could favor the existence of coinfection. On the other hand, Human Platelet Polymorphism‐5a/5b was more frequent (P < 0.05) in HIV/HCV coinfected and HCV monoinfected groups than in the non‐infected individuals, suggesting that this platelet genotype is related to HCV infection, regardless of HIV presence. Results suggest that the Human Platelet Polymorphism profile in HIV/HCV coinfected individuals differs from the one of both HCV monoinfected and non‐infected population. So, the Human Platelet Polymorphism can be a genetic marker associated with HIV/HCV coinfection. J. Med. Virol. 87:1677–1681, 2015.

Detecção do vírus Epstein-Barr (EBV) em adenocarcinomas gástricos procedentes dos estados do Ceará e 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, Sao Paulo and Ceara, by correlating them with EBV detection. MATERIALS AND METHODS: One hundred ninety-two gastric adenocarcinoma cases were selected from hospitals in Sao Paulo and Ceara, 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. Sao Paulo and Ceara 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. Ceara cases substantiated a relative increase in EBV(+) tumors located in the cardia, whereas Sao 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 Sao Paulo cases, is unprecedented in the literature.

Human platelets antigens influence the viral load of platelets after the interaction of the platelets with HCV and HIV in vitro

INTRODUCTION In this study, we evaluated hepatitis C virus (HCV) and human immunodeficiency virus (HIV) - platelet interactions in vitro as well as human platelets antigen (HPA) polymorphisms. METHODS Platelets were obtained from 100 healthy HPA-genotyped volunteer donors and incubated with HIV or HCV. The viral load after in vitro exposure was detected. RESULTS The viral load in the platelets after exposure to the virus was higher in the HIV exposure than in the HCV exposure. CONCLUSIONS HIV-platelet ligation could be more efficient than HCV-platelet interaction. Further, the HPA-1b allele seems to influence the interaction of platelets with HCV.

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

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.

Methylation analysis of BRCA1 in gliomas

Univ Estadual Paulista, UNESP, Fac Med Vet Aracatuba, Dept Clin Surg & Anim Reprod, Sao Paulo, Brazil