Association Between IL-4 and IL-6 Expression Variants and Gastric Cancer Among Portuguese Population.

INTRODUCTION: Multiple studies have reported strong associations between Helicobacter pylori (Hp) inflammation and gastric cancer (GC) development. Altered expressions of pro/anti-inflammatory cytokines have a crucial role in Hp and GC proliferation. Although there are many studies related to cytokines polymorphisms involvement in GC risk, the role of Interleukin-4 (IL-4) and Interleukin-6 (IL-6) in gastric inflammation process is not yet clarified. AIM: This study aimed to investigate the impact of common IL-4 and IL-6 polymorphisms in GC development risk among Portuguese population. METHODS: A total of 100 GC biopsies (50 with intestinal type, IGC, 50 with diffuse type, DGC) and 50 chronic gastritis cases, used as control group, were included in this case-control study. IL-4 and IL-6 common polymorphisms were genotyped by PCR-SSP, using commercially available kits. RESULTS: IL-4 low producer genotypes, IL-4-590TT (OR = 6.7; 95% CI 1.4-32.4) and IL-4-1098GG (OR = 4.4; 95% CI 1.7-16.9) were found associated with IGC and DGC, respectively. We also verified that IL-4 TTT haplotype was linked with both IGC (OR = 5.8; 95% CI 2.3-14.4) and DGC (OR = 2.3; 95% CI 1.0-5.5) groups. Concerning IL-6 results, IL-6-174CG genotype showed a higher prevalence among IGC cases (OR = 7.3; 95% CI 2.7-20.3), and IL-6-174CC (OR = 3.8; 95% CI 1.7-8.7) showed upper prevalence within DGC subjects. Finally, IL-6-174/nt565CG haplotype showed a significant association with both IGC (OR = 7.3; 95% CI 2.7-20.3) and DGC (OR = 7.9; 95% CI 4.2-14.9). CONCLUSION: IL-6 and IL-4 expression variants seem to have an important role in GC risk mechanisms. This study provides preliminary evidence that IL-4 and IL-6 polymorphisms, although not directly linked to the disease, may be useful tools in the study of this multifactorial disease.

INTRODUÇÃO: Múltiplos estudos têm referenciado fortes associações entre infeção/inflamação por Helicobacter pylori (Hp) e o desenvolvimento do cancro gástrico (CG). A alteração na expressão das citocinas pro/anti-inflamatórias desempenha um papel crucial na proliferação da Hp e do CG. Apesar de existirem vários estudos relacionados com os polimorfismos das citocinas envolvidos na progressão do CG, o papel da Interleukin-4 (IL-4) e Interleukin-6 (IL-6) no mecanismo de inflamação gástrica ainda não está totalmente esclarecido. OBJETIVO: Este estudo teve como objetivo principal estudar o impacto dos polimorfismos comuns da IL-4 e IL-6 no risco de desenvolvimento do CG na população Portuguesa. MÉTODOS: Um total de 100 biópsias de CG (50 do tipo intestinal, CGI, 50 do tipo difuso, CGD) e 50 casos de gastrite crónica, utilizados como grupo controlo, foram incluídos neste estudo de caso-controlo. Os polimorfismos da IL-4 e da IL-6 foram genotipados por PCR-SSP, utilizando kits comerciais disponíveis. RESULTADOS: Os genótipos de baixa produção da IL-4, IL-4 -590TT (OR = 6,7; 95% CI 1,4 a 32,4) e IL-4 -1098GG (OR = 4,4; 95% CI 1,7 a 16,9) encontram-se associados com o CGI e com o CGD, respetivamente. Também verificámos que o haplótipo IL-4 TTT encontra-se relacionado com ambos os grupos de CGI (OR = 5,8; 95% CI 2,3 a 14,4) e CGD (OR = 2.3; 95% CI 1,0 a 5,5). Considerando os resultados da IL-6, o genótipo IL-6-174CG apresentou uma elevada prevalência entre os pacientes com CGI (OR = 7,3; 95% CI 2,7 a 20,3), e o IL-6 -174CC (OR = 3,8; 95% CI 1,7 a 8,7) apresentou maior prevalência no grupo de CGD. Finalmente, o haplótipo IL-6 -174/nt565CG apresentou uma associação significativa com ambos os grupos de CGI (OR = 7,3; 95% CI 2,7 a 20,3) e CGD (OR = 7,9; 95% CI 4,2 a 14,9). CONCLUSÃO: Os variantes de expressão da IL-6 e IL-4 parecem desempenhar um papel importante nos mecanismos de progressão do CG. Este estudo fornece evidências preliminares de que os polimorfismos da IL-4 e da IL-6, apesar de não estarem diretamente ligados a esta patologia, podem ser ferramentas úteis no estudo desta doença multifatorial.

Human herpesvirus 6 in donor biopsies associated with the incidence of clinical cytomegalovirus disease and hepatitis C virus recurrence.

BACKGROUND: Reactivation of cytomegalovirus (CMV) and human herpesvirus 6 (HHV-6), as well as the recurrence of hepatitis C virus (HCV), occurs in the post liver transplantation period. However, their correlations remain questionable. The objectives of this study were to analyze the presence of CMV DNA and HHV-6 DNA in pre-transplant and post-transplant liver graft biopsies and to determine any correlations with CMV disease and HCV recurrence. METHODS: Forty-one liver transplant recipients were followed up in the post-transplant period. The presence of CMV DNA and HHV-6 DNA was detected by nested PCR. RESULTS: Four patients (4/41, 9.8%) were positive for CMV DNA in pre-transplant biopsies and three of them remained positive after transplantation; 11 patients became positive in the post-transplant biopsies (p=0.06). Fifteen (15/41, 36.6%) patients were positive for HHV-6 DNA in pre-transplant biopsies and 11 of these remained positive after transplantation. Another 11 patients became positive after the surgery (p=0.05). CMV disease occurred in 17 recipients; 10 of these 17 (58.8%) patients were positive for HHV-6 DNA in pre-transplant biopsies and they continued positive after transplantation (p=0.0128). Twenty-eight patients were transplanted due to hepatitis C; 12 of these patients had recurrence of the virus, and HHV-6 was positive in nine of the 12 (75%) patients (p=0.049). CONCLUSIONS: Recipients with HHV-6 DNA in pre-transplant graft biopsies remained positive post transplantation, showing a possible risk for post-transplant allograft loss because there was an association between HHV-6 and recurrent HCV and CMV disease.

Simultaneous monitoring of CMV and human herpesvirus 6 infections and diseases in liver transplant patients: one-year follow-up.

OBJECTIVE: The aim of this study was to simultaneously monitoring cytomegalovirus and human herpesvirus 6 active infections using nested-polymerase chain reaction and, together with clinical findings, follow the clinical status of patients undergoing liver transplant. INTRODUCTION: The human ß-herpesviruses, including cytomegalovirus and human herpesvirus 6, are ubiquitous among human populations. Active infections of human herpesvirus 6 and cytomegalovirus are common after liver transplantation, possibly induced and facilitated by allograft rejection and immunosuppressive therapy. Both viruses affect the success of the transplant procedure. METHODS: Thirty patients submitted to liver transplant at the Liver Transplant Unit, at the Gastro Center, State University of Campinas, SP, Brazil, were studied prospectively from six months to one year, nested-polymerase chain reaction for cytomegalovirus and human herpesvirus 6 DNA detections. Two or more consecutive positive nested-polymerase chain reaction were considered indicative of active infection. RESULTS: Active infection by cytomegalovirus was detected in 13/30 (43.3%) patients, median time to first cytomegalovirus detection was 29 days after transplantation (range: 0-99 days). Active infection by human herpesvirus 6 was detected in 12/30 (40%) patients, median time to first human herpesvirus 6 detection was 23.5 days after transplantation (range: 0-273 days). The time-related appearance of each virus was not statistically different (p = 0.49). Rejection of the transplanted liver was observed in 16.7% (5/30) of the patients. The present analysis showed that human herpesvirus 6 and/or cytomegalovirus active infections were frequent in liver transplant recipients at our center. CONCLUSIONS: Few patients remain free of betaherpesviruses after liver transplantation. Most patients presenting active infection with more than one virus were infected sequentially and not concurrently. Nested-polymerase chain reaction can be considered of limited value for clinically monitoring cytomegalovirus and human herpesvirus 6.

[Gastric carcinoma and chronic gastritis: epigenetic regulation of CDH1 (E-Cadherin), CDKN2A (p16INK4A), PTGS2 (COX-2) and EGFR genes through methylation]. / Carcinoma gástrico e gastrite crónica: regulação epigenética por metilação dos genes CDH1 (Caderina-E), CDKN2A (p16INK4A), PTGS2 (COX2) e EGFR.

The genetic and epigenetic alterations are being studied as one of the causes of gastric cancer (GC) progression and development. DNA methylation is an epigenetic alteration which leads to suppressor gene silencing and proto-oncogene activation, playing an important role in carcinogenesis. The histological types of gastric carcinoma have different genetic paths and the knowledge of the molecular bases of tumoral progression leads to diagnostic accuracy and attempted therapy. CDH1 (E-cadherin) and CDKN2A (p16(INK4A)) genes are thought to be tumoral suppressor genes and PTGS2 (COX-2) and genes are involved in tumour regulation and growth. In one hand, gene silencing as an epigenetic phenomenon, and in the other hand, gene expression enhancement due to possible demethylation, simultaneously, can facilitate carcinogénesis and tumoral progression. Our aim was to relate CDH1, p16(INK4A), COX-2 and EGFR genes DNA methylation with the several histological types of gastric carcinoma and chronic gastritis. We studied 55 formalin fixed paraffin embedded gastric biopsies: 35 were GC specimens (12 diffuse type, 15 intestinal type and 8 indeterminate type, according to Laurén's classification) and 20 samples had chronic gastritis (CG). The DNA was treated with sodium bisulfite after extraction and then performed Methylation Specific PCR (MSP). Statistical analysis was based on chi-square test and Exact Fisher's test. CpG island methylation was detected in 94% of the GC samples for CDH1, 91% for COX-2, 80% for p16(INK4A) and no methylation was detected in EGFR gene (0%). In CG, CpG island methylation was found in 100% for CDH1 and COX-2 genes, 90% for p16(INK4A) and 20% for EGFR. These results reveal significant differences in EGFR gene methylation distinguishing GC from CG (p < 0, 01), suggesting that gene demethylation leads to malignant transformation and favours the use of tyrosine-kinase inhibitors in its treatment. Genes COX2 e p16INK4A lower methylation in intestinal and diffuse types of GC, favours their different role in respective histogenesis.

Simultaneous monitoring of CMV and human herpesvirus 6 infections and diseases in liver transplant patients: one-year follow-up

OBJECTIVE: The aim of this study was to simultaneously monitoring cytomegalovirus and human herpesvirus 6 active infections using nested-polymerase chain reaction and, together with clinical findings, follow the clinical status of patients undergoing liver transplant. INTRODUCTION: The human β-herpesviruses, including cytomegalovirus and human herpesvirus 6, are ubiquitous among human populations. Active infections of human herpesvirus 6 and cytomegalovirus are common after liver transplantation, possibly induced and facilitated by allograft rejection and immunosuppressive therapy. Both viruses affect the success of the transplant procedure. METHODS: Thirty patients submitted to liver transplant at the Liver Transplant Unit, at the Gastro Center, State University of Campinas, SP, Brazil, were studied prospectively from six months to one year, nested-polymerase chain reaction for cytomegalovirus and human herpesvirus 6 DNA detections. Two or more consecutive positive nested-polymerase chain reaction were considered indicative of active infection. RESULTS: Active infection by cytomegalovirus was detected in 13/30 (43.3 percent) patients, median time to first cytomegalovirus detection was 29 days after transplantation (range: 0-99 days). Active infection by human herpesvirus 6 was detected in 12/30 (40 percent) patients, median time to first human herpesvirus 6 detection was 23.5 days after transplantation (range: 0-273 days). The time-related appearance of each virus was not statistically different (p = 0.49). Rejection of the transplanted liver was observed in 16.7 percent (5/30) of the patients. The present analysis showed that human herpesvirus 6 and/or cytomegalovirus active infections were frequent in liver transplant recipients at our center. CONCLUSIONS: Few patients remain free of betaherpesviruses after liver transplantation. Most patients presenting active infection with more than one virus were infected sequentially and not concurrently. Nested-polymerase chain reaction can be considered of limited value for clinically monitoring cytomegalovirus and human herpesvirus 6.