Mo1781 Molecular Detection of Helicobacter pylori in Formalin-Fixed Paraffin-Embedded (FFPE) Liver Tissue From Patients With Hepatocellular Carcinoma: Comparison of Five Methods to Extract Genomic DNA

Abstract

hepatocellular carcinoma represents one of the most common human cancers in the world, the aim of this study was to investigate the presence of H. pylori DNA in the FFPE liver from Brazilian patients with HCC. For this purpose, paraffin sections of 38 liver biopsies were used and genomic DNA was extracted using phenol/chloroform method. After that, polymerase chain reaction (PCR) analysis was carried out using H. pylori specific 16S rRNA primers and PCR products of positive samples were further identified by DNA sequencing. Results showed that 14 of the 38 samples (36,8%) amplified the 16S rRNA H. pylori gene. The nucleotide sequence of the 16S rRNA amplicons demonstrated 98% similarity to H. pylori. Considering the H. pylori positive patients, in relation to viral infection, 9 of the 14 (64%) subjects were infected by hepatitis C virus (HCV), 2 (14%) were infected by hepatitis B virus (HBV); 1 (7%) presented coinfection with HCV and HBV and 2 (15%) patients had HCC without viral infection. These data confirm the identification of H. pylori in FFPE liver tissue of Brazilian patients with hepatocellular carcinoma. Additionally, patients infected with H. pylori were most frequently infected by HCV. Further studies will be performed in these samples to detect other H. pylori molecular markers such as cagA, vacA and ureA genes and its association with viral status of patients with HCC. This study was supported by grants from FAPESP ( 2009/09889-5) and FAEPEX (10111)