Low frequency of Helicobacter DNA in benign and malignant liver tissues from Baltimore, United States

Abstract

Helicobacter DNA has been reported in hepatocellular carcinoma tissues in several studies from varying geographical locations, raising the possibility that helicobacter infection may contribute to the pathogenesis of hepatocellular carcinoma. Other known risk factors for hepatocellular carcinoma show significant geographical variability, but whether the same holds for helicobacter is unknown. We studied the prevalence of Helicobacter DNA in a United States cohort of HCC, where the prevalence of helicobacter infection is low in the general population. Liver tissues from 57 individuals were examined. Thirty-five individuals had paired tumor/non-tumor samples, including 21 cases of hepatocellular carcinoma, for a total of 92 samples studied. Both Helicobacter genus and Helicobacter pylori species specific PCR was performed. Helicobacter DNA was detected in 5/57 (9%) cases, all in non-neoplastic cirrhotic liver tissues from individuals with hepatitis C infection (N=4) or alcohol liver disease (N=1). Tissues from 22 hepatocellular carcinomas and 10 cholangiocarcinomas were all negative as were tissues from 8 benign primary hepatic tumors. In conclusion, Helicobacter DNA was detectable in 9% of liver tissues in this cohort, but was not found in primary benign or malignant liver tumors. These findings indicate that Helicobacter infection is unlikely to be etiologically associated with hepatocellular carcinoma in this cohort. If Helicobacter infection does contribute to the development of hepatocellular carcinoma in general, then significant regional variability must exist.

The Association betweenHelicobacter pyloriInfection and Chronic Hepatitis C: A Meta-Analysis and Trial Sequential Analysis

“…Increasing evidence suggests that H. pylori may be a risk factor for the development of cirrhosis and HCC in patients with CHC [ 8 – 10 ]; however, some researchers have suggested that H. pylori might not contribute to the mechanism of HCV-related HCC [ 11 , 12 ]. The relationship between H. pylori and CHC remains controversial, and it is unclear whether H. pylori is associated with CHC and the progression of HCV-related cirrhosis and HCC.…”

Extragastric Manifestations of Helicobacter pylori Infection: Other Helicobacters

“…Another important complication of cirrhosis is hepatocellular carcinoma (HCC), that is mostly associated with the exposure to chronic liver infections (hepatitis B and C virus), Aspergillus mycotoxin, aflatoxin‐B1, and alcohol, but in which other unrecognized risk factors may potentially be involved. While some experimental studies have suggested that H. pylori may play a role in the developing of HCC [39], a recent study showed a low frequency of H. pylori DNA in benign and malignant liver tissues, concluding that H. pylori infection is unlikely to be etiologically associated with HCC [40], while another study described the presence of H. pylori DNA and vac A gene‐specific markers in HCC and cholangiocarcinoma specimens [41].…”

“…Gastric Helicobacter species, including NHPH, are associated with gastritis [80,81], gastric ulceration, gastric adenocarcinoma, and gastric mucosa‐associated lymphoma [82]. Several EHS have been associated with disease ranging from subclinical inflammation to cancer in the intestinal tract and hepatobiliary system [40,83–87] and an increased risk of biliary lithiasis [88,89].…”

Lower Incidence of Hepatobiliary Cancer in Helicobacter pylori-Infected Persons: A Cohort Study of 53.633 Persons

“…Any association between such prevalent diseases is of obvious pathophysiological and public health interest. Recently, as well a higher and a lower prevalence of HP DNA in liver tissue with HCC and chronic liver disease is reported and the findings are of unclear significance [13][14][15][16][17][18][19][20] . A single study from Ethiopia describes a higher prevalence of HP antigen in faeces in HCC patients compared with controls 21 .…”