Helicobacter species sequences in liver samples from patients with and without hepatocellular carcinoma

AIM:Only a minority of patients carrying a defined viralaetiologic agent develop cirrhosis and ultimatelyhepatocellular carcinoma(HCC),the mechanism underlyingthe worsening is still undefined.Experimental infection byHelicobacter hepaticus in mice causes chronic hepatitis andHCC and recently,more Helicobacterspecies(Helicobacterspp.)have been detected in the liver of patients sufferingfrom cholestatic diseases and HCC arising from non-cirrhoticliver.We investigated whether Helicobacterspp.sequencescould be detected in the liver of patients with cirrhosis andHCC compared to subjects with metastasis to liver fromcolon cancer.METHODS:Twenty-three liver samples from patientsoperated upon for HCC superimposed on hepatitis C virus(HCV)-related cirrhosis and 6 from patients with resectedmetastases from colorectal cancer,were tested by polymerasechain reaction for presence of genomic 16S rRNA ofHelicobacter genus using specific primers.DNA sequencingand cag A gene analysis were also performed.RESULTS:Genornic sequences of Helicobacter spp.werefound in 17 of 20(85%)liver samples from patients withHCC and in 2 of 6 samples from patients with liver metastasis.In three samples of the first group the result was uncertain.Hpyloriwas revealed in 16 out of 17 positive samples andHelicobacter pullorum in the other.CONCLUSION:Helicobacter spp.,carcinogenic in mice,were found at a higher frequency in the liver of patientswith HCV-related cirrhosis and HCC than those in patientswithout primary liver disease.