Green tea consumption, inflammation and the risk of primary hepatocellular carcinoma in a Chinese population

Abstract

Objective: Green tea has been found to possess anti-inflammatory, anti-oxidative and anti-carcinogenic properties. The present study examines the association between green tea drinking and hepatocellular carcinoma (HCC) and its interactions with other risk or protective factors and single nucleotide polymorphisms (SNP) of inflammation and oxidative stress related genes.

Methods: A population-based case-control study with 204 primary HCC cases and 415 healthy controls was conducted in Taixing, China. Epidemiological data were collected using a standard questionnaire. SNPs of genes of the inflammation and metabolic pathways were genotyped at the UCLA Molecular Epidemiology Laboratory. Logistic regression was performed to estimate adjusted odds ratios and 95% confidence intervals.

Results: Longer duration and larger quantities of green tea consumption were inversely associated with primary HCC. Individuals who drank green tea longer than 30 years were at lowest risk (adjusted OR=0.44, 95% CI: 0.19-0.96) compared with non-drinkers. A strong interaction was observed between green tea drinking and alcohol consumption (adjusted OR for interaction=3.40, 95% CI: 1.26-9.16). Green tea drinking was also observed to have a potential effect modification on HBV/HCV infection, smoking and polymorphisms of inflammation related cytokines, especially for IL-10.

Conclusion: Green tea consumption may protect against development of primary HCC. Potential effect modifications of green tea on associations between primary HCC and alcohol drinking, HBV/HCV infection, and inflammation-related SNPs were suggested.

Fig. 1

Alcohol drinking, smoking and HBV&HCV infections among different green tea drinkers. (a) Alcohol drinking, green tea drinking and HCC. Study subjects were stratified into three groups based on their green tea drinking amounts: never drinking, less than 250 g/month and more than 250 g/month. In each green tea drinking categories, the adjusted ORs of alcohol drinking were presented, using subjects who never or occasionally drank alcohol as reference. (b) HBV/HCV infection, green tea drinking and HCC. Study subjects were stratified into three groups based on their green tea drinking amounts: never drinking, less than 250 g/ month and more than 250 g/month. In each green tea drinking categories, the adjusted ORs of HBV/HCV infection were presented, using subjects who have no HBV and HCV infection as reference.