Activation of tumor necrosis factor-alpha system in chronic hepatitis C virus infection. Dig Dis Sci. 1997;42:2487-2494. [PMID: 9440625 DOI: 10.1023/a: 1018804426724]

Oxidative damage, pro-inflammatory cytokines, TGF-α and c-myc in chronic HCV-related hepatitis and cirrhosis

AIM: To assess whether a correlation exists between oxidative DNA damage occurring in chronic HCV-related hepatitis and expression levels of pro-inflammatory cytokines, TGF-α and c-myc.

METHODS: The series included 37 patients with chronic active HCV-related hepatitis and 11 with HCV-related compensated cirrhosis. Eight-hydroxydeoxyguanosine in liver biopsies was quantified using an electrochemical detector. The mRNA expression of TNF-α, IL-1β, TGF-α and c-myc in liver specimens was detected by semi-quantitative comparative RT-PCR.

RESULTS: TNF-α levels were significantly higher in hepatitis patients than in cirrhosis patients (P = 0.05). IL-1β was higher in cirrhosis patients (P = 0.05). A significant correlation was found between TNF-α and staging (P = 0.05) and between IL-1β levels and grading (P = 0.04). c-myc showed a significantly higher expression in cirrhosis patients (P = 0.001). Eight-hydroxydeoxyguanosine levels were significantly higher in cirrhosis patients (P = 0.05) and in HCV genotype 1 (P = 0.03). Considering all patients, 8-hydroxydeoxyguanosine levels were found to be correlated with genotype (P = 0.04) and grading (P = 0.007). Also multiple logistic regression analysis demonstrated a significant correlation among the number of DNA adducts, TNF-α expression and HCV genotype (P = 0.02).

CONCLUSION: In chronic HCV-related liver damage, oxidative DNA damage correlates with HCV genotype, grading and TNF-α levels. As HCV-related liver damage progresses, TNF-α levels drop while IL-1β and c-myc levels increase, which may be relevant to liver carcinogenesis.