Relationship between levels of DNA damage in lymphocytes and histopathological severity of chronic hepatitis C and various clinical forms of hepatitis B

Abstract

A significant proportion of cancer is attributable to DNA damage caused by chronic infection and inflammation. Because both hepatitis B and C viruses (HBV and HCV, respectively) cause chronic infection and inflammatory disease, the aim of the present study was to investigate whether there is a difference in peripheral DNA damage in patients with chronic HCV compared with patients with chronic HBV; and whether there is an association in the level of peripheral DNA damage with a natural history of HBV infection. Twenty patients with chronic hepatitis C, 20 patients with chronic hepatitis B, 11 patients with cirrhosis secondary to hepatitis B, 12 inactive hepatitis B s antigen (HBsAg) carriers and 21 healthy subjects were included in the study. The DNA damage in lymphocytes was determined using the alkaline comet assay. Although the chronic hepatitis C group had similar levels of DNA damage compared with patients with cirrhosis due to hepatitis B (P > 0.05) and non-cirrhotic patients with chronic hepatitis B (P > 0.05), they had higher levels of DNA damage compared with inactive HBsAg carriers (P = 0.021) and controls (P = 0.001). Hepatitis B cirrhotic patients and patients with chronic hepatitis B had significantly higher levels of DNA damage than inactive HBsAg carriers (P = 0.002 and P = 0.012, respectively) and controls (both P = 0.001). Linear logistic regression analysis showed that chronic hepatitis C and HBV-related cirrhosis were discriminators in determining DNA damage in lymphocytes (beta 0.424 and P = 0.013, beta 0.393 and P = 0.016, respectively). Chronic hepatitis C, based on the severity of liver disease, or cirrhosis as an advanced form of HBV infection increase DNA damage in lymphocytes independently of confounding factors such as age, gender, body mass index and smoking habits.