Liver damage and senescence increases in patients developing hepatocellular carcinoma

Most patients with a hepatocellular carcinoma (HCC) have an underlying chronic liver inflammation, which causes a continuous damage leading to liver cirrhosis and eventually HCC. However, only a minority of cirrhotic patients develop HCC. To assess a possible differential impact of liver inflammation in patients developing HCC versus patients remaining tumor-free, we designed a longitudinal study and analysed liver tissue of the same patients (n = 33) at two points in time: once when no HCC was present and once several years later when an HCC was present. As a control group, we followed cirrhotic patients (n = 37) remaining tumor-free over a similar time frame.

We analysed cell damage and senescence of hepatocytes by measuring γ-H2AX positivity, p16^INK4 and p21^WAF/Cip1 expression, nuclear size, and telomere length.

γ-H2AX positivity, p16^INK4 and p21^WAF/Cip1 expression, in the first liver biopsy was similar in patients developing HCC later on and cirrhotic patients remaining tumor free. In contrast, γ-H2AX positivity, p16^INK4 and p21^WAF/Cip1 expression, was significantly higher in the second non-tumoral liver biopsy of HCC patients than in the control patients. Consequently, the individual increase in γ-H2AX positivity, p16^INK4 and p21^WAF/Cip1 expression, from the first biopsy to the second biopsy was significantly higher in patients developing HCC than in patients remaining tumor free. In addition, changes in nuclear size and telomere length revealed a more pronounced cell aging in patients developing HCC than in patients remaining tumor free.

Hepatocytes from patients developing HCC go through more pronounced cell damage and senescence in contrast to cirrhotic patients remaining tumor free.