DNA Damage Sensor γ

Background. Phosphorylated histone H2AX (γ-H2AX) is a potential regulator of DNA repair and is a useful tool for detecting DNA damage. To evaluate the clinical usefulness of γ-H2AX in hepatocellular carcinoma (HCC), we measured the level of γ-H2AX in HCC, dysplastic nodule, and nontumorous liver diseases. Methods. The level of γ-H2AX was measured by immunohistochemistry in fifty-eight HCC, 18 chronic hepatitis, 22 liver cirrhosis, and 19 dysplastic nodules. Appropriate cases were also examined by fluorescence analysis and western blotting. Results. All cases with chronic liver disease showed increased levels of γ-H2AX expression. In 40 (69.9%) of 58 cases with HCC, the labeling index (LI) of γ-H2AX was above 50% and was inversely correlated with the histological grade. Mean γ-H2AX LI was the highest in dysplastic nodule (74.1±22.1%), which was significantly higher than HCC (P<0.005). Moreover, γ-H2AX was significantly increased in nontumorous tissues of HCC as compared with liver cirrhosis without HCC (62.5±24.7%, from 5.1 to 96.0%, P<0.005). Conclusions. γ-H2AX was increased in the preneoplastic lesions of HCC and might be a useful biomarker for predicting the risk of HCC

p27 Is a Critical Prognostic Biomarker in Non-Alcoholic Steatohepatitis-Related Hepatocellular Carcinoma

Non-alcoholic steatohepatitis (NASH) is a recently identified chronic liver disease, which progresses to liver cirrhosis and hepatocellular carcinoma (HCC). As the number of patients studied to date has been limited, clinically useful prognostic biomarkers of NASH-related HCC have not been available. In this study, we investigated the status of a cell-cycle regulator, p27, in NASH-related HCC. p27 has been regarded as a prognostic factor in various types of cancer patients. A total of 22 cases with NASH-related HCC were analyzed for p27 protein expression, and phosphorylation at threonine 157 (T157) and serine 10 (S10) by immunohistochemical analysis. The correlation of p27 with tumor characteristics, disease-free survival (DFS), and overall survival was analyzed. p27 expression was decreased in 13 HCCs (59%), and was significantly correlated with enlarged tumor size (p = 0.01) and increased cell proliferation (p &lt; 0.01). Phospho-p27 at T157 and S10 was detected in four (18%) and seven (32%) cases, respectively, and patients positive for phospho-p27 (S10) showed reduced DFS (hazard ratio 7.623, p = 0.016) by univariate analysis. Further studies with more patients are required to verify the usefulness of p27 as a biomarker for predicting tumor recurrence in NASH patients