High expression of ERCC5 predicts a poor prognosis in hepatocellular carcinoma

Human cells exposed to environmental or endogenous carcinogens can develop DNA damage. This DNA damage may contribute to a susceptibility to cancer; therefore, it is important to repair these defects. The nucleotide excision repair pathway (NER) is a versatile DNA repair pathway that eliminates a wide variety of helix-distorting base lesions induced by environmental or endogenous carcinogenic sources. The excision repair cross-complementation group 5 (ERCC5) gene is a central component of NER. Ectopic expression of ERCC5 has been linked to different types of cancers, including hepatocellular carcinoma (HCC). However, previous reports, mainly based on mRNA level and the role of ERCC5 in cancer, remain conflicting and unclear. In this study, we examined 104 cases of HCC for immunohistochemistry to explore the role of ERCC5 protein in HCC. We found the expression of ERCC5 protein was significantly increased in tumor tissues compared to paracancerous ones (P<0.01). The percentage of positive staining of ERCC5 in tumor tissues was 28.8% (30/104), while only 4.8% (5/104) in paracancerous tissues. Patients with low ERCC5 expression levels had a better overall survival rate and remained disease-free longer (both P<0.01). In addition, univariate and multivariate analysis showed a high expression of ERCC5 protein and large tumor size predict a poor prognosis for patients with HCC (P<0.05).