Telomerase reverse transcriptase (TERT) is reportedly expressed in various types of
cancer. However, to the best of our knowledge, the significance of subcellular expression of TERT in
hepatocellular carcinoma (HCC) has not been evaluated in detail. The present study evaluated TERT expression in resected HCC
tumor tissues using immunohistochemistry. TERT expression was assessed in both the cytoplasm and the nucleus of HCC cells. The associations between TERT expression and clinical characteristics, including expression levels of
DNA-dependent protein kinase catalytic unit (
DNA-
PKcs) and 8-hydroxyganosine (8-OHdG), were investigated. Among the 135 HCCs, TERT expression was positive only in the cytoplasm in 86
tumors (63.7%), was positive only in the nucleus in 3
tumors (2.2%), was positive in both the cytoplasm and the nucleus in 5
tumors (3.7%) and was negative in 41
tumors (30.4%). Similar results were confirmed using another antibody for TERT. Cytoplasmic TERT expression was markedly associated with
hepatitis B surface antigen, poor
tumor differentiation, and expression levels of
DNA-
PKcs and 8-OHdG. However, TERT expression in the cytoplasm or in the nucleus was not significantly associated with the overall or recurrence-free survival periods. In conclusion, TERT was mainly expressed in the cytoplasm of HCC tissues. Cytoplasmic TERT expression was closely associated with hepatitis B virus-related HCC and
DNA-
PKcs expression, as well as oxidative stress.