Increased expression of OCT4 is associated with low differentiation and tumor recurrence in human hepatocellular carcinoma

Octamer binding transcription factor 4 (OCT4), a key transcription factor required to maintain self-renewal and pluripotency of human and mouse embryonic stem cells, has been recently identified to be associated with tumorigenesis and malignant transformation of many types of cancers. This study was to determine the roles of OCT4 in HCC recurrence and their impact on the clinical outcome of HCC patients. Western blot and immunohistochemical stains were used to detect the expression of OCT4 protein in 152 HCC tissues and 40 cirrhosis tissues, as well as in 6 human HCC cell lines and normal hepatocytes. OCT4 expression in HCC cell lines and tumor tissues was higher than in normal hepatocytes and cirrhosis tissues. Overexpression of OCT4 was significantly associated with low differentiation and tumor recurrence. Patients with elevated expression of OCT4 protein usually carried a poor overall survival and high recurrence rate. Multivariate analysis showed that OCT4 expression was an independent predictive factor for HCC patients survival. OCT4 might serve as a promising biomarker for the diagnosis of highly recurrent cases of HCC and could be used as a valuable indicator for predicting the prognosis of HCC.