Overexpression of ARK5 is associated with poor prognosis in hepatocellular carcinoma.

ARK5 overexpression has been reported in a variety of human cancers. However, the role of ARK5 in hepatocellular carcinoma (HCC) remains unclear. The aim of the present study is to analyze the ARK5 protein expression in HCC tissue samples and to assess its prognostic significance for HCC. ARK5 mRNA and protein expression were determined by real-time quantitative reverse transcriptase-polymerase chain reaction and Western blot in 20 pairs of fresh frozen HCC tissues and corresponding non-cancerous tissues. In addition, ARK5 expression was analyzed by immunohistochemistry in 130 clinicopathologically characterized HCC cases. The correlation of ARK5 expression with patients' survival rate was assessed by Kaplan-Meier and Cox regression. Our results showed that the expression levels of ARK5 mRNA and protein in HCC tissues were both significantly higher than those in non-cancerous tissues. Our results showed that the high expression of ARK5 in HCC was related to tumor size (p=0.005), histological differentiation (p=0.047), and tumor stage (p=0.005). Kaplan-Meier survival analysis showed that a high expression level of ARK5 resulted in a significantly poor prognosis of HCC patients. Multivariate analysis revealed that ARK5 expression level was an independent prognostic parameter for the overall survival rate of HCC patients. In conclusion, ARK5 might play a positive role in tumor development and could serve as an independent predictor of poor prognosis for HCC.