ObjectiveTo study the expression levels of YB-1 protein in hepatocellular carcinoma (HCC) tissues,tissues adjacent to tumour and normal liver tissues,and to explore the clinical significance.MethodsTo study the expression levels of YB-1 protein,immunochemistry was carried out on 58 HCC tissues and their corresponding adjacent tissues to tumour and on 20 normal liver tissues.The YB-1 protein with nuclear translocation was detected by Western blot in HCC tissues,tissues adjacent to tumour,normal liver tissues,HCC cell lines including QGY-7701 and SMMC-7721,and a normal hepatic cell line LO2.ResultsPositive signals of YB-1 protein were detected at a high level in HCC tissues (72.4％,42/58) when compared to tissues adjacent to tumour (41.4％,24/58) and to normal liver tissues (35 ％,7/20) (P＞0.05).The nuclear expression of YB-1 (31％,18/58) was significantly correlated with the pathologicalgrade,tumour size and portal venous invasion (P＜0.05).Using Western blot,the YB-1 protein with nuclear translocation was expressed at a higher level in HCC tissues (0.474±0.107) than in tissues adjacent to tumour and in normal liver tissues (P＜0.05).Similar results were obtained in HCC cell lines and the normal hepatic cell line (P＜0.05).ConclusionThe high expression of YB-1 in HCC and its nuclear translocation may be involved in human HCC progression.YB-1 may be a potential target for HCC treatment in the future.