Increased Expression of Circulating Cancer Stem Cell Markers During the Perioperative Period Predicts Early Recurrence After Curative Resection of Hepatocellular Carcinoma.

ABSTRACT

BACKGROUND: This study was designed to investigate the correlation between postoperative recurrence of hepatocellular carcinoma (HCC) and perioperative expression and dynamic changes in cancer stem cell (CSC) markers in tumors and peripheral blood. METHODS: In HCC patients who underwent curative resection (n = 64) or liver transplantation (LT) (n = 17), mRNA levels for K19, EpCAM, and CD44 in peripheral blood and HCC tissues before and after operation were examined using real-time RT-PCR. Postoperative recurrence was analyzed in patients who underwent resection. Study participants were divided into high and low ratio groups, according to the ratio of postoperative to preoperative mRNA levels for each marker. RESULTS: K19 and CD44 mRNA levels in HCC tissues were higher in patients with recurrence than those without recurrence (p < 0.05 for all). Preoperative peripheral levels of K19 and EpCAM mRNA were higher in LT patients than in resection patients, and they were also significantly higher in cirrhotic patients of Child-Pugh Class B or C than those of Child-Pugh Class A (p < 0.05 for all). A high ratio of K19 mRNA was associated with lower relapse-free rate. Additionally, a high ratio for both K19 and CD44 mRNA was an independent poor prognostic factor for relapse-free survival (hazard ratio = 3.382, p = 0.016). CONCLUSIONS: Preoperative peripheral levels of K19 and EpCAM mRNA were influenced by background liver status and HCC. Additionally, the ratio of postoperative to preoperative mRNA levels for CSC markers, especially K19 and CD44, was shown to be important to predict HCC recurrence.