Aberrant expression of specific microRNAs in hepatocellular carcinomas has recently been reported. We examined expression patterns of 4 microRNAs (microRNA-221, microRNA-222, microRNA-21, and microRNA-155) to evaluate their potential as relevant biomarkers by quantitative real-time reverse transcriptase-polymerase chain reaction using formalin-fixed, paraffin-embedded tissues of 115 surgically resected hepatocellular carcinoma and paired nonneoplastic liver cases as well as 21 normal liver samples from cancer-free individuals. MicroRNA-221, microRNA-222, and microRNA-21 were differentially overexpressed in hepatocellular carcinoma compared with nonneoplastic and normal livers (P <.001). The mean fold changes in microRNA-221, microRNA-222, and microRNA-21(hepatocellular carcinoma to matched nonneoplastic liver) were 4.00, 4.44, and, 3.67, respectively. In addition, nonneoplastic liver tissues displayed higher levels of microRNA-221, microRNA-222, microRNA-21, and microRNA-155 than normal livers (P <.001, respectively). However, the overexpression of the 4 microRNAs showed no consistent relevance to the known prognostic clinicopathologic parameters. High expression of microRNA-221 in hepatocellular carcinomas was significantly related to shorter time to local recurrence (P <.001) and determined as an independent predictor for local recurrence (P =.001). The fold changes in microRNA-221 (hepatocellular carcinoma to matched nonneoplastic liver) less than 1 were more commonly detected in cases of distant metastases than those of disease-free and local recurrence (P =.009). The fold changes less than 1 were related to reduced metastasis-free survival (P =.006) and thus can be used as an independent predictor of distant metastasis after surgical resection (P =.027). Based on these results, we propose the possible role of microRNA-221, microRNA-222, microRNA-21, and microRNA-155 dysregulation in hepatocarcinogenesis and the potential of microRNA-221 dysregulation for predicting local recurrence and distant metastasis after curative surgery.
Bibliographical noteFunding Information:
This work was supported by the Korea Science and Engineering Foundation grant funded by the Korean government (MEST ) (no. R13-2002-044-05001-0 ) and a Student Research Grant ( 10-11 ) from the University of Ulsan College of Medicine, Seoul, Korea.
All Science Journal Classification (ASJC) codes
- Pathology and Forensic Medicine