Previous cDNA microarray experiments revealed that the ATP-dependent DNA helicase Q4 (RECQL4) gene is overexpressed in hepatocellular carcinoma (HCC) tissues. However, the exact role of RECQL4 in HCC remains unknown. The present study aimed to investigate RECQL4 expression in HCC and to analyze the potential clinical implications of RECQL4 expression in HCC patients. The expression of RECQL4 mRNA was assessed in 205 samples of HCC tissues by reverse transcription-quantitative polymerase chain reaction. The results demonstrated that the expression of RECQL4 mRNA in HCC tissues was significantly higher compared with adjacent normal liver tissues (P<0.001). The level of RECQL4 mRNA expression was associated with high a-fetoprotein (AFP) levels (>100 ng/ml), tumor size (>6 cm), and Barcelona Clinic Liver Cancer stage (all P<0.05). Kaplan-Meier survival analysis indicated that HCC patients with higher levels of RECQL4 expression exhibited significantly shorter disease-free survival (DFS) and overall survival (OS) times compared with those with low levels of expression. Multivariate survival analysis revealed that high RECQL4 expression was a significant independent predictor for DFS [HR, 1.635; 95% confidence interval (CI), 1.062-2.515; P=0.025] and OS (HR, 1.618; 95% CI, 1.050-2.493; P=0.029) of HCC patients. These data indicated that RECQL4 might be a novel diagnostic and prognostic biomarker for HCC patients.
Keywords: ATP-dependent DNA helicase Q4; biomarker; diagnosis; hepatocellular carcinoma; prognosis.