The clinical significance of serum miRNA-224 expression in hepatocellular carcinoma

Aim of the study
Micro-ribonucleic acids (miRNA) are small single stranded RNA molecules. They act as key regulators of several cellular processes such as proliferation, apoptosis, tumor differentiation, invasion and metastasis. Hepatocellular carcinoma (HCC) represents the most common primary liver cancer. miRNA-224 is an oncomiR that is highly upregulated in HCC tissues. The aim of the present study was to measure the relative expression of circulating miRNA-224 in the serum of patients with HCV-related liver cirrhosis and HCC and to assess its usefulness in the diagnosis of HCC.

Material and methods
Forty-eight patients were classified into two groups: 24 HCV-related HCC patients (HCC group), and 24 HCV-related liver cirrhosis patients (LC group). A third group included 24 healthy volunteers (control group). Clinical examination, imaging studies and routine laboratory investigations, including serum α-fetoprotein (AFP), were done. Quantification of serum miRNA-224 expression was performed using real time reverse transcription polymerase chain reaction (RT-PCR).

Results
The relative expression of serum miRNA-224 was significantly higher in HCC patients compared to LC patients and healthy control subjects. Its level correlated positively with the serum concentration of AFP and with Barcelona Clinic Liver Cancer (BCLC) stage of HCC. By combining miRNA-224 relative expression with AFP, their diagnostic sensitivity, specificity and accuracy increased significantly (95.0%, 92.1% and 93.2%, respectively) compared with either of the two markers alone in discriminating HCC from liver cirrhosis.

Conclusions
Serum miRNA-224 relative expression may aid in the diagnosis of HCC. Better diagnostic performance is obtained if miRNA-224 is combined with other tumor markers such as AFP.