Microarray analysis of microRNA expression in hepatocellular carcinoma and non-tumorous tissues without viral hepatitis

Background and Aim: MicroRNAs (miRNAs) are non-coding RNA molecules of 21–24 nt that regulate the expression of target genes in a post-transcriptional manner. Evidence indicates that miRNAs play essential roles in embryogenesis, cell differentiation, and pathogenesis of human diseases including cancer. Methods: We analyzed the miRNA expression profiles in 10 pairs of hepatocellular carcinoma (HCC) and adjacent non-tumorous tissue (NT) from 10 non-viral hepatitis patients, using a mammalian miRNA microarray containing whole human mature and precursor miRNA sequences. Results: A total of 15 miRNAs exhibited higher expression in the HCC samples than that in the NT samples, and one miRNA demonstrated lower expression in the HCC samples than in the NT samples. A total of 18 miRNAs identified valid expression only in HCC samples, with six only in NT samples. The chip results were confirmed by Northern blot analysis. Conclusion: Our study may help clarify the molecular mechanisms involved in the pathogenesis of HCC, and miRNAs potentially serve as a novel diagnostic tool of HCC.