The Emerging Role of MicroRNAs in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is common malignancy and a leading cause of cancer death worldwide. Recent epidemiological data have demonstrated that liver cancer incidence is continuously rising and will continue to do so for more than a decade, not only South Africa and Mainland China but also in North America and Europe. Molecular profiling of changes in gene expression has improved our understanding of the HCC mechanism. MicroRNAs (miRNAs) are a class of small regulatory RNAs that function to modulate protein expression. This control allows for fine-tuning of the cellular phenotype, including regulation of proliferation, cell signaling and apoptosis. Recently, investigators have demonstrated decreased or increased expression of particular miRNAs in hepatobiliary cancer cells. Many studies have highlighted the role of miRNA in physiological processes and cancer development. Several studies have reported that some miRNAs may play a role in the development and progression of HCC. Recent investigations have suggested that the presence of single nucleotide polymorphisms in miRNA genes, their processing machinery and target binding sites affect cancer risk, treatment efficacy and patient prognosis. This review will discuss the emerging critical role of miRNAs in hepatocarcinogenesis, HCC progression and clinical outcome.