The role of microRNAs in primary liver cancer.

Small RNA molecules such as microRNAs, for many years considered to be superfluous genomic material, are now known to play important regulatory roles in apoptosis, cell proliferation and differentiation, angiogenesis and thus in carcinogenesis. Primary liver carcinomas such as hepatocellular carcinomas, cholangiocarcinomas and mixed variants show a rising incidence with high mortality among affected patients but lack effective targeted therapies except the new multiple kinase inhibitor Sorafenib. This review elucidates the recent contributions of miRNA gene expression analyses to a better understanding of the complex molecular interactions in liver carcinogenesis and highlights their future promise to provide novel tools for improved diagnostics, more accurate prognostic assessment and tailored molecular therapies in liver cancer.