SNPing cancer in the bud: MicroRNA and microRNA-target site polymorphisms as diagnostic and prognostic biomarkers in cancer

MicroRNAs are master regulators of gene expression and control many biological pathways such as cell growth, differentiation and apoptosis. Deregulation of microRNA expression and activity results in a myriad of diseases including cancer. Recently, several reports have indicated that single nucleotide polymorphisms (SNPs) in microRNAs and microRNA-target sites impact microRNA biology and associate with cancer risk, treatment response and outcome. In this review we will describe these findings and discuss the possible future of utilizing these SNPs as diagnostic and prognostic markers in the clinic.