MicroRNAs as novel biomarkers in spinal muscle atrophy: analysis from muscular miRnome

The identification of biomarkers is a critical issue in several conditions, including spinal muscle atrophy (SMA), a neuromuscular disorder. These tools are necessary for the objective evaluation of patients' function, also in response to different therapeutics. MicroRNAs (miRs) can be stably detected in serum and are considered a promising class of disease biomarkers. In the present study, we determined by Next Generation Sequencing (NGS) the miRNome of muscle biopsies and cultured muscle cells of patients and controls, to identify miRs with a potential pathogenic role in SMA and/or related to the degenerative process of skeletal muscle. To evaluate their potential applicability as biomarkers, deregulated miRs were subsequently quantified by absolute real time PCR in a large cohort of patients and controls. Among the miRs tested so far, three are emerged as novel biomarkers for SMA and their expression correlates with the severity of condition. We report for the first time the miR expression profiling of SMA muscle samples. A specific miR signature distinguishes SMA samples from controls, and may provide novel potential targets for therapeutic strategies.