MicroRNA dysregulation in Ataxia Telangiectasia

Ataxia Telangiectasia (AT) is a rare disorder characterized by neurodegeneration, combined immunodeficiency, predisposition to malignancies and high clinical variability. MicroRNAs (miRNAs) profiling may provide information on the pathophysiology of complex rare human diseases as they are involved in numerous biological functions including proliferation, differentiation, and DNA repair. To investigate the differential expression of miRNAs in AT patient samples with the aim of identifying miRNA signatures and correlate these patterns with disease pathogenesis. Twenty AT patients (mean age 17.7 + 9.6 years) were enrolled in the study. Clinical and genetic data were collected. We performed a small RNA-seq analysis in PBMCs and fibroblasts to compare miRNA expression profiles in AT patients and controls, and to identify specific expression signatures for AT. We found 42 differentially expressed (DE)-miRNAs in blood samples and 26 in fibroblasts samples. Three DE-miRNAs, miR-342-3p, miR-30a-5p, and miR-195-5p were validated in further AT samples and their dysregulation was confirmed.We identified for the first time, an AT-associated miRNA signature in blood cells and fibroblast samples obtained from a cohort of AT patients. Several pathways were predicted commonly deregulated, mainly involved in cancer. miRNAs may provide information on AT pathophysiology and tumorigenesis. Overall design: To investigate the differential expression of miRNAs in blood cellsfromAT patients and healthy control participants, with the aim to identify miRNA signatures for AT and correlate these patterns with disease pathophysiology.