Small nucleolar RNAs and their participation in cancer

Abstract

Background: Small nucleolar RNAs (snoRNAs) are RNA species of about 60-300 nucleotides of length that are involved in the processing of both small nuclear RNAs and ribosomal RNAs. The function of snoRNAs is dependent of conserved sequences called "boxes", which distinguish them, by their secondary structure and proteins with which they are associated. Based on this, snoRNAs are classified into three subtypes: C/D box and H/ACA box, and scaRNAs. The latter are located in the Cajal Bodies (CBs) and possess characteristic motifs. Although snoRNAs are highly conserved in different species, their genomic distribution and the form in which they are transcribed are highly variable, which makes more complex the snoRNAs study. Importantly, the expression and function of snoRNAs were altered in different diseases, particularly cancer. Objective: To describe the functions of snoRNAs and their involvement in cancer. Results: snoRNAs have expression changes in both tumor and in the blood serum of patients with cancer. This has allowed to propose specific snoRNAs as biomarkers with a potential use in the medical practice. Conclusions: snoRNAs have a great potential to be used in the medical practice as molecular tools for the diagnosis and prognosis of many types of cancer; however, it is necessary gain more knowledge about snoRNAs.