The Non-Coding RNA Repressor GAS5 of the Glucocorticoid Receptor: Insights to Its Role in Human Malignancies

Abstract

Background: GAS5 is expressed in growth arrested cells as a result of nutrient deprivation or growth factor withdrawal. Besides its roles in metabolism, GAS5 has been studied in a variety of human cancers. The aim of the present work was to review the literature and report all recent findings of the roles of GAS5 in a variety of tumors. Methods: An electronic literature search was conducted by the authors using the keywords “GAS5” and “cancer”, and then individually searched for each type of cancer that was brought up by the first search. Original articles and systematic reviews were selected, and the titles and abstracts of the papers were screened to determine whether they met the eligibility criteria. In addition, we performed computer-based structural analysis on the human GAS5 RNA for extending our understanding on its biological and/or pathological actions. Results: We have found that the majority of studies, irrespectively of tumor types, confirm the role of GAS5 as a tumor suppressor gene. Especially, more recent findings have also highlighted GAS5 interaction with miRNAs contributing even more to its tumor inhibiting role. In particular, we could outline two miRNAs, which came up throughout our review; miR-222 and miR-21. GAS5, miR-222 and miR-21 could pose potential prognostic and diagnostic biomarkers for a variety of tumors, making them quite useful in cancer clinic. Conclusions: For certain, more studies are required in order to better understand the role of GAS5 in tumor biology, and in particular the signaling pathways in which the gene participates.