EBioMedicine | 2021
Circular RNAs as putative biomarkers for depression diagnosis and treatment
Abstract
Major depressive disorder (MDD) is a prevalent psychiatric disorder associated with significant global burden for individuals, families, and society at large [1]. MDD is frequently chronic and resistant to treatment. Despite the availability of numerous effective treatments, the majority of depressed individuals remain undertreated and treatment outcomes remain unsatisfactory, with insufficient numbers of adequately treated individuals achieving symptomatic remission, and many requiring multiple treatment trials [2]. Clinicians currently have little biologically-based guidance available to aid them in effectively matching depressed individuals with the treatment that is most likely to benefit them, nor is it currently possible to accurately predict the development of depression in those who may be at risk. These issues have led the field to expeditiously identify and evaluate potential biomarkers that may allow for meaningful prediction of disease onset and course, as well as greater precision and targeted treatment approaches for individuals with depression. Several individual biomarker candidates have emerged in recent years and have shown promising associations with characteristics of depression and prediction of treatment response, but none as yet are routinely utilized as part of clinical care. The symptomatic heterogeneity associated with depressive disorders, coupled with the vast numbers and complexity of associated biologic, neurochemical, and physiologic processes has made progress slow, albeit steady [3]. Thus, the field is still in the very preliminary stages of evaluation of putative biomarker candidates to inform the clinical care of depression, with subsequent investigations needed to establish potential clinical utility, as well as the need for integration of multiple and/or multimodal biomarkers to increase precision. Circular RNAs, or circRNAs, have increasingly gained attention as promising biomarker targets to inform disease diagnosis and