Abstract
MicroRNAs (miRNAs) are classified as small, non-coding RNAs that play crucial roles in diverse biological processes, including cellular development, differentiation, growth, and metabolism. MiRNAs regulate gene expression by recognizing complementary sequences within messenger RNA (mRNA) molecules. Recent studies have revealed that miR-145-5p functions as a tumor suppressor in several cancers, including lung, liver, and breast cancers. Notably, miR-145-5p plays a vital role in the pathophysiology underlying HIV and chronic obstructive pulmonary diseases associated with cigarette smoke. This miRNA is abundant in biofluids and shows potential as a biomarker for the diagnosis and prognosis of several infectious diseases, such as hepatitis B, tuberculosis, and influenza. Additionally, numerous studies have indicated that other non-coding RNAs, including long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), can regulate miR-145-5p. Given the significance of miR-145-5p, a comprehensive overview focusing on its roles in health and disease is essential. This review discusses the dual role of miR-145-5p as a protagonist and antagonist in important human diseases, with particular emphasis on disorders of the respiratory, digestive, nervous, reproductive, endocrine, and urinary systems.