miRNAs (miRs), or small approximately 22-nucleotide-long single-stranded noncoding RNA molecules, interact with 3' untranslated regions of target mRNAs, leading to inhibition of protein production. miR-214 is often dysregulated in various cancers, which governs both tumorigenic and tumor suppressive functions. This review focuses on the current knowledge of miR-214 switching in diverse forms of cancer either by its upregulation or downregulation and sheds light on the mechanism of its tumorigenic and suppressive roles. This article describes known targets and signaling pathways that impact tumorigenesis and tumor suppression and summarizes all information available on circulating levels of miR-214 to address whether miR-214 may function as a potential biomarker and therapy for cancer patients in the future.
Keywords: biomarker; miR-214; miRNAs; oncogenes; tumor suppressor.