The oncogenic role, regulatory mechanism, and clinical significance of lncRNA HIF1A-AS2 in multiple human cancers

Long non-coding RNAs (lncRNAs) are RNA molecules transcribed over 200 nucleotides in length. Although they do not encode proteins, many studies have shown that they have a dramatic involvement in human cancer by various mechanisms. Hypoxia inducible factor 1α-antisense RNA 2 (HIF1A-AS2) is a lncRNA recently described to map on human chromosome 14q23.2, whose aberrant expression has been observed in many tumor types and whose up-regulation results in poor patient clinical prognosis. Experimental studies demonstrate that HIF1A-AS2 is involved in a wide range of biological processes, including cell proliferation, invasion, migration, apoptosis, drug resistance and epithelial-mesenchymal transition (EMT). Moreover, this lncRNA promotes cancer malignancy by acting as competing endogenous RNA (ceRNA) or by directly binding to certain proteins. This article comprehensively summarizes the function, molecular mechanisms, and clinical significance of HIF1A-AS2 in malignant tumors, pointing out that HIF1A-AS2 has potential functions as diagnostic markers as well as therapeutic targets.