lncRNA ZNF674-AS1 inhibits the migration, invasion and epithelial-mesenchymal transition of thyroid cancer cells by modulating the miR-181a/SOCS4 axis.

Thyroid cancer (TC) is a very common endocrine cancer worldwide. Further understanding and revealing the molecular mechanism underlying thyroid cancer are indispensable for the development of effective diagnosis and treatments. Long non-coding RNAs (lncRNAs), a series of non-coding RNAs with a length of >200 nts, have been regarded as crucial regulators of many cancers playing a tumor suppressive or oncogenic role, depending on circumstances. lncRNA ZNF674-AS1 was reported to be abnormally expressed in TC, but the exact mechanism remains unclear. This study aims to probe the mechanism and roles of ZNF674-AS1 in TC. The expression patterns of RNAs and proteins were determined via qRT-PCR and western blotting, respectively. Cell proliferation, migration and invasion were detected using MTT and Transwell assays. ZNF674-AS1 and SOCS4 expression were remarkably reduced while miR-181a was upregulated in TC tissues and cells. Enforced expression of ZNF674-AS1 inhibited proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and reduced tumour growth in vivo. Mechanistic assays verified that ZNF674-AS1 directly interacted with miR-181a to increase SOCS4 expression. In addition, miR-181a overexpression aggravated proliferation, metastasis and EMT by inhibiting SOCS4. Interestingly, inhibition of miR-181a diminished the promoting effects of ZNF674-AS1 silencing on the malignant behaviours of TC cells. These data illustrated that ZNF674-AS1 alleviated TC progression by modulating the miR-181a/SOCS4 axis (graphical abstract), further suggesting that ZNF674-AS1 might be used as a therapheutic target in TC treatment.