Long non-coding RNA LUCAT1 promotes tumourigenesis by inhibiting ANXA2 phosphorylation in hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) play essential roles in diverse biological processes; however, current understanding of the mechanism underlying the regulation of tumour proliferation and metastasis is limited. Lung cancer-associated transcript 1 (LUCAT1) has been reported in a variety of human cancers, while its role in hepatocellular carcinoma (HCC) remains unclear. This study aimed to determine the biological role and underlying mechanism of LUCAT1 on progression and metastasis in HCC cells and clinical specimens. Our results demonstrated that LUCAT1 was up-regulated in HCC tissues and cells. Loss- and gain-of-function studies revealed that LUCAT1 promotes the proliferation and metastasis of HCC cells in vitro and in vivo. Furthermore, RNA pulldown and Western blot assays indicated that LUCAT1 inhibited the phosphorylation of Annexin A2 (ANXA2) to reduce the degradation of ANXA2-S100A10 heterotetramer (AIIt), which in turn accelerated the secretion of plasminogen into plasmin, thereby resulting in the activation of metalloprotease proteins. In conclusion, we propose that LUCAT1 serves as a novel diagnostic and therapeutic target for HCC.