Long non-coding RNA highly up-regulated in liver cancer promotes exosome secretion

Highly upregulated in liver cancer ( ) is a long non-coding RNA (lncRNA) which has recently been identified as a key regulator in hepatocellular carcinoma (HCC) progression. However, its role in the secretion of exosomes from HCC cells remains unknown. To explore the mechanism by which promotes the secretion of exosomes from HCC cells. Serum and liver tissue samples were collected from 30 patients with HCC who had not received chemotherapy, radiotherapy, or immunotherapy before surgery. expression in serum exosomes and liver cancer tissues of patients was measured, and compared with the data obtained from healthy controls and tumor adjacent tissues. The effect of upregulation in HCC cell lines and the relationship between and other RNAs were studied using qPCR and dual-luciferase reporter assays. Nanoparticle tracking analysis was performed to detect the quantity of exosomes. expression in serum exosomes of patients with HCC was higher than that in serum exosomes of healthy controls, and levels were higher in liver cancer tissues than in tumor adjacent tissues. The expression of in serum exosomes and liver cancer tissues correlated with the tumor-node-metastasis (TNM) classification, and expression in tissues correlated with that in serum exosomes. Upregulation of promoted HCC cell growth and invasion and repressed apoptosis. Notably, it also facilitated the secretion of exosomes from HCC cells. Moreover, qPCR assays showed that repressed ( ) expression. We also identified as a downstream target of . Dual-luciferase reporter assays suggested that could directly bind both and . Our findings illustrate the importance of the / / axis in HCC and provide new insights into the molecular mechanism regulating the secretion of exosomes from HCC cells.