Long non-coding RNA CCAT2 is associated with poor prognosis in hepatocellular carcinoma and promotes tumor metastasis by regulating Snail2-mediated epithelial–mesenchymal transition

摘要

Increasing evidence has demonstrated that aberrant expressions of long non-coding RNAs (lncRNAs) are involved in various malignancies, including hepatocellular carcinoma (HCC). This study aimed to investigate the role of lncRNA colon cancer-associated transcript 2 (CCAT2) in the progression of HCC. Quantitative real-time polymerase chain reaction analysis confirmed that CCAT2 was upregulated in HCC cell lines and cancerous tissues compared with normal liver cell line and adjacent normal tissue samples. The level of CCAT2 was positively associated with tumor–node–metastasis stages and vessel invasion. Survival analyses revealed that high CCAT2 expression predicted poor prognostic outcomes, serving as an independent prognostic factor for HCC patients. Patients with high CCAT2 expression had a 1.849-fold increased risk of death compared with those with low CCAT2 expression. Moreover, we also found that knockdown of CCAT2 expression reduced cell migration and invasion in vitro. We further demonstrated that CCAT2 played a key role in enhancing the epithelial–mesenchymal transition (EMT) through the regulation of vimentin, E-cadherin and transcription factor snail2 expression. Taken together, our findings showed that high CCAT2 expression is associated with poor survival in HCC patients. CCAT2 promotes HCC progression by regulating Snail2-induced EMT. CCAT2 may be a prognostic biomarker and therapeutic target for HCC.