Long noncoding RNAs (lncRNAs) are emerging as significant regulators of cancer development. The purposes of study were to analyze the expression levels of long noncoding RNA THAP9-AS1 (THAP9-AS1) in hepatocellular carcinoma (HCC) tissue samples and cell lines, evaluate the clinical significance of THAP9-AS1 in predicting the survival prognosis of HCC patients, and explore the biological function of THAP9-AS1 in regulating tumor progression of HCC.

The expression of THAP9-AS1 was determined by quantitative real-time PCR. The determination of HCC cell proliferation was performed using cell counting kit-8 assay. Chi-square test was used to reveal the relationship between THAP9-AS1 and clinicopathological data of HCC patients. Kaplan-Meier method, log-rank test were used to perform analyze the relationship between THAP9-AS1 and prognostic survival in HCC patients. Cox regression was used to evaluate the abilities of THAP9-AS1 to predict survival outcomes in HCC patients.

The expression of THAP9-AS1 were markedly upregulated in HCC tissue and cells. THAP9-AS1 expression was correlated with tumor size, tumor node metastasis (TNM) stage. High THAP9-AS1 expression was associated with poor prognostic survival in HCC patients. THAP9-AS1 was an independent prognostic factor for HCC patients. Overexpression of THAP9-AS1 promoted HCC cell proliferation, silencing THAP9-AS1 inhibited HCC cell proliferation.

Aberrantly highly expressed THAP9-AS1 in HCC tissues and cells was associated with tumor size, TNM stage and poor survival prognosis, and promoted HCC cell proliferation. THAP9-AS1 had the potential to serve as independent prognostic biomarker for HCC patients and provide a novel target for HCC patients’ prognostic treatment.