Knockdown of ACTA2‑AS1 promotes liver cancer cell proliferation, migration and invasion.

Long noncoding RNAs (lncRNAs) are important regulators of various cellular and biological processes. The present study aimed to investigate the functions of a novel lncRNA, ACTA2‑AS1:4, a transcript variant of smooth muscle α‑actin 2‑antisense 1 (ACTA2‑AS1), in regulating liver cancer progression. Expression of lncRNAs in liver cancer tissues and cell lines were analyzed by reverse transcription quantitative polymerase chain reaction (RT‑qPCR). Knockdown of ACTA2‑AS1:4 expression in LM3 liver cancer cells was achieved by transfection with small interfering RNAs (siRNAs) that specifically targeted ACTA2‑AS1:4. The proliferation and cell cycle progression of ACTA2‑AS1:4‑silenced LM3 cells were determined using MTS assay and flow cytometry, respectively. A Transwell system assay was used to evaluate the migration and invasion capacities of LM3 cells transfected with ACTA2‑AS1:4 siRNA. The expression levels of major genes associated with important cellular processes were finally determined by RT‑qPCR and western blot analysis. ACTA2‑AS1:4 expression in liver cancer tissues and multiple cell lines was markedly downregulated by specific siRNAs. This inhibition of ACTA2‑AS1:4 expression significantly promoted the proliferation, cell cycle progression, migration and invasion of LM3 cells. A decrease in ACTA2‑AS1:4 expression also suppressed E‑cadherin expression, increased N‑cadherin expression, decreased caspase 3 expression and increased cyclin D1 and matrix metalloproteinase expression in liver cancer cells. Downregulation of ACTA2‑AS1:4 affects a number of key mechanisms involved in liver cancer progression. These data may be important for the future of liver cancer diagnosis and subsequent treatments.