Long non-coding RNA OR3A4 is associated with poor prognosis of human non-small cell lung cancer and regulates cell proliferation via up-regulating SOX4.

Abstract

Recent studies have uncovered that long noncoding RNAs (lncRNAs) play a crucial role in the progression of malignant tumors. Non-small cell lung cancer (NSCLC) is a common type of fatal cancer worldwide. The aim of this study was to identify the specific function of lncRNA OR3A4 in the progression of NSCLC, and to explore the possible underlying mechanism. LncRNA OR3A4 expression in 52-paired NSCLC tissues and adjacent normal tissues was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation assay and cell apoptosis assay were used to investigate the function of OR3A4 in NSCLC. Furthermore, the underlying mechanism was explored by qRT-PCR and Western blot assay. OR3A4 expression was remarkably upregulated in NSCLC tissues when compared with adjacent normal tissues. The overall survival of NSCLC patients in high OR3A4 expression group was significantly worse than those in low OR3A4 expression group. After the silence of OR3A4, the proliferation of NSCLC cells was significantly inhibited. Besides, the apoptosis of NSCLC cells was remarkably promoted after the silence of OR3A4. Meanwhile, knockdown of OR3A4 significantly down-regulated the mRNA and protein levels of SOX4 in NSCLC cells. Furthermore, the expression of SOX4 was found upregulated in both NSCLC tissues and cells. These above results suggested that OR3A4 could promote cell proliferation and suppress cell apoptosis in NSCLC through up-regulating SOX4. Our findings demonstrated that OR3A4 might serve as a new therapeutic intervention for NSCLC patients.