LAUSR

OBJECTIVE To detect the expression of long non-coding ribonucleic acid (lncRNA) NCK1-AS1 in non-small cell lung cancer (NSCLC), analyze the association between its expression and the clinicopathological characteristics of NSCLC patients, and study the biological function of NCK1-AS1 in vitro. PATIENTS AND METHODS The relative expression of NCK1-AS1 in NSCLC tissues and cells was detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The association between the expression of NCK1-AS1 and the clinicopathological characteristics of NSCLC was statistically analyzed. The effects of interference in the expression of NCK1-AS1 on the biological behaviors of NSCLC cells were detected via in vitro experiments, including Cell Counting Kit-8 (CCK-8) assay, colony formation assay and flow cytometry. After interference in the expression of NCK1-AS1, the expression of cyclin-dependent kinase 1 (CDK1) was determined using Western blotting. RESULTS The results of qRT-PCR showed that the expression of NCK1-AS1 was up-regulated in 50 out of 64 cases of NSCLC tissues. It was found via statistical analysis that highly expressed NCK1-AS1 was positively correlated with tumor size, TNM stage and lymph node metastasis. The results of qRT-PCR revealed that the expression of NCK1-AS1 was also up-regulated in NSCLC cells. After interference in the expression of NCK1-AS1, the proliferation of NSCLC cells was inhibited, and the cell cycle was arrested at G2/M phase. The results of Western blotting manifested that the expression of CDK1 was suppressed after interference in the expression of NCK1-AS1. CONCLUSIONS The expression of NCK1-AS1 is up-regulated in NSCLC, which indicates a poor prognosis. Highly expressed NCK1-AS1 promotes the proliferation of NSCLC cells through activating CDK1.