Abstract: Objective To investigate the expression profile of long noncoding RNA HOTAIR in nonsmall cell lung cancer（NSCLC） tissues and four different cell lines（A549， SPC-A1，SK-MES-1 and 16HBE）， and to study its biological functions in NSCLC carcinogenesis and progression，especially on cell migration and invasion. Methods Quantitative reversetranscription PCR（qRT-PCR） was performed to detect the relative expression of HOTAIR in thirty-eight NSCLC tissues and four cell lines（A549， SPC-A1， SK-MES-1 and 16HBE）. To further explore its biological function， techniques of overexpression and RNA interference（RNAi） were applied. pcDNAHOTAIR or si-HOTAIR was transfected to up or downregulate HOTAIR expression in NSCLC cells respectively， and the transfection efficiency was evaluated by qRT-PCR. MTT assay and Transwell assay were performed to evaluate the effect of ectopic HOTAIR expression on proliferation， migration and invasion potential of NSCLC cells. Results The relative expression of HOTAIR in 38 cases of NSCLC tissues was 24.48±59.55. Compared with normal bronchial epithelium cell 16HBE, there was a relatively high expression of HOTAIR in SPC-A1 and SK-MES-1 cells， and a relatively low expression in A549 cell. The HOTAIR expression was downregulated in A549 and SPC-A1 cells at 48h after transfection of HOTAIR siRNA, and upregulated in A549 cells at 48h after transfection of pcDNA3.1HOTAIR. MTT assay indicated that RNAi-mediated suppression of HOTAIR had little effect on cell proliferation， while Transwell assay indicated that inhibition of HOTAIR by siHOTAIR could repress cell migration and invasion（P＜0.05）；conversely， overexpression of HOTAIR could significantly promote cell migration and invasion（P＜0.05）.
ConclusionThe expression of HOTAIR is significantly upregulated in NSCLC, which can promote cell migration and invasion. HOTAIR may be a new biomarker of poor prognosis in NSCLC.