LncRNA CASC7 was found to be downregulated in NSCLC tissues and was correlated with poor prognosis in NSCLC patients. (A) CASC7 expression levels in 80 paired NSCLC and adjacent tissues by RT-qPCR; **P<0.01 vs. normal tissues. (B) Expression analysis of CASC7 in NSCLC and adjacent tissues from NSCLC patients using immunohistochemistry (magnification, ×400). (C) Kaplan-Meier analysis of overall survival in NSCLC patients with high and low CASC7 expression levels (n=31 and n=49, respectively); **P<0.01 vs. low CASC7 group. (D) RT-qPCR analysis of CASC7 expression levels in NSCLC cells (A549, H358 and H2170) and one normal human bronchial epithelial cell line (16HBE) that was used as a control. Data are presented as means ± standard deviation from three independent experiments; **P<0.01 vs. 16HBE cells. (E and F) RT-qPCR analysis of CASC7 expression levels in A549 and H358 cells following pcDNA-CASC7 or si-CASC7 transfection. Data are presented as means ± standard deviation from three independent experiments; **P<0.01 vs. pcDNA-vector or si-Scramble. NSCLC, non-small cell lung cancer; RT-qPCR, reverse transcription-quantitative PCR.