Large noncoding RNA HOTAIR enhances aggressive biological behavior and is associated with short disease-free survival in human non-small cell lung cancer

HOTAIR is one of long non-coding RNAs and its expression correlates with the prognosis and metastasis in various cancers. We showed that HOTAIR expression has an important role in the development of non-small cell lung cancer (NSCLC). In this study, we examined the expression of HOTAIR in 77 NSCLCs, their corresponding normal lung tissues and 6 brain metastases by quantitative real-time RT-PCR. High expression of HOTAIR (tumor/normal ratio ⩾2) was detected in 17 patients (22.1%) and was frequently found in patients with advanced stage, lymph node metastasis or lymph-vascular invasion and short disease free interval. Furthermore, brain metastases show significantly higher HOTAIR expression compared to primary cancer tissues. HOTAIR-expressing A549 cells showed induced cell migration and anchorage-independent cell growth in vitro. These results indicate the expression of HOTAIR enhanced the aggressive behavior of NSCLC cells.