TUCR.454 inhabits metastasis in lung cancer cells.

Transcribed ultraconserved regions (TUCRs) belong to long non-coding RNAs (lncRNAs) are transcripts longer than 200 base pair RNA with no protein-coding capacity. Previous studies showed that TUCRs serve as oncogenes or tumor suppressor genes are involved in tumorigenesis and cancer progressive. However, little is known about the expression level and biological role of TUCR.454 in lung carcinoma. Our data showed TUCR.454 is significantly down-regulated in NSCLC tissue and lung cancer cell lines, and the down-regulated TUCR.454 is associated with lymph node metastasis. Transfection with TUCR.454 markedly inhibited cell migration and invasion in A549 and H460 lung cancer cell lines. K-Ras was demonstrated to be negatively regulated by TUCR.454 at the posttranscriptional level by dual-luciferase reporter assay. Down-expression of K-Ras via siRNA inhibited NSCLC cell migration and down-regulates P63 and MMP9 in protein level, resembling that of overexpression of TUCR.454. In conclusion, these findings suggested that TUCR.454 acts as a novel tumor suppressor by targeting the K-Ras gene thus inhabiting lung cancer cell migration and invasion.