Upregulated long noncoding RNAs LINC02163 and FEZF1-AS1 exert oncogenic roles in colorectal cancer

A growing number of evidence has revealed that aberrantly expressed long noncoding RNAs (lncRNAs) are involved in the development of a variety of malignancies, including colorectal cancer (CRC). However, the clinical relevance of most lncRNAs and their potential biological functions in CRC remains poorly understood. The aim of this study was to identify the key lncRNAs related to patient prognosis as well as their biological function and underlying mechanism in CRC. Therefore, five independent datasets containing CRC and normal tissue RNA sequencing, microarray data and the corresponding clinical data from The Cancer Genome Atlas and Gene Expression Omnibus were screened. Hundreds of significantly differentially expressed lncRNAs in CRC were determined, and Kaplan-Meier analyses revealed that some of these lncRNAs were related to the overall survival and progression-free survival of patients with CRC, such as RP11-108K3.2, FOXD3-AS1, H19 and AP001469.9. Among these dysregulated lncRNAs, LINC02163 and FEZF1-AS1 were significantly upregulated in CRC tissues, suggesting that they may have oncogenic roles in CRC. Furthermore, loss of function assays revealed that downregulation of LINC02163 and FEZF1-AS1 impaired CRC cell proliferation. In addition, RNA Immunoprecipitation and Chromatin Immunoprecipitation assays determined that FEZF1-AS1 regulates CRC cell growth via interacting with LSD1 and repressing KLF2 expression. Collectively, hundreds of dysregulated lncRNAs and their associated biological roles identified in this study may provide potentially useful biomarkers and therapeutic targets for CRC.