ARTICLE ABSTRACT
Recently, long noncoding RNAs (lncRNA) have been reported as tumor suppressors or oncogenes in colorectal cancer. This study aims to discover functional role of a novel lncRNA in colorectal cancer tumorigenesis. Expression profile of fibronectin type III domain containing 1 antisense RNA 1 (ELFN1-AS1) in colorectal cancer samples was displayed on TCGA database. Expression level of ELFN1-AS1 was tested in colorectal cancer tissues and cell lines via qRT-PCR. Functional role of ELFN1-AS1 was assessed by loss-of-function assays. Mechanism experiments, such as chromatin immunoprecipitation (ChIP) assay and luciferase reporter assay, were done to analyze the molecular mechanism of ELFN1-AS1 in colorectal cancer. ELFN1-AS1 knockdown inhibited colorectal cancer tumor growth through restricting cell proliferation and facilitating cell apoptosis. ELFN1-AS1 was transcriptionally activated by MYC. Moreover, ELFN1-AS1 led to transcriptional silencing of tropomyosin 1 (TPM1) via recruiting enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) and forkhead box P1 (FOXP1). Collectively, MYC-upregulated ELFN1-AS1 recruited EZH2 and FOXP1 to restrain TPM1 expression, thereby promoting colorectal cancer tumor growth.
This study revealed a novel molecular pathway in colorectal cancer progression, which may provide new method for early diagnosis and treatment of colorectal cancer.
