Long non-coding RNA PCAT7 regulates ELF2 signaling through inhibition of miR-134-5p in nasopharyngeal carcinoma

While some long noncoding RNAs (lncRNAs) might promote nasopharyngeal carcinoma (NPC) initiation and progression, the involved molecular mechanisms remain largely unclear. Here, we discovered the novel LncRNA, prostate cancer associated transcript 7 (PCAT7), which was overexpressed and associated with worse prognosis in NPC. Decreased PCAT7 expression was found to significantly suppress tumor cell proliferation in vitro, and inhibited tumor growth and reduced the expression of proliferation antigen Ki-67 in vivo. Rescue assay was performed to further confirm that PCAT7 contributed to the progression of NPC through regulating miR-134-5p/ELF2 signal pathway. These results indicated that PCAT7 might contribute to the tumor progression in NPC by functioning as a ceRNA to sponge miR-134-5p. - Highlights: • PCAT7 is up-regulated in human primary NPC tissues. • Expression of ELF2 is up-regulated in primary human NPC and negatively expressed related to miR-134-5p. • MiR-134-5p inhibits the tumorigenic potential of NPC cells by down-regulating oncogenic ELF2 gene. • PCAT7's oncogenic functions are partially through reverse regulation of miRNA-134-5p, and then activation of ELF2.