ABSTRACT
Lung cancer is a common cancer that is familiar to people and has the highest global incidence; among all lung cancer patients, 85% are non-small cell lung cancer (NSCLC). A number of microRNAs (miRNAs), including miR-532-5p, are implicated in the pathophysiological processes of tumorigenesis. However, the mechanism of miR-532-5p in NSCLC remains unclear. In the current study, the expression of miR-532-5p was found to be markedly downregulated in clinical NSCLC tissues and cell lines. Further study indicated that ectopic expression of miR-532-5p inhibited NSCLC cell proliferation and invasion while accelerating in vitro, but silencing miR-532-5p had an opposite result. Furthermore, functional experiments revealed that miR-532-5p effectively blocked tumor growth in a xenograft tumor mouse model. Bioinformatics and luciferase reporter analysis verified that Yin Yang 1 (YY1) transcripts are targets of miR-532-5p. Moreover, the expression of YY1 was negatively regulated by miR-532-5p in NSCLC cells. In vivo assays indicated that downregulation of YY1 inhibited tumor growth. Notably, overexpression of YY1 effectively counteracted the tumor-suppressing effects of miR-532-5p in vitro and in vivo. In summary, this study demonstrated the tumor-suppressive role of miR-532-5p in NSCLC by regulating YY1 in vitro and in vivo.
