LncRNA SNHG3 Promotes Proliferation and Metastasis of Non-Small-Cell Lung Cancer Cells Through miR-515-5p/SUMO2 Axis

Lung cancer is a global disease and a major cause of cancer-related mortality worldwide. Accumulated studies have confirmed the essential role of long non-coding RNAs (lncRNAs) in the occurrence and development of cancers. Meanwhile, there have been reports concerning the role of Small Nucleolar RNA Host Gene 3 (SNHG3) in various cancers. However, there are so far few studies on the function and mechanism of SNHG3 in lung cancer. In the present study, SNHG3 was found to be highly expressed in lung cancer tissues and cells. Downregulation of SNHG3 could inhibit cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) process. In addition, SNHG3 was found to have the ability to bind to miR-515-5p. Furthermore, Small Ubiquitin Like Modifier 2 (SUMO2) was identified to be the downstream target of miR-515-5p, which was negatively correlated with miR-515-5p expression. SNHG3 could positively regulate SUMO2 expression by sponging miR-515-5p. In addition, the rescue experiment showed that simultaneous transfection of miR-515-5p or SUMO2 siRNA could reverse the effect of SNHG3 expression on cell proliferation and metastasis. Collectively, our study demonstrates that SNHG3 can act on miR-515-5p in the form of competitive endogenous RNA (ceRNA) to regulate SUMO2 positively and thus affect the proliferation and metastasis of NSCLC cells. Findings in our study support that SNHG3/miR-515-5p/SUMO2 regulatory axis may become a potential therapeutic target for lung cancer.