lncRNA SNHG3 accelerates the proliferation and invasion of non-small cell lung cancer by downregulating miR-340-5p.

Small nucleolar RNA host genes (SNHGs) as a subset of long non-coding RNAs (lncRNAs) act critical roles in tumor progression. The present study aimed to elucidate the role and mechanisms of SNHG3 in non-small cell lung cancer (NSCLC). The correlation of SNHG3/miR-340-5p/HOXA10 with the clinicopathological features and outcomes in NSCLC was analyzed by TCGA cohort. In vitro and in vivo functional experiments were conducted to assess the role of SNHG3 in NSCLC cells. Bioinformatic analysis and luciferase gene reporter were used to estimate the interaction between miR-340-5p and SNHG3/HOXA10 3'UTR. The effects of SNHG3 and (or) miR-340-5p on HOXA10 expression were detected by qRT-PCR and Western blot analysis. As a consequence, the elevated expression of SNHG3 and HOXA10 or lowered expression of miR-340-5p was related to the lymph node infiltration, distant metastases and unfavorable prognosis in NSCLC. Ectopic expression of SNHG3 boosted the proliferation and invasion of NSCLC cells in vitro and in vivo, whereas downregulation of SNHG3 reversed these effects. Moreover, SNHG3 could bind with miR-340-5p and reduce its expression levels, and miR-340-5p attenuated SNHG3-induced tumor proliferation and HOXA10 expression in NSCLC cells. Our findings unveiled that SNHG3 might be an oncogenic factor in NSCLC by downregulating miR-340-5p. Copyright 2020 Biolife Sas. www.biolifesas.org.