The long non-coding RNA SNHG3 functions as a competing endogenous RNA to promote malignant development of colorectal cancer

Accumulating evidence has revealed that aberrantly expressed long non-coding transcripts are involved in the development and progression of colorectal cancer (CRC). Small nucleolar RNA host gene 3 (SNHG3) is a newly identified lncRNA, and little is known about its clinical significance and biological functions in the development of CRC. In the present study, we found that the expression of SNHG3 was significantly upregulated in CRC, and upregulation of SNHG3 predicted poor prognosis for patients with CRC as determined through analysis of the data obtained from TCGA database. Gain-of function and loss-of function assays revealed that SNHG3 markedly promoted cellular proliferation of CRC cells. Gene Set Enrichment Analysis (GSEA) suggested that high expression of SNHG3 was positively associated with c-Myc and its targets genes. Furthermore, ectopic overexpression of SNHG3 increased the expression of c-Myc and its target genes, whereas inhibition of SNHG3 had opposite effect on the expression of c-Myc and its targets. Mechanistic investigations demonstrated that SNHG3 functioned as a competing endogenous RNA (ceRNA) to ‘sponge’ miR-182-5p, thus leading to the release of c-Myc from miR-182-5p and modulating the expression of c-Myc. In conclusion, SNHG3 promoted CRC progression via sponging miR-182-5p and upregulating c-Myc and its target genes.