Long non-coding RNA SNHG1 stimulates ovarian cancer progression by modulating expression of miR-454 and ZEB1

Ovarian cancer (OC) is highly prevalent and is associated with high mortality rates due to metastasis and relapse. In this study, we assessed the role of long non-coding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in OC to gain further insight into mechanisms that contribute to its aggressiveness. We analyzed the correlation between SNHG1, miR-454 and zinc finger E-box-binding homeobox 1 (ZEB1) using a dual-luciferase reporter assay. Alterations in cell metastasis and invasiveness were observed using wound-healing and Transwell invasion assays, respectively. Tumor xenografts allowed us to monitor liver metastasis of mice injected with A2780 cells. We found that SNHG1 is overexpressed in OC. Downregulation of SNHG1 promoted miR-454 expression and reduced ZEB1 levels. In addition, knockdown of SNHG1, also reduced the aggressiveness of A2780 and SK-OV3 cells. Furthermore, SNHG1 downregulation by siRNA hindered cell migration and invasion; however, this effect was reversed by co-transfection of miR-454 into A2780 and SK-OV3 cells. Moreover, SNHG1 increased ZEB1 expression by downregulating miR-454 and activated Akt signaling, thereby promoting epithelial-mesenchymal transition and enhancing the invasiveness of OC cells. Tumor xenograft analyses confirmed that SNHG1 affects OC proliferation and metastasis in vivo. In summary, our data demonstrate that SNHG1 plays crucial roles in tumor progression and may be a useful maker for OC prognosis.