Background: The correlation between long non-coding RNAs (lncRNAs) and gastric cancer (GC) has been indicated. As a newly found lncRNA, small nucleolar RNA host gene 22 (SNHG22) functions as an oncogene in ovarian carcinoma and breast cancer. However, its action has not been explored in GC. Herein, the purpose of the current research was to examine the influence of SNHG22 on GC development.
Methods: RT-qPCR was used to identify SNHG22 and microRNA-361-3p (miR-361-3p) in GC tissues and cells. Functional assays were implemented to measure changes on biological activities of GC cells under different transfections. Besides, after human umbilical vein endothelial cells (HUVECs) were co-cultured with supernatant of transfected GC cells, angiogenesis was assessed by tube formation assay in vitro. HMGA1 and β-catenin expression were determined. Finally, mechanistic assays, including RNA pull-down assay and dual-luciferase reporter assay, were employed to assess relationships among SNHG22, miR-361-3p, and HMGA1.
Results: SNHG22 and HMGA1 were highly expressed but miR-361-3p was poorly expressed in GC tissues. Mechanistically, SNHG22 bound to miR-361-3p, and miR-361-3p targeted HMGA1 to disrupt the Wnt/β-catenin pathway. Following SNHG22 or HMGA1 silencing or miR-361-3p upregulation, we observed a decline of proliferation, migration, and invasion of GC cells and HUVEC angiogenesis but acceleration of GC cell apoptosis and cell cycle arrest.
Conclusion: Collectively, SNHG22 silencing possessed tumor-suppressing potentials in GC development via Wnt/β-catenin pathway by binding to miR-361-3p and downregulating HMGA1, highlighting a new promising road for GC treatment development.
Keywords: gastric cancer, long noncoding RNA SNHG22, microRNA-361-3p, HMGA1, Wnt/β-catenin pathway