Hsa_circ_0003159 inhibits gastric cancer progression by regulating miR-223-3p/NDRG1 axis

Background: Abnormally expressed circular RNAs (circRNAs) are implicated in the development and treatment of gastric Cancer (GC). Previous study has reported that hsa_circ_0003159 is expressed in GC. However, the role and mechanism of hsa_circ_0003159 in GC progression remain unclear.

Methods: GC tissues and normal tissues were harvested from 55 patients in this study. The levels of hsa_circ_0003159, MicroRNA (miR)-223-3p and N-myc downstream regulated gene 1 (NDRG1) were measured by quantitative real-time polymerase chain reaction or western blot. Cell proliferation, migration, invasion and Apoptosis were determined by cell counting kit (CCK)-8, transwell assay, flow cytometry and western blot, respectively. The target association of miR-223-3p-hsa_circ_0003159 and miR-223-3p-NDRG1 was explored by dual-luciferase reporter assay. Xenograft model was established to assess the roles of hsa_circ_0003159 in GC in vivo.

Results: Hsa_circ_0003159 was lowly expressed in GC tissues and cells and mainly presented in the cytoplasm. Low expression of hsa_circ_0003159 was associated with lower overall survival and disease-free survival. Hsa_circ_0003159 overexpression inhibited proliferation, migration and invasion but induced Apoptosis in GC cells. MiR-223-3p was a target of hsa_circ_0003159 and abated the effect of hsa_circ_0003159 on proliferation, migration, invasion and Apoptosis in GC cells. Hsa_circ_0003159 promoted NDRG1 expression by competitively sponging miR-223-3p. Knockdown of NDRG1 reversed the suppressive effect of hsa_circ_0003159 on GC progression. Besides, hsa_circ_0003159 decreased GC cell xenograft tumor growth by regulating miR-223-3p and NDRG1.

Conclusion: Hsa_circ_0003159 suppressed proliferation, migration, invasion and xenograft tumor growth but promoted Apoptosis by decreasing miR-223-3p and increasing NDRG1 in GC, indicating a novel target for treatment of GC.