Circ_0008351 acts as ceRNA for miR-942-5p to inhibit the progression of gastric cancer depending on the activation of PTGDR2

Circular RNAs (circRNAs) play a vital role in the malignant progression of gastric cancer (GC) as functional RNAs. However, the exact role and mechanism of circ_0008351 in GC remain unclear. QRT-PCR was used to measure circ_0008351, microRNA (miR)-942-5p and prostaglandin D2 receptor 2 (PTGDR2) expression. Cell functions were analyzed by colony formation assay, EdU assay, tube formation assay, transwell assay and flow cytometry. The interaction between miR-942-5p and circ_0008351 or PTGDR2 was verified by dual-luciferase reporter assay and RNA pull-down assay. The role of circ_0008352 in vivo was confirmed by constructing xenograft models. Circ_0008351 was lowly expressed in GC tissues and cells, and its overexpression suppressed GC cell growth, angiogenesis and metastasis. MiR-942-5p was sponged by circ_0008351, and it could abolish the growth, angiogenesis and metastasis of GC cells inhibited by circ_0008351. PTGDR2 was targeted by miR-942-5p, and its expression was promoted by circ_0008351. The inhibition effect of circ_0008351 on GC cell growth, angiogenesis and metastasis also were reversed by knockdown of PTGDR2. Animal experiments showed that overexpressed circ_0008351 also inhibited GC tumor growth. Circ_0008351 suppressed GC progression through upregulating PTGDR2 via sponging miR-942-5p, providing a new insight into the treatment of GC.