LAUSR

Objectives Pancreatic cancer (PC) is one of the most deadly malignancies in the world. Recently, circular RNAs play crucial roles in PC progression. However, the functions of circ_0058058 in PC are barely known. Methods The expression of circ_0058058, microRNA-557-5p (miR-557), and programmed cell death receptor ligand 1 (PDL1) was detected by quantitative real-time polymerase chain reaction. Functional experiments were implemented to disclose the effect of circ_0058058 deficiency on PC cell proliferation, apoptosis, invasion, angiogenesis, and immune escape. The binding relationship between miR-557 and circ_0058058 or PDL1 was identified by dual-luciferase reporter assay and RNA immunoprecipitation assay. In vivo assay was used to disclose the impact of circ_0058058 silencing on tumor formation in vivo. Results Circ_0058058 was highly expressed in PC tissues and cell lines. Knockdown of circ_0058058 repressed cell proliferation, invasion, angiogenesis, and immune escape while contributed to apoptosis in PC cells. Mechanically, circ_0058058 worked as a molecular sponge of miR-557 to regulate PDL1 expression. Moreover, circ_0058058 showed a promotional effect on tumor growth in vivo. Conclusions Our findings suggested that circ_0058058 served as miR-557 sponge to upregulate PDL1, thereby triggering PC proliferation, invasion, angiogenesis, and immune escape.