circ-LDLRAD3 regulates cell proliferation, migration and invasion of pancreatic cancer by miR-876-3p/STAT3

Background:  Pancreatic cancer (PC) is one of the most lethal types of cancer in the world. The complex network of non-coding RNAs has been demonstrate to involved in the PC progression, however, the potential mechanism was still unclear. Methods:  The clinical tumor tissues and the adjacent-tumor tissues of PC were obtained from the surgery. Real-time PCR and western blot were performed to detect gene expression in appropriate manner. The interaction between circ-LDLRAD3 and miR-876-3p was determined using luciferase reporter assay and RNA pull-down. The interaction between miR-876-3p and STAT3 was determined using luciferase reporter assay. Results:  Overexpressed circ-LDLRAD3 and STAT3, while down-regulated miR-876-3p was observed in both PC tissues and cell lines. Knockdown of circ-LDLRAD3 suppressed PC cell proliferation, migration and invasion. circ-LDLRAD3 directly regulated the expression of miR-876-3p. STAT3 is the target molecular of mR-876-3p. circ-LDLRAD3 regulated the expression of STAT3 by miR-876-3p. circ-LDLRAD3 regulated cell proliferation, migration and invasion by miR-876-3p. Conclusion:  Down-regulated circ-LDLRAD3 suppressed cell proliferation, invasion and migration by directly regulating miR-876-3p/STAT3. Key words: pancreatic cancer; circ-LDLRAD3; miR-876-3p; STAT3; cell proliferation; migration and invasion