Objective: To explore the effect and mechanism of down-regulating lncRNA TTTY15 targeting miR-4500 on the proliferation, apoptosis, migration and invasion of A172 glioma cells.
Methods: The difference in TTTY15 expression between the glioma cells and tissue was determined with a qRT-PCR method. Complementary binding sites of TTTY15 and miR-4500 were predicted with Starbase software, and the targeting relationship was validated with a luciferase reporter system. A172 glioma cells were divided into Control, si-NC (transfected with control siRNA), si-TTTY15 (transfected with TTTY15 siRNA), si-TTTY15+Anti-miR-NC (co-transfected with TTTY15 siRNA and inhibitor control) and si-TTTY15+Anti-miR-4500 (co-transfected with TTTY15 siRNA and miR-4500 inhibitor) groups. Proliferation, apoptosis, migration and invasion, and the expression of Bax, Bcl-2, MMP-2 and MMP-9 proteins of the A172 glioma cells were respectively detected with CCK-8, flow cytometry, Transwell chamber and Western blotting assays.
Results: The expression of TTTY15 in glioma cells and glioma tissues have both increased. The expression levels of TTTY15 and miR-4500 in glioma tissues were inversely correlated. TTTY15 and miR-4500 are mutually targeted. Compared with those of the Control and si-NC groups, the glioma cells in the si-TTTY15 group showed increased level of miR-4500, decreased survival rate, increased apoptosis rate, enhanced cell migration and invasion, increased expression of Bax protein, and decreased expression of Bcl-2, MMP-2 and MMP-9 proteins (P<0.05). Compared with those of the si-TTTY15+Anti-miR-NC group, the A172 glioma cells in the si-TTTY15+Anti-miR-4500 group showed decreased level of miR-4500, increased cell survival rate, decreased apoptosis rate, enhanced cell migration and invasion, decreased expression of Bax protein, and increased expression of Bcl-2, MMP-2, and MMP-9 proteins (P<0.05).
Conclusion: Down-regulating TTTY15 targeting miR-4500 can inhibit the proliferation, migration, invasion and induce apoptosis of the A172 glioma cells.