PTBP1 restoration attenuates the effects of HOTTIP knockdown on proliferation, survival, migration, and invasion in OS cells. Saos-2 and U2OS cells co-transfected with siHOTTIP and pcDNA3.1-PTBP1 were subjected for (a) CCK-8 assay, (b) flow cytometry analysis, (c) colony formation assay, (d) transwell analysis and (e) wound-healing assay. All data were represented by 3 independent experiments. *P < 0.05; **P < 0.01; ***P < 0.001