In conclusion, our findings show that circPTK2 (hsa_circ_0008305) inhibits TGF-β-induced EMT and metastasis by controlling TIF1γ in NSCLC, revealing that circPTK2 has an important role in regulating TGF-β-induced EMT and tumor metastasis, and suggesting a rationale for therapeutically upregulating circular RNAs in patients with advanced NSCLC. Here, TGFB1 is linked to neoplasm.