For instance, Xu et al. showed that circ_0000654 facilitates ESCC cell proliferation, migration, invasion, and apoptosis in vitro by sponging miR-149-5p 10, and Huang et al. reported that the upregulation of circular RNA ciRS-7 expression enhances the migration and invasion of ESCC cells by affecting miR-7/KLF4 and NF-κB signaling 11. The gene discussed is KLF4; the disease is esophageal squamous cell carcinoma.