BTRC and nasopharyngeal carcinoma: RNA pull-down (Fig. 3D) and RNA immunoprecipitation (Fig. 3E) results verified that the mutant circPVT1 (△circPVT1) could not bind to β-TrCP and had no effect on the migration and invasion abilities of NPC cells compared with the wild type circPVT1 (Fig. S3D-E).