Lentiviral pu6 luc puro vector

To generate hsa_circRNA_102209 or RIN1 overexpression model, wildtype (WT; o/e‐102209 or o/e‐RIN1) as well as mutant (o/e‐NC) fragment was inserted into PLCDH‐cir vector (Ribobio). In hsa_circRNA_102209 knockdown model, shRNA sequences against hsa_circRNA_102209 (sh‐102209) or negative control (sh‐NC) were obtained from Genepharm Co. Ltd. (Shanghai, China). After annealing, shRNA were integrated into lentiviral pU6‐Luc‐Puro vector (Genepharm Co. Ltd.). The lentiviral vectors were obtained from Hanbio (Shanghai, China). Transfection was carried out according to the manufacturer's protocols. CRC cells were selected by 0.5ug/mL puromycin (Sigma‐Aldrich) 2 weeks post‐transfection. To establish the knockdown model of hsa_circRNA_102209, pooled siRNA targeting hsa_circRNA_102209 (si‐102209) and negative control (si‐NC) were purchased from Genepharm Co. Ltd. The mimics/inhibitors of miR‐761 and corresponding negative control (NC) were synthesized by Genepharm Co. Ltd (Shanghai, China). The mimics/inhibitors (100pM) and siRNA (50 nM) were transfected into CRC cells using Lipofectamine^®2000 (Invitrogen; Thermo Fisher Scientific, Inc.) according to the manufacturer's protocols. The culture medium was replenished with fresh DMEM supplemented with 10% FBS 8 hours post‐transfection. The transfection efficiency was evaluated using RT‐qPCR.