*4.8. Overexpression of LIN28A and LIN28B*

To overexpress *LIN28* genes in iOTR cells, pCDH-LIN28A or pCDH-LIN28B-based lentiviral particles were used to infect iOTR cells at 70–80% confluency in one well of a 12-well plate (Corning Inc., Corning, NY, USA). After 48–72 h, the infected cells were selected using 2–4 µg/mL puromycin. Successful gene knockin was confirmed using real-time PCR and Western blot analysis. We generated

iOTR cells with knockin of LIN28A (AKI) or LIN28B (BKI) and iOTR cells infected with empty-expression vector-based lentiviral particles to use as expression vector control (EVC).
