*2.1. Antibodies and Reagents*

Anti-CD44, anti-phospho-AKT, anti-AKT, anti-phospho-ERK, anti-ERK1/2, anti-phosphop38, anti-p38, anti-phospho-SAPK/JNK, and anti-JNK1/2 antibodies were purchased from Cell Signaling Technology (Cambridge, MA, USA). Anti-phospho-JNK, anti-Oct3/4 and anti-β-actin were obtained from Santa Cruz Biotechnology (Santa Cruz, CA, USA). Anti-SOX2, anti-Notch2, and anti-Snail were purchased from Abcam (Cambridge, MA, USA). Anti-β-catenin was procured from BD Bioscience (Franklin Lakes, NJ, USA). For transfection, non-targeting siRNA and commercial siRNA for SOX2 or Snail or AKT were purchased from Genolution (Genolution Pharmaceuticals, Seoul, Korea). The cells were transfected with each siRNA (50 nM) for 48 h using Lipofectamine 2000 (Invitrogen, Carlsbad, CA, USA), as described in the manufacturer's procedure.
