Western Blot Analysis of Protein Extracts

Protein samples were obtained from cells lysed with chilled ProEXTM CETi protein extract solution (Translab, Daejeon, Korea). Denatured samples were separated by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Then, the proteins were transferred onto nitrocellulose (NC) membranes (Bio-Rad, Hercules, CA, USA) [30 (link)]. The membranes were incubated overnight at 4 °C with primary antibodies such as anti-PARP, anti-cleaved caspase-3, anti-Bip, anti-CHOP, anti-p-JNK, anti-E-cadherin, anti-N-cadherin (Cell Signaling Technology, Beverly, MA, USA), anti-p53, anti-p21, anti-Bax, anti-Bcl2, anti-GAPDH, anti-β-actin (Santa Cruz Biotechnology, Santa Cruz, CA, USA) and anti-IRE1α (Abcam, Cambridge, MA, USA). After the membranes were incubated for 1 h with the appropriate horseradish peroxidase-conjugated secondary antibodies, the proteins were detected using EZ-Western Lumi Pico (DoGenBio).