Protein Extraction and Antibody Analysis

Following protein extraction, equal amounts of protein were separated using 8–15% sodium dodecyl sulphate-polyacrylamide gel electrophoresis [20 (link)]. Antibodies against COL11A1 (GTX55142), DNMT1 (GTX116011), DNMT3A (GTX129125), and DNMT3B (GTX129127) were obtained from GeneTex (Irvine, CA, USA). An anti-β-actin antibody (sc-47778) was purchased from Santa Cruz Biotechnology (Dallas, TX, USA), whereas antibodies against Akt (9272), phospho-Akt (Ser473, 9271), ubiquitin (58395), mouse IgG (7076), and rabbit IgG (7074) were obtained from Cell Signaling Technology (Danvers, MA, USA). An antibody against phospho-DNMT1 (Ser84) was purchased from Affinity Biosciences (Melbourne, Australia). An antibody against phospho-DNMT1 (Ser154) was purchased from Bioss Antibodies (Woburn, MASS, USA). An antibody against SUMO-3 was purchased from Abcam (Cambridge, UK). An antibody against p16 (AF5484) was purchased from Affinity Biosciences (Bath, UK). 5-aza-2′-deoxycytidine (5-aza) and MG132 were obtained from Sigma-Aldrich. Cisplatin (Fresenius Kabi Oncology, Ltd.) was provided by the Cancer Center of National Cheng Kung University Hospital.