4.5. Western Blot Analysis

The experimental process followed the protocols described by Chen et al. with modification [25]. B16-F10 and SK-MEL-2-Luc cells were treated with a single treatment of VPA or ETO, simultaneous and sequential combined treatments of VPA and ETO. The chemiluminescent signals of individual protein were recorded on films (Fujifilm, Tokyo, Japan) for analysis. Some membranes were intensified for their chemiluminescent signals of individual protein by Amersham ECL Prime Western Blotting Detection Reagent (GE Healthcare, Chicago, IL, USA) and then recorded the signals by Luminescence/Fluorescence Imaging System (GE Healthcare, Chicago, IL, USA; Life Sciences ImageQuant; LAS 4000). The anti-Ku80/KU80 (Cat. #2180), Ku70/KU70 (Cat. #4588), Chk2/CHK2 (Cat. #2662), p53 (Cat. #2524 for B16-F10 cells; Cat. #9282 for SK-MEL-2-Luc cells), Rad51/RAD51 (Cat. #8875), p21 (Cat. #64016 for B16-F10 cells; Cat. #2947 for SK-MEL-2-Luc cells), and γH2AX (Cat. #9718) antibodies were obtained from Cell Signaling Technology (Danvers, MA, USA). The GAPDH (Cat. #GTX627408) antibody was obtained from GeneTex (Irvine, CA, USA).