Preparation of HCT116 cell lysate. HCT116 cells were cultured in 6-well cell culture plate to about 90% confluency. The DMEM culture medium was removed, and cells were washed with 1 mL Dulbecco's phosphate-buffered saline (DPBS) twice. After washing, 600 L cell lysis buffer (10 mM Tris-HCl buffer, 50 mM KCl, 1.5 mM MgCl2, 0.45% Tween 20 and 0.45% Triton X-100, pH 8.5) was added to the each well, followed by vibration at 400 rpm for 5 min. The mixture was collected and centrifuged at 8000 rpm for 5 min. The supernatant was collected, and the protein was quantitated by Pierce TM BCA protein assay kit (Thermo Fisher Scientific).