Figure 6

Immunoblot analysis of activated ERK (p-ERK) or total ERK level upon TPA treatment. (A) K562 cells were treated with 5 nM TPA for various times (5–30 min). (B) K562/D2, K562/D3 or the control K562/vector cells (two lanes for each stable clone) were treated with 5 nM TPA for 10 min. Cells were harvested and 20 μg of total cellular proteins was separated by 10% SDS–PAGE and blotted onto PVDF membrane. p-ERK, ERK (total) or β-actin protein were detected by Western blot using anti-p-ERK, ERK or β-actin monoclonal antibody and the ECL reaction.