Altered expressions of proteins related to cell proliferation and apoptosis pathways. A-D, Expressions of proteins related to cell proliferation and apoptosis pathways. KKU-100 with NQO1 knocked down cells were exposed to chemotherapeutic agents; 5-FU (3 μM), Doxo (0.1 μM), and Gem (0.1 μM) for 24 hr. Whole cell lysates were prepared after indicated treatment and Western blot analysis was conducted using anti-p53 (A), -p21 (B), -cyclin D1 (C), -Bax (D) and -β-actin antibodies. The relative bars that were normalized with β-actin as a loading control of each band is shown below the Western blot images. Data represent mean ± SEM, each from three separated experiments. *p < 0.05 vs the treated non-targeting knocked down cells. **p < 0.05 vs the untreated non-targeting knocked down cells.