Fig. 4. MEK5 and ERK5 inhibitors reduced cell proliferation of lung cancer cells.
a H460 cells were treated with increasing doses of BIX02189 for 72 h and the effect of the drug on ERK5 activation was evaluated by immunoprecipitation of 1 mg of whole-cell lysates and western blotting with the anti-ERK5 or anti-pERK5TEY antibodies. pS6 and pERK1/2 were used as controls to assure that BIX02189 did not affect the PI3K and ERK1/2 routes. GAPDH was used as loading control. b Quantitation of pERK5 band in H460 cells from (a) using the ImageJ software. Data represent the percentage of the upper pERK5 band after BIX02189 treatment with respect to such band in control H460 untreated cells. c NSCLC cells were plated in 24-well dishes and treated with increasing doses of BIX02189. Cell proliferation was measured at the indicated times by MTT. Results are expressed as mean ± SD of an experiment that was repeated three times. *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001. The exact p-values are shown in Supplementary Table 1a. d H460 cells were treated with increasing doses of JWG-071 for 7 h. Inhibition of ERK5 activation was evaluated by immunoprecipitation of 1.3 mg of whole-cell lysates with the anti-ERK5 antibody and probed with the C terminal anti-ERK5 or anti-pERK5TEY antibodies. pS6 and pERK1/2 were used as controls to assure that JWG-071 did not affect the PI3K and ERK1/2 routes. GAPDH was used as loading control. e Quantitation of pERK5 bands was performed as in (b). f NSCLC cells were plated in 24-well dishes and treated with increasing doses of JWG-071. Cell proliferation was measured at the indicated times by MTT. Results are expressed as mean ± SD of an experiment that was repeated three times. *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001. The exact p-values are shown in Supplementary Table 1b.