Figure 5. Effects of either PI3K or MEK inhibition as well as the antioxidant Trolox on the up-regulation of CAV1 induced by Methotrexate and Etoposide.

Colon cancer (A) HT29(US) and (B) DLD-1 cells were treated with either the PI3K inhibitor LY294002 (LY, 10 μM), the MEK inhibitor PD98059 (PD, 50 μM) or the vitamin E analog, Trolox (TR, 2 mM) for 30 min before treatment with 100 nM Methotrexate (MT) or 10 μM Etoposide (ET) for 48 h. Cells were harvested and total protein extracts were separated by SDS-PAGE (50 μg total protein per lane) and analyzed by Western blotting with antibodies against CAV1 and β-actin. The graphs show the expression of CAV1 normalized to β-actin (mean ± SEM) averaged from 3 independent experiments. Significant differences in comparison with the untreated condition (Basal) are indicated ^***p ≤ 0.001, ^**p ≤ 0.05, ^*p ≤ 0.01.