Fig. 3
Derivative 5 induces vacuolization and ER stress. A: Morphology of MCF-7, PANC-1 and Mia PaCa-2 cells examined under light microscopy (magnification 200x). Cells were treated with DMSO (control) or 1 µg/mL of derivative 5 for 48 h. Enlarged sections of samples treated with 5 are shown in the insets. B: Immunoblots for ER stress markers, BIP, IRE1, and GADD153 in pancreatic cancer cells treated with DMSO or 5 (1 or 5 µg/mL) for 6 or 24 h. The blots were stripped and reprobed with the anti-β-actin antibody to ensure equal protein loading. Densitometric scanning data after correction for loading control (mean of 3 repetitions) are above the immunoreactive bands. C: Relative level of Ca.2+ in pancreatic cancer cells (PANC-1 and Mia PaCa-2) treated with vehicle (DMSO, 100%) or 5 at the indicated concentrations for 12 h. The data are shown as the mean ± SE (n = 7–11). Statistical significance was determined by ANOVA followed by Dunnett’s post hoc test: b—P < 0.001, c—P < 0.05