TGF-β1 Downregulates COX-2 Expression Leading to Decrease of PGE2 Production in Human Lung Cancer A549 Cells, Which Is Involved in Fibrotic Response to TGF-β1
Figure 7
Suppressive effect of EP agonists on TGF-β1-induced actin stress fiber formation and migration.
(A) A549 cells were incubated with TGF-β1 (5 ng/mL) and PGE2 (10 µM), vehicle (methyl acetate), sulprostone, butaprost or PGE1-OH (20 µM) for 12 h. Then F-actin was stained using rhodamine phalloidin (red) and stained cells were analyzed using a confocal laser-scanning microscope at x63 magnification. TGF-β1-induced actin stress fiber formation was suppressed by PGE2, butaprost or PGE1-OH. To verify the location of nuclei, cells were stained with Hoechst33258 (blue). (B) Cell migration was examined by Transwell assay as described in Materials and Methods. A549 cells were treated with TGF-β1 (5 ng/mL) and PGE2 (10 µM) for 24 h; then cells were stained and the lower membrane surfaces were photographed through a fluorescence microscope at x20 magnification. Migrated cells were decreased in the presence of PGE2.