Fig. 3

Overexpression of Oct4 enhances Egr1 expression, OPN production, and migratory capability of human lung cancer cells. a and b, H1299 cells (left panel) were transiently transfected with 6 μg of pSin-EF2-Oct4-Pur or the control plasmid pSin-EF2-Pur, and their RNA (a) and protein (b) levels of Oct4 and Egr1 were analyzed at 48 post-transfection by RT-PCR (a) and immunoblot (b) analysis. A549 cells (right panel) stably overexpressing Oct4 and vector control cells were examined for Oct4 and Egr1 expression by RT-PCR (a) and immunoblot (b) analysis. Expression of GAPDH (a) and β-actin (b) served as the loading control. c, The levels of OPN in the supernatants of Oct4-overexpressing and control A549 cells were quantified by ELISA. d, Migratory capabilities of A549-Oct4 and A549-vector cells were detected by a Boyden chamber assay. Cells that migrated through the membrane of the lower surface in the Boyden chamber were stained with Giemsa solution and visualized by light microscopy and photographed (left panel), and three fields in each membrane were counted (right panel). Data are mean ± SEM. **, p < 0.01