Fig. 6

Sp1 inhibits CD44 expression in lung cancer. Samples of A549, H1299, E2-A549 and A549-T24 cells with or without Sp1 overexpression or knockdown were used to study the levels of Sp1 and CD44 by Western blotting with the indicated antibodies (A, B). Samples of A549, E2-A549 (C) and A549-T24 (D) cells were used to study the levels of E-cadherin, vimentin, CD44 and β-catenin by Western blotting with the indicated antibodies. The migration (E, F, middle panel) and invasion (E, F, right panel) abilities of A549 cells with or without CD44 knockdown (E) or overexpression (F) were studied by a chamber assay. GFP and GFP-Sp1 were overexpressed in A549 cells with or without E2 treatment and then injected into SCID mice via the tail vein for 5 weeks. Mice were sacrificed for H&E staining (G, a). The level of GFP-Sp1 was studied by Western blotting with an anti-Sp1 antibody (G, b). The tumor area was measured by ImageJ, and a statistical assay was performed (G, c). The results of three independent experiments were quantitated, and statistical analysis was performed with a t test; *p < 0.05, **p < 0.01, ***p < 0.005