Figure 1.

Activation of Wingless protein (Wnt)/β-catenin signaling in C10 lung epithelial cells after stimulation with Wnt3a or the expression of β-catenin. (A) C10 cells were stimulated with 10 ng/ml Wnt3a, and after 1 hour, nuclear and cytosolic extracts were prepared for the assessment of β-catenin content. Histone H3 and β-actin were used as loading control. Replicate lanes reflect independent samples. Band intensity was determined and expressed as fold increase (fold incr.) of β-catenin over histone H3 or β-actin, respectively. *P < 0.05 (ANOVA), compared with control samples. (B) Activation of T-cell factor/lymphocyte-enhancement factor (TCF/LEF) reporter activity (act.) after stimulation with Wnt3a. C10 cells were transfected with TOP Flash or FOP Flash (0.25 μg) and β-galactosidase (0.25 μg). Twenty-four hours after transfection, cells were stimulated with the indicated concentrations of Wnt3a, and 24 hours afterward were lysed for the assessment of luciferase and β-galactosidase activities. Results are normalized to β-galactosidase, and are expressed as fold increases from sham control samples. *P < 0.05 (ANOVA), compared with control samples. (C) Activation of TCF/LEF reporter activity after the expression of 1 μg wild-type (WT) β-catenin (β-cat), 1 μg S37A β-catenin (β-cat S37A), or 5 ng/ml TGF-β1. Twenty-four hours after transfection with plasmids or stimulation with agents, cells were lysed for the assessment of luciferase and β-galactosidase activities, as described in B. *P < 0.05 (ANOVA), compared with control samples.