Fig. 8.

Activation of ERK is sufficient to prevent multiple lumen formation induced by glucocorticoids. Glandular cultures were infected with vector expression of constitutively active form of MEK1 (CA-MEK1) or the empty vector and grown for 7 days in BIE. (A) Western blot shows increased phosphorylation of ERK in cells infected with CA-MEK1. Membranes were reproved with Myc to ensure expression of the construct and with total ERK and tubulin to ensure equal protein loading. (B) Quantification of single-lumened versus multiple-lumened glands. (C) Representative images of 3D cultures infected with empty vector or vector carrying CA-MEK1 stained with phalloidin (red). Nuclei were evidenced by Hoechst 33342 staining (blue). Scale bars: 50 μm. *P≤0.05.