Fig. 1

A549 cells are not responsive to SHH stimulation. A. Ligand-induced HH signaling takes place in MEFs, but not in A549 cells. A549 cells and MEFs transfected with 8xGliBS-Luc and pRK-TL were treated with DMSO, Oxy186, Oxy210 or the HH signaling inhibitors SANT-1 or cyclopamine, and stimulated with control CM or SHH CM. After 24 h, Firefly luciferase activity was measured and normalized to Renilla luciferase activity. Data from a representative experiment are reported as the mean of triplicate measurements ± SD (**p < 0.02, *** p < 0.001 vs. SHH CM-treated DMSO control). B Inhibition of A549 cell proliferation by Oxy186 and Oxy210, but not by HH/SMO inhibitor cyclopamine. A549 cell proliferation was measured after treating cells with the indicated compounds in DMEM containing 0.1% FBS for 2 days. Data from a representative experiment are reported as the mean of triplicate measurements ± SD (*** p < 0.001 vs. DMSO control). C. Primary cilia were only sparsely detected in A549 cells. Primary cilia were identified using immunofluorescence as acetylated-α-tubulin-positive axonemes proximal to γ-tubulin-positive basal bodies. Bar = 15 µm. The marked square areas are shown at higher magnification in the merged panels. Ratio of ciliated A549 cells or MEFs at 48 h after serum starvation are shown on the right. Data are reported as the mean from five different fields ± SD