Figure 5.

Hierarchical clustering of genes commonly perturbed by smoking across intra- and extrathoracic airway epithelium. A. Supervised hierarchical clustering of the expression of 45 genes induced by smoking in the bronchial airway that are present in both the nasal and buccal "leading edge subsets" in samples from smokers and non-smokers. These represent genes up-regulated by smoking in bronchial, nasal, and buccal epithelium. B. Supervised hierarchical clustering of the expression of 50 genes repressed by smoking in the bronchial airway that are present in the nasal "leading edge subset" in samples from smokers and nonsmokers. (High expression = red, average expression = white, low expression = blue).