Figure 3

The progression network for squamous cell carcinomas. Gene pairs with significantly correlated expression change and change in expression level >2 standard deviations from mean between skin and carcinomas are drawn as nodes. Red nodes indicate increased expression in carcinomas and green nodes indicate decreased expression, with darker color indicating more extreme change. Grey lines connect genes with significant directly correlated change and blue lines indicate significant inverse correlation. The network demonstrates coordinated increases in gene expression motifs associated with mitosis, stress response, epidermal lineage proliferation, and IL1-mediated inflammatory responses. Concomitant decreases are seen in motifs linked to epithelial cell barrier function, hair follicles, lipid biosynthesis, and muscle cells due to major alterations in cell populations in carcinomas compared to normal skin.