Gius and colleagues determined gene expression signatures of cervical carcinogenesis using cDNA microarrays to analyze RNA from laser-captured microdissected epithelium and underlying stroma from normal cervix, graded cervical intraepithelial neoplasia (CIN 1-3), cancer, and patient-matched normal cervical tissues. In this model, the CIN 1 transition coincides with a proproliferative/immunosuppression gene signature in the epithelium that probably represents the epithelial response to HPV infection. The CIN 2 transition coincides with a proangiogenic signature suggesting a cooperative signaling interaction between stroma and tumor cells. Finally, the CIN 3 and squamous cell carcinoma antigen transition coincide with a proinvasive gene signature that may be a response to epithelial tumor cell overcrowding. The yellow and red horizontal line in the middle of the figure represents the basement membrane that separates the epithelium and stromal compartments. Genes coded in dark red represent validated genes with increased expression whereas dark blue represents validated genes with decreased expression. Additional genes are also depicted in the model; gray signifies previously identified host and viral genes, and light red or light blue denotes genes that increase or decrease, respectively, from the microarray data but are not yet validated. For details, see the article by Gius and colleagues on page 7113 of this issue.