Invasive tumors induce c-ets1 transcription factor expression in adjacent stroma.

The stroma reaction plays a central role in tumor growth, invasion and metastasis. Tumor growth is dependent on angiogenesis and requires the vascular supply provided by new capillary blood vessels of the stroma. The expression of the gene encoding the transcription factor c-ets1 is localized within fibroblasts and endothelial cells of the stromal compartment. This expression correlates with the accumulation of transcripts for potential target genes such as collagenase I and stromelysin I in stromal fibroblasts surrounding malignant cells in invasive tumors. We suggest that c-Ets1 protein might regulate the transcription of the genes coding for matrix-degrading proteases necessary for both angiogenesis and tumor invasion.