The most devastating aspect of cancer is the ability of tumor cells to migrate to other sites and establish new colonies or metastases. We have characterized the molecules, both RNA and protein, that are found in the pseudopodia and that are critical to the ability of tumor cells to migrate. Certain of these were found to be required to change the phenotype of metastatic cancer cells from an epithelial phenotype (in which cells are closely attached one to the other) to a mesenchymal phenotype (in which cells separate from and migrate away from one another). The importance of the identified pseudopod proteins to promote what is called epithelial to mesenchymal transition suggests that they may be possible targets for anti-metastasis therapy.