- Interleukin-1alpha protein secretion in breast cancer is associated with poor differentiation and estrogen receptoralpha negativity. Singer, C.F., Hudelist, G., Gschwantler-Kaulich, D., Fink-Retter, A., Mueller, R., Walter, I., Czerwenka, K., Kubista, E. Int. J. Gynecol. Cancer (2006)