Epidermal growth factor receptor inhibitors as tools to suppress three-dimensional tumor growth

Most major cancers are derived from cells that line various human organs (epithelial cells). Normal epithelial cells often form a single layer and detachment from this layer usually causes death of such cells. Conversely, tumors typically grow as three-dimensional disorganized multicellular masses in which many cells are detached from their original location. Such cells, however, instead of dying now live and this viability is required for cancer progression. We, therefore, are investigating how to reverse this resistance to death of tumor cells to cure or slow down the disease. To this end, we plan to find out whether existing anti-cancer drugs block tumor growth, at least in part, by killing cells that grow outside of the original single epithelial layer. We are particularly interested in the recently developed compounds that block the activity of a cellular enzyme called epidermal growth factor receptor. Such activity is elevated in many human cancers and this, according to our studies, is required for the survival of cancer cells inside the disorganized tumor mass. These studies, when completed, could start a new direction of cancer research aimed at the identification of drugs capable of suppressing three-dimensional tumor growth.