Abstract: The present invention relates generally to methods of modulating the rate and/or amount of a cellular process selected from the group consisting of cell growth, cell detachment and cell migration, and cellular apoptosis, said method comprising altering the RECEPTOR/PTK-STAT pathway of a cell. More particularly, the present invention relates to methods wherein the RECEPTOR/PTK-STAT pathway is altered by increasing or decreasing the amount of phosphorylated RECEPTOR/PTK-STAT proteins present in a cell. The present invention also relates to the identification of agents that either promote or inhibit the phosphorylation of RECEPTOR/PTK-STAT proteins, as well as to the agents themselves and to the methods which utilize such identified agents. The methods of the present invention are useful for treating mammalian diseases, including, but not limited to, cancer, autoimmune diseases, viral susceptibility, degenerative disorders, ischemic injuries, and conditions of obesity.