Abstract: A method for identifying a test compound that has an anti-tumoral effect whilst not significantly activating unrelated transduction signals, the method comprising the steps of: (a) selecting at least one test compound; (b) assaying the compound for anti-tumoral effect; (c) selecting at least one distinct intracellular event which is modulated, at least partially, by the GnRH receptor; (d) testing for the ability of said test compound not to modulate the selected intracellular event; and (e) selecting the test compound which selectively demonstrates an anti-tumoral effect and does not modulate said other selected intracellular event.