Provided herein are nucleic acids, proteins, vectors, cells, kits, devices and methods useful for identifying regulatable proteins that are able to complement components of cellular signaling pathways. Also provided are compositions and methods using these complementing genes directly as markers for cancer diagnosis or prognosis and as targets for anti-neoplastic therapeutics. Further provided are methods for using changes caused by expression of the complementing genes to indirectly identify associated genes to be used as markers for cancer diagnosis or prognosis and as targets for anti-neoplastic therapeutics.