Methods for the identification of agents that inhibit mesenchymal-like tumor cells or their formation

Abstract

The present invention provides tumor cell preparations for use as models of the EMT process for use in the identification of anti-cancer agents, wherein said tumor cell preparations comprise cells of the epithelial tumor cell line H1650, which are stimulated by receptor ligands to induce EMT, or which have been engineered to inducibly express a protein that stimulates EMT. The present invention also provides methods of identifying potential anti-cancer agents by using such tumor cell preparations to identify agents that inhibit EMT, stimulate MET, or inhibit the growth of mesenchymal-like cells. Such agents should be particularly useful when used in conjunction with other anti-cancer drugs such as EGFR and IGF-1R kinase inhibitors, which appear to be less effective at inhibiting tumor cells that have undergone an EMT.

1 .- 41 . (canceled) 
     
     
         42 . A mesenchymal-like tumor cell preparation for use in the identification of anti-cancer agents, wherein said tumor cell preparation is prepared by a process comprising:
 contacting a sample of cells of the epithelial tumor cell line H1650 with a single or dual protein ligand preparation to induce an epithelial-to-mesenchymal transition in the H1650 cells,   wherein the single protein ligand that induces an epithelial-to-mesenchymal transition in H1650 cells is selected from any of the protein ligands that bind to and activate the EGF receptor or the HGF receptor, and   wherein the dual protein ligands that induce an epithelial-to-mesenchymal transition in H1650 cells are a protein ligand that binds to a receptor that activates the signal transduction pathways activated by the binding of oncostatin M to its receptor or a protein ligand that binds to a receptor that activates the signal transduction pathways activated by the binding of TGF-beta to its receptor, plus one ligand that binds to the TNFα receptor and activates the same signal transduction pathways that are activated by the binding of TNFα to its receptor.   
     
     
         43 . The cell preparation of  claim 42 , wherein the single protein ligand that induces an epithelial-to-mesenchymal transition in H1650 cells is selected from, EGF, TGF-α, HB-EGF, amphiregulin, betacellulin, epiregulin, epigen, and HGF. 
     
     
         44 . The cell preparation of  claim 43 , wherein the single protein ligand that induces an epithelial-to-mesenchymal transition in H1650 cells is selected from EGF and HGF. 
     
     
         45 . The cell preparation of  claim 44 , wherein the single protein ligand that induces an epithelial-to-mesenchymal transition in H1650 cells is EGF, optionally supplemented with TNF-α. 
     
     
         46 . The cell preparation of  claim 44 , wherein the single protein ligand that induces an epithelial-to-mesenchymal transition in H1650 cells is HGF, optionally supplemented with EGF, TGF-beta, TNF-α, or OSM. 
     
     
         47 . The cell preparation of  claim 42 , wherein the dual protein ligands that induce an epithelial-to-mesenchymal transition in H1650 cells are oncostatin-M plus TNFα, or TGF-beta plus TNFα. 
     
     
         48 . The cell preparation of  claim 42 , wherein TGF-beta is TGFbeta-1, TGFbeta-2, TGFbeta-3, or heterodimers thereof. 
     
     
         49 - 93 . (canceled)