Novel tissue protective erythropoietin receptor (nepor) and methods of use

Abstract

There is disclosed a molecular composition(s) of a novel tissue protective erythropoietin (EPO) binding receptor protein complex, termed NEPOR. Presence of NEPOR components on a tumour allows EPO to impinge on the survival of associated cells thereby enhancing tumour progression and negatively effecting patient survival. Presence of NEPOR represents a prognostic biomarker for poorer patient outcome. Thus, methods are provided for stratifying patients having a tumour as suitable (i.e. NEPOR not present) or non-suitable (i.e., NEPOR present) for EPO treatment, comprising: (a) isolating a tissue sample from an individual who is receiving or is a candidate for receiving erythropoietin, (b) determining the level of expression of the NEPOR gene(s) (mRNA) and/or the presence of the NEPOR gene product (protein) from the isolated tissue, and (c) correlating the presence of an NEPOR gene expression product or the presence of NEPOR protein to a physiological response to the treatment with erythropoietin. Furthermore, by disclosing the molecular compositions of NEPOR species, there are disclosed methods for rationally identifying/designing NEPOR modulating therapeutics. Methods also are provided for treating neurological insults such as stroke (via enhancement of NEPOR activity) and cancer (via down-regulation of cyto-protective signaling from NEPOR).

1 - 21 . (canceled) 
     
     
         22 . A method of treating a cancer patient, comprising:
 (A) obtaining a cancer tissue sample from a cancer patient who is a candidate for erythropoietin (EPO) therapy;   (B) measuring EPH-B4 expression in said sample; and   (C) administering EPO therapy to said patient when EPH-B4 expression in said sample is not elevated.   
     
     
         23 . The method of  claim 22 , wherein measuring EPH-B4 expression in said sample is effected by a molecular biological technique. 
     
     
         24 . The method of  claim 22 , wherein measuring EPH-B4 expression in said sample is effected by detecting the presence and/or amount of EPH-B4 mRNA in said sample. 
     
     
         25 . The method of  claim 24 , wherein detecting the presence and/or amount of EPH-B4 mRNA in said sample is effected by one or more techniques selected from the group consisting of PCR, RT-PCR, QPCR, R-PCR, gene expression microarray analysis, northern-blot analysis, reverse transcription and amplification, zymography, ligase-chain-reaction, nucleic acid sequence-based amplification (NASBA), RNase protection assay (RPA), and capillary electrophoresis with laser induced fluorescence (CE-LIF). 
     
     
         26 . The method of  claim 22 , wherein measuring EPH-134 expression in said sample is effected by detecting the presence and/or amount of EPH-B4 protein in said sample. 
     
     
         27 . The method of  claim 26 , wherein detecting the presence and/or amount of EPH-B4 protein in said sample is effected by one or more techniques selected from the group consisting of immunoprecipitation, enzyme immunoassay (EIA), radioimmunoassay (RIA), fluorescent immunoassay, chemiluminescent assay, agglutination assay, nephelometric assay, turbidimetric assay, Western blot, competitive immunoassay, noncompetitive immunoassay, homogeneous immunoassay, heterogeneous immunoassay, bioassay, reporter assay, protein array assay, and binding to a mass microbalance instrument. 
     
     
         28 . The method of  claim 26 , wherein detecting the presence and/or amount of EPH-B4 protein in said sample is effected by immunohistochemistry. 
     
     
         29 . The method of  claim 26 , wherein detecting the presence and/or amount of EPH-B4 protein in said sample is effected by ELISA. 
     
     
         30 . The method of  claim 22 , wherein elevated EPH-B4 expression is relative to a baseline level of EPH-B4 expression. 
     
     
         31 . The method of  claim 22 , wherein elevated EPH-B4 expression is relative to EPH-B4 expression in non-cancerous cells or tissue. 
     
     
         32 . The method of  claim 22 , wherein said sample is selected from cancerous tissue or circulating cells derived from cancerous tissue. 
     
     
         33 . The method of  claim 22 , wherein said sample is selected from the group consisting of blood, lymph, urine and cerebral fluid. 
     
     
         34 . The method of  claim 22 , wherein said sample is a tumor biopsy sample. 
     
     
         35 . The method of  claim 22 , further comprising measuring the presence and/or amount of Ephrin A1 in said sample. 
     
     
         36 . The method of  claim 22 , further comprising measuring the presence and/or amount of EPOR in said sample. 
     
     
         37 . A method of treating a cancer patient, comprising administering erythropoietin (EPO) to a cancer patient identified as not exhibiting elevated levels of EPH-B4 expression. 
     
     
         38 . A method of administering EPO to a cancer patient in need thereof, comprising:
 (A) obtaining a cancer tissue sample from a cancer patient who is a candidate for erythropoietin (EPO) therapy;   (B) measuring EPH-B4 expression in said sample; and   (C) administering EPO to said patient if EPH-B4 expression in said sample is not elevated.   
     
     
         39 . A method comprising:
 (A) obtaining a cancer tissue sample from a cancer patient who is a candidate for erythropoietin (EPO) therapy;   (B) measuring EPH-B4 expression in said sample; and   (C)(i) identifying said patient as being at risk of a negative outcome of EPO therapy when EPH-B4 expression in said sample is elevated; or   (C)(ii) identifying said patient as being a candidate for (EPO) therapy when EPH-B4 expression in said sample is not elevated.   
     
     
         40 . A method comprising:
 (A) obtaining a cancer tissue sample from a cancer patient who is a candidate for erythropoietin (EPO) therapy;   (B) measuring EPH-B4 expression in said sample; and   (C)(i) identifying said patient as being at risk of a negative outcome of EPO therapy when EPH-B4 expression in said sample is elevated; or   (C)(ii) identifying said patient as being a candidate for (EPO) therapy when EPH-B4 expression in said sample is not elevated;   wherein, if said patient is identified in (C)(ii) as being a candidate for EPO therapy, EPO is administered to said patient.   
     
     
         41 . A method comprising:
 (A) obtaining a cancer tissue sample from a cancer patient who has received erythropoietin (EPO) therapy;   (B) measuring EPH-B4 expression in said sample; and   (C) correlating said patient's risk of a negative outcome of EPO therapy with the level of EPH-B4 expression in said sample.