# US 8,540,989 B2 · Compositions and methods for treating and diagnosing cancer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,989 B2 - Document ID: US8540989B2 - Status: Granted - Kind: B2 - Application number: 13/408,731 - Filed: 2012-02-29 - Published: 2013-05-16 - Granted: 2013-09-24 - Earliest claimed: 2007-07-02 - Assignees: OncoMed Pharmaceuticals, Inc. - Applicants: Austin Gurney - Inventors: Austin Gurney - Web page: https://patentgrep.com/patent/US8540989B2 ## CPC - A61K 39/39558: {against tumor tissues, cells, antigens} - A61K 39/3955: {against proteinaceous materials, e.g. enzymes, hormones, lymphokines} - A61K 45/06: Mixtures of active ingredients without chemical characterisation, e.g. antiphlogistics and cardiaca - A61P 35/00: Antineoplastic agents - A61P 43/00: Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00 - C07K 14/723: {G protein coupled receptor, e.g. TSHR-thyrotropin-receptor, LH/hCG receptor, FSH receptor} - C07K 16/18: against material from animals or humans - C07K 16/28: against receptors, cell surface antigens or cell surface determinants - C07K 16/30: from tumour cells - A61K 2039/505: {comprising antibodies} - C07K 2317/14: Specific host cells or culture conditions, e.g. components, pH or temperature - C07K 2317/21: from primates, e.g. man - C07K 2317/24: containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered - C07K 2317/76: Antagonist effect on antigen, e.g. neutralization or inhibition of binding - C07K 2319/30: Non-immunoglobulin-derived peptide or protein having an immunoglobulin constant or Fc region, or a fragment thereof, attached thereto - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS - C07K: PEPTIDES (peptides in foodstuffs A23; obtaining protein compositions for foodstuffs, working-up proteins for foodstuffs A23J; preparations for medicinal purposes A61K; peptides containing beta-lactam rings C07D; cyclic dipeptides not having in their molecule any other peptide link than those which form their ring, e.g. piperazine-2,5-diones, C07D; ergot alkaloids of the cyclic peptide type C07D519/02; macromolecular compounds having statistically distributed amino acid units in their molecules, i.e. when the preparation does not provide for a specific; but for a random sequence of the amino acid units, homopolyamides and block copolyamides derived from amino acids C08G69/00; macromolecular products derived from proteins C08H1/00; preparation of glue or gelatine C09H; single cell proteins, enzymes C12N; genetic engineering processes for obtaining peptides C12N15/00; compositions for measuring or testing processes involving enzymes C12Q; investigation or analysis of biological material G01N33/00) ## Abstract The present invention relates to compositions and methods for characterizing, diagnosing and treating cancer. In particular, the present invention identifies LGR5 as a protein over-expressed in solid tumor stem cells. The present invention further identifies an interaction between RSPO1 and LGR5 as an alternative pathway for the activation of beta-catenin signaling. In certain embodiments, the present invention provides biomolecules that disrupt functional signaling via a LGR protein, including, in certain embodiments, molecules that inhibit the interaction between one or more RSPO proteins and one or more LGR proteins, such as LGR5. In certain embodiments, the present invention provides methods of treating cancer comprising disrupting functional LGR signaling and inhibiting growth of a solid tumor comprising solid tumor stem cells. ## Claims ### Claim 1 A method of treating cancer in a subject, comprising administering to the subject a therapeutically effective amount of a monoclonal antibody that specifically binds to a human R-spondin (RSPO) protein, wherein the antibody: (a) disrupts the binding of the RSPO protein to a human leucine-rich repeat-containing G protein-coupled receptor (LGR) protein; and/or (b) disrupts RSPO activation of LGR signaling. ### Claim 2 (depends on 1) The method of claim 1, wherein the RSPO protein is RSPO1. ### Claim 3 (depends on 1) The method of claim 1, wherein the RSPO protein is RSPO2. ### Claim 4 (depends on 1) The method of claim 1, wherein the RSPO protein is RSPO3. ### Claim 5 (depends on 1) The method of claim 1, wherein the RSPO protein is RSPO4. ### Claim 6 (depends on 1) The method of claim 1, wherein the LGR protein is LGR5. ### Claim 7 (depends on 1) The method of claim 1, wherein the LGR protein is LGR4 or LGR6. ### Claim 8 (depends on 1) The method of claim 1, wherein the antibody is a chimeric, humanized, or human antibody. ### Claim 9 (depends on 1) The method of claim 1, wherein the antibody is an antibody fragment. ### Claim 10 (depends on 1) The method of claim 1, wherein the antibody disrupts binding of the RSPO protein to a LGR protein. ### Claim 11 (depends on 1) The method of claim 1, wherein the antibody disrupts RSPO activation of LGR signaling. ### Claim 12 (depends on 1) The method of claim 1, wherein the cancer over-expresses LGR5. ### Claim 13 (depends on 1) The method of claim 1, wherein the cancer is selected from the group consisting of colon cancer, ovarian cancer, breast cancer, lung cancer, and liver cancer. ### Claim 14 (depends on 1) The method of claim 1, further comprising administering to the subject an effective amount of a second anticancer agent. ### Claim 15 (depends on 14) The method of claim 14, wherein the second anticancer agent is a chemotherapeutic agent. ### Claim 16 A method of inhibiting the growth of a tumor in a subject, comprising administering to the subject a therapeutically effective amount of a monoclonal antibody that specifically binds to a RSPO protein, wherein the antibody: (a) disrupts the binding of the RSPO protein to a human LGR protein; and/or (b) disrupts RSPO activation of LGR signaling. ### Claim 17 (depends on 16) The method of claim 16, wherein the RSPO protein is RSPO1. ### Claim 18 (depends on 16) The method of claim 16, wherein the RSPO protein is RSPO2. ### Claim 19 (depends on 16) The method of claim 16, wherein the RSPO protein is RSPO3. ### Claim 20 (depends on 16) The method of claim 16, wherein the RSPO protein is RSPO4. ### Claim 21 (depends on 16) The method of claim 16, wherein the LGR protein is LGR5. ### Claim 22 (depends on 16) The method of claim 16, wherein the LGR protein is LGR4 or LGR6. ### Claim 23 (depends on 16) The method of claim 16, wherein the antibody is a chimeric, humanized, or human antibody. ### Claim 24 (depends on 16) The method of claim 16, wherein the antibody is an antibody fragment. ### Claim 25 (depends on 16) The method of claim 16, wherein the antibody disrupts binding of the RSPO protein to a LGR protein. ### Claim 26 (depends on 16) The method of claim 16, wherein the antibody disrupts RSPO activation of LGR signaling. ### Claim 27 (depends on 16) The method of claim 16, wherein the tumor over-expresses LGR5. ### Claim 28 (depends on 16) The method of claim 16, wherein the tumor is selected from the group consisting of a colon tumor, an ovarian tumor, abreast tumor, a lung tumor, and a liver tumor. ### Claim 29 (depends on 16) The method of claim 16, further comprising administering to the subject an effective amount of a second anticancer agent. ### Claim 30 (depends on 29) The method of claim 29, wherein the second anticancer agent is a chemotherapeutic agent.