Inhibitors of human EZH2, and methods of use thereof

• US 9,949,999 B2
• Filed: 04/19/2016
• Issued: 04/24/2018
• Est. Priority Date: 09/10/2010
• Status: Active Grant

• Current Assignee: Epizyme, Inc. (Ipsen Sa)
• Original Assignee: Epizyme, Inc. (Ipsen Sa)
• Inventors: Copeland, Robert A., Richon, Victoria M., Scott, Margaret D., Sneeringer, Christopher J., Kuntz, Kevin W., Knutson, Sarah K., Pollock, Roy M.
• Primary Examiner(s): Leith, Nancy J
• Application Number:
  US15/132,724
• Publication Number:
  US 20170065628A1
• Time in Patent Office: 735 Days
• Field of Search: None
• CPC Class Codes: A61K 31/7076 containing purines, e.g. adenosine, adenylic acid
• CPC Class Codes: A61P 35/00 Antineoplastic agents
• CPC Class Codes: A61P 35/02 specific for leukemia
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00
• CPC Class Codes: C07D 473/34 attached in position 6, e.g. adenine
• CPC Class Codes: C07D 493/04 Ortho-condensed systems
• CPC Class Codes: C12Q 1/48 involving transferase
• CPC Class Codes: C12Q 1/6876 Nucleic acid products used in the analysis of nucleic acids, e.g. primers or probes
• CPC Class Codes: G01N 2333/91011 Methyltransferases (general) (2.1.1.)
• CPC Class Codes: G01N 33/5011 for testing antineoplastic activity
• CPC Class Codes: G01N 33/57426 leukemia

Abstract

The invention relates to inhibition of wild-type and certain mutant forms of human histone methyltransferase EZH2, the catalytic subunit of the PRC2 complex which catalyzes the mono- through tri-methylation of lysine 27 on histone H3 (H3-K27). In one embodiment the inhibition is selective for the mutant form of the EZH2, such that trimethylation of H3-K27, which is associated with certain cancers, is inhibited. The methods can be used to treat cancers including follicular lymphoma and diffuse large B-cell lymphoma (DLBCL). Also provided are methods for identifying small molecule selective inhibitors of the mutant forms of EZH2 and also methods for determining responsiveness to an EZH2 inhibitor in a subject.

Claims

1. A method of inhibiting Enhancer of Zeste Homolog 2 (EZH2), the method comprising contacting a cell expressing a Y641 mutant of the EZH2 polypeptide of SEQ ID NO:

1, a Y646 mutant of the EZH2 polypeptide of SEQ ID NO;

3, or a Y602 mutant of the EZH2 polypeptide of SEQ ID NO;

5 with an inhibitor of EZH2 in an amount effective to inhibit the conversion of H3-K27 to trimethylated H3-K27 in the cell.

2. The method of claim 1, wherein the inhibition is selective inhibition.

3. The method of claim 1, wherein the Y641 mutant of the EZH2 polypeptide is a Y641F mutation.

4. The method of claim 1, wherein the Y641 mutant of the EZH2 polypeptide is a Y641H mutation.

5. The method of claim 1, wherein the Y641 mutant of the EZH2 polypeptide is a Y641N mutation.

6. The method of claim 1, wherein the Y641 mutant of the EZH2 polypeptide is a Y641S mutation.

7. The method of claim 1, wherein the cell expressing the Y641 mutant of the EZH2 polypeptide is a cancer cell.

8. The method of claim 7, wherein the cancer cell is a lymphoma cell.

9. The method of claim 8, wherein the lymphoma is a B-cell lymphoma.

10. The method of claim 8, wherein the lymphoma is follicular lymphoma.

11. The method of claim 8, wherein the lymphoma is diffuse large B-cell lymphoma (DLBCL).

12. The method of claim 7, wherein the cancer cell is a melanoma cell.

13. The method of claim 1, wherein the cell expressing the Y641 mutant of the EZH2 polypeptide is a cell obtained from a subject.

14. The method of claim 1, wherein the method further comprises obtaining the cell expressing the Y641 mutant of the EZH2 polypeptide from a subject.

15. The method of claim 1, wherein the cell expressing the Y641 mutant of the EZH2 polypeptide is a cell of a subject having cancer.

16. The method of claim 15, wherein the subject is a human subject.

17. The method of claim 15, wherein the contacting comprises administering the EZH2 inhibitor to the subject.