Claims for Patent: 9,334,527

Summary for Patent: 9,334,527

Title:	Inhibitors of human EZH2, and methods of use thereof
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.
Inventor(s):	Kuntz; Kevin Wayne (Woburn, MA), Knutson; Sarah Kathleen (Cambridge, MA), Wigle; Timothy James Nelson (Waltham, MA)
Assignee:	Epizyme, Inc. (Cambridge, MA)
Application Number:	14/290,642
Patent Claims:	1. A method of treating cancer in a subject in need thereof comprising detecting the presence of a mutation in the EZH2 substrate pocket domain of SEQ ID NO: 7, in a sample from the subject, wherein said detecting comprises screening, at amino acid positions Y641, A677, and A687 of EZH2 of SEQ ID NO: 1, for the presence of at least one mutation, wherein the mutation at amino acid position Y641 is selected from the group consisting of a substitution of phenylalanine (F) for the wild type residue tyrosine (Y) at amino acid position 641 of SEQ ID NO: 1 (Y641F); a substitution of histidine (H) for the wild type residue tyrosine (Y) at amino acid position 641 of SEQ ID NO: 1 (Y641H); a substitution of asparagine (N) for the wild type residue tyrosine (Y) at amino acid position 641 of SEQ ID NO: 1 (Y641N); a substitution of serine (S) for the wild type residue tyrosine (Y) at amino acid position 641 of SEQ ID NO: 1 (Y641S); and a substitution of cysteine (C) for the wild type residue tyrosine (Y) at amino acid position 641 of SEQ ID NO: 1 (Y641C), wherein the mutation at amino acid position A677 is a substitution of glycine (G) for the wild type residue alanine (A) at amino acid position 677 of SEQ ID NO: 1 (A677G), wherein the mutation at amino acid position A687 is a substitution of valine (V) for the wild type residue alanine (A) at amino acid position 687 of SEQ ID NO: 1 (A687V), and wherein the mutation increases EZH2 trimethylation of Lys27 of histone H3 (H3-K27); and identifying the subject as a candidate for treatment with an EZH2 inhibitor based on the presence of a detected EZH2 mutation; administering a therapeutically effective amount of an EZH2 inhibitor to the identified subject, wherein the EZH2 inhibitor inhibits the conversion of H3-K27 to trimethylated H3-K27. 2. The method of claim 1, wherein the nucleic acid encoding SEQ ID NO: 7 is SEQ ID NO: 8. 3. The method of claim 1, wherein the EZH2 inhibitor is a small molecule. 4. The method of claim 1, wherein the cancer is lymphoma, selected from the group consisting of non-Hodgkin lymphoma, follicular lymphoma, diffuse large B-cell lymphoma and diffuse large B-cell lymphoma of germinal center B cell-like subtype. 5. The method of claim 1, wherein the EZH2 inhibitor is selected from the group consisting of ##STR00100## ##STR00101## ##STR00102## ##STR00103## ##STR00104## ##STR00105## ##STR00106## ##STR00107## ##STR00108## ##STR00109## ##STR00110## ##STR00111## ##STR00112## ##STR00113## ##STR00114## ##STR00115## ##STR00116## ##STR00117## or a pharmaceutically acceptable salt thereof. 6. The method of claim 1 wherein the EZH2 inhibitor is ##STR00118## or a pharmaceutically acceptable salt thereof. 7. The method of claim 6, wherein the cancer is lymphoma. 8. The method of claim 7, wherein the lymphoma is non-Hodgkin lymphoma. 9. The method of claim 7, wherein the lymphoma is follicular lymphoma. 10. The method of claim 7, wherein the lymphoma is diffuse large B-cell lymphoma. 11. The method of claim 7, wherein the lymphoma is diffuse large B-cell lymphoma of germinal center B cell-like subtype. 12. The method of claim 2, wherein the EZH2 inhibitor) is ##STR00119## or a pharmaceutically acceptable salt thereof. 13. The method of claim 4, wherein the EZH2 inhibitor is ##STR00120## or a pharmaceutically acceptable salt thereof.