Aberrations of EZH2 in Cancer

Published OnlineFirst March 2, 2011; DOI: 10.1158/1078-0432.CCR-10-2156

Clinical Cancer Molecular Pathways Research

Andrew Chase and Nicholas C.P. Cross

Abstract Control of gene expression is exerted at a number of different levels, one of which is the accessibility of genes and their controlling elements to the transcriptional machinery. Accessibility is dictated broadly by the degree of chromatin compaction, which is influenced in part by polycomb group proteins. EZH2, together with SUZ12 and EED, forms the polycomb repressive complex 2 (PRC2), which catalyzes trimethylation of histone H3 lysine 27 (H3K27me3). PRC2 may recruit other polycomb complexes, DNA methyltransferases, and histone deacetylases, resulting in additional transcriptional repressive marks and chromatin compaction at key developmental loci. Overexpression of EZH2 is a marker of advanced and metastatic disease in many solid tumors, including prostate and breast cancer. Mutation of EZH2 Y641 is described in lymphoma and results in enhanced activity, whereas inactivating mutations are seen in poor prognosis myeloid neoplasms. No histone demethylating agents are currently available for treatment of patients, but 3-deazaneplanocin (DZNep) reduces EZH2 levels and H3K27 trimethylation, resulting in reduced cell proliferation in breast and prostate cancer cells in vitro. Furthermore, synergistic effects are seen for combined treatment with DNA demethylating agents and histone deacetylation inhibitors, opening up the possibility of refined epigenetic treatments in the future. Clin Cancer Res; 17(9); 2613–8. 2011 AACR.

Background trithorax homolog myeloid-lymphoid leukemia (MLL), is associated with transcriptional activation (Fig. 1A). Impor- DNA is wrapped around histone complexes termed tantly, many genes involved in development, stem cell nucleosomes, and gene accessibility is determined largely maintenance, and differentiation are targets of H3K27 by the local chromatin configuration. This configuration and H3K4 methylation. In embryonic (1, 2) and hemo- may impact on the ability of cofactors and enhancers to poietic (3) stem cells (HSC), promoters may carry both bind specific DNA sequences, either via direct interactions marks, termed a "bivalent" domain, and genes thus marked with nucleosome components or, more generally, by influ- are thought to be poised for transcriptional activation or encing the degree to which DNA and/or nucleosome com- repression with loss of H3K27 or H3K4 methylation, plexes are compacted into higher structures and, thus, the respectively. physical accessibility of specific recognition sequences. H3K27 methylation is catalyzed by the SET domain of Local chromatin structure is influenced, in part, by histone EZH2 and requires the presence of 2 additional proteins, usage but principally by covalent modifications to histone embryonic ectoderm development (EED) and suppressor tails and DNA methylation. Both PcG and Trx proteins play of zeste 12 (SUZ12). These proteins, together with the important roles in this process by modifying lysine residues histone binding proteins retinoblastoma binding protein within histone tails, resulting in repression or enhance- 4 (RBBP4) and RBBP7, comprise the core components of ment of transcription. the polycomb repressive complex 2 (PRC2; Fig. 1B). Other Two histone modifications, in particular, play crucial proteins such as PHD finger protein 1 (PHF1), which opposing roles in the epigenetic control of proliferation specifically stimulates H3K27 trimethylation rather than and differentiation. Trimethylation of histone H3 lysine 27 dimethylation (4), sirtuin 1 (SIRT1; ref. 5), and jumonji, AT (H3K27me3), catalyzed by the PcG enhancer of zeste rich interactive domain 2 (Jarid2; refs. 6, 7) have also been homolog 2 (EZH2), is associated with transcriptional described in PRC2 complexes and probably serve modulat- repression, whereas H3K4 methylation, catalyzed by the ing functions. A second polycomb complex, PRC1, catalyzes ubiquitination of histone H2A K119, which is also associated with a repressive chromatin structure. PRC1 Authors' Affiliation: Wessex Regional Genetics Laboratory, Salisbury, consists of several proteins including chromobox homolog and Human Genetics Division, University of Southampton Faculty of 2 (CBX2) or related homologs, which bind H3K27me3, Medicine, Southampton, United Kingdom ring finger protein 1A (RING1A), or RING1B, which cat- Corresponding Author: Andrew Chase, Wessex Regional Genetics Laboratory, Salisbury District Hospital, Salisbury SP2 8BJ, United King- alyze ubiquitination and BMI1 polycomb ring finger onco- dom. Phone: 44-1722 336262; Fax: 44-1722 338095; E-mail: gene (BMI1) or polycomb group ring finger 6/Mel18 [email protected] (PCGF2), which modulate ubiquitination activity. doi: 10.1158/1078-0432.CCR-10-2156 According to the hierarchical model of PRC recruitment 2011 American Association for Cancer Research. first developed through genetic studies in Drosophila (8),

www.aacrjournals.org 2613

Chase and Cross

A PRC2

H3K27 H3K27 H3K27 me me me Transcriptional repression X B

MLL SUZ12 EED RBBP4/7

Transcriptional activation EZH2

PolycombPolycomb represrepressivessive me me me complexcomplex (PRC2)(PRC H3K4 H3K4 H3K4 H3K27 H3K27 H3K27 me me me Bivalent domain with low level transcription Gene poised for later me me me activation or repression H3K4 H3K4 H3K4

C PRC2

H3K27 H3K27 H3K27 H3K27 me me me me

Chromatin compaction ub me H2KH2K119119 CytosineCyty osine aacc aac X Repression of targets e.g. HDAC PRC1 DNMT developmental and H2A DNA HHistoneistone differentiation genes uubiquitinationbiquitination metmethylationhylation ddeacetylationeacetylation

D DZNep

MethionineMethionine MethionineMethionine cyclecycle cyclecycle H3K27 H3K277 me3 me3 X PRC2 PRC2

Figure 1. A, PRC2 catalyzes H3K27me associated with transcriptional repression, whereas myeloid-lymphoid leukemia catalyzes methylation of H3K4 associated with transcriptional activation. In bivalent domains, both marks are present and associated with a low level of transcription; genes thus marked are thought to be poised for later transcriptional repression or activation. B, the PRC2 core components are EZH2, SUZ12, EED, and RBBP4 or RBBP7. C, PRC2 is recruited to DNA, resulting in H3K27me3. This mark facilitates recruitment of PRC1, which ubiquitinates H2AK119, DNMT, and HDACs, which contribute to chromatin compaction and transcriptional repression. D, Levels of EZH2 and H3K27me3 can be indirectly reduced by treatment with DZNep, resulting in transcriptional derepression.

2614 Clin Cancer Res; 17(9) May 1, 2011 Clinical Cancer Research

Aberrations of EZH2 in Cancer

PRC2 is first recruited to target genes and catalyzes methy- anchorage-independent colony growth and promotion of lation of H3K27. This step is followed by recruitment of invasion in vitro by overexpression of EZH2 in the breast PRC1 and ubiquitination of H2AK119 (Fig. 1C). This epithelial cell line H16N2 (25). In addition, ectopic EZH2 model would predict that targets of PRC1 and PRC2 largely increased the proliferation of mouse embryonic fibroblasts overlap, as has indeed been shown by RNA interference (33). (RNAi) depletion studies in human embryonic fibroblasts A remarkable connection has been described between (9). In HSCs, however, there is evidence for opposing roles PRC2 occupancy and the aberrant methylation of CpG for PRC1 and PRC2 (10–13). BMI1 is required for HSC islands at promoters seen in some cancers (34–36). Pro- repopulation (10, 12), whereas reduced levels of Suz12, moters found to have aberrant CpG island hypermethyla- Ezh2, or Eed result in increased HSC-progenitor proliferation were also found to be enriched for PRC2 and H3K27 tion (13). In addition, genes known to be repressed by methylation. These sites were also found to be precisely CCAAT/enhancer binding protein alpha (CEBPA) or acti- those occupied by PRC2 in stem cells. Because PRC2 can vated by homeobox A9 (HoxA9) have been found to be recruit DNMTs (19), it seems that PRC2 may act as a differentially regulated by PRC1 and PRC2 (13). It is platform for aberrant de novo promoter methylation, currently not known whether the differential effects of although the precise contexts in which this occurs is still PRC1 and PRC2 seen in HSC also occur in other tissues. unclear. Although PRC2 in Drosophila is recruited to defined Polycomb Response Elements upstream of target genes, EZH2 mutations similar motifs have not been identified in vertebrates. It has Recent work has identified acquired EZH2 mutations in been suggested that recruitment may occur via intermedi- lymphoma and myeloid neoplasms. In lymphoma, a het- ary molecules, with evidence for involvement of the long erozygous missense mutation at amino acid Y641, within noncoding RNA hox transcript antisense RNA (HOTAIR; the SET domain, was initially identified by high throughput refs. 14, 15), nuclear inhibitor of protein Ser/Thr phospha- transcriptome sequencing. Various heterozygous muta- tase-1 (NIPP1; ref. 16), Pho repressive complex (PhoRC; tions at Y641 were subsequently found in 7% of follicular refs. 8, 17), and Jarid2 (18). lymphomas and 22% of diffuse large cell B-cell lymphomas It is clear that activating and repressive histone methyla- of germinal center origin (37). Mutations elsewhere in tion marks do not act in isolation but are intimately EZH2 were not seen. Although initially thought to result coordinated with the action of other epigenetic modifica- in a loss of catalytic activity, more detailed analysis showed tions (Fig. 1C). EZH2 can bind the DNA methyltransferases that Y641 mutants actually result in a gain of function. DNMT1, DNMT3A, and DNMT3B (19), which can result in Specifically, normal EZH2 displays greatest catalytic activity DNA methylation, at least in certain circumstances (20). for monomethylation of H3K27 and relatively weak effi- Knockdown of EZH2 can result in reexpression of genes ciency for the subsequent (mono- to di- and di- to tri- with H3K27 methylation and minimal DNA methylation methylation) reactions. Remarkably, Y641 mutants display but not genes that are hypermethylated (21). Recruitment very limited ability to do the first methylation reaction but of histone deacetylase (HDAC) proteins by PRC2 has been have enhanced catalytic efficiency for the subsequent reac- suggested as a further mechanism for transcriptional tions (38). Heterozygous Y641 mutants, thus, work in repression. PRC2 can bind HDAC via EED (22), and conjunction with wild-type EZH2 to increase levels of treatment of nonerythroid cells with the HDAC inhibitor H3K27me3 and may be functionally equivalent to EZH2 trichostatin A results in depletion of PRC2 and induction of overexpression. a-globin expression, a locus that is normally tightly In myeloid neoplasms, mutations have been described repressed and marked by hypoacetylation and the presence largely in poor prognosis myelodysplasia-myeloprolifera- of PRC2 and H3K27me3 (23). tive neoplasms (10 to 13%), myelofibrosis (13%), and various subtypes of myelodysplastic syndromes (6%; refs. EZH2 and cancer 39, 40). In contrast to the mutation of a single residue and Overexpression of EZH2 was first linked to cancer by gain of function seen in lymphoma, mutations were spread microarray studies of prostate cancer (24) and breast cancer throughout the gene and comprised missense, nonsense, (25). In prostate cancer, EZH2 overexpression is associated and premature stop codons, some of which were homo- with aggressive and metastatic disease. Similarly in breast zygous. Because the catalytic SET domain lies at the far C cancer, EZH2 expression is elevated in invasive carcinoma terminus, all nonsense and stop codon mutations would be and metastases, and increased expression is strongly asso- predicted to result in loss of histone methyltransferase ciated with a poor clinical outcome (25). Overexpression of activity and, thus, are clearly different functionally from EZH2 has also been described in other cancers including Y641 mutants. The fact that both activating and inactivat- bladder (26–28), gastric (29), lung (30), and hepatocel- ing mutations of EZH2 are associated with malignancy is lular carcinoma (31). Deletions of microRNA-101, a nega- remarkable and reflects the complex role that PcG genes tive regulator of EZH2 expression, have been described in play in cell fate decisions (41). prostate cancer, thus providing a mechanism for EZH2 Mutations of other PRC2 components have not overexpression (32). Experimental support for the onco- been reported, although SUZ12 (also known as JJAZ1) genic action of EZH2 has been provided by induction of fuses to juxtaposed with another zinc finger 1 (JAZF1)in

www.aacrjournals.org Clin Cancer Res; 17(9) May 1, 2011 2615

Chase and Cross

endometrial stromal tumors (42). In addition, mutations ferential effects on gene reexpression patterns with different have been reported in a growing number of genes encoding combinatorial approaches with DZNep, DNA demethylat- functionally related epigenetic components. For example, ing agents, and HDAC inhibitors (54). In AML, combined inactivating mutations of ubiquitously transcribed tetratri- treatment with DZNep and the HDAC inhibitor panobino- copeptide repeat gene on X chromosome (UTX), an H3K27 stat induced a synergistic apoptotic effect upon primary demethylase, are seen in a wide range of malignancies and leukemia cells compared with normal cells (55). The com- may also be functionally equivalent to EZH2 overexpression plexity of the interactions between different epigenetic (43). Inactivating mutations of the PRC2 downstream sub- marks is highlighted by recent work showing downregula- strate DNMT3A are seen in acute myeloid leukemia (AML; tion of BMI1 and EZH2, by treatment with the HDAC ref. 44), and other PcG members such as ASXL1 (additional inhibitors valproic acid or sodium butyrate by mechanisms sex combs-like 1) are mutated in myeloid malignancies (45). that are currently unclear (56). The concept of "synthetic lethality" refers to the depen- Clinical-Translational Advances dency of a tumor on the presence of either 1 of 2 genes, but with resulting cell death if both are lost. Recently, a possible The therapeutic modulation of epigenetic marks has led "synthetic lethal" relationship between EZH2 and BRCA1 to improvements in treatment of some cancers, for exam- was described. BRCA1 plays a role in differentiation of ple, the use of DNA demethylating agents azacytidine and breast stem cells in addition to a well-documented role in decitabine for myelodysplastic syndrome (46, 47) and the DNA repair. In a mouse model of basal-type tumors (which HDAC inhibitor suberoylanilide hydroxamic acid (vorino- are generally poorly differentiated and do not express stat) for cutaneous T-cell lymphoma (48). In contrast to ERBB2, estrogen, or progesterone receptors and are, there- DNA demethylating agents and HDAC inhibitors, no thera- fore, without rational therapeutic targets), EZH2 expression pies that directly target histone methylation are clinically was found to be higher in BRCA1-deficient tumors com- available, despite the fact that there is experimental evi- pared with those that were wild-type. Remarkably, knock- dence for a potential therapeutic benefit for this approach. down of EZH2 by RNAi or by treatment with DZNep was Most experimental work on the inhibition of EZH2 activity 20 times more efficient at killing BRCA1-deficient cells has used the carbocyclic adenosine analog 3-deazanepla- (57). Further work has shown that EZH2 knockdown nocin (DZNep), a derivative of the naturally occurring can result in increased BRCA1 expression with a concomi- antibiotic neplanocin-A, in which ribose is replaced by a tant contribution to reduced proliferation (58). cyclopentyl ring (49). DZNep inhibits S-adenosylhomo- Although the development of histone demethylating cysteine hydrolase, a component of the methionine cycle, agents is an area of great interest, currently no compounds resulting in accumulation of the inhibitory S-adenosylho- are approved for treatment or in clinical trials. However, it mocysteine with a knock-on disruption of methylation of is clear that modulation of EZH2 levels and H3K27 methy- substrates by EZH2 (Fig. 1D). The effect of DZNep upon lation can be achieved by therapies primarily directed at histone methylation is, therefore, global rather than EZH2 DNA methylation or histone acetylation. Although there is specific (50). A comparison of DZNep action and specific an obvious rationale for inhibiting EZH2 function in knockdown of EZH2 by targeted RNAi has shown inter- malignancies in which this gene is overactive as a conse- esting differences; DZNep reduces levels of EZH2 protein quence of overexpression or Y641 mutation, the finding of but not the mRNA, whereas RNAi reduces both protein and inactivating mutations in myeloid neoplasms suggests that mRNA levels. Both strategies result in loss of H3K27 this approach will need to be employed with caution. methylation but differ somewhat in the pattern of genes Understanding how to effectively combine current treat- that are reexpressed (51). Inhibition of EZH2 by either ments with future histone demethylating agents will be a DZNep or RNAi leads to reduced proliferation in a subset major challenge in the coming years. of breast cancer cell lines (51) and reduced proliferation and invasiveness in prostate cancer cell lines (24, 51, 52). Disclosure of Potential Conflicts of Interest After initial work on DZNep as a single agent histone methylation inhibitor, in vitro experimental work pro- No potential conflicts of interest were disclosed. gressed to the use of combinatorial approaches to modify The costs of publication of this article were defrayed in part by the histone methylation, acetylation, and DNA methylation. In payment of page charges. This article must therefore be hereby marked breast cancer cell lines, DZNep treatment and HDAC advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. inhibition result in synergistic effects upon proliferation, apoptosis, differentiation, and cell cycle arrest (53). Chro- Received November 24, 2010; revised January 10, 2011; accepted January matin immunoprecipitation experiments have shown dif- 11, 2011; published OnlineFirst March 2, 2011.

References 1. Bernstein BE, Mikkelsen TS, Xie X, Kamal M, Huebert DJ, Cuff J, et al. 2. Azuara V, Perry P, Sauer S, Spivakov M, Jrgensen HF, John RM, et al. A bivalent chromatin structure marks key developmental genes in Chromatin signatures of pluripotent cell lines. Nat Cell Biol 2006; embryonic stem cells. Cell 2006;125:315–26. 8:532–8.

2616 Clin Cancer Res; 17(9) May 1, 2011 Clinical Cancer Research

Aberrations of EZH2 in Cancer

3. Oguro H, Yuan J, Ichikawa H, Ikawa T, Yamazaki S, Kawamoto H, 25. Kleer CG, Cao Q, Varambally S, Shen R, Ota I, Tomlins SA, et al. EZH2 et al. Poised lineage specification in multipotential hematopoietic is a marker of aggressive breast cancer and promotes neoplastic stem and progenitor cells by the polycomb protein Bmi1. Cell Stem transformation of breast epithelial cells. Proc Natl Acad Sci U S A Cell 2010;6:279–86. 2003;100:11606–11. 4. Sarma K, Margueron R, Ivanov A, Pirrotta V, Reinberg D. Ezh2 requires 26. Arisan S, Buyuktuncer ED, Palavan-Unsal N, Cas¸kurlu T, Cakir OO, PHF1 to efficiently catalyze H3 lysine 27 trimethylation in vivo. Mol Cell Ergenekon E. Increased expression of EZH2, a polycomb group Biol 2008;28:2718–31. protein, in bladder carcinoma. Urol Int 2005;75:252–7. 5. Kuzmichev A, Margueron R, Vaquero A, Preissner TS, Scher M, 27. Raman JD, Mongan NP, Tickoo SK, Boorjian SA, Scherr DS, Gudas Kirmizis A, et al. Composition and histone substrates of polycomb LJ. Increased expression of the polycomb group gene, EZH2, in repressive group complexes change during cellular differentiation. transitional cell carcinoma of the bladder. Clin Cancer Res 2005; Proc Natl Acad Sci U S A 2005;102:1859–64. 11:8570–6. 6. Peng JC, Valouev A, Swigut T, Zhang J, Zhao Y, Sidow A, et al. Jarid2/ 28. Weikert S, Christoph F, Kollermann€ J, Muller€ M, Schrader M, Miller K, Jumonji coordinates control of PRC2 enzymatic activity and target et al. Expression levels of the EZH2 polycomb transcriptional repres- gene occupancy in pluripotent cells. Cell 2009;139:1290–302. sor correlate with aggressiveness and invasive potential of bladder 7. Shen X, Kim W, Fujiwara Y, Simon MD, Liu Y, Mysliwiec MR, et al. carcinomas. Int J Mol Med 2005;16:349–53. Jumonji modulates polycomb activity and self-renewal versus differ- 29. Matsukawa Y, Semba S, Kato H, Ito A, Yanagihara K, Yokozaki H. entiation of stem cells. Cell 2009;139:1303–14. Expression of the enhancer of zeste homolog 2 is correlated with poor 8. Wang L, Brown JL, Cao R, Zhang Y, Kassis JA, Jones RS. Hierarchical prognosis in human gastric cancer. Cancer Sci 2006;97:484–91. recruitment of polycomb group silencing complexes. Mol Cell 30. Watanabe H, Soejima K, Yasuda H, Kawada I, Nakachi I, Yoda S, et al. 2004;14:637–46. Deregulation of histone lysine methyltransferases contributes to 9. Bracken AP, Dietrich N, Pasini D, Hansen KH, Helin K. Genome-wide oncogenic transformation of human bronchoepithelial cells. Cancer mapping of Polycomb target genes unravels their roles in cell fate Cell Int 2008;8:15. transitions. Genes Dev 2006;20:1123–36. 31. Sudo T, Utsunomiya T, Mimori K, Nagahara H, Ogawa K, Inoue H, 10. Jacobs JJ, Kieboom K, Marino S, DePinho RA, van Lohuizen M. The et al. Clinicopathological significance of EZH2 mRNA expression in oncogene and Polycomb-group gene bmi-1 regulates cell prolifera- patients with hepatocellular carcinoma. Br J Cancer 2005;92:1754–8. tion and senescence through the ink4a locus. Nature 1999;397:164–8. 32. Cao P, Deng Z, Wan M, Huang W, Cramer SD, Xu J, et al. MicroRNA-101 11. Lessard J, Schumacher A, Thorsteinsdottir U, van Lohuizen M, Mag- negatively regulates Ezh2 and its expression is modulated by androgen nuson T, Sauvageau G. Functional antagonism of the Polycomb- receptor and HIF-1alpha/HIF-1beta. Mol Cancer 2010;9:108. Group genes eed and Bmi1 in hemopoietic cell proliferation. Genes 33. Bracken AP, Pasini D, Capra M, Prosperini E, Colli E, Helin K. EZH2 is Dev 1999;13:2691–703. downstream of the pRB-E2F pathway, essential for proliferation and 12. Oguro H, Iwama A, Morita Y, Kamijo T, van Lohuizen M, Nakauchi H. amplified in cancer. EMBO J 2003;22:5323–35. Differential impact of Ink4a and Arf on hematopoietic stem cells and 34. Ohm JE, McGarvey KM, Yu X, Cheng L, Schuebel KE, Cope L, et al. A their bone marrow microenvironment in Bmi1-deficient mice. J Exp stem cell-like chromatin pattern may predispose tumor suppressor Med 2006;203:2247–53. genes to DNA hypermethylation and heritable silencing. Nat Genet 13. Majewski IJ, Ritchie ME, Phipson B, Corbin J, Pakusch M, Ebert A, 2007;39:237–42. et al. Opposing roles of polycomb repressive complexes in hemato- 35. Schlesinger Y, Straussman R, Keshet I, Farkash S, Hecht M, Zimmer- poietic stem and progenitor cells. Blood 2010;116:731–9. man J, et al. Polycomb-mediated methylation on Lys27 of histone H3 14. Rinn JL, Kertesz M, Wang JK, Squazzo SL, Xu X, Brugmann SA, et al. pre-marks genes for de novo methylation in cancer. Nat Genet Functional demarcation of active and silent chromatin domains in 2007;39:232–6. human HOX loci by noncoding RNAs. Cell 2007;129:1311–23. 36. Widschwendter M, Fiegl H, Egle D, Mueller-Holzner E, Spizzo G, 15. Tsai MC, Manor O, Wan Y, Mosammaparast N, Wang JK, Lan F, et al. Marth C, et al. Epigenetic stem cell signature in cancer. Nat Genet Long noncoding RNA as modular scaffold of histone modification 2007;39:157–8. complexes. Science 2010;329:689–93. 37. Morin RD, Johnson NA, Severson TM, Mungall AJ, An J, Goya R, et al. 16. Van Dessel N, Beke L, Gornemann J, Minnebo N, Beullens M, Tanuma Somatic mutations altering EZH2 (Tyr641) in follicular and diffuse large N, et al. The phosphatase interactor NIPP1 regulates the occupancy B-cell lymphomas of germinal-center origin. Nat Genet 2010;42:181– of the histone methyltransferase EZH2 at Polycomb targets. Nucleic 5. Acids Res 2010;38:7500–12. 38. Sneeringer CJ, Scott MP, Kuntz KW, Knutson SK, Pollock RM, Richon 17. Mohd-Sarip A, Venturini F, Chalkley GE, Verrijzer CP. Pleiohomeotic VM, et al. Coordinated activities of wild-type plus mutant EZH2 drive can link polycomb to DNA and mediate transcriptional repression. Mol tumor-associated hypertrimethylation of lysine 27 on histone H3 Cell Biol 2002;22:7473–83. (H3K27) in human B-cell lymphomas. Proc Natl Acad Sci U S A 18. Landeira D, Fisher AG. Inactive yet indispensable: the tale of Jarid2. 2010;107:20980–5. Trends Cell Biol 2010; 21:74–80. 39. Ernst T, Chase AJ, Score J, Hidalgo-Curtis CE, Bryant C, Jones AV, 19. Vire E, Brenner C, Deplus R, Blanchon L, Fraga M, Didelot C, et al. The et al. Inactivating mutations of the histone methyltransferase gene Polycomb group protein EZH2 directly controls DNA methylation. EZH2 in myeloid disorders. Nat Genet 2010;42:722–6. Nature 2006;439:871–4. 40. Nikoloski G, Langemeijer SM, Kuiper RP, Knops R, Massop M, 20. Rush M, Appanah R, Lee S, Lam LL, Goyal P, Lorincz MC. Targeting of Tonnissen€ ER, et al. Somatic mutations of the histone methyltransfer- EZH2 to a defined genomic site is sufficient for recruitment of Dnmt3a ase gene EZH2 in myelodysplastic syndromes. Nat Genet 2010; but not de novo DNA methylation. Epigenetics 2009;4:404–14. 42:665–7. 21. McGarvey KM, Greene E, Fahrner JA, Jenuwein T, Baylin SB. DNA 41. Sauvageau M, Sauvageau G. Polycomb group proteins: multi-faceted methylation and complete transcriptional silencing of cancer genes regulators of somatic stem cells and cancer. Cell Stem Cell 2010; persist after depletion of EZH2. Cancer Res 2007;67:5097–102. 7:299–313. 22. Van Der Vlag J, Otte AP. Transcriptional repression mediated by the 42. Koontz JI, Soreng AL, Nucci M, Kuo FC, Pauwels P, Van Den Berghe human polycomb-group protein EED involves histone deacetylation. H, et al. Frequent fusion of the JAZF1 and JJAZ1 genes in endometrial Nat Genet 1999;23:474–8. stromal tumors. Proc Natl Acad Sci U S A 2001;98:6348–53. 23. Garrick D, De Gobbi M, Samara V, Rugless M, Holland M, Ayyub H, 43. van Haaften G, Dalgliesh GL, Davies H, Chen L, Bignell G, Greenman et al. The role of the polycomb complex in silencing alpha-globin gene C, et al. Somatic mutations of the histone H3K27 demethylase gene expression in nonerythroid cells. Blood 2008;112:3889–99. UTX in human cancer. Nat Genet 2009;41:521–3. 24. Varambally S, Dhanasekaran SM, Zhou M, Barrette TR, Kumar-Sinha 44. Ley TJ, Ding L, Walter MJ, McLellan MD, Lamprecht T, Larson DE, C, Sanda MG, et al. The polycomb group protein EZH2 is involved in et al. DNMT3A mutations in acute myeloid leukemia. N Engl J Med progression of prostate cancer. Nature 2002;419:624–9. 2010;363:2424–33.

www.aacrjournals.org Clin Cancer Res; 17(9) May 1, 2011 2617

Chase and Cross

45. Carbuccia N, Murati A, Trouplin V, Brecqueville M, Adelaïde J, Rey J, repression selectively induces apoptosis in cancer cells. Genes Dev et al. Mutations of ASXL1 gene in myeloproliferative neoplasms. 2007;21:1050–63. Leukemia 2009;23:2183–6. 52. Bryant RJ, Cross NA, Eaton CL, Hamdy FC, Cunliffe VT. EZH2 46. Fenaux P, Mufti GJ, Hellstrom-Lindberg E, Santini V, Finelli C, Giagou- promotes proliferation and invasiveness of prostate cancer cells. nidis A, et al. International Vidaza High-Risk MDS Survival Study Group. Prostate 2007;67:547–56. Efficacy of azacitidine compared with that of conventional care regimens 53. Hayden A, Johnson PW, Packham G, Crabb SJ. S-adenosylhomo- in the treatment of higher-risk myelodysplastic syndromes: a rando- cysteine hydrolase inhibition by 3-deazaneplanocin A analogues mised, open-label, phase III study. Lancet Oncol 2009;10:223– induces anti-cancer effects in breast cancer cell lines and synergy 32. with both histone deacetylase and HER2 inhibition. Breast Cancer Res 47. Fenaux P, Mufti GJ, Hellstrom-Lindberg€ E, Santini V, Gattermann N, Treat 2010. Epub 2010 Jun 17. Germing U, et al. Azacitidine prolongs overall survival compared 54. Sun F, Chan E, Wu Z, Yang X, Marquez VE, Yu Q. Combinatorial with conventional care regimens in elderly patients with low bone pharmacologic approaches target EZH2-mediated gene repression in marrow blast count acute myeloid leukemia. J Clin Oncol 2010;28: breast cancer cells. Mol Cancer Ther 2009;8:3191–202. 562–9. 55. Fiskus W, Wang Y, Sreekumar A, Buckley KM, Shi H, Jillella A, et al. 48. Olsen EA, Kim YH, Kuzel TM, Pacheco TR, Foss FM, Parker S, et al. Combined epigenetic therapy with the histone methyltransferase Phase IIb multicenter trial of vorinostat in patients with persistent, EZH2 inhibitor 3-deazaneplanocin A and the histone deacetylase progressive, or treatment refractory cutaneous T-cell lymphoma. J inhibitor panobinostat against human AML cells. Blood 2009;114: Clin Oncol 2007;25:3109–15. 2733–43. 49. Glazer RI, Hartman KD, Knode MC, Richard MM, Chiang PK, Tseng 56. Bommi PV, Dimri M, Sahasrabuddhe AA, Khandekar JD, Dimri GP. CK, et al. 3-Deazaneplanocin: a new and potent inhibitor of S-ade- The polycomb group protein BMI1 is a transcriptional target of HDAC nosylhomocysteine hydrolase and its effects on human promyelocytic inhibitors. Cell Cycle 2010;9. Epub 2010 Jul 21. leukemia cell line HL-60. Biochem Biophys Res Commun 1986; 57. Puppe J, Drost R, Liu X, Joosse SA, Evers B, Cornelissen-Steijger P, 135:688–94. et al. BRCA1-deficient mammary tumor cells are dependent on EZH2 50. Miranda TB, Cortez CC, Yoo CB, Liang G, Abe M, Kelly TK, et al. expression and sensitive to Polycomb Repressive Complex 2-inhibi- DZNep is a global histone methylation inhibitor that reactivates tor 3-deazaneplanocin A. Breast Cancer Res 2009;11:R63. developmental genes not silenced by DNA methylation. Mol Cancer 58. Gonzalez ME, Li X, Toy K, DuPrie M, Ventura AC, Banerjee M, et al. Ther 2009;8:1579–88. Downregulation of EZH2 decreases growth of estrogen receptor- 51. Tan J, Yang X, Zhuang L, Jiang X, Chen W, Lee PL, et al. Pharma- negative invasive breast carcinoma and requires BRCA1. Oncogene cologic disruption of Polycomb-repressive complex 2-mediated gene 2009;28:843–53.

2618 Clin Cancer Res; 17(9) May 1, 2011 Clinical Cancer Research

Aberrations of EZH2 in Cancer

Andrew Chase and Nicholas C.P. Cross

Clin Cancer Res 2011;17:2613-2618. Published OnlineFirst March 2, 2011.

Updated version Access the most recent version of this article at: doi:10.1158/1078-0432.CCR-10-2156

Cited articles This article cites 56 articles, 21 of which you can access for free at: http://clincancerres.aacrjournals.org/content/17/9/2613.full#ref-list-1

Citing articles This article has been cited by 52 HighWire-hosted articles. Access the articles at: http://clincancerres.aacrjournals.org/content/17/9/2613.full#related-urls

E-mail alerts Sign up to receive free email-alerts related to this article or journal.

Reprints and To order reprints of this article or to subscribe to the journal, contact the AACR Publications Subscriptions Department at [email protected].

Permissions To request permission to re-use all or part of this article, use this link http://clincancerres.aacrjournals.org/content/17/9/2613. Click on "Request Permissions" which will take you to the Copyright Clearance Center's (CCC) Rightslink site.