Structure enabled design of BaZ2-ICR, a chemical probe targeting the bromodomains of BaZ2a and BaZ2B

Article abstract of DOI:10.1021/jm501963e

The bromodomain containing proteins BaZ2a/B play essential roles in chromatin remodeling and regulation of noncoding RNas. We present the structure based discovery of a potent, selective, and cell active inhibitor 13 (BaZ2-ICR) of the BaZ2a/B bromodomains through rapid optimization of a weakly potent starting point. a key feature of the presented inhibitors is an intramolecular aromatic stacking interaction that efficiently occupies the shallow bromodomain pockets. 13 represents an excellent chemical probe for functional studies of the BaZ2 bromodomains in vitro and in vivo.

Full text of DOI:10.1021/jm501963e

Brief Article
pubs.acs.org/jmc
Structure Enabled Design of BAZ2-ICR, A Chemical Probe Targeting
the Bromodomains of BAZ2A and BAZ2B
Ludovic Drouin,† Sally McGrath,† Lewis R. Vidler,† Apirat Chaikuad,‡ Octovia Monteiro,‡,§
Cynthia Tallant,‡,§ Martin Philpott,‡,§ Catherine Rogers,‡,§ Oleg Fedorov,‡,§ Manjuan Liu,†
Wasim Akhtar,† Angela Hayes,† Florence Raynaud,† Susanne Muller,‡,§ Stefan Knapp,*,‡,§
̈
and Swen Hoelder*,†
†The Institute of Cancer Research, Division of Cancer Therapeutics, Cancer Research UK Cancer Therapeutics Unit, 15 Cotswold
Road, Sutton, London SM2 5NG, U.K.
‡The Structural Genomic Consortium, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Headington,
Oxford OX3 7DQ, U.K.
§Target Discovery Institute, University of Oxford, NDM Research Building, Roosevelt Drive, Headington, Oxford OX3 7FZ, U.K.
S
* Supporting Information
ABSTRACT: The bromodomain containing proteins
BAZ2A/B play essential roles in chromatin remodeling and
regulation of noncoding RNAs. We present the structure based
discovery of a potent, selective, and cell active inhibitor 13
(BAZ2-ICR) of the BAZ2A/B bromodomains through rapid
optimization of a weakly potent starting point. A key feature of
the presented inhibitors is an intramolecular aromatic stacking
interaction that efficiently occupies the shallow bromodomain
pockets. 13 represents an excellent chemical probe for
functional studies of the BAZ2 bromodomains in vitro and
in vivo.
logue (SNF2h) the nucleolar remodeling complex (NoRC), a
member of the imitation switch chromatin remodeling
complexes (ISWI).6 NoRC has been shown to regulate
expression of noncoding RNAs and also establishes a repressive
heterochromatic structure at centromeres and telomeres.7
Interestingly, mutations in the BAZ2A bromodomain that
abolish histone binding impair association of NoRC with
chromatin and transcriptional repression.8 In addition, single
nucleotide polymorphisms (SNPs) in the BAZ2B gene locus
have been identified as being associated with sudden cardiac
death9 and high expression levels of BAZ2B have found to be
associated with poor outcome of pediatric B cell acute
lymphoblastic leukemia (B-ALL), raising the potential that
BAZ2B inhibitors may have therapeutic potential for this
cancer. Furthermore, a recent publication reports that BAZ2A
is involved in maintaining prostate cancer cell growth and
establishes a correlation between BAZ2A expression and
recurrence in prostate cancer.10
INTRODUCTION
■
Bromodomains are acetyl-lysine specific epigenetic reader
domains and an emerging new target class for the design of
protein interaction inhibitors that selectively modulate gene
transcription.1,2 However, the discovery of potent and selective
inhibitors has been mainly focused on the bromo and extra-
terminal (BET) subfamily of bromodomains (BRD2, BRD3,
BRD4, BRDT) for which first inhibitors have reached clinical
testing1 and no potent and selective inhibitors are known for
the large majority of bromodomains.3 This paucity of selective
chemical probes represents a barrier for the identification and
validation of additional bromodomains as therapeutic targets.
Chemical probes have several advantages for target identi-
fication and validation over commonly used genetic techniques
like RNAi experiments and dominant negative mutants.4 This is
particularly relevant for bromodomains because these proteins
often function as scaffolding proteins in larger multidomain
proteins, suggesting that depletion of the entire protein, e.g., by
RNAi does not reflect inhibition of a specific interaction by a
small molecule drug.
Interestingly, BAZ2A/B show low predicted druggability11
due to an open binding site that lacks the deep and enclosed
pocket characteristic for the BET subfamily bromodomains. No
potent and selective inhibitors have been published, although a
number of weak and nonselective fragments have been reported
Two homologous bromodomains for which no potent and
selective inhibitors have been published so far are BAZ2A and
BAZ2B. Bromodomain adjacent to zinc finger domain (BAZ)
represents a family of ubiquitously expressed proteins (BAZ1A,
BAZ1B, BAZ2A, and BAZ2B) with a similar domain structure.5
BAZ2A forms with ATPase sucrose nonfermenting-2 homo-
Received: December 19, 2014
Published: February 26, 2015
© 2015 American Chemical Society
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Journal of Medicinal Chemistry
Brief Article
recently.12 To identify chemical starting points for these
challenging targets, we screened a series of putative BRD
inhibitors obtained in the course of a virtual screening
campaign.13 Consistent with the difficult nature of this target,
we identified a single compound (1, Figure 1) as a weak
Furthermore, the nitrile function and one of the triazole ring
nitrogen atoms engage in hydrogen bonds with backbone
atoms Leu1891 and Asn1894 (Figure 1b). The internal π-
stacking arrangement of these two aromatic groups thus
represented an excellent shape and hydrogen bonding
complementary to the open BAZ2B pocket, maximizing polar
and hydrophobic interactions, and was thus likely critical for the
observed potency and selectivity.
Our aim starting from 1 was to identify a potent and selective
inhibitor of BAZ2A/B that is active in the cellular context in the
low/submicromolar range. We therefore aimed to improve the
in vitro activity 100−200-fold while maintaining high selectivity
for BAZ2A/B.
On the basis of the crystal structure, we hypothesized that a
large gain in potency can be achieved by replacing the phenyl
ring of 1 that occupied the KAc pocket by a moiety that mimics
the hydrogen bond network of KAc. We thus designed a small
set of compounds in which the phenyl group of 1 was replaced
by known KAc mimetics1 or other heterocycles that can engage
in hydrogen bonds (Table 1) and set out to develop a concise
and efficient synthetic route to these compounds.
Figure 1. Interaction between BAZ2B and 1. (a) Chemical structure of
1. (b) 1.8 Å cocrystal structures of 1 bound to BAZ2B (PDB: 4XUA).
Main interacting residues are shown in ball and stick representation
and are labeled. Conserved water molecules (w) in the KAc binding
site are shown as pink spheres. The inset shows the |2FO| − |FC|
omitted map for 1, contoured at 1σ.
Careful optimization led to the three-step route depicted in
Scheme 1. An initial three component Van Leusen imidazole
formation enabled us to access imidazole intermediates in 10−
inhibitor of BAZ2A (IC50 = 51 μM) and BAZ2B (IC50 = 26
μM). Here we describe the optimization of 1, ultimately
resulting in the discovery of 13 (BAZ2-ICR), a potent and
selective chemical probe of the BAZ2 bromodomains.
Table 1. Structure−Activity Relationship of Triazole
a
Substituted Compounds
RESULTS AND DISCUSSION
■
To shed light on the binding mode and derive design
hypotheses for the optimization of 1, we solved the crystal
structure of 1 bound to BAZ2B to 1.8 Å resolution. This
cocrystal structure revealed a number of interesting features.
Bromodomains bind to acetylated lysines (KAc) through a
conserved pocket (KAc pocket). All bromodomain inhibitors
known to date bind to this pocket through a KAc mimetic
group, often a heterocyclic ring that engages in hydrogen bonds
with a conserved asparagine residue and a conserved water
molecule.14 We initially hypothesized that the methyl-triazolo
group of 1 (a putative KAc mimetic) acts as the KAc mimetic.
Surprisingly, the cocrystal structure revealed the hydrophobic
phenyl ring of 1 occupied the KAc binding pocket despite the
presence of conserved water molecules and the asparagine
residue (N1944, numbering according to isoform 4 (gi|
7304923)), both of which typically act as hydrogen bond
donors (Figure 1).
Another surprising feature of the structure of 1 bound to
BAZ2B was an intramolecular, face-to-face π-stacking inter-
action formed by the nitrile substituted phenyl ring and the
triazole ring of 1. The distance between these two rings of ∼3 Å
is in the typical range for face-to-face π-stackings. The
energetics of a π-stacked conformation is typically driven by
two factors: solvent exclusion and electronic complementarity
of the two aromatic rings to minimize the repulsion of the π-
clouds.15 We performed a field analysis using the XED force
field from Cresset16 to investigate the electronic characters of
the two aromatic rings which form the stacking interaction.
This analysis showed that the triazole ring was electron rich on
the face of the ring and the nitrile substituted phenyl ring
electron poor (see Supporting Information (SI)). These
complementary properties thus likely contributed to the
formation of the stacking conformation.
a
IC50 values are given in μM.
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Scheme 1. Three-Step Synthesis of Imidazole Small
a
Molecule Ligand
a
Reagents and conditions. Van Leusen Reaction: Aldehyde (1.0
equiv), amine (1.5 equiv), glacial acetic acid (2.0 equiv), ethanol,
reflux, 4 h; then evaporation, K2CO3 (2.0 equiv), TosMIC (1.5 equiv),
DMF, 95 °C. Bromination: DBDMH (0.5 equiv), DMF, 0−25 °C, 20
h. C−C Bond Formation: Pd(PPh3)4 (0.08 equiv), Stille reagent (2.0
equiv), dioxane, 150 °C under microwaves, 1.5 h.
Figure 2. Crystal structure of the BAZ2B bromodomain in complex
with 7. (a) Detailed interaction between 7 (yellow stick) and BAZ2B
in the crystal structure with |2FO| − |FC| omitted map contoured at 1 σ
for 7 shown in the inset (PDB: 4XUB). Hydrogen bonds are shown as
dashed orange lines, while the dashed magenta lines indicated the
smallest distances between the triazole ring to the π-stacking partner
benzonitrile and to L1897. (b) Superimposition of the BAZ2B−1, −7,
and −KAc complexes. Conserved water molecules bound within the
KAc binding site are shown in pink spheres.
66% yield. Regioselective bromination of imidazole (35−67%
yield) and microwave assisted Stille (45−54% yield) or Suzuki
(6−47% yield) coupling gave the final compounds 1, 2, 3, 4,
and 7. For the synthesis of 5, we used a two-step process from
the brominated imidazole involving a palladium catalyzed
formation of the corresponding alkyne followed by a 1,3-dipolar
cycloaddition with chloro acetaldoxime (30% yield over two
steps).
substituted isoxazole (a well-known BET bromodomain
inhibitor warhead), was completely inactive. The oxygen
atom cannot engage in hydrogen bond to the conserved
asparagine as it does in complexes with other bromodomains.3
The increased desolvation penalty caused by the additional
acceptor is thus not compensated through a hydrogen bond.
Furthermore, we speculated that differences in the conforma-
tional preferences of the pyrazole and the isoxazole ring
contributed to the lack of activity. We performed an analysis of
the preferred torsion angles between the imidazole on one hand
and the pyrazole ring of 7 and the isoxazole ring of 5 on the
other hand, while the rest of the molecules was kept in the
bioactive conformation. In the case of 7, the torsion angle with
the lowest predicted energy is indeed similar to the torsion
angle observed in the crystal structure. In strong contrast, our
analysis of 5 predicted a lowest energy torsion angle that is not
compatible with binding because the isoxazole methyl group
pointed in the opposite direction compared to the pyrazole
methyl substituent of 7 (see SI). This conformation is likely
preferred because it allowed a more coplanar orientation of the
isoxazole with the imidazole (10° deviation from the coplanar
orientation compared to 30° for the conformation compatible
with binding). Penalties due to desolvation and higher energy
conformation thus collectively cause the complete loss of
activity for 5.
We initially tested all compounds using AlphaScreen assays.17
The pyridine 2 showed a significant improvement in activity,
suggesting that the pyridine nitrogen indeed engaged in a
hydrogen bond with one of the conserved water molecules at
the base of the pocket. Interestingly, the meta pyridine 3 was
inactive, very likely because the pyridine nitrogen is situated in
a less favorable position to interact with the water molecules
compared to 2. The thiazole 4 demonstrated that 5-membered
KAc mimetics can also exhibit improved activity. Finally, we
prepared and tested 5 and 7, both featuring 5-membered KAc
mimetics that we designed to engage in a hydrogen bond and
mimic the terminal methyl group of KAc through a methyl
substituent. Interestingly, these gave very different results.
Isoxazole 5 did not inhibit BAZ2A and B to a significant degree,
which was surprising given that the methyl isoxazole is a well-
known KAc mimetic (vide infra). The pyrazole derivative 7, on
the other hand, was the most potent inhibitor out of this initial
set with IC50 values of 0.6 and 1.07 μM for BAZ2A and BAZ2B,
respectively. We had thus achieved an almost 100-fold increase
in potency for BAZ2A and a 25-fold increase for BAZ2B
without increasing molecular weight, thus also improving the
ligand efficiency (Table 1).
Having achieved a large leap in activity, we decided to
investigate whether 7 adopts the stacked, bioactive conforma-
tion evident from crystal structure upon binding to the target or
whether this bioactive conformation is already populated to a
significant degree in solution prior to binding to BAZ2A/B. We
hypothesized that if the former was the case, binding to BAZ2
will result in a free energy penalty caused by adopting the
bioactive conformation. In this scenario, stabilizing this
conformation might reduce the penalty and result in an
increase in activity.
To support our design hypothesis, we subsequently
determined the crystal structure (2.0 Å) of BAZ2B in complex
with 7 to confirm the acetyl-lysine mimetic binding mode of the
introduced methyl pyrazole (Figure 2). The pyrazole acted
indeed as an acetyl-lysine mimetic moiety, forming a hydrogen
bond with a conserved water molecule that also interacts with
the conserved Y1901. Superimposition of 7- and KAc-
complexed structures12 confirmed that the methyl substituent
of pyrazole occupied the position typically filled by the terminal
methyl group of KAc. In all other aspects, the cocrystal
structure of 7 resembled the structure of 1 bound to BAZ2B,
confirming that the increased activity in 7 was indeed due to
the optimized KAc mimetic.18 To our knowledge, this
represented the first example of a pyrazole moiety as the KAc
mimetic in a bromodomain inhibitor.
1
To investigate the solution conformation of 7, we used H
NMR spectroscopy.
We hypothesized that in the stacked conformation the signals
of protons H-2′/H-6′ (Figure 3, labeled in red) will shift
significantly upfield due to the anisotropic effect arising from
the ring current of triazole ring compared to 8, which does not
feature the triazole ring.19 However, the H-2′/H2-6′ protons of
7 and 8 showed near identical chemical shifts in D2O.
The insights from the crystal structure of 7 also provided a
potential explanation why 5, which featured a methyl
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Table 2. Structure−Activity Relationship of N-Methyl
a
Pyrazole Substituted Compounds
1
Figure 3. Conformations of 6, 7, 8, and 9 were investigated by H
NMR in D2O at 295 K. The red asterisks mark the signals from
protons ortho to the nitrile group.
1
Furthermore, the H−1H NOESY spectrum of 7 did not show
a correlation between these protons and the protons on the
methyl group of the triazole ring (see SI). Both results
suggested that 7 did not adopt the π-stacking conformation to a
significant degree in solution.
Interestingly, when we performed a similar set of experi-
ments for intermediate 6 (Figure 3), a clear shift of the protons
(0.12 ppm) compared to 9 as well as a NOESY correlation
were apparent, strongly indicating that contrary to 7 the less
substituted 6 does adopt a conformation in solution in which
the two aryl rings are in close proximity. While 6 did not show
significant binding (Table 1), this validated the NMR method,
thus further increasing our confidence that 7 did not adopt the
bioactive conformation to a large degree in solution. The
different behavior with regard to the conformation in solution
between 6 and 7 is likely caused by the additional heteroaryl
substituent of 7 that makes adoption of this conformation less
favorable.
On the basis of the crystal structure of 7 and the observation
that 7 did not adopt the bioactive conformation in solution, we
next designed a set of follow up compounds to further increase
the potency by optimizing the interactions with the protein and
stabilizing the bioactive, stacked conformation (Table 2).
Compounds 10, 11, and 12 feature electron withdrawing
fluorine or nitro substituents at the phenyl ring to increase the
electron withdrawing character of the phenyl ring and
strengthen the electronic component of the stacking
interaction. Our modeling experiments suggested that the
nitro group of 12 was well placed to engage in the same
hydrogen bonding interaction with the backbone donor of
Leu1891 as the nitrile group in 7.
a
IC50 values are given in μM.
this ring and thus the stability of the stacked conformation.
This led us to 13.
To investigate the importance of these groups, along with
10−13, we prepared 8 in which the entire triazole group is
removed. The screening results for this second set of
compounds are summarized in Table 2.
The complete loss of activity of 8, in which one-half of the
internal π-stacking has been removed, reinforces the
importance of this element for potent binding. As can be
further seen from Table 2, addition of a fluorine atom at both
positions of the phenyl ring was largely tolerated for BAZ2A
and BAZ2B but did not lead to a significant increase in activity.
The same held true for the nitro compound 12 that showed
comparable activity to 7.
Gratifyingly, replacement of the triazole with the pyrazole led
to a 5-fold increase in activity. Compound 13 inhibits BAZ2A
and BAZ2B with IC50s of 130 and 180 nM, respectively, thus
reaching our targeted potency. Compared to our starting point
1, 13 possesses a 200-fold increase in activity.
Furthermore, inspection of the crystal structure revealed that
N2 of the triazole ring was situated in a hydrophobic
environment formed by the side chains of Leu1897, Val1893,
and Val1898 and did not engage in a hydrogen bond. We
hypothesized that removing this nitrogen atom reduces the
desolvation penalty, increases the hydrophobic interactions
with the protein, and increases the electron rich character of
We performed the NMR experiments described above with
13. However, as for 7, the absence of a chemical shift and a
correlation of the protons in question in the H−1H NOESY
1
spectrum strongly indicated that 13 did not adopt the bioactive
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conformation to significant degree in solution. On the basis of
this observation, we believed that the increased potency was
indeed caused by improved hydrophobic interactions and
decreased desolvation penalty upon binding.
Next, we investigated the binding of 13 to BAZ2A/B by
isothermal titration calorimetry (ITC).
In very good agreement with the IC50s, the compound
showed Kds of 109 and 170 nM to BAZ2A and BAZ2B,
respectively (Figure 4). Interestingly, the binding was driven by
In agreement with the potent binding shown in our
biochemical assays as well as ITC, 13 showed significant
thermal shifts of 5.2 and 3.8 °C for BAZ2A and BAZ2B
respectively. Gratifyingly, 13 did not show significant thermal
shifts against all other bromodomains, except for Cat Eye
syndrome chromosome region, candidate 2 (CECR2), where
we observed a smaller but significant shift (ΔTm: 2.0 °C). We
determined the Kd of 13 to CERC2 by ITC to be 1.55 μM,
therefore resulting in a 15-fold selectivity when compared to
BAZ2A and a 10-fold window to BAZ2B.
To ensure that our probe showed a sufficient window to the
BET bromodomains, we tested 13 in a BRD4 AlphaScreen
assay, where it did not show significant inhibition up to 50 μM
translating in greater than 100-fold window. Furthermore, we
confirmed the selectivity against BRD4 in a cellular assay (vide
infra). Molecule 13 thus overall shows a very high degree of
selectivity within the bromodomain family.
Furthermore, a receptor screening performed at CEREP
against 55 possible off-targets returned a very clean profile (see
SI).
Figure 4. ITC data of the interaction of 13 with BAZ2A and BAZ2B.
Raw BAZ2A binding heats are shown in the left panel as well as
normalized integrated binding enthalpies for each injection in the right
panel. Nonlinear least-squares fits are shown as red solid lines.
To investigate whether 13 can displace BAZ2 bromodomains
from chromatin in living cells, we performed a fluorescence
recovery after photobleaching (FRAP) assay utilizing GFP-
tagged BAZ2A full length protein transfected into human
osteosarcoma cells (U2OS). As a control we used a mutant
(N1873F) that does not bind KAc containing peptides and
therefore mirrors the behavior of inhibitor bound BAZ2A. In
addition, we used the histone deacetylase (HDAC) inhibitor
SAHA to increase overall levels of histone acetylation, resulting
in a sufficient window measuring differences in recovery time
and demonstrating the acetylation dependence of the FRAP
experiments (Figure 6). Importantly, 1 μM 13 reduced the
recovery time of the wild-type (wt) construct to a level similar
to the dominant negative mutant, confirming that 13 inhibits
BAZ2A in cells.
large enthalpic contributions (ΔH = 17 kcal/mol for BAZ2A
and 9 kcal/mol for BAZ2B) and a loss of entropy, which is
consistent with a loss of conformational freedom of 13 due to
adoption of the bioactive conformation upon binding.
Having achieved our targeted potency, we next assessed the
selectivity of 13 by screening the compound against 47
bromodomains using thermal shift (Figure 5).20 The data are
visualized in Figure 5, and numerical values as well as available
control compounds are compiled in the SI.
Figure 6. Fluorescence recovery after photobleaching (FRAP) assay
data. Shown are recovery half times of wild-type and SAHA treated
cells as well as the bromodomain inactivating mutant (N1873F) and
13 treated wild-type cells. *P < 0.05, significant difference from wt
treated with SAHA.
To confirm selectivity in the cellular setting, we performed a
similar FRAP assay for BRD4 where 13 did not show any
significant activity (see SI).
Ideally, chemical probes can be used in vitro as well as in
vivo. To investigate whether 13 is suitable for in vivo
experiments, we assessed its physicochemical and mouse
pharmacokinetic properties. Compound 13 showed very high
solubility (25 mM in D2O), a measured log D of 1.05, high
stability in mouse microsomes, and permeation in the CaCo-2
Figure 5. Selectivity of 13. The inhibitor was screened at 10 μM
concentration against 47 bromodomains using temperature shift assay.
The screened targets are labeled on the phylogenetic tree, whereas
targets that have not been screened are shown in gray. Temperature
shifts are represented as spheres as indicated in the figure.
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model (see SI) and thus a suitable profile for oral and
intravenous gavage. We therefore performed a full mouse
pharmacokinetic experiment. In agreement with the in vitro
data, 13 showed 70% bioavailability and moderate clearance
(∼50% of mouse liver blood flow) and volume of distribution
(see SI). This set of data therefore suggested that 13 is suitable
for modulating BAZ2A and BAZ2B in vivo.
funding from Cancer Research UK (grant no. C309/A11566).
The SGC is a registered charity (no. 1097737) that receives
funds from AbbVie, Bayer Pharma AG, Boehringer Ingelheim,
the Canada Foundation for Innovation, Genome Canada,
GlaxoSmithKline, Janssen, Lilly Canada, the Novartis Research
Foundation, the Ontario Ministry of Economic Development
and Innovation, Pfizer, Takeda, and the Wellcome Trust
(092809/Z/10/Z).
CONCLUSIONS
■
REFERENCES
We describe the discovery of a potent and selective chemical
probe to target BAZ2A and BAZ2B bromodomains starting
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improvement in potency in just two cycles of design and
synthesis, underscoring the power of structure based design.
Moreover, our work highlights the utility of intramolecular π-
stacking to target challenging binding sites. In strong contrast
to many other bromodomains, e.g., the BET subfamily, BAZ2A
and B, show a low degree of druggability due to an open
binding pocket that lacks the high degree of enclosure observed
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Because of its excellent in vitro and in vivo profile, 13
(BAZ2-ICR) satisfies the criteria for a dual BAZ2A and BAZ2B
chemical probe. The compound is freely available to the
scientific community via http://www.thesgc.org/chemical-
probe/BAZ2-ICR. Experiments to investigate biological role
of BAZ2A and B are underway and will be published in due
course.
ASSOCIATED CONTENT
* Supporting Information
■
S
Experimental and characterization details for all new com-
pounds, computational data, ITC data, assays data, crystallo-
graphic data, pharmacokinetic data, and NMR spectra. This
material is available free of charge via the Internet at http://
pubs.acs.org.
AUTHOR INFORMATION
Corresponding Authors
*For S.H.: phone, +44 2087224353; E-mail, swen.hoelder@icr.
ac.uk.
■
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̈
Schapira, M.; Kuner, R.; Sultmann, H.; Provenzano, M.; ICGC Project
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on Early Onset Prostate Cancer, Yaspo, M.-L.; Brors, B.; Korbel, J.;
Schlomm, T.; Sauter, G.; Eils, R.; Plass, C.; Santoro, R. BAZ2A (TIP5)
is Involved in Epigenetic Alterations in Prostate Cancer and its
Overexpression Predicts Disease Recurrence. Nature Genet. 2014,
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*For S.K. phone, +44 1865612933; E-mail, stefan.knapp@sgc.
ox.ac.uk.
Notes
The authors declare no competing financial interest.
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ACKNOWLEDGMENTS
■
Lewis Vidler was funded by Cancer Research UK (grant no.
C309/A11369), Sally McGrath was funded by Wellcome Trust
(grant no. 090171/Z/09/Z), Wasim Akhtar was funded by
EPSRC DTG (grant no. EP/J500240/1). We acknowledge
NHS funding to the NIHR Biomedical Research Centre and
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