Targeting IRAK4 for Degradation with PROTACs

Article abstract of DOI:10.1021/acsmedchemlett.9b00219

Interleukin-1 Receptor-Associated Kinase 4 (IRAK4) is a key mediator of innate immunity. IRAK4 overactivation is linked with several autoimmune diseases. To date, many IRAK4 inhibitors have been developed to block the protein's kinase activity with the most advanced reaching Phase II clinical trials. Nevertheless, several reports suggest kinase activity is not disease-relevant in certain cell types, so removing scaffolding signaling in addition to IRAK4 kinase activity may offer a better therapeutic outcome. Herein, we describe the design and synthesis of an IRAK4 Proteolysis Targeted Chimera (PROTAC). We show that IRAK4 degradation induced by compound 9 leads to the inhibition of multiple cytokines in PBMCs. However, in IL-1β stimulated human dermal fibroblasts, inhibition of IL-6 and TNF-α release was not observed despite IRAK4 degradation. Nonetheless, the possibility of targeting both IRAK4 kinase and scaffolding function could potentially lead to new therapeutic opportunities to treat autoimmune, inflammatory, and oncological diseases.

Full text of DOI:10.1021/acsmedchemlett.9b00219

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Letter
Targeting IRAK4 for Degradation with PROTACs
Joao Nunes, Grant Andrew McGonagle, Jessica Eden, Girieshanie Kiritharan, Megane Touzet,
Xiao Qing Lewell, John G Emery, Hilary Schenck Eidam, John David Harling, and Niall A Anderson
ACS Med. Chem. Lett., Just Accepted Manuscript • DOI: 10.1021/acsmedchemlett.9b00219 • Publication Date (Web): 14 Jun 2019
Downloaded from http://pubs.acs.org on June 15, 2019
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Targeting IRAK4 for Degradation with PROTACs
Joao Nunes,1 Grant A. McGonagle,1 Jessica Eden,1 Girieshanie Kiritharan,1 Megane Touzet,1 Xiao
Lewell,1 John Emery,2 Hilary Eidam,2 John D. Harling,1 Niall A. Anderson1*
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1Protein Degradation Discovery Performance Unit, GlaxoSmithKline Medicines Research Centre, Gunnels Wood Road,
Stevenage, SG1 2NY, UK
2GlaxoSmithKline, King of Prussia, Pennsylvania 19406, United States
KEYWORDS: IRAK4, PROTAC, Scaffolding role, Degradation
ABSTRACT: Interleukin-1 Receptor-Associated Kinase 4 (IRAK4) is a key mediator of innate immunity. IRAK4 overactivation is
linked with several autoimmune diseases. To date, many IRAK4 inhibitors have been developed to block the protein’s kinase activity
with the most advanced reaching Phase II clinical trials. Nevertheless, several reports suggest kinase activity is not disease-relevant
in certain cell types, so removing scaffolding signalling in addition to IRAK4 kinase activity may offer a better therapeutic outcome.
Herein we describe the design and synthesis of an IRAK4 Proteolysis Targeted Chimera (PROTAC). We show that IRAK4
degradation induced by compound 9 leads to the inhibition of multiple cytokines in PBMCs. However, in IL-1 stimulated human
dermal fibroblasts, inhibition of IL-6 and TNF- release was not observed despite IRAK4 degradation. Nonetheless, the possibility
of targeting both IRAK4 kinase and scaffolding function could potentially lead to new therapeutic opportunities to treat autoimmune,
inflammatory and oncological diseases.
Introduction Interleukin-1 Receptor-Associated Kinase 4
(IRAK4) belongs to a family of four kinases (IRAK4, IRAK1,
IRAK2 and IRAK-M). IRAK4 is a serine/threonine kinase that
is involved in transduction pathways stimulated by the Toll-like
strategies to remove IRAK4 protein could offer an attractive
therapeutic opportunity for diverse disease indications.
Multiple potent and selective inhibitors of IRAK4 have been
reported in the literature targeting autoimmune, inflammatory and
receptors (TLRs) and the Interleukin-1 (IL-1) family of
9
oncological diseases.8, To date, three molecules have reached
2
receptors.1,
Recognition of foreign pathogens and
clinical trials with the most advanced being the isoquinoline ligand
PF-06650833 (Fig. 1).10 However, inhibiting IRAK4 kinase
activity alone may not be sufficient to produce a therapeutic effect
due to the role of IRAK4 as both a scaffolding protein as well as an
active kinase.
inflammatory signals by these receptors promotes IRAK4
binding to the adapter protein myeloid differentiation primary
response gene (88) (MyD88) resulting in IRAK4 activation that
in turn leads to the production of pro-inflammatory cytokines
via the NF pathway.3 IRAK4 deficiency or loss of function
has been reported to increase susceptibility to several pathogens
whilst kinase activation has been linked with various
autoimmune diseases such as systemic lupus erythematosus,
5
psoriasis, rheumatoid arthritis and cancer.4, Interestingly,
IRAK4 regulation of downstream processes has been mainly
associated with its kinase function, however several reports
have indicated a non-kinase function for IRAK4 in several cell
types.4, 6 Cushing et al showed that pharmacological inhibition
of IRAK4 did not result in IL-6 and TNF- inhibition despite
IRAK4 phosphorylation levels being reduced in IL-1β
stimulated human dermal fibroblasts.7 In support of these
observations, IRAK4 deficient fibroblasts versus wild-type
cells show IRAK4 scaffolding functions were important for IL-
1 signaling but that its kinase role was redundant.6 Chiang and
co-workers showed that IRAK4 kinase activity was dispensable
in human B and T cells, dendritic and monocytic cells, whereas
genetic ablation by siRNA demonstrated a scaffolding role for
IRAK4 in these cells.4 In addition, IRAK4 knockout mice show
profound impaired cellular responses to IL-1, IL-8 and TLRs
ligands.8 Together, these data indicate that the development of
Figure 1. Co-crystal structure of PF-06650833 with IRAK4 kinase
domain showing solvent exposed vector at 4-position of
isoquinoline core (PDB 5UIU).
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The heterobifunctional molecules referred to as proteolysis
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The six heterobifunctional compounds were then assayed to
confirm retention of IRAK4 kinase domain binding, as well as
selectivity versus the closely related IRAK1 protein (Fig. 2b).17
Gratifyingly, all compounds tested maintained affinity and
selectivity for IRAK4, with the assay variability confounded by
poor physicochemical properties.
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targeting chimeras (PROTACs), were identified as promoters
of cellular protein degradation in 2001.11,12 PROTACs contain
one moiety that binds an E3 ligase and another that binds a
desired cellular target protein of interest. PROTAC-induced
proximity results in ubiquitination of the target followed by its
degradation by the proteasome. One of the key differences of a
PROTAC over an inhibitor is that by removing all protein
function, there is the potential to achieve more profound
pharmacology than by inhibiting a functional binding site.13
Herein, we describe the design and development of PROTACs
that induce the degradation of IRAK4.
The ability of these PROTACs to reduce IRAK4 protein levels
was then tested in peripheral blood mononuclear cells
(PBMCs). The carbon linked VHL PROTAC (compound 3)
induced 50% degradation at 3 M (Fig. 3a). Importantly, the E3
ligase dependence upon degradation was confirmed using a
VHL-non-binding enantiomeric control, which after inverting
the three stereocentres is unable to recruit the VHL ligase18 and,
as expected, afforded no degradation of IRAK4 (Fig. 3b). The
other five PROTACs tested (compounds 2, 4-7) had no effect
on cellular IRAK4 levels (see supplementary Information: Fig.
S1). The PEG linked VHL PROTAC (compound 2) is less
lipophilic than the carbon analogue (compound 3), which may
suggest that poor permeability was the reason for the lack of
degradation observed with this molecule. For the CRBN and
IAP PROTACs, there are many potential reasons why these
were not found to degrade IRAK4. For example, the linker may
be the wrong length to facilitate efficient ternary complex
formation. The orientation of the protein-CRBN / IAP E3 ligase
ternary complex may also not be able to promote efficient
ubiquitin transfer onto an IRAK4 surface lysine residue.
Finally, even though these compounds may bind to the protein,
this does not always translate into degradation, as has been
observed previously in promiscuous kinase PROTAC
experiments with both VHL and CRBN E3 ligase binders.14
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Results and Discussion We evolved a synthetic strategy for
PROTAC design that facilitated variations in both E3 ligase
ligands and linker properties and allowed rapid assessment of
the degradation profiles of PROTAC analogues. To prepare
IRAK4 degrader compounds, we chose to incorporate a
chemical template related to PF-06650833 that was known to
potently bind the IRAK4 kinase domain,10 and to attach this to
either a Von Hippel Lindau (VHL) E3 ligase ligand, a Cereblon
(CRBN) E3 ligase ligand, or a ligand to the Inhibitor of
Apoptosis (IAP) E3 ligases. Three separate E3 ligases were
employed, as engagement of a given ligase does not always
translate into functional degradation.14 Using published crystal
structures of IRAK4 in complex with kinase inhibitors, we were
able to perform small molecule docking studies to predict the
best position to attach our linkers such that critical binding
interactions with the target were not disrupted. Based on our
modelling, we initially evaluated two flexible twelve atom
linkers as this was predicted to be sufficient length to exit the
IRAK4 binding site, and in an initial survey of the potential
physicochemical space, we chose the hydrophilic polylethylene
glycol (PEG) as well as the hydrophobic all-carbon chain (Fig.
2a).15, 16
a)
O
O
K2CO3, XPhos
Pd2(dba)3, DMA
HN
HN
O
O
(
O
O
O
O
N
N
X
X
H2N
H2N
(
)
2X
)
2
( X
Br
X
X = O / C
O
( X
)
1
= E3 Ligase Ligand
2
HN
X
S
)
O
H
2
H
N
N
O
N
N
X
O
O
N
O
H
H
O
N
HN
N
O
O
N
HN
O
O
O
OH
VHL
Cereblon
IAP
b)
Compound
X
-
E3 Ligase
-
IRAK4 IC50 (nM) IRAK1 IC50 (nM)
ChromLogD7.4
D max
1
2
3
4
5
6
7
2.1
0.29
0.099
nt
> 10,000
> 10,000
> 10,000
nt
2.1
3.18
5.82
nt
6.01
3.79
6.56
O
C
O
C
O
C
VHL
VHL
CRBN
CRBN
IAP
0%
50% at 3 M
0%
2.5
0.022
21
> 10,000
> 10,000
6943
0%
0%
0%
IAP
Figure 2: Approach to IRAK4 PROTACs. a) Linking VHL, CRBN and IAP E3 ligase ligands to simplified IRAK4 ligand through either a
carbon or PEG chain to generate IRAK4 PROTACs. b) Table comprising PROTAC binding affinity and lipophilicity as determined by
Chrom LogD. nt = not tested, D max = maximum degradation observed.
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Next, we sought to investigate the IRAK4 potential kinase
a)
Compound 3
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8
independent role in TLR mediated signalling. For this purpose,
the IRAK4 ligand (PF-06650833), the tool IRAK4 PROTAC
(compound 9) and the inactive control (compound 9-ve) were
monitored for cytokine inhibition upon TLR7/8 stimulation in
PBMCs. All compounds were capable of completely blocking
IL-6 secretion (Fig. 5a) as well as a wider panel of cytokines
(Fig. 5b). PF-06650833 exhibited the highest potency (Fig. 5a-
b), consistent with its higher binding potency, indicating that
there was no additional potency benefit achieved through
IRAK4 PROTAC mediated degradation over kinase inhibition.
IRAK4
β-Tubulin
% IRAK4
remaining
65
50
81
80
101
100
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b)
Compound 3-ve
O
F
O
F
a)
IRAK4
HN
HN
O
O
β-Tubulin
O
O
O
O
N
N
N
H2N
H2N
Figure 3: IRAK4 degradation induced by IRAK4-VHL PROTAC.
Representative image of western blotting analysis of PBMC cells
treated with increasing amounts of compound 3 (a) and the VHL
non-binding enantiomeric control, compound 3-ve (b) over 24
hours treatment.
( )n = 9
NH
O
N
N
O
O
8
N
O
N
9
NH
HN
N
HO
O
O
HO
S
Subsequently, shorter four and six carbon atom linkers to VHL
were evaluated (see supplementary information: Fig. S2).
However, these compounds did not afford IRAK4 degradation,
presumably as a result of being too short to form a stable ternary
complex between IRAK4 and VHL proteins.
S
N
HN
N
b)
We hypothesised that a more potent IRAK4 binder could be
used to achieve greater levels of degradation for the next
iteration of PROTAC design.15 Through a previously reported
synthesis,19 we attached the fully functionalised fluoro / ethyl
lactam present in PF-06650833 onto the IRAK4 PROTAC
warhead to prepare compound 8 (Fig. 4a). This compound
afforded more potent IRAK4 degradation compared to 3 as
observed by Western blot, with a DC50 in PBMC cells of 259
nM (Fig. 4b and Fig. S3). Following a short optimisation effort
focussing on polarity and flexibility, we modified the 12-atom
carbon linker to the VHL E3 ligase binder to a more rigid, polar
spirocyclic pyrimidine. Pleasingly, compound 9 demonstrated
increased potency with a DC50 of 151 nM in PBMC cells in
addition to lower in vitro clearance in human and rat liver
microsomes (Fig. 4a-b). As previously shown (Fig. 3), no
IRAK4 degradation was observed when cells were treated with
a VHL-non-binding enantiomeric control (9-ve)18 (Fig. S4b). In
addition, based on the kinome selectivity profile of the IRAK4
ligand,10 the extent of degradation of IRAK1 and LRRK2 was
measured with compound 9. Our data shows that similar effects
were observed with both the ligand and compound 9, supporting
literature evidence that ligand binding does not necessarily
translate into degradation14 (Fig. S4c-d).
c)
To confirm that IRAK4 degradation was proteasome
dependent, PBMCs were pre-treated with epoxomicin before
compound addition. Figure 4c shows that IRAK4 levels are
unchanged vs. DMSO treated cells, suggesting that IRAK4
PROTAC-mediated degradation is occurring in a proteasome
dependent manner.13 Inhibition of the proteasome by
epoxomicin is confirmed by the accumulation of p21 protein
levels.
Figure 4: IRAK4 PROTAC mediated degradation requires ternary
complex formation and proteasome activity. a) PROTAC
optimisation of IRAK4 warhead and linker to identify compound 9
b) Comparison of compound properties between compound 8 and
9. c) PBMCs treated with 10 µM of epoxomicin for 2 hours prior
the addition of compound 9 for a further 22 hours.
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Figure 5: IRAK4 phenotypic signalling. a - b) PBMCs were pre-treated for 18 hours with PF-06650833, compound 9 or compound
9-ve followed by 8 hours stimulation with R848 (2.5 µg/ml), cytokine levels were determined using MSD technology. c) Western
blotting of dermal fibroblast treated with compound 9 for 24 hours; d) Secreted IL-6 levels from dermal fibroblast following 18 hours
pre-treatment with 300 nM of each compound followed by 8 hours stimulation with IL-1β (10 ng/ml). n=4 ± SE.
Finally, we sought to investigate whether our PROTAC could
replicate the reported findings that IRAK4 non-kinase functions
were critical for cytokine secretion in human dermal
fibroblasts.7 Firstly, we determined that compound 9 was able
to induce a reduction of IRAK4 protein levels with a DC50 = 36
nM in this cell type (Fig. 5c). Compound 9, compound 9-ve and
PF-06650833 were then added to dermal fibroblasts followed
by IL-1β stimulation. However, we did not observe any
inhibition of IL-6 secretion upon PROTAC treatment (Fig. 5d).
This result contrasts with previous reports that showed that IL-
6 levels were completely abrogated in IRAK4 deficient dermal
fibroblasts.7 A plausible explanation could be related to the
origin of the fibroblast cells tested, as different donors may
respond differently to similar stimulation. Additionally, since
IRAK4-null fibroblasts never expressed IRAK4, we could
hypothesise that signalling patterns such as MyD88 and IRAK1
or its downstream pathways such as NF- and MAPK are not
responsive to IL-1R signalling in these cells, whereas
temporary removal of IRAK4 protein by a PROTAC isn’t
sufficient to attenuate this pathway. There is also the possibility
that the remaining portion of IRAK4 in the cell that isn’t
degraded by a PROTAC is sufficient to drive IL-1R responses.
In summary, we report a small molecule PROTAC approach
achieving potent intracellular degradation of the kinase IRAK4.
The PROTAC-induced IRAK4 degradation is dependent on
binding to VHL, and is reversed upon blocking proteasome
activity. However, compound 9 was not found to possess a
differentiated pharmacological profile over PF-06650833 in a
phenotypic assay measuring a variety of inflammatory
cytokines (Fig. 5b). In addition, the IRAK4 knockout
phenotype reported with dermal fibroblasts could not be
reproduced with compound 9 (Fig. 5d). Therefore, more work
is required to understand the biology of this target. It is clear
however, that development of new modalities such as
PROTACs to target IRAK4 may not only support the
understanding of IRAK4 biology but could also lead to the
development of new therapeutic agents to treat inflammatory
and oncological disease.
ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge on the
ACS Publications website at DOI: XXX.
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General experimental information; full synthetic procedures
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and characterisation data for all new compounds; NMR and
LC-MS data. Experimental procedures for cell culture, PBMC
isolation from blood, degradation assay, Western blotting and
cytokine analysis.
6.
Qin, J.; Jiang, Z.; Qian, Y.; Casanova, J. L.; Li, X.,
IRAK4 kinase activity is redundant for interleukin-1 (IL-1)
receptor-associated kinase phosphorylation and IL-1
responsiveness. The Journal of biological chemistry 2004, 279
(25), 26748-53.
All animal studies were ethically reviewed and carried out in
accordance with Animals (Scientific Procedures) Act 1986 and
the GSK Policy on the Care, Welfare and Treatment of
Animals.
7.
Cushing, L.; Stochaj, W.; Siegel, M.; Czerwinski,
R.; Dower, K.; Wright, Q.; Hirschfield, M.; Casanova, J. L.;
Picard, C.; Puel, A.; Lin, L. L.; Rao, V. R., Interleukin 1/Toll-
like receptor-induced autophosphorylation activates interleukin
1 receptor-associated kinase 4 and controls cytokine induction
in a cell type-specific manner. The Journal of biological
chemistry 2014, 289 (15), 10865-75.
9
AUTHOR INFORMATION
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Corresponding Author
*E-mail: niall.a.anderson@GSK.com. Phone +441438 762631
ORCID
8.
Wang, Z.; Wesche, H.; Stevens, T.; Walker, N.; Yeh,
W. C., IRAK-4 inhibitors for inflammation. Current topics in
medicinal chemistry 2009, 9 (8), 724-37.
9.
Chaudhary, D.; Robinson, S.; Romero, D. L., Recent
Niall Anderson: 0000-0001-8403-9698
advances in the discovery of small molecule inhibitors of
interleukin-1 receptor-associated kinase 4 (IRAK4) as a
therapeutic target for inflammation and oncology disorders.
Journal of medicinal chemistry 2015, 58 (1), 96-110.
Author contributions: The manuscript was written by N.A.A,
J.N and G.A.M. All authors have given approval to the final
version of the manuscript.
10.
Lee, K. L.; Ambler, C. M.; Anderson, D. R.; Boscoe,
Conflict of Interest: The authors are employees and
B. P.; Bree, A. G.; Brodfuehrer, J. I.; Chang, J. S.; Choi, C.;
Chung, S.; Curran, K. J.; Day, J. E.; Dehnhardt, C. M.; Dower,
K.; Drozda, S. E.; Frisbie, R. K.; Gavrin, L. K.; Goldberg, J.
A.; Han, S.; Hegen, M.; Hepworth, D.; Hope, H. R.;
Kamtekar, S.; Kilty, I. C.; Lee, A.; Lin, L. L.; Lovering, F.
E.; Lowe, M. D.; Mathias, J. P.; Morgan, H. M.; Murphy, E.
A.; Papaioannou, N.; Patny, A.; Pierce, B. S.; Rao, V. R.;
Saiah, E.; Samardjiev, I. J.; Samas, B. M.; Shen, M. W. H.;
Shin, J. H.; Soutter, H. H.; Strohbach, J. W.; Symanowicz, P.
T.; Thomason, J. R.; Trzupek, J. D.; Vargas, R.; Vincent, F.;
Yan, J.; Zapf, C. W.; Wright, S. W., Discovery of Clinical
Candidate 1-{[(2S,3S,4S)-3-Ethyl-4-fluoro-5-oxopyrrolidin-2-
yl]methoxy}-7-methoxyisoquinoli ne-6-carboxamide (PF-
06650833), a Potent, Selective Inhibitor of Interleukin-1
Receptor Associated Kinase 4 (IRAK4), by Fragment-Based
Drug Design. Journal of medicinal chemistry 2017, 60 (13),
5521-5542.
shareholders of GlaxoSmithKline.
Acknowledgments
We would like to thank Afjal Miah and Ian Smith for helpful
chemistry discussions, Jane Denyer and Zuni Bassi for biology
support, and Sebastien Campos and Andrew Benowitz for
reviewing the manuscript.
REFERENCES
1.
Nature reviews. Immunology 2004, 4 (7), 499-511.
2. Brzezinska, A. A.; Johnson, J. L.; Munafo, D. B.;
Akira, S.; Takeda, K., Toll-like receptor signalling.
Ellis, B. A.; Catz, S. D., Signalling mechanisms for Toll-like
receptor-activated neutrophil exocytosis: key roles for
interleukin-1-receptor-associated
phosphatidylinositol 3-kinase but not Toll/IL-1 receptor (TIR)
domain-containing adaptor inducing IFN-beta (TRIF).
Immunology 2009, 127 (3), 386-97.
kinase-4
and
11.
Sakamoto, K. M.; Kim, K. B.; Kumagai, A.;
Mercurio, F.; Crews, C. M.; Deshaies, R. J., Protacs: chimeric
molecules that target proteins to the Skp1-Cullin-F box
complex for ubiquitination and degradation. Proceedings of the
National Academy of Sciences of the United States of America
2001, 98 (15), 8554-9.
3.
O'Neill, L. A., The interleukin-1 receptor/Toll-like
receptor superfamily: 10 years of progress. Immunological
reviews 2008, 226, 10-8.
4.
Chiang, E. Y.; Yu, X.; Grogan, J. L., Immune
12.
Schneekloth, J. S., Jr.; Fonseca, F. N.; Koldobskiy,
complex-mediated cell activation from systemic lupus
erythematosus and rheumatoid arthritis patients elaborate
different requirements for IRAK1/4 kinase activity across
human cell types. Journal of immunology (Baltimore, Md. :
1950) 2011, 186 (2), 1279-88.
M.; Mandal, A.; Deshaies, R.; Sakamoto, K.; Crews, C. M.,
Chemical genetic control of protein levels: selective in vivo
targeted degradation. Journal of the American Chemical Society
2004, 126 (12), 3748-54.
13.
Bondeson, D. P.; Mares, A.; Smith, I. E.; Ko, E.;
5.
Ngo, V. N.; Young, R. M.; Schmitz, R.; Jhavar, S.;
Campos, S.; Miah, A. H.; Mulholland, K. E.; Routly, N.;
Buckley, D. L.; Gustafson, J. L.; Zinn, N.; Grandi, P.;
Xiao, W.; Lim, K. H.; Kohlhammer, H.; Xu, W.; Yang, Y.;
Zhao, H.; Shaffer, A. L.; Romesser, P.; Wright, G.; Powell,
J.; Rosenwald, A.; Muller-Hermelink, H. K.; Ott, G.;
Gascoyne, R. D.; Connors, J. M.; Rimsza, L. M.; Campo, E.;
Jaffe, E. S.; Delabie, J.; Smeland, E. B.; Fisher, R. I.; Braziel,
R. M.; Tubbs, R. R.; Cook, J. R.; Weisenburger, D. D.; Chan,
W. C.; Staudt, L. M., Oncogenically active MYD88 mutations
in human lymphoma. Nature 2011, 470 (7332), 115-9.
Shimamura, S.;
Bergamini, G.;
Faelth-Savitski, M.;
Bantscheff, M.; Cox, C.; Gordon, D. A.; Willard, R. R.;
Flanagan, J. J.; Casillas, L. N.; Votta, B. J.; den Besten, W.;
Famm, K.; Kruidenier, L.; Carter, P. S.; Harling, J. D.;
Churcher, I.; Crews, C. M., Catalytic in vivo protein
knockdown by small-molecule PROTACs. Nature chemical
biology 2015, 11 (8), 611-7.
ACS Paragon Plus Environment

ACS Medicinal Chemistry Letters
Page 6 of 6
14.
Bondeson, D. P.; Smith, B. E.; Burslem, G. M.;
S., Discovery of a Small-Molecule Degrader of Bromodomain
and Extra-Terminal (BET) Proteins with Picomolar Cellular
Potencies and Capable of Achieving Tumor Regression.
Journal of medicinal chemistry 2018, 61 (2), 462-481.
1
2
3
4
5
6
7
8
Buhimschi, A. D.; Hines, J.; Jaime-Figueroa, S.; Wang, J.;
Hamman, B. D.; Ishchenko, A.; Crews, C. M., Lessons in
PROTAC Design from Selective Degradation with
Promiscuous Warhead. Cell chemical biology 2018, 25 (1), 78-
87.e5.
a
17.
http://www.reactionbiology.com/webapps/site/.
18. Churcher, I., Protac-Induced Protein Degradation in
Reaction Biology Corp:
15.
Lai, A. C.; Toure, M.; Hellerschmied, D.; Salami, J.;
Jaime-Figueroa, S.; Ko, E.; Hines, J.; Crews, C. M., Modular
PROTAC Design for the Degradation of Oncogenic BCR-ABL.
Angewandte Chemie (International ed. in English) 2016, 55 (2),
807-10.
Drug Discovery: Breaking the Rules or Just Making New Ones?
Journal of medicinal chemistry 2018, 61 (2), 444-452.
19.
Patent, I., WO 2015150995.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
16.
Zhou, B.; Hu, J.; Xu, F.; Chen, Z.; Bai, L.;
Fernandez-Salas, E.; Lin, M.; Liu, L.; Yang, C. Y.; Zhao, Y.;
McEachern, D.; Przybranowski, S.; Wen, B.; Sun, D.; Wang,
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