Retinoic Acid Receptor-Related Orphan Receptor Î³t (RORÎ³t) Agonists

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Retinoic acid receptor-related orphan receptor-gamma-t (ROR#t) agonists as potential small molecule therapeutics for cancer immunotherapy Ruomeng Qiu, and Yonghui Wang J. Med. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jmedchem.7b01314 • Publication Date (Web): 07 Feb 2018 Downloaded from http://pubs.acs.org on February 8, 2018

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Journal of Medicinal Chemistry

Retinoic acid receptor-related orphan receptorgamma-t (RORγt) agonists as potential small molecule therapeutics for cancer immunotherapy Ruomeng Qiu, Yonghui Wang* Department of Medicinal Chemistry, School of Pharmacy, Fudan University, 826 Zhangheng Road, 201203, Shanghai, China. Keywords: cancer immunotherapy, small molecule therapeutics, RORγt agonists, mode of action

Abstract: The recent success of PD-1/PD-L1 antibodies for advanced cancer treatment has led to the conclusion that activating the immune system can be employed to fight cancer. These results also encourage the development of small molecule immuno-modulators for cancer immunotherapy. RORγt is a key transcription factor mediating Th17 cell differentiation and IL17 production, which is able to activate CD8+ T cells and elicit antitumor efficacy. Since RORγt agonists have been shown to increase basal activity of RORγt and promote Th17 cell differentiation, development of RORγt agonists could provide a unique approach to cancer immunotherapy. In this review, we summarize RORγt sterol and synthetic agonists, analyze the

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common ground of their mode of actions and discuss the potential role of RORγt agonists as small molecule therapeutics for cancer immunotherapy.

1 Introduction Cancer immunotherapy has generated inspiring clinical success recently after decades of research effort.1-3 Harnessing the human body's own immune system, cancer immunotherapy has been widely recognized as a revolutionary approach to fight cancer, either as a standalone treatment or combined with surgery, radiotherapy, chemotherapy and other established targeted therapy.4-7 In spite of contributions by other immune cell subtypes, CD8+ T cells have arisen as the prominent component in most antitumor immunity settings.8 However, one of the challenges that remain is tumor immune escape, as the activity of CD8+ T cells is down regulated in the tumor microenvironment.9,

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Multiple immunotherapeutic strategies including cytokines, vaccine,

adoptive cell transfer, and checkpoint blockades are aimed at reactivating, improving and maintaining responses by antitumor CD8+ T-cells.11-14 The recently approved antibody drugs, nivolumab and pembrolizumab as PD-1 inhibitors and atezolizumab, avelumab and durvalumab as PD-L1 inhibitors,15 have demonstrated significant efficacy and are expected to be blockbusters in the future.16 Yet considering small molecule therapeutics offer unique complementary advantages and are potentially synergistic with biologics, it is of great interest to develop alternative pathways available for small molecule intervention to boost the antitumor activity of CD8+ T cells.17, 18 T helper 17 (Th17) cells, one of T-cell subsets differentiated from naive CD4+ T cells, are characterized by unique transcription factors and IL-17 production.19 Previously, Th17 cells have


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been well described as an essential inflammatory effector and shown to promote inflammation in various autoimmune diseases.20, 21 Recent studies show that Th17 cells and IL-17 expression are broadly distributed in human tumors.22-25 It has been demonstrated that Th17 cells are actively involved in tumor immunology processes, and have potential antitumor efficacy by eliciting remarkable activation of CD8+ T cells, which makes Th17 cells a potential source of targets for cancer immunotherapy.26, 27 Retinoic acid receptor-related orphan receptor-gamma-t (RORγt) belongs to the nuclear receptor (NR) superfamily, which has provided a rich source of targets appropriate for small molecule therapeutic development of various human diseases.28 RORγt is specifically expressed by Th17 cells, and is the key transcription factor to drive naive CD4+ T cells differentiated into Th17 cells.29 Since RORγt agonists have been shown to increase basal activity of RORγt and promote Th17 cell differentiation, development of RORγt agonists could provide a unique approach to cancer immunotherapy.30 Although there have been quite a few research articles in recent years on RORγt modulators, there are no reviews focusing exclusively on RORγt agonists. This review covers the reported RORγt sterol and synthetic agonists, their mode of action and their potential role in cancer immunotherapy. Discovery progress from the first natural RORγ ligands to the most recently identified Th17 endogenous agonist of the orphan receptor RORγ has been summarized. Furthermore, we have elaborated on the published synthetic small molecule RORγt agonists, their structural insights and the common ground of their mechanism of action (MOA). Finally, we discuss the potential of small molecule RORγt agonists as novel therapeutics for cancer immunotherapy. 1.1 NR superfamily and MOA


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The NR superfamily consists of 48 transcription factors in human, including the receptors for steroid hormones, lipophilic vitamins, thyroid hormone and cholesterol metabolites.31 Approximately half of NRs are defined as orphan receptors since their ligands have not been identified. The NRs regulate a wide spectrum of physiological processes, and fairly all the identified NR ligands are developable targets for drug discovery.32 NR modulators have proven to be a rich source of pharmaceuticals, and in 2009 it was estimated that NR drugs accounted for approximately 13% of all pharmaceutical sales in the U.S. and an appreciable share of global sales.33 Nuclear receptors share a highly conserved domain that is divided into six sub-regions (regions A to F) based on sequence similarity. The structure consists of AF-1 (activation function-1) region (A/B region), followed by zinc-finger DBD (DNA binding domain) (C region), hinge domain (D region), LBD (ligand binding domain) containing the AF-2 (activation function-2) region (E region). Some receptors contain a region from LBD to the C-terminal, making up the F region. The ability of NR LBDs to trigger the transcriptional network is modulated by Helix 12 at the C-terminal.34 Helix 12 is a crucial component of the NR LBDs, because its ligand-induced reorientation contributes to the surfaces in a critical manner, recruiting or expelling coactivators /corepressors and regulating the level of transcriptional activity. Several co-crystal structures of NR LBDs have revealed that the interactions of ligands with Helix 12 significantly determine AF-2 stability. Besides, Helix 12 has intermediary positions (rather than simply being active or inactive), suggesting that ligands can be designed to have different degrees of agonism/ inverse agonism. Therefore, chemistry can generate not only receptor-specific ligands but also full or partial agonists/inverse agonists, leading to NR-based drug development. 1.2 RORγt


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The retinoic acid receptor-related orphan receptor gamma (RORγ or NR1F3) is a key NR of the ROR family, identified after RORα (RORa or NR1F1) and RORβ (RORb or NR1F2).35 RORα is most widely expressed in multiple organs, such as the liver, kidney, thymus and brain.36, 37 RORβ expression is restricted to the central nervous system.38 RORγ exists in two distinct isoforms, RORγ (RORγ1) and RORγt (RORγ2), share the identical sequence through DBD to the LBD at the C terminus, and only differ in their N-terminal sequences by only 24 amino acids.39, 40 The mRNA for RORγ is widely observed in many tissues, but RORγt isoform is mainly expressed in the immune system, especially in thymus.41 RORγt is a key transcriptional factor for Th17 cell differentiation and IL-17 production.29 Other transcription factors, including STAT3, BATF, IRF4, RUNX1, and IκBζ, also play an important role in pharmacological processes of Th17 cell differentiation. In terms of small molecule drug discovery, RORγt contains a typical-NR ligand binding domain (LBD) that binds and interacts with small molecule ligands, making it an attractive therapeutic target.42 2 RORγt agonists and their mode of actions 2.1 Sterol RORγt agonists During exploration of RORγ endogenous ligands and their role in Th17 cell differentiation, a myriad of sterols as RORγ natural ligands have been discovered, most of which serve as RORγ agonists.43-46


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Figure 1. First reported RORγ natural ligands as RORγ agonists In 2010, Jin et al reported four RORγ sterol agonists (Figure 1).43 These were the first discovered RORγ natural ligands that led to the first determined RORγ structure. To explore cholesterol and its hydroxycholesterol derivatives' role in RORγ, the interaction of RORγ with coactivator SRC1 (SRC1-2) either with or without cholesterol and hydroxycholesterols (HCs) was monitored in an AlphaScreen biochemical assay. RORα showed a high basal interaction with the SRC1-2 coactivator as a proof of concept. Ligands 1 (cholesterol), 2 (20αHydroxychloesterol), 3 (22R-Hydroxychloesterol), and 4 (25-Hydroxychloesterol) also strongly enhanced the interaction of RORγ with coactivators instead of corepressors. Besides, the EC50 of the tested hydroxycholesterols were around 0.02-0.04 µM against RORγ, compared with the EC50 of 0.02 µM for cholesterol, which was previously identified as a natural ligand of RORα. These results suggested that endogenous hydroxycholesterols played an important role in modulating RORγ-dependent biological processes.


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A

B

Figure 2. (A) 4 with RORγ LBD; (B) overlay of 2 (grey), 3 (green), and 4 (blue). PDB code: 3KYT (RORγ/2), 3L0J (RORγ/3), and 3L0L (RORγ/4). (Blue dashes represent hydrogen bond interactions). Additionally, the crystal structures of 2, 3, and 4 with RORγ LBD were resolved (Figure 2). The co-crystal complex revealed that RORγ LBD contained 12 α-helices and two short β-strands that were folded into a typical three-layer helix sandwich. The coactivator (SRC2-2) adopted a two α-helix that directed hydrophobic side chains towards RORγ coactivator binding surface. The C-terminal AF-2 was positioned in the active conformation, consistent with the agonist activity results of AlphaScreen assays. These structures revealed the binding modes of hydroxycholesterols with RORγ LBD and provided the typical coactivator-recruiting conformation of RORγ.


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Figure 3. Oxysterol RORγt agonists In 2014, Soroosh et al discovered a series of oxysterols as RORγt agonists (Figure 3).44 In a RORγ-LBD Gal4 reporter assay, several oxysterols showed significant agonism activity, with 5 (27-Hydroxycholesterol), 7 (7β, 27-Hydroxycholesterol), and 8 (7-keto, 27-Hydroxycholesterol) having the best potency and efficacy. The direct binding of oxysterols with RORγ LBD was identified by a thermal shift assay and a 3H-labeled-25-Hydroxycholesterol binding assay, and promotion of coactivator recruitment and reduction of corepressor binding were observed. In murine and human primary cells, 7 and 6 (7α, 27-HC) promoted Th17 cell differentiation in a RORγt-dependent manner. More importantly, these two oxysterols, 6 and 7, were found to be specifically produced by Th17 cells. In vivo administration of 7 observed enhanced IL-17 production in mice. In CYP27A1-deficient mice, which lacked an essential enzyme for generation of these oxysterols, a significant reduction of IL-17 producing cells was observed, and it was phenotypically similar to RORγt knockout mice. These results suggested that naturally generated oxysterols acted as RORγ agonists, and the author speculates that oxysterols may potentially serve as RORγt endogenous ligands to drive IL-17 dependent immune responses.


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In 2015, Santori et al. showed that sterols were essential and sufficient to trigger the RORγdependent transcriptional network and that the RORγt ligand is a cholesterol biosynthetic intermediate in mammalian cells.45 To map the RORγ ligand biosynthetic pathway, 78 cholesterol biosynthetic intermediates were tested in a RORγ reporter assay in insect cells, and 46 of them were bioactive. Combined with over-expression, RNA interference, and genetic deletion of metabolic enzymes to investigate the RORγ-dependent transcriptional network, it was proven that the RORγ ligands could be cholesterol biosynthetic intermediates (CBI) as lanosterol downstream and zymosterol upstream. Lipids molecules bound to RORγ were analyzed by LC/MS/MS, and they had consistent molecular weights with CBIs. In addition, CBIs stabilized the RORγ LBD and promoted coactivator recruitment, which was consistent with a previous study. This study suggested that possible endogenous ligands of RORγ were methylated CBIs or related metabolites, which is a major step towards the identification of RORγ endogenous ligands.

HO COOH 9 4ACD8

A

B

C

Figure 4. (A) Chemical structure of 4ACD8 (9); (B) RORγt-9 co-crystal structure; (C) key interactions of RORγ LBD with 9 (blue dashes represent hydrogen bond interactions).


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Furthermore, the co-crystal complex of 9 (4α-carboxy-4β-methyl-zymosterol, 4ACD8) with RORγ was obtained (PDB: 4S14) (Figure 4). In the RORγ-9 co-crystal structure, Helix 12 showed an agonism-like conformation, packed tightly to the LBD surface, and directly interacted with the coactivator. The co-crystal structure displayed a well-organized arrangement of 4ACD8 (9) in the RORγ LBD with the carboxy group of 9 interacting with RORγ residues (Q286, L287). These interactions ensured the universal binding affinity of CBIs to RORγ, similar to those of previously studied RORγ agonists.

H

H H H

H HO

H

HO

H 10, Zymosterol EC 50 = 0.11 µM

11, Desmosterol EC 50 = 0.08 µM

Figure 5. Structures of 10 (zymosterol) and 11 (desmosterol) In 2015, Hu et al confirmed that 11, a sterol produced after CYP51 demethylation, is an endogenous RORγ agonist (Figure 5).46 To identify whether precursors of cholesterol bind to RORγ and induce coactivator recruitment, a set of sterols were tested in RORγ coactivator recruitment profiling with ursolic acid added. Among these sterols, 10 and 11, two late-stage cholesterol precursors significantly promoted coactivator recruitment with EC50 values of 0.11 µM and 0.08 µM, respectively. In addition, 10 and 11 boosted IL-17 production in Th17 cell differentiation. Levels of selected sterols in Th17 cells were measured by LC/MS/MS. Only cholesterol and desmosterol were detectable among the tested sterols. Since cholesterol was unable to be generated by enzymes expressed in Th17 cells, it can be confirmed that desmosterol is an endogenous ligand in Th17 cells.


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2.2 Synthetic RORγt agonists

Figure 6. Structures of 12 (T0901317) and 13 (SR1078) In 2010, Scripps Florida disclosed compound 13, the first published synthetic small molecule as a RORγ agonist (Figure 6).47 13 was discovered from a series of compounds derived from 12, the previously identified inverse agonist of RORα/RORγ. By slightly changing from N-phenyl benzenesulfonamide to N-phenyl benzamide, 12 and 13 displayed opposite activity and different degrees of selectivity. 13 functioned as a RORα/γ agonist while 12 functioned as a RORα/γ inverse agonist; in addition, 12 has promiscuous activity by modulating RORα, RORγ, LXR and FXR, while 13 selectively modulated RORα/γ receptors, which indicated a high potential of 13 to be a chemical probe for RORα/γ function. In the AlphaScreen assay, 13 functioned as a ROR agonist on full-length RORα/γ. The agonism of 13 was further confirmed in HepG2 cells at 10 µM. The pharmacodynamics (PD) profile of 13 was also evaluated by i.p. administration at 10 mg/kg in mice, and increasing G6 Pase and FGF21 mRNA level were detected in harvested mice livers, which was consistent with the fact that 13 functioned as a RORα/γ agonist. It is worth mentioning that 13 activates the receptor beyond the normal level, along with 12, indicating the possibility of developing synthetic small molecules to suppress or further activate ROR receptors.


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Figure 7. Aryl amides as RORγ agonists In 2012, GSK accidentally discovered a class of aryl amides as RORγ agonists while screening for RORγ small molecule inhibitors (Figure 7).48 The representative three aryl amide compounds (14-16) displayed their activities with an EC50 of ~0.1 µM in IL-17 reporter assay. The three agonists also elevated thermal stability by ~3 °C, indicating that these compounds directly bind to RORγ. Compound 15 promoted IL-17 production in a mouse Th17 cell differentiation assay with the maximum response of 220% at 3 µM, which further confirmed that RORγ activation and downstream biological effects were induced by these compounds.

Figure 8. Discovery of tertiary amines as RORγt modulators


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A

B

Figure 9. (A) RORγ co-crystal structure with agonist 18; (B) key interactions of RORγ LBD with 18 (blue dashes represent hydrogen bond interactions and pink dashes represent π–π stacking interactions) In 2014, Wang and colleagues at GSK discovered a novel series of tertiary amines ranging from RORγt agonist to inverse agonists (Figure 8).49 SAR explorations starting from inverse agonist 17 yielded a tertiary amine 18 as a potent RORγt agonist with an EC50 of 0.02 µM in a RORγ dual FRET assay. A co-crystal structure of 18 with the RORγ LBD was obtained (PDB: 4NIE), and the overall binding mode was essentially the same as previously predicted (Figure 9). Two hydrogen bond interactions of the sulfonyl group with Arg367 and the linker amide with a backbone carbonyl residue were observed. Furthermore, the sulfonyl-phenyl ring and the middle phenyl ring formed π-π stacking interactions with Phe377 and Phe378, respectively. Notably, the left-hand side (LHS) benzyl group occupied the hydrophobic pocket around Trp317 and Tyr502, the key site for stabilizing Helix 12.


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Initiated from agonist 18, a series of tertiary amines with different sizes of 4-substituted moieties on LHS phenyl ring were designed, synthesized and biologically evaluated in both a RORγ dual FRET assay and FRET assay. As the size of the substitution increased (compounds 18-20), maximum activation of the compounds decreased as indicated in a RORγ dual FRET assay. When the size of the LHS substituents was further enlarged, compound 21 did not affect the basal activity of RORγt and could be regarded as a neutral antagonist. Futhermore, compounds 22-24 could be considered inverse agonists according to the increased level of inhibition indicated in the RORγ FRET assay. The activity results together with the co-crystal structure revealed a typical RORγ mode of action. The strong association between substituent bulkiness and the inhibition level could be interpreted as differing sizes of LHS moieties push away H12 to different degrees, thus influencing the ability of coactivator and corepressor recruitment at different levels. Notably, in contrast to the stepwise inhibition variation, the potency was barely influenced by substituent size. Further evaluation of 23 was performed by peptide recruitment in a RORγ dual FRET assay. Consequently, neither coactivator nor corepressor was recruited by RORγ LBD. This was the first discovery that a certain RORγt inverse agonist did not recruit corepressors. These results need to be studied further.


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Figure 10. Thiazole amides as RORγt modulators In 2015, Wang and colleagues reported a novel series of thiazole amides as RORγt modulators (Figure 10).50 Several partial agonists were identified, and the resolved co-crystal structure of 27 with the RORγ LBD provided structural insights into the mode of action. Based on the structure of HTS hit 17, a set of compounds with different 5-substitutions on the thiazole ring were evaluated in both RORγ FRET and dual FRET assays. Small alkyl moieties such as Me (25) and Et (26) did not affect RORγt activity as seen in either FRET or dual FRET assays. However, the bulky group such as phenyl (27) showed decreased maximum inhibition in RORγ FRET assay. Furthermore, 27 behaved as a partial agonist, and it activated RORγt with a pEC50 of 5.5, achieving 150% maximum activation seen in RORγ dual FRET assay. When 5-substituted moieties were changed into benzyl (28) and phenoxy (29), the compounds became inverse agonists. These results indicated a correlation between RORγt partial agonism activity and the bulky phenyl moiety on this thiazole amide scaffold.

A

B


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Figure 11. (A) Co-crystal structure of RORγ LBD with 27; (B) key interactions of RORγ LBD with 27 (blue dashes represent hydrogen bond interactions and pink dashes represent π–π stacking interactions) A co-crystal structure of RORγ LBD with 27 was obtained (PDB ID: 4XT9) and showed similar interactions to the previously reported tertiary amine RORγt agonist (Figure 11)50. The sulfonyl group formed hydrogen bonds with Arg367 and Leu287, and amide NH formed hydrogen bonds with the backbone carbonyl of Phe377, respectively (blue dash in Figure 11B). π–π Stacking interactions between two phenyl rings of 27 and Phe377 and Phe388 were observed. The thiazole ring also had a π–π stacking interaction with Phe378 (pink dash in Figure 11B). The 5-thiazole phenyl group occupied the hydrophobic space near AF2 domain and thus stabilized the AF2 domain towards coactivator recruitment. The overlay of 27 with the full RORγt agonist 20-hydroxycholesterol showed that the 5-phenyl only partially occupied the hydrophobic pocket which made 27 a partial agonist. When a CH2 or O linker was added into the thiazole ring and 5-phenyl group, it pushed the phenyl group away from the hydrophobic site and thus may not be sufficient for AF2 domain stabilization, making 28 and 29 inverse agonists. Besides, addition of 2-methoxy group on the phenyl group led 30 to be a partial agonist, because the 2-methoxy moiety of 30 occupied more space in the hydrophobic site around the AF2 domain. It was demonstrated that different sizes of substituted moieties influenced the stability of H12, resulting in a functional switch only by minor structure changes.


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Figure 12. Sulfonamides as RORγt modulators In 2014, Genentech reported divergent modes of action resulting from minor structural changes from phenyl sulfonamides to benzyl sulfonamides (Figure 12).51 In the process of optimization, parallel synthesis yielded the pair of benzyl sulfonamide 32 and phenyl sulfonamide 33, which was derived from inverse agonist 31. In a RORγ SRC1 recruitment assay, benzyl sulfonamide 32 exhibited inverse agonist activity with an IC50 of 0.015 µM, while phenyl sulfonamide 33 showed agonist activity with an EC50 of 0.25 µM.


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Figure 13. Co-crystal structure inverse agonist 31 (purple) and agonist 33 (green) with RORγ LBD Co-crystal structures of inverse agonist 31 (PDB ID: 4WQP) and agonist 33 (PDB ID: 4WPF) with the human RORγ LBD were solved (Figure 13). From an overlay of the two complexes, it was found that the two ligands almost identically overlapped from the acetyl group through the middle phenyl ring. The compounds then oriented divergently. The terminal phenyl group of the agonist ligand 33 interacted with Trp317, His479, and Tyr502, stabilizing Helix 12 in an agonistlike conformation, while the benzyl group of the inverse agonist 31 disrupted the His479-Tyr502 hydrogen bond near Helix 12. This observation provided an explanation for 31 behaving in an inverse agonist manner. Moreover, in the inverse agonist 31 complex, the Helix 11 C-terminal bent inward by 16°, while aromatic side chains rotated and the pocket apex was repacked in the absence of Helix 12. Trp317 and Phe486 also re-orientated and the filled pockets formed following these changes. These switch-like motions explained how inverse agonist 31 interfered with Helix 11 and Helix 12, leading to inverse agonism activity.


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O

O O N

O S F3 C

F O

N H Cl

O

N S

F HN

O

F 34 inverse agonist

35 agonist

Figure 14. Benzoxazepine benzamides as RORγt modulators

A

B

Figure 15. (A) Superposition of soak-in crystal structures of 34 (purple) and 35 (green); (B) Superposition of co-crystal structure of 34 (red) and soak-in crystal structure of 35 (green) In 2016, a series of benzoxazepine benzamides as RORγt modulators were disclosed by AstraZeneca (Figure 14).52 The opposite behaviors induced by slightly modified compounds were also observed. In a cofactor recruitment assay, most compounds behaved as potent and selective RORγt inverse agonists, whereas five compounds behaved as RORγt agonists, promoting coactivator recruitment with efficacy up to 58% at a concentration of 1 µM. The soaked-in crystal structures of inverse agonist 34 and agonist 35 with RORγ-LBD were solved (PDB:5APJ and 5APH, respectively). However, the binding modes were similar and could not provide a solid explanation for the different mode of actions (Figure 15A). To identify the


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potential triggers for the inverse agonism of compound 34, co-crystallization with the RORγ LBD without a coactivator peptide was carried out (PDB: 5APK) (Figure 15B). In this way, a different binding mode of inverse agonist 34 was identified. The NH of the benzamide group formed a hydrogen bond interaction with His479, effectively disturbing the His479-Tyr502 agonist lock, which was a crucial interaction for maintaining the agonist conformation. Additionally, an induced fit binding mode was discovered, in which Helix 11 residues formed a pocket around the halogen-substituted benzamide group. The induced-fit binding like mode of action has never been observed in previously reported inverse agonist co-crystal structures, and the detailed mechanism of achieving inverse agonism required further exploration.

Figure 16. Benzoxazinones as RORγt modulators

Figure 17. Overlay of inverse agonist 36 (BIO399, purple) and agonist 37 (BIO592, green)


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In 2016, Biogen reported benzoxazinone as RORγt modulators including an inverse agonist 36 and an agonist 37 (Figure 16).53 Having similar chemical scaffold, 36 was only 3 atoms larger compared to the benzo [1,4] oxazine-3-one ring of 37. To investigate how minor differences lead to inverse agonism, an X-ray crystallography study was carried out and their co-crystal structures with full-length or partial proteolysed RORγ were solved (PDB: 5IXK and 5IZ0, respectively) (Figure 17). The agonist-bound construct showed that the agonist conformation was stabilized by His479-Tyr502 hydrogen bond, which was critical for agonist conformation. Next, cocrystallization with the inverse agonist 36 and RORγ518 was attempted but did not produce any crystals. By using RORγ518 with proteolyzed AF2 helix, the inverse agonist-bound construct was obtained. Together with the co-crystal structure of 37, it can be concluded that the agonist conformation of the co-crystal structure of 37 would be perturbed by Met358 and pushed by BIO399 into Phe506 of AF2 domain, suggesting that Met358 positioning is crucial for triggering RORγ inverse agonism.

Figure 18. 13 and its analog 38 (SR0987) In 2016, Scripps reported 38, discovered from SAR exploration of the first identified RORγt agonist 13 (Figure 18).30 Using desmosterol as a control for agonism, the efficacy of 13 as a RORγt agonist was determined in a Gal4 reporter assay. In the same system, 38 resulted in a further increase in the expression of IL-17. Unexpectedly, treatment with 38 also led to a decrease in the expression of PD-1 without impact on the expression of granzyme B (cytotoxicity


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marker). Together, these results suggested that treatment with 38 may enhance protective immunity by regulating the expression of IL-17 and PD-1 while maintaining the cytotoxic ability of these cells. And this hypothesis was also validated by a Th17 cell differentiation assay using Jurkat T cells. The discovery of dual function of anti-PD-1 and T cell activation of RORγt agonists may provide with a unique approach to cancer immunotherapy. To study the mode of action in view of structural insights, hydrogen/deuterium exchange (HDX) mass spectrometry was applied with desmosterol, 13 and 38. When treated with either 13 or 38, protection to solvent exchange was also observed in H12, but was not observed with desmosterol. This phenomenon was consistent with the stabilized conformation of H12 in previously reported co-crystallization structures, and it provided an explanation for why 38 acted as a RORγt agonist.

Figure 19. N-arylsulfonyl indolines as RORγ agonists Doebelin et al from the Scripps Institute reported a series of N-arylsulfonyl indolines as RORγ agonists (Figure 19).54 The first RORγ agonist was accidentally discovered by N-methylation of the amide linker of inverse agonist 39. Similar to previously reported mode of action studies, the linker played a major role in deciding specific pharmacology wherein a potent RORγ inverse agonist could be converted into a RORγ agonist, while the binding affinity was not much influenced. After SAR exploration of multiple linkers, ether (-CH2O-) was identified as preferred linker to exhibit RORγ agonism. Further optimization had minor effects on in vitro activity.


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HDX data was able to delineate the structural mechanism for the switch in pharmacology from an inverse agonist 39 to an agonist 40 through increased H12 stabilization, a phenomenon that was constantly observed in nuclear receptors. These RORγ agonists had poor metabolic stability probably caused by the high lipophilicity. Yet considering adequate plasma exposure following i.p. dosing, these compounds may be used as tools to investigate RORγ activation in animal tumor models.

Figure 20. Exemplary RORγt agonists in WO2015131035A1 In 2015, Lycera disclosed three patents claiming RORγt agonists.55-57 The patents provided sulfonamido and related compounds, methods of boosting RORγ activity and/or enhancing the amount of IL-17 in a subject, and methods of treating various medical disorders especially aiming at various cancers. In patent WO2015131035A1, three sulfonamido compounds (41-43) were listed as potent RORγt agonists (Figure 20) with average EC50 values under 0.5 µM in a TR-FRET assay and a Gal4 reporter assay. Adoptive transfer of Tc17 to mice EG7 tumor model and Tc17/Th17/both to mice B16F10 tumor model was exemplified, demonstrating RORγt agonist suppressing tumor growth through T-cell activation. Additionally, obvious anti-tumor efficacy was observed at the compound concentration of 5 µM to 10 µM.


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Figure 21. Representative RORγt agonists in Lycera's patents Two patents were published in 2016 by Lycera which particularly provided dihydro-2Hbenzo[b] [1,4] oxazine sulfonamide and related compounds (e.g., 46 and 47) as follow up to the 2015 patents (e.g., 44 and 45).58,

59

Compared to WO2015131035 and WO2015171610, the

exemplary compounds in WO2016201225 and WO2016179343 have similar core structures but with different left-side linkers or right-side substituents (Figure 21). Exemplary compounds were tested in a TR-FRET assay and a Gal4 RORγ assay, and the most potent compounds were less than 0.5 µM with the max response greater than 200%. Table 1. Current active projects of anticancer RORγt agonistsa

Active Companies

Active Indications

Status

Added Date

Nuevolution

Cancer

Discovery

24-Jan-2017

ROR gamma agonists Celgene Corp (oral, cancer)

Cancer

Discovery

08-Nov-2016

ROR gamma agonists Aurigene (cancer)

Cancer

Discovery

18-Dec-2015

INV-71

Innovimmune

Cancer

Discovery

20-Jan-2017

LYC-55716

Lycera Corp

Advanced solid Phase 2A tumor

Drug Name

ROR gamma agonist (cancer)

a

T

05-Jan-2017

Data retrieved from Cortellis™, Thomson Reuters.60


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In June of 2015, Celgene paid Lycera $105 million to partner with Lycera's anti-cancer T-cell technology, which was assumed by emerging evidence as orally available RORγ agonists.61 In January of 2017, the RORγ agonist named LYC-55176 from Lycera entered into Phase 2A trial (NCT02929862) and was orally dosed as a single agent for locally advanced or metastatic solid tumors.62 In addition to Lycera, several pharmaceutical companies have begun to initiate anticancer RORγ agonist projects (Table 1). Collectively, it can be concluded that synthetic RORγ agonists potentially serve as novel small molecule therapeutics for cancer immunotherapy. 3 Discussion and conclusions The NR superfamily has been considered attractive targets involved in various human diseases. Since NRs contain a conserved ligand-binding domain, they are ideal receptors for development of small molecuar ligands. As a member of the NR superfamily, many RORγt small molecule modulators have been discovered, including endogenous sterol ligands and synthetic small molecule modulators. In recent years, substantial progress has been made in the discovery of RORγt agonists, even though some studies may not be focused on agonists at first. Sterols, as first identified RORγ ligands, led to determination of the RORγ structure and initiated progress towards the identification of endogenous RORγ agonists. Synthetic RORγt agonists have been unexpectedly discovered through agonist/inverse agonist conversion, and their crystallization structures revealed similar mode of actions. Stabilization of a hydrophobic pocket formed around Trp317 and Tyr502 near H12 is crucial in recruiting coactivators and functioning in an agonistlike manner. Minor structural changes to synthetic ligands, such as enlarging substituents or changing linkers, pushed the hydrophobic pocket and disrupted the His479-Tyr502 lock, resulting in a functional switch between agonist and inverse agonist. In general, together with


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discovered RORγt modulators, recent progress of RORγt structural insights has provided key principles guiding structure-based design for discovery of synthetic RORγt agonists. Since Th17 cell differentiation and IL-17 have been demonstrated to elicit an antitumor effect by activating CD8+ T cells, RORγt, as the key lineage transcription factor to initiate the Th17 cell differentiation and IL-17 production, is considered a potential target for cancer immunotherapy. Moreover, several synthetic RORγt agonists have been shown to inhibit PD-1 expression on Th17 cells and regulate other pathways favorable to anti-tumor immunity. A recent paper reported that a RORγ antagonist has an antitumor effect on prostate cancer by acting on upstream of the androgen receptor (AR), yet this is resulted from a distinct mechanism.63 In theory, there is also the potential risk that RORγt agonists could cause autoimmune disorders, resulting from increased levels of IL-17. However, no experimental findings or clinical evidence has been reported for this side effect so far.64 Therefore, along with LYC-55716 entering into Phase 2A study, the development of RORγt agonists may provide a promising approach towards novel small molecule therapeutics for cancer immunotherapy.

AUTHOR INFORMATION Corresponding Author *(Yonghui Wang) Phone: +8621 5198 0118. E-mail: [email protected] ORCID Yonghui Wang: 0000-0002-0262-2431 Author Contributions *Yonghui Wang and Ruomeng Qiu contributed to this manuscript.


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Notes The authors declare no competing financial interest. Biographies Yonghui Wang obtained his Ph.D. in organic chemistry from Virginia Tech in 1997 and had his postdoctoral training in physical and synthetic organic chemistry at Harvard University from 1997 to 2001. He then worked in GlaxoSmithKline R&D as a principal scientist, investigator and associate director for more than 12 years. Since 2014, he has become a professor in the School of Pharmacy at Fudan University, China. His current research focuses on small molecule drug discovery for autoimmune diseases and cancer immunotherapy. He has published more than 50 scientific papers and is co-inventor of 30 PCT international patents. Ruomeng Qiu is a graduate student in medicinal chemistry under the supervision of professor Yonghui Wang at Fudan University. She earned her B.S. degree from the School of Pharmacy at Fudan University in 2015. Her research interests include discovery of novel RORγt agonists for cancer immunotherapy and phenotypic drug discovery of small molecular IL-17 suppressors. ACKNOWLEDGMENTS We thank all the present and past members of the working group that were not actively involved in this publication for the help with some of the ideas and for the stimulating discussions: Ting Tang, Yafei Huang, Mingcheng Yu, Nannan Sun, Wei Fu. We thank Professor Di Zhu for helpful discussions. We are grateful to Tony Wang and Caitlin Wang for the proof-reading of the manuscript.


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This work was supported by National Science Foundation of China (Grant No. 81573276) and Shanghai Bio-pharmaceutical Science and Technology Supporting Plan (Grant No. 15431900300). ABBREVIATIONS USED CYP51, cytochrome P450, family 51; FRET, fluorescence resonance energy transfer; HC, hydroxycholesterol; HTS, high throughput screening; IL-17, interleukin 17; LHS, left-hand side; MOA, mechanism of action; NR, nuclear receptor; PD, pharmacodynamics; PD-1, programmed death 1; PD-L1, programmed death ligand 1; RORγt, retinoic acid receptor-related orphan receptor-gamma-t; SAR, structure-activity relationship; SRC, steroid receptor coactivator; Th17 cell, T helper 17 cell.

REFERENCES (1) Balkwill, F.; Mantovani, A. Inflammation and cancer: back to Virchow? The Lancet 2001, 357, 539-545. (2) Hall, S. S. A Commotion in the Blood : Life, Death, and the Immune System, 1st ed.; Henry Holt: New York, 1997; pp 14-14. (3) Coley, W. B. II. Contribution to the knowledge of sarcoma. Annals of Surgery 1891, 14, 199-220. (4) Couzin-Frankel, J. Breakthrough of the year 2013. cancer immunotherapy. Science 2013, 342, 1432-1433. (5) Mahoney, K. M.; Rennert, P. D.; Freeman, G. J. Combination cancer immunotherapy and new immunomodulatory targets. Nat. Rev. Drug Discov. 2015, 14, 561-584.


28

Page 29 of 38 1 2 3 4 5 6 7 8 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


(6) Ishihara, D.; Pop, L.; Takeshima, T.; Iyengar, P.; Hannan, R. Rationale and evidence to combine radiation therapy and immunotherapy for cancer treatment. Cancer Immunol. Immunother., 2017, 66, 281-298. (7) Vilgelm, A. E.; Johnson, D. B.; Richmond, A. Combinatorial approach to cancer immunotherapy: strength in numbers. J. Leukocyte Biol. 2016, 100, 275-290. (8)

Jackson, S. R.; Yuan, J.; Teague, R. M. Targeting CD8+ T-cell tolerance for cancer

immunotherapy. Immunotherapy 2014, 6, 833-852. (9)

Becker, J. C.; Andersen, M. H.; Schrama, D.; Thor Straten, P. Immune-suppressive

properties of the tumor microenvironment. Cancer Immunol. Immunother. 2013, 62, 1137–1148. (10) Wayteck, L.; Breckpot, K.; Demeester, J.; De Smedt, S. C.; Raemdonck, K. A personalized view on cancer immunotherapy. Cancer Lett. 2014, 352, 113-125. (11) Boyman, O.; Kovar, M.; Rubinstein, M. P.; Surh, C. D.; Sprent, J. Selective stimulation of T cell subsets with antibody-cytokine immune complexes. Science 2006, 311, 1924-1927. (12) Pardoll, D. M. The blockade of immune checkpoints in cancer immunotherapy. Nat. Rev. Cancer 2012, 12, 252-64. (13) Rosenberg, S. A.; Restifo, N. P. Adoptive cell transfer as personalized immunotherapy for human cancer. Science 2015, 348, 62-68. (14) Palucka, K.; Banchereau, J.; Mellman, I. Designing vaccines based on biology of human dendritic cell subsets. Immunity 2010, 33, 464-478. (15) Cortellis, Thomson Reuters Database, https://cortellis.thomsonreuterslifesciences.com/


29


Page 30 of 38

(16) Collin, M. Immune checkpoint inhibitors: a patent review (2010-2015). Expert Opin. Ther. Pat. 2016, 26, 555-564. (17) Adams, J. L.; Smothers, J.; Srinivasan, R.; Hoos, A. Big opportunities for small molecules in immuno-oncology. Nat. Rev. Drug Discov. 2015, 14, 603-622. (18) Weinmann, H. Cancer immunotherapy: selected targets and small-molecule modulators. ChemMedChem. 2016, 11, 450-466. (19) Harrington, L. E.; Hatton, R. D.; Mangan, P. R.; Turner, H.; Murphy, T. L.; Murphy, K. M.; Weaver, C. T. Interleukin 17-producing CD4+ effector T cells develop via a lineage distinct from the T helper type 1 and 2 lineages. Nat. Immunol. 2005, 6, 1123-1132. (20) Komiyama, Y.; Nakae, S.; Matsuki, T.; Nambu, A.; Ishigame, H.; Kakuta, S.; Sudo, K.; Iwakura, Y. IL-17 plays an important role in the development of experimental autoimmune encephalomyelitis. J. Immunol. 2006, 177, 566-573. (21) Tesmer, L. A.; Lundy, S. K.; Sarkar, S.; Fox, D. A. Th17 cells in human disease. Immunol. Rev. 2008, 223, 87-113. (22) Kryczek, I.; Wei, S.; Zou, L.; Altuwaijri, S.; Szeliga, W.; Kolls, J.; Chang, A.; Zou, W. Cutting edge: Th17 and regulatory T cell dynamics and the regulation by IL-2 in the tumor microenvironment. J. Immunol. 2007, 178, 6730-6733. (23) Kryczek, I.; Banerjee, M.; Cheng, P.; Vatan, L.; Szeliga, W.; Wei, S.; Huang, E.; Finlayson, E.; Simeone, D.; Welling, T. H.; Chang, A.; Coukos, G.; Liu, R.; Zou, W. Phenotype, distribution, generation, and functional and clinical relevance of Th17 cells in the human tumor environments. Blood 2009, 114, 1141-1149.


30

Page 31 of 38 1 2 3 4 5 6 7 8 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


(24) Muranski, P.; Boni, A.; Antony, P. A.; Cassard, L.; Irvine, K. R.; Kaiser, A.; Paulos, C. M.; Palmer, D. C.; Touloukian, C. E.; Ptak, K.; Gattinoni, L.; Wrzesinski, C.; Hinrichs, C. S.; Kerstann, K. W.; Feigenbaum, L.; Chan, C. C.; Restifo, N. P. Tumor-specific Th17-polarized cells eradicate large established melanoma. Blood 2008, 112, 362-373. (25) Miyahara, Y.; Odunsi, K.; Chen, W.; Peng, G.; Matsuzaki, J.; Wang, R. F. Generation and regulation of human CD4+ IL-17-producing T cells in ovarian cancer. P. Natl. Acad. Sci. USA 2008, 105, 15505-15510. (26) Martin-Orozco, N.; Muranski, P.; Chung, Y.; Yang, X. O.; Yamazaki, T.; Lu, S.; Hwu, P.; Restifo, N. P.; Overwijk, W. W.; Dong, C. T helper 17 cells promote cytotoxic T cell activation in tumor immunity. Immunity 2009, 31, 787-798. (27) Hinrichs, C. S.; Kaiser, A.; Paulos, C. M.; Cassard, L.; Sanchez-Perez, L.; Heemskerk, B.; Wrzesinski, C.; Borman, Z. A.; Muranski, P.; Restifo, N. P. Type 17 CD8+ T cells display enhanced antitumor immunity. Blood 2009, 114, 596-599. (28) Maglich, J. M.; Caravella, J. A.; Lambert, M. H.; Willson, T. M.; Moore, J. T.; Ramamurthy, L. The first completed genome sequence from a teleost fish (Fugu rubripes) adds significant diversity to the nuclear receptor superfamily. Nucleic Acids Res. 2003, 31, 40514058. (29) Ivanov, II; McKenzie, B. S.; Zhou, L.; Tadokoro, C. E.; Lepelley, A.; Lafaille, J. J.; Cua, D. J.; Littman, D. R. The orphan nuclear receptor RORgammat directs the differentiation program of proinflammatory IL-17+ T helper cells. Cell 2006, 126, 1121-1133.


31


Page 32 of 38

(30) Chang, M. R.; Dharmarajan, V.; Doebelin, C.; Garcia-Ordonez, R. D.; Novick, S. J.; Kuruvilla, D. S.; Kamenecka, T. M.; Griffin, P. R. Synthetic RORgammat agonists enhance protective immunity. ACS Chem. Biol. 2016, 11, 1012-1018. (31) Burris, T. P.; Solt, L. A.; Wang, Y.; Crumbley, C.; Banerjee, S.; Griffett, K.; Lundasen, T.; Hughes, T.; Kojetin, D. J. Nuclear receptors and their selective pharmacologic modulators. Pharmacol. Rev. 2013, 65, 710-778. (32) Germain, P.; Staels, B.; Dacquet, C.; Spedding, M.; Laudet, V. Overview of nomenclature of nuclear receptors. Pharmacol. Rev. 2006, 58, 685-704. (33) Fauber, B. P.; Magnuson, S. Modulators of the nuclear receptor retinoic acid receptorrelated orphan receptor-gamma (RORgamma or RORc). J. Med. Chem. 2014, 57, 5871-5892. (34) Burris, T. P.; Busby, S. A.; Griffin, P. R. Targeting orphan nuclear receptors for treatment of metabolic diseases and autoimmunity. Chem. Biol. 2012, 19, 51-59. (35) Solt, L. A.; Burris, T. P. Action of RORs and their ligands in (patho)physiology. Trends Endocrin. Met. 2012, 23, 619-627. (36) Hamilton, B. A.; Frankel, W. N.; Kerrebrock, A. W.; Hawkins, T. L.; FitzHugh, W.; Kusumi, K.; Russell, L. B.; Mueller, K. L.; van Berkel, V.; Birren, B. W.; Kruglyak, L.; Lander, E. S. Disruption of the nuclear hormone receptor RORalpha in staggerer mice. Nature 1996, 379, 736-739. (37) Steinmayr, M.; Andre, E.; Conquet, F.; Rondi-Reig, L.; Delhaye-Bouchaud, N.; Auclair, N.; Daniel, H.; Crepel, F.; Mariani, J.; Sotelo, C.; Becker-Andre, M. Staggerer phenotype in


32

Page 33 of 38 1 2 3 4 5 6 7 8 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


retinoid-related orphan receptor alpha-deficient mice. P. Natl. Acad. Sci. USA 1998, 95, 39603965. (38) Andre, E.; Gawlas, K.; Becker-Andre, M. A novel isoform of the orphan nuclear receptor RORbeta is specifically expressed in pineal gland and retina. Gene 1998, 216, 277-283. (39) Eberl, G.; Littman, D. R. The role of the nuclear hormone receptor RORgammat in the development of lymph nodes and Peyer's patches. Immunol. Rev. 2003, 195, 81-90. (40) Isono, F.; Fujita-Sato, S.; Ito, S. Inhibiting RORgammat/Th17 axis for autoimmune disorders. Drug Discov. Today 2014, 19, 1205-1211. (41) Eberl, G.; Marmon, S.; Sunshine, M. J.; Rennert, P. D.; Choi, Y.; Littman, D. R. An essential function for the nuclear receptor RORgamma(t) in the generation of fetal lymphoid tissue inducer cells. Nat. Immunol. 2004, 5, 64-73. (42) Huh, J. R.; Littman, D. R. Small molecule inhibitors of RORgammat: targeting Th17 cells and other applications. Euro. J. Immunol. 2012, 42, 2232-2237. (43) Jin, L.; Martynowski, D.; Zheng, S.; Wada, T.; Xie, W.; Li, Y. Structural basis for hydroxycholesterols as natural ligands of orphan nuclear receptor RORgamma. Mol. Endocrinol. 2010, 24, 923-929. (44) Soroosh, P.; Wu, J.; Xue, X.; Song, J.; Sutton, S. W.; Sablad, M.; Yu, J.; Nelen, M. I.; Liu, X.; Castro, G.; Luna, R.; Crawford, S.; Banie, H.; Dandridge, R. A.; Deng, X.; Bittner, A.; Kuei, C.; Tootoonchi, M.; Rozenkrants, N.; Herman, K.; Gao, J.; Yang, X. V.; Sachen, K.; Ngo, K.; Fung-Leung, W. P.; Nguyen, S.; de Leon-Tabaldo, A.; Blevitt, J.; Zhang, Y.; Cummings, M. D.; Rao, T.; Mani, N. S.; Liu, C.; McKinnon, M.; Milla, M. E.; Fourie, A. M.; Sun, S. Oxysterols


33


Page 34 of 38

are agonist ligands of RORgammat and drive Th17 cell differentiation. P. Natl. Acad. Sci. USA 2014, 111, 12163-12168. (45) Santori, F. R.; Huang, P.; van de Pavert, S. A.; Douglass, E. F., Jr.; Leaver, D. J.; Haubrich, B. A.; Keber, R.; Lorbek, G.; Konijn, T.; Rosales, B. N.; Rozman, D.; Horvat, S.; Rahier, A.; Mebius, R. E.; Rastinejad, F.; Nes, W. D.; Littman, D. R. Identification of natural RORgamma ligands that regulate the development of lymphoid cells. Cell Metab. 2015, 21, 286297. (46) Hu, X.; Wang, Y.; Hao, L. Y.; Liu, X.; Lesch, C. A.; Sanchez, B. M.; Wendling, J. M.; Morgan, R. W.; Aicher, T. D.; Carter, L. L.; Toogood, P. L.; Glick, G. D. Sterol metabolism controls T(H)17 differentiation by generating endogenous RORgamma agonists. Nat. Chem. Biol. 2015, 11, 141-147. (47) Wang, Y.; Kumar, N.; Nuhant, P.; Cameron, M. D.; Istrate, M. A.; Roush, W. R.; Griffin, P. R.; Burris, T. P. Identification of SR1078, a synthetic agonist for the orphan nuclear receptors RORalpha and RORgamma. ACS Chem. Biol. 2010, 5, 1029-1034. (48) Zhang, W.; Zhang, J.; Fang, L.; Zhou, L.; Wang, S.; Xiang, Z.; Li, Y.; Wisely, B.; Zhang, G.; An, G.; Wang, Y.; Leung, S.; Zhong, Z. Increasing human Th17 differentiation through activation of orphan nuclear receptor retinoid acid-related orphan receptor gamma (RORgamma) by a class of aryl amide compounds. Mol. Pharmacol. 2012, 82, 583-590. (49) Yang, T.; Liu, Q.; Cheng, Y.; Cai, W.; Ma, Y.; Yang, L.; Wu, Q.; Orband-Miller, L. A.; Zhou, L.; Xiang, Z.; Huxdorf, M.; Zhang, W.; Zhang, J.; Xiang, J. N.; Leung, S.; Qiu, Y.; Zhong, Z.; Elliott, J. D.; Lin, X.; Wang, Y. Discovery of tertiary amine and indole derivatives as potent RORγt inverse agonists. ACS Med. Chem. Lett. 2014, 5, 65-68.


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Page 35 of 38 1 2 3 4 5 6 7 8 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


(50) Wang, Y.; Yang, T.; Liu, Q.; Ma, Y.; Yang, L.; Zhou, L.; Xiang, Z.; Cheng, Z.; Lu, S.; Orband-Miller, L. A.; Zhang, W.; Wu, Q.; Zhang, K.; Li, Y.; Xiang, J. N.; Elliott, J. D.; Leung, S.; Ren, F.; Lin, X. Discovery of N-(4-aryl-5-aryloxy-thiazol-2-yl)-amides as potent RORγt inverse agonists. Bioorg. Med. Chem. 2015, 23, 5293-5302 (51) Rene, O.; Fauber, B. P.; Boenig, G. d. L.; Burton, B.; Eidenschenk, C.; Everett, C.; Gobbi, A.; Hymowitz, S. G.; Johnson, A. R.; Kiefer, J. R.; Liimatta, M.; Lockey, P.; Norman, M.; Ouyang, W.; Wallweber, H. A.; Wong, H. Minor structural change to tertiary sulfonamide RORc ligands led to opposite mechanisms of action. ACS Med. Chem. Lett. 2015, 6, 276-281. (52) Olsson, R. I.; Xue, Y.; von Berg, S.; Aagaard, A.; McPheat, J.; Hansson, E. L.; Bernstrom, J.; Hansson, P.; Jirholt, J.; Grindebacke, H.; Leffler, A.; Chen, R.; Xiong, Y.; Ge, H.; Hansson, T. G.; Narjes, F. Benzoxazepines achieve potent suppression of IL-17 release in human T-Helper 17 (TH 17) cells through an induced-fit binding mode to the nuclear receptor RORgamma. ChemMedChem. 2016, 11, 207-216. (53) Marcotte, D. J.; Liu, Y.; Little, K.; Jones, J. H.; Powell, N. A.; Wildes, C. P.; Silvian, L. F.; Chodaparambil, J. V. Structural determinant for inducing RORgamma specific inverse agonism triggered by a synthetic benzoxazinone ligand. BMC Struct. Biol. 2016, 16:7. (54) Doebelin, C.; Patouret, R.; Garcia-Ordonez, R. D.; Chang, M. R.; Dharmarajan, V.; Kuruvilla, D. S.; Novick, S. J.; Lin, L.; Cameron, M. D.; Griffin, P. R.; Kamenecka, T. M. NArylsulfonyl indolines as retinoic acid receptor-related orphan receptor gamma (RORgamma) agonists. ChemMedChem. 2016, 11, 2607-2620. (55) Glick, G. D.; Toogood, P. L.; Hu, X.; Aicher, T. D.; Celeste, L. L.; Liu, X.; Taylor, C. B.; Vanhuis, C. A. Adoptive cellular therapy using an agonist of retinoic acid recepor-related orphan


35


Page 36 of 38

receptor gamma & related therapeutic methods. World Intellectual Property Organization Patent 2015,131,035, Mar 9, 2015. (56) Aicher, T. D.; Taylor, C. B.; Vanhuis, C. A. Tetrahydroquinoline sulfonamide and related compounds for use as agonists of RORγ and the treatment of disease. World Intellectual Property Organization Patent 2015,171,610, May 17, 2016. (57) Aicher, T. D.; Skalitzky, D. J.; Taylor, C. B.; Vanhuis, C. A. Benzenesulfonamido and related compounds for use as agonists of RORγ and the treatment of Disease. World Intellectual Property Organization patent 2015,171,558, Jul 20, 2017. (58) Aicher, T. D.; Taylor, C. B.; Vanhuis, C. A. Aryl Dihydro-2H-benzo[b] [1,4] oxazine sulfonamide and related compounds for use as agonists of RORγ and the treatment of disease. World Intellectual Property Organization patent 2016,201,225, Dec 15, 2016. (59) Aicher, T. D.; Taylor, C. B.; Vanhuis, C. A. Dihydro-2H-benzo[b] [1,4] oxazine sulfomide and related compounds for use as agonists of RORγ and the treatment of disease. World Intellectual Property Organization patent 2016,179,343, Nov 10, 2016. (60) Cortellis, Thomson Reuters Database: Search results for “retinoid Z receptor gamma agonist”; https://cortellis.thomsonreuterslifesciences.com/ [Jun 23, 2017] (61) News on FierceBiotech: http://www.fiercebiotech.com/biotech/lycera-s-double-actionimmuno-oncology-drug-starts-trials [Jan 4, 2017] (62) US

National

Library

of

Medicine.

ClinicalTrials.gov

https://clinicaltrials.gov/ct2/show/NCT02929862 [June 23, 2017]


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Page 37 of 38 1 2 3 4 5 6 7 8 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


(63) Wang, J.; Zou, J. X.; Xue, X.; Cai, D.; Zhang, Y.; Duan, Z.; Xiang, Q.; Yang, J. C.; Louie, M. C.; Borowsky, A. D.; Gao, A. C.; Evans, C. P.; Lam, K. S.; Xu, J.; Kung, H.; Evans, R. M.; Xu, Y.; Chen, H. ROR-γ drives androgen receptor expression and represents a therapeutic target in castration-resistant prostate cancer. Nat. Med. 2016, 22, 488-496. (64) Hu, X.; Liu, X.; Moisan, J.; Wang, Y.; Lesch, C. A.; Spooner, C.; Morgan, R. W.; Zawidzka, E. M.; Mertz, D.; Bousley, D.; Majchrzak, K.; Kryczek, I.; Taylor, C.; Van Huis, C.; Skalitzky, D.; Hurd, A.; Aicher, T. D.; Toogood, P. L.; Glick, G. D.; Paulos, C. M.; Zou, W.; Carter, L. L. Synthetic RORgamma agonists regulate multiple pathways to enhance antitumor immunity. Oncoimmunology 2016, 5, e1254854.


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Table of Contents graphic

Agonist Coactivator

RORγγt +

T-cell

IL-17

Tumor


38

Retinoic Acid Receptor-Related Orphan Receptor Î³t (RORÎ³t) Agonists

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