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Alan D Dandrea - One of the best experts on this subject based on the ideXlab platform.
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abstract 333 USP1 is required for replication fork stability in brca1 deficient tumors
Cancer Research, 2018Co-Authors: Heng Li, Emma A Roberts, Emily F Gaudiano, Connor Clairmont, Karthikeyan Ponnienselvan, Kalindi Parmar, Ning Zheng, Alan D DandreaAbstract:Homologous-recombination (HR) deficient tumors with BRCA1 and BRCA2 mutations exhibit replication fork stability defects. To date, PARP inhibitors are the only targeted therapy available in the clinic against HR deficient tumors, and alternative therapies are needed. In this study, we found a deubiquitinase, USP1, to be significantly upregulated in tumors with mutations in BRCA1. SiRNA mediated silencing or small molecule inhibition of USP1 activity resulted in replication fork destabilization and decreased viability of BRCA1 deficient cells, revealing a synthetic lethal relationship between USP1 and BRCA1. The cofactor of USP1, UAF1, had previously been shown to have DNA-binding activity. We observed that USP1 independently binds to and is stimulated by fork DNA. It is therefore the first known deubiquitinase (DUB) to be directly regulated by DNA binding. A truncated form of USP1, lacking its DNA binding region, was not stimulated by DNA and failed to localize and protect the replication fork. Persistence of monoubiquitinated PCNA at the replication fork was the mechanism of fork destabilization and cell death in the absence of USP1. Loss of monoubiquitinated PCNA, resulting from RAD18 knockdown, rescued the sensitivity and replication fork instability induced by USP1 inhibition. USP1 therefore is the first DUB enzyme exhibiting DNA-mediated activation at the replication fork, and is required for fork protection in BRCA1 deficient cells. We propose small molecule inhibitors against USP1 as a therapeutic option for BRCA1 deficient cancers. Citation Format: Kah Suan Lim, Heng Li, Emma A. Roberts, Emily F. Gaudiano, Connor Clairmont, Karthikeyan Ponnienselvan, Jessica C. Liu, Kalindi Parmar, Ning Zheng, Alan D9Andrea. USP1 is required for replication fork stability in BRCA1-deficient tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 333.
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small molecule inhibitors of USP1 target id1 degradation in leukemic cells
Molecular Cancer Therapeutics, 2013Co-Authors: Helena Mistry, Grace Hsieh, Sara J Buhrlage, Min Huang, Eunmi Park, Gregory D Cuny, Ilene Galinsky, Richard Stone, Nathanael S Gray, Alan D DandreaAbstract:Inhibitor of DNA-binding-1 (ID1) transcription factor is essential for the proliferation and progression of many cancer types including leukemia. However, the ID1 protein has not yet been therapeutically targeted in leukemia. ID1 is normally polyubiquitinated and degraded by the proteasome. Recently, it has been shown that USP1, a ubiquitin specific protease, deubiquitinates ID1 and rescues it from proteasome degradation. Inhibition of USP1 therefore offers a new avenue to target ID1 in cancer. Here, using a Ubiquitin-Rhodamine-based high throughput screening, we identified small molecule inhibitors of USP1 and investigated their therapeutic potential for leukemia. These inhibitors blocked the deubiquitinating enzyme activity of USP1 in vitro in a dose-dependent manner with an IC50 in the high nanomolar range. USP1 inhibitors promoted the degradation of ID1 and, concurrently, inhibited the growth of leukemic cell lines in a dose dependent manner. A known USP1 inhibitor, Pimozide, also promoted ID1 degradation and inhibited growth of leukemic cells. In addition, the growth of primary Acute Myeloid Leukemia (AML) patient-derived leukemic cells was inhibited by a USP1 inhibitor. Collectively, these results indicate that the novel small molecule inhibitors of USP1 promote ID1 degradation and are cytotoxic to leukemic cells. The identification of USP1 inhibitors therefore opens up a new approach for leukemia therapy.
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small molecule inhibitors of USP1 target id1 degradation in leukemic cells and cause cytotoxicity
Blood, 2013Co-Authors: Grace Hsieh, Sara J Buhrlage, Min Huang, Eunmi Park, Gregory D Cuny, Ilene Galinsky, Richard Stone, Nathanael S Gray, Kalindi Parmar, Alan D DandreaAbstract:ID1 (inhibitor of DNA-binding-1) is a member of the helix-loop-helix family of transcriptional regulatory proteins. The ID-family of proteins (ID1-ID4) inhibit the DNA binding of transcription factors which regulate cellular differentiation and proliferation. Accordingly, deregulation of ID proteins has been observed in many cancer types including leukemia. High levels of ID1 expression are found in primary acute myeloid leukemia (AML) samples and correlate with poor prognosis. ID1 is also identified as a common downstream target of the oncogenic tyrosine kinases, BCR-ABL, TEL-ABL and FLT3-ITD. In addition, Id1 has been shown to promote a myeloproliferative disease in mice, and knockdown of ID1 expression inhibits leukemic cell growth. Therefore, ID1 is an excellent candidate for targeted therapy in leukemia. However, suitable drugs to target ID1 have not been developed to date. ID1 is normally polyubiquitinated and degraded by the proteasome. Recently, it has been shown that USP1, a ubiquitin specific protease, deubiquitinates ID1 and rescues it from proteasome degradation. Inhibition of USP1 therefore offers a new avenue to target ID1 in cancer. Here, using a Ubiquitin-Rhodamine-based high throughput screen, we identified small molecule inhibitors of USP1 and investigated their therapeutic potential for leukemia. These inhibitors blocked the deubiquitinating enzyme activity of USP1 in vitro in a dose-dependent manner with an IC50 in the nanomolar range, and also targeted the enzyme activity of native USP1. To determine the cellular consequences of USP1 inhibition, we exposed leukemic cells to micromolar concentrations of the inhibitors and evaluated ID1 levels and survival. USP1 inhibitors promoted the degradation of ID1 and, concurrently, inhibited the growth (>90% inhibition in 24 hrs) of chronic myelogenous leukemia (CML) and AML cell lines with induction of apoptosis in a dose dependent manner. The EC50 of the inhibitors for the leukemic cell growth inhibition was approximately 1.07 μM ± 0.08 (95% Confidence Limits). Interestingly, exposure to low doses of USP1 inhibitor for 5 days in culture resulted in erythroid differentiation of K562 leukemic cells. A known USP1 inhibitor, Pimozide, also promoted ID1 degradation and inhibited growth of leukemic cells (>90% inhibition in 48 hrs), though at a higher drug concentrations as compared to the novel USP1 inhibitors. Importantly, the novel USP1 inhibitors promoted ID1 degradation and exhibited cytotoxicity (>90% death in 48 hrs) in primary AML patient-derived leukemic cells. Notably, siRNA-mediated knockdown of USP1 in K562 leukemic cells resulted in growth inhibition, increased apoptosis and cell cycle arrest. Collectively, our results demonstrate that the novel small molecule inhibitors of USP1 promote ID1 degradation and are cytotoxic to leukemic cells. The identification of USP1 inhibitors therefore opens up a new approach for leukemia therapy. Disclosures: No relevant conflicts of interest to declare.
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characterization of full length recombinant amsh usp9x and USP1 clinically relevant deubiquitinases involved in hematological malignancies
Blood, 2013Co-Authors: Nate Russell, Alan D Dandrea, Kalindi Parmar, Trevor Taylor, Bradley B Brasher, Francesco D MelandriAbstract:Attachment of polyubiquitin to substrate proteins generates important biological signaling cues that are inherent to the linkage type of the polyubiquitin chain. For example, K48-linked polyubiquitin chains result in proteasome-mediated degradation of proteins to which they are attached, whereas K63-linked polyubiquitin chains play roles in various intracellular signaling cascades. An important feature of protein ubiquitination is that it is reversible. Substrate-anchored chains may be edited or removed from proteins by highly specialized proteases called deubiquitinating enzymes (DUBs). There are approximately 90 DUBs identified in humans and many have been identified as potential druggable targets because of their involvement in hematological malignancies such as Fanconi Anemia, human follicular lymphomas and diffuse large B-cell lymphomas. DUB activity is regulated by a variety of cues including specificity for a protein substrate(s) to which polyubiquitin chains are conjugated; the presence of protein cofactor(s) that activate or inhibit DUB function; or preference for a specific polyubiquitin linkage type(s). Thus, understanding the mechanisms, regulation, and substrate preferences for deubiquitinases is of great interest, from both academic and clinical viewpoints. To help address these needs, we produced highly purified recombinant deubiquitinase enzymes to facilitate in vitro biochemical studies and drug-discovery efforts. Herein we report the initial characterization of the following, clinically-relevant enzymes: 1. AMSH is a JAMM-class metalloprotease that specifically cleaves K63-linked polyubiquitin chains. This DUB is activated by its partner STAM at the endosome, where its activity opposes ubiquitin-dependent sorting of receptors to lysosomes. AMSH plays important roles in cell growth, and IL-2, GM-CSF, and BMP (bone morphogenetic protein) signaling pathways. Our results demonstrate that recombinant AMSH has no activity against commonly used DUB substrates such as ubiquitin-AMC and ubiquitin-rhodamine. AMSH hydrolyzed K63-linked diubiquitin substrates (but not diubiquitin of other linkage types), and this activity was increased by an order of magnitude in the presence of recombinant STAM protein. 2. USP9x is an essential component of TGFβ/BMP signaling cascades. USP9x biology is likely to be complex, as over-expression of the DUB correlates with increased MCL1 protein—a driving force in both follicular- and diffuse large B-cell lymphomas. Conversely, decreased expression of USP9x cooperates with K-RAS mutations to accelerate aggressive pancreatic tumors in mice. This DUB was reported to hydrolyze K29- and K33-linked polyubiquitins chains, as well as numerous K48-linked polyubiquitinated substrates. The full-length recombinant USP9x is highly active against ubiquitin-AMC (kcat/Km = 1.1x106 M-1 s-1), and cleaves all polyubiquitin chain linkages other than linear- (“Met1-linked”) and K27-linked, demonstrating the potential for this deubiquitinase to act on multiple targets. 3. USP1 is a deubiquitinating enzyme of the C19 peptidase family and functions as a negative regulator of the Fanconi Anemia pathway. Reported substrates of USP1 include monoubiquitinated forms of FANCD2, PCNA and ID1. USP1 plays important roles in DNA damage responses and cancer-related processes, and inhibiting the function of this DUB sensitizes some cancer cells to chemotherapy. USP1 is nearly completely inactive in the absence of its activating partner, UAF1. We observed that recombinant USP1/UAF1 complex was able to efficiently cleave K6- and K63-linked diubiquitin chains, and hydrolyzed ubiquitin-AMC with great efficiency (kcat/Km = 1.3x106 M-1 s-1). Potent, small-molecule inhibitors of USP1 have been identified using in vitro assays, and data from ongoing studies to determine the potency of these inhibitors against USP1/UAF1 complex will be presented. In conclusion, we have investigated the in vitro substrate preferences and kinetic profiles of three deubiquitinases of clinical relevance. This data will be valuable in the design and analysis of assays used to identify small-molecule inhibitors of these highly specialized proteases. Disclosures: Russell: Boston Biochem Inc: Employment. Taylor: Boston Biochem Inc: Employment. Brasher: Boston Biochem Inc: Employment. Melandri: Boston Biochem Inc: Employment.
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the USP1 uaf1 complex promotes double strand break repair through homologous recombination
Molecular and Cellular Biology, 2011Co-Authors: Kailin Yang, Junko Murai, Donniphat Dejsuphong, Kouji Hirota, Shunichi Takeda, Alan D DandreaAbstract:Protein ubiquitination plays a key role in the regulation of a variety of DNA repair mechanisms. Protein ubiquitination is controlled by the coordinate activity of ubiquitin ligases and deubiquitinating enzymes (DUBs). The deubiquitinating enzyme USP1 regulates DNA repair and the Fanconi anemia pathway through its association with its WD40 binding partner, UAF1, and through its deubiquitination of two critical DNA repair proteins, FANCD2-Ub and PCNA-Ub. To investigate the function of USP1 and UAF1, we generated USP1−/−, UAF1−/−/−, and USP1−/− UAF1−/−/− chicken DT40 cell clones. These three clones showed similar sensitivities to chemical cross-linking agents, to a topoisomerase poison, camptothecin, and to an inhibitor of poly(ADP-ribose) polymerase (PARP), indicating that the USP1/UAF1 complex is a regulator of the cellular response to DNA damage. The hypersensitivity to both camptothecin and a PARP inhibitor suggests that the USP1/UAF1 complex promotes homologous recombination (HR)-mediated double-strand break (DSB) repair. To gain insight into the mechanism of the USP1/UAF1 complex in HR, we inactivated the nonhomologous end-joining (NHEJ) pathway in UAF1-deficient cells. Disruption of NHEJ in UAF1-deficient cells restored cellular resistance to camptothecin and the PARP inhibitor. Our results indicate that the USP1/UAF1 complex promotes HR, at least in part by suppressing NHEJ.
Zhihao Zhuang - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structure activity relationship studies of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against nonsmall cell lung cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit Jadhav, Zhihao ZhuangAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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abstract lb 11 discovery synthesis and structure activity relationship of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against non small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Abstract LB-11: Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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The WD40-Repeat Protein-Containing Deubiquitinase Complex: Catalysis, Regulation, and Potential for Therapeutic Intervention
Cell Biochemistry and Biophysics, 2013Co-Authors: Mark A. Villamil, Qin Liang, Zhihao ZhuangAbstract:Ubiquitination has emerged as an essential signaling mechanism in eukaryotes. Deubiquitinases (DUBs) counteract the activities of the ubiquitination machinery and provide another level of control in cellular ubiquitination. Not surprisingly, DUBs are subjected to stringent regulations. Besides regulation by the noncatalytic domains present in the DUB sequences, DUB-interacting proteins are increasingly realized as essential regulators for DUB activity and function. This review focuses on DUBs that are associated with WD40-repeat proteins. Many human ubiquitin-specific proteases (USPs) were found to interact with WD40-repeat proteins, but little is known as to how this interaction regulates the activity and function of USPs. In recent years, significant progress has been made in understanding a prototypical WD40-repeat protein-containing DUB complex that comprises USP1 and USP1-associated factor 1 (UAF1). It has been shown that UAF1 activates USP1 through a potential active-site modulation, and the complex formation between USP1 and UAF1 is regulated by serine phosphorylation. Recently, human USPs have been recognized as a promising target class for inhibitor discovery. Small molecule inhibitors targeting several human USPs have been reported. USP1 is involved in two major DNA damage response pathways, DNA translesion synthesis and the Fanconi anemia pathway. Inhibiting the USP1/UAF1 deubiquitinase complex represents a new strategy to potentiate cancer cells to DNA-crosslinking agents and to overcome resistance that has plagued clinical cancer chemotherapy. The progress in inhibitor discovery against USPs and the WD40-repeat protein-containing USP complex will be discussed.
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Serine Phosphorylation Is Critical for the Activation of Ubiquitin-Specific Protease 1 and Its Interaction with WD40-Repeat Protein UAF1
Biochemistry, 2012Co-Authors: Mark A. Villamil, Qin Liang, Junjun Chen, Yong Seok Choi, Zhihao ZhuangAbstract:Deubiquitinating enzymes (DUBs) are important for the normal function of a number of cellular processes, including transcriptional regulation, cell cycle control, and DNA damage response. The enzymatic activity of DUB is regulated by different mechanisms. DUBs in several different families are post-translationally modified by phosphorylation. Large-scale phosphoproteomic studies of human DUBs revealed that a majority of ubiquitin-specific proteases (USPs) are phosphorylated. USP1 is a prototypical DUB that requires a specific interaction with a WD40-repeat protein, UAF1, for its catalytic activity. In this study, we show that Ser313 phosphorylation in USP1 is required for its interaction with UAF1 and for the stimulation of USP1’s activity. In contrast, two other known USP1 serine phosphorylations (Ser42 and Ser67) are dispensable with respect to the activity of the USP1/UAF1 complex. An S313D phosphomimetic mutation in USP1 can substitute for Ser313 phosphorylation in promoting the formation of the USP1/...
Mark A. Villamil - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structure activity relationship studies of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against nonsmall cell lung cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit Jadhav, Zhihao ZhuangAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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abstract lb 11 discovery synthesis and structure activity relationship of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against non small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Abstract LB-11: Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Synthesis and Structure–Activity Relationship Studies of N-Benzyl-2-phenylpyrimidin-4-amine Derivatives as Potent USP1/UAF1 Deubiquitinase Inhibitors with Anticancer Activity against Nonsmall Cell Lung Cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit JadhavAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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a selective USP1 uaf1 inhibitor links deubiquitination to dna damage responses
Nature Chemical Biology, 2014Co-Authors: Qin Liang, Mark A. Villamil, Junjun Chen, Thomas S Dexheimer, Andrew S Rosenthal, Diane K Luci, Ping Zhang, Qiuting Zhang, Bifeng Yuan, Anton SimeonovAbstract:Deubiquitinases (DUBs) are peptidases that remove ubiquitin from post-translationally modified proteins. The identification of a selective small-molecule inhibitor of the USP1–UAF1 deubiquitination complex reveals a role for deubiquitination in regulating the DNA damage response.
Qin Liang - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structure activity relationship studies of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against nonsmall cell lung cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit Jadhav, Zhihao ZhuangAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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abstract lb 11 discovery synthesis and structure activity relationship of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against non small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Abstract LB-11: Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Synthesis and Structure–Activity Relationship Studies of N-Benzyl-2-phenylpyrimidin-4-amine Derivatives as Potent USP1/UAF1 Deubiquitinase Inhibitors with Anticancer Activity against Nonsmall Cell Lung Cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit JadhavAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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a selective USP1 uaf1 inhibitor links deubiquitination to dna damage responses
Nature Chemical Biology, 2014Co-Authors: Qin Liang, Mark A. Villamil, Junjun Chen, Thomas S Dexheimer, Andrew S Rosenthal, Diane K Luci, Ping Zhang, Qiuting Zhang, Bifeng Yuan, Anton SimeonovAbstract:Deubiquitinases (DUBs) are peptidases that remove ubiquitin from post-translationally modified proteins. The identification of a selective small-molecule inhibitor of the USP1–UAF1 deubiquitination complex reveals a role for deubiquitination in regulating the DNA damage response.
Thomas S Dexheimer - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structure activity relationship studies of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against nonsmall cell lung cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit Jadhav, Zhihao ZhuangAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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abstract lb 11 discovery synthesis and structure activity relationship of n benzyl 2 phenylpyrimidin 4 amine derivatives as potent USP1 uaf1 deubiquitinase inhibitors with anticancer activity against non small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Abstract LB-11: Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer
Cancer Research, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Zhihao Zhuang, Andrew S Rosenthal, Diane K Luci, Anton Simeonov, Ajit Jadhav, David J MaloneyAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Protein ubiquitination is a dynamic and reversible post-translational modification that has been linked to many essential cellular processes in eukaryotes. In addition, deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases, including cancer. For example, the deubiquitinating enzyme USP1 (ubiquitin-specific protease 1) in association with its WD40-repeat protein binding partner, UAF1 (USP1-associated factor 1), is a known regulator of DNA damage tolerance and repair and has been proposed as a promising target for anticancer therapy. To further evaluate the USP1/UAF1 complex as a therapeutic target, we conducted a quantitative high throughput screen of >400,000 compounds and subsequent medicinal chemistry optimization in pursuit of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. These efforts lead to the identification of ML323 and a series of N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibition and exhibit excellent selectivity over related proteases. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition in vitro and activity in non-small cell lung cancer cells, specifically increasing the level of ubiquitinated-PCNA and decreasing cell survival. Taken together, our results establish the druggability of the USP1/UAF1 deubiquitinase complex and its potential as molecular target for anticancer therapies. Citation Format: Thomas S. Dexheimer, Andrew S. Rosenthal, Diane Luci, Qin Liang, Mark A. Villamil, Ajit Jadhav, Anton Simeonov, Zhihao Zhuang, David J. Maloney. Discovery, synthesis, and structure-activity relationship of N-benzyl-2-phenylpyrimidin-4-amine derivatives as potent USP1/UAF1 deubiquitinase inhibitors with anticancer activity against non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-11. doi:10.1158/1538-7445.AM2014-LB-11
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Synthesis and Structure–Activity Relationship Studies of N-Benzyl-2-phenylpyrimidin-4-amine Derivatives as Potent USP1/UAF1 Deubiquitinase Inhibitors with Anticancer Activity against Nonsmall Cell Lung Cancer
Journal of Medicinal Chemistry, 2014Co-Authors: Thomas S Dexheimer, Mark A. Villamil, Qin Liang, Junjun Chen, Andrew S Rosenthal, Diane K Luci, Edward H Kerns, Anton Simeonov, Ajit JadhavAbstract:Deregulation of ubiquitin conjugation or deconjugation has been implicated in the pathogenesis of many human diseases including cancer. The deubiquitinating enzyme USP1 (ubiquitin-specific protease 1), in association with UAF1 (USP1-associated factor 1), is a known regulator of DNA damage response and has been shown as a promising anticancer target. To further evaluate USP1/UAF1 as a therapeutic target, we conducted a quantitative high throughput screen of >400000 compounds and subsequent medicinal chemistry optimization of small molecules that inhibit the deubiquitinating activity of USP1/UAF1. Ultimately, these efforts led to the identification of ML323 (70) and related N-benzyl-2-phenylpyrimidin-4-amine derivatives, which possess nanomolar USP1/UAF1 inhibitory potency. Moreover, we demonstrate a strong correlation between compound IC50 values for USP1/UAF1 inhibition and activity in nonsmall cell lung cancer cells, specifically increased monoubiquitinated PCNA (Ub-PCNA) levels and decreased cell surviv...
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a selective USP1 uaf1 inhibitor links deubiquitination to dna damage responses
Nature Chemical Biology, 2014Co-Authors: Qin Liang, Mark A. Villamil, Junjun Chen, Thomas S Dexheimer, Andrew S Rosenthal, Diane K Luci, Ping Zhang, Qiuting Zhang, Bifeng Yuan, Anton SimeonovAbstract:Deubiquitinases (DUBs) are peptidases that remove ubiquitin from post-translationally modified proteins. The identification of a selective small-molecule inhibitor of the USP1–UAF1 deubiquitination complex reveals a role for deubiquitination in regulating the DNA damage response.
