1
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Portugal J. Mithramycin and its analogs: Molecular features and antitumor action. Pharmacol Ther 2024; 260:108672. [PMID: 38838821 DOI: 10.1016/j.pharmthera.2024.108672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/09/2024] [Accepted: 06/01/2024] [Indexed: 06/07/2024]
Abstract
The antitumor antibiotic mithramycin A (MTA) binds to G/C-rich DNA sequences in the presence of dications. MTA inhibits transcription regulated by the Sp1 transcription factor, often enhanced during tumor development. It shows antitumor activity, but its clinical use was discontinued due to toxic side effects. However, recent observations have led to its use being reconsidered. The MTA biosynthetic pathways have been modified to produce mithramycin analogs (mithralogs) that encompass lower toxicity and improved pharmacological activity. Some mithralogs reduce gene expression in human ovarian and prostate tumors, among other types of cancer. They down-regulate gene expression in various cellular processes, including Sp1-responsive genes that control tumor development. Moreover, MTA and several mithralogs, such as EC-8042 (DIG-MSK) and EC-8105, effectively treat Ewing sarcoma by inhibiting transcription controlled by the oncogenic EWS-FLI1 transcription factor.
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Affiliation(s)
- José Portugal
- Instituto de Diagnóstico Ambiental y Estudios del Agua, CSIC, E-08034 Barcelona, Spain.
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2
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Zhu C, Wang Y, Li Y, Wang T, Ye F, Su W, Chen T, Zhang C, Xiong L. Discovery of neuroprotective Agents: Potent, brain Penetrating, lipoic acid derivatives for the potential treatment of ischemic stroke by regulating oxidative stress and inflammation - a Preliminary study. Bioorg Chem 2024; 147:107339. [PMID: 38643566 DOI: 10.1016/j.bioorg.2024.107339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/02/2024] [Accepted: 04/04/2024] [Indexed: 04/23/2024]
Abstract
Stroke poses a serious risk to the physical and mental health of patients. Endogenous compounds are widely used to treat ischemic stroke. Lipoic acid, a naturally occurring (R)-5-(1,2-dithiolan-3-yl)pentanoic acid, has therapeutic potential for the treatment of ischemic stroke. However, the direct application of lipoic acid is limited by its relatively low efficacy and instability. Therefore, there is a need to modify the structure of lipoic acid to improve its pharmaceutical capabilities. Currently, 37 lipoic acid derivatives have been synthesized, and compound AA-9 demonstrated optimal therapeutic potential in an in vitro model of induced oxidative damage using tert-butyl hydroperoxide (t-BHP). In addition, in vitro experiments have shown that compound AA-9 has an excellent safety profile. Subsequently, the therapeutic effect of AA-9 was significant in the rat MCAO ischemic stroke model, which may be attributed to the antioxidant and anti-inflammatory effects of compound AA-9 by activating PGC-1α and inhibiting NLRP3. Notably, compound AA-9 exhibited higher stability and better bioavailability properties than ALA in plasma stability and pharmacokinetic properties. In conclusion, AA-9 may be a promising neuroprotective agent for the treatment of ischemic stroke and warrants further investigation.
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Affiliation(s)
- Chenchen Zhu
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Yun Wang
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Yi Li
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Tingfang Wang
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Fei Ye
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Wei Su
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China
| | - Ting Chen
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China.
| | - Chuan Zhang
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China.
| | - Liyan Xiong
- Shanghai Baoshan Luodian hospital, School of Medicine, Shanghai University, Shanghai 201908, China.
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3
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Legrand AJ, Choul-li S, Villeret V, Aumercier M. Poly(ADP-ribose) Polyremase-1 (PARP-1) Inhibition: A Promising Therapeutic Strategy for ETS-Expressing Tumours. Int J Mol Sci 2023; 24:13454. [PMID: 37686260 PMCID: PMC10487777 DOI: 10.3390/ijms241713454] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/17/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
ETS transcription factors are a highly conserved family of proteins involved in the progression of many cancers, such as breast and prostate carcinomas, Ewing's sarcoma, and leukaemias. This significant involvement can be explained by their roles at all stages of carcinogenesis progression. Generally, their expression in tumours is associated with a poor prognosis and an aggressive phenotype. Until now, no efficient therapeutic strategy had emerged to specifically target ETS-expressing tumours. Nevertheless, there is evidence that pharmacological inhibition of poly(ADP-ribose) polymerase-1 (PARP-1), a key DNA repair enzyme, specifically sensitises ETS-expressing cancer cells to DNA damage and limits tumour progression by leading some of the cancer cells to death. These effects result from a strong interplay between ETS transcription factors and the PARP-1 enzyme. This review summarises the existing knowledge of this molecular interaction and discusses the promising therapeutic applications.
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Affiliation(s)
- Arnaud J. Legrand
- CNRS, EMR9002 Integrative Structural Biology, F-59000 Lille, France; (A.J.L.); (V.V.)
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE-Risk Factors and Molecular Deter-minants of Aging-Related Diseases, F-59000 Lille, France
| | - Souhaila Choul-li
- Département de Biologie, Faculté des Sciences, Université Chouaib Doukkali, BP-20, El Jadida 24000, Morocco;
| | - Vincent Villeret
- CNRS, EMR9002 Integrative Structural Biology, F-59000 Lille, France; (A.J.L.); (V.V.)
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE-Risk Factors and Molecular Deter-minants of Aging-Related Diseases, F-59000 Lille, France
| | - Marc Aumercier
- CNRS, EMR9002 Integrative Structural Biology, F-59000 Lille, France; (A.J.L.); (V.V.)
- Univ. Lille, Inserm, CHU Lille, Institut Pasteur de Lille, U1167-RID-AGE-Risk Factors and Molecular Deter-minants of Aging-Related Diseases, F-59000 Lille, France
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4
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Gong H, Xue B, Ru J, Pei G, Li Y. Targeted Therapy for EWS-FLI1 in Ewing Sarcoma. Cancers (Basel) 2023; 15:4035. [PMID: 37627063 PMCID: PMC10452796 DOI: 10.3390/cancers15164035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 08/05/2023] [Accepted: 08/06/2023] [Indexed: 08/27/2023] Open
Abstract
Ewing sarcoma (EwS) is a rare and predominantly pediatric malignancy of bone and soft tissue in children and adolescents. Although international collaborations have greatly improved the prognosis of most EwS, the occurrence of macrometastases or relapse remains challenging. The prototypic oncogene EWS-FLI1 acts as an aberrant transcription factor that drives the cellular transformation of EwS. In addition to its involvement in RNA splicing and the DNA damage response, this chimeric protein directly binds to GGAA repeats, thereby modifying the transcriptional profile of EwS. Direct pharmacological targeting of EWS-FLI1 is difficult because of its intrinsically disordered structure. However, targeting the EWS-FLI1 protein complex or downstream pathways provides additional therapeutic options. This review describes the EWS-FLI1 protein partners and downstream pathways, as well as the related target therapies for the treatment of EwS.
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Affiliation(s)
- Helong Gong
- Department of Orthopaedic Surgery, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang 110004, China;
| | - Busheng Xue
- Department of Hematology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, China;
| | - Jinlong Ru
- Institute of Virology, Helmholtz Centre Munich, German Research Centre for Environmental Health, 85764 Neuherberg, Germany;
| | - Guoqing Pei
- Department of Orthopedics, Xijing Hospital, Air Force Medical University, Xi’an 710032, China;
| | - Yan Li
- Department of Orthopaedic Surgery, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang 110004, China;
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Liao S, Yuk N, Kim YJ, Xu H, Li X, Wang L, Liu Y, Jung HJ. Novel terpestacin derivatives with l-amino acid residue as anticancer agents against U87MG-derived glioblastoma stem cells. Bioorg Chem 2023; 132:106392. [PMID: 36709667 DOI: 10.1016/j.bioorg.2023.106392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 01/25/2023]
Abstract
Based on the natural product terpestacin, seventeen derivatives (1-17) with various l-amino acid side chains were designed and synthesized. Their anticancer activities against U87MG-derived glioblastoma stem cells (GSCs) were evaluated, and compounds 5, 11, 13 and 15 showed strong abilities to inhibit the proliferation (IC50 = 2.8-6.9 μM) and tumorsphere formation of GSCs. Besides, compounds 13 and 15 could effectively induce apoptosis and significantly inhibit the invasion of GSCs (95 and 97 % inhibition, respectively, at 2.5 μM). The levels of CD133 marker in GSCs also decreased in dose-dependent manners after the treatment of these active compounds. Compared to terpestacin and the positive control A1938, our derivatives showed stronger activities and compounds 13 and 15 are promising candidates for further development as anticancer agents by targeting GSCs.
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Affiliation(s)
- Shengrong Liao
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Research Center for Marine Microbes, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Nayeong Yuk
- Department of Pharmaceutical Engineering and Biotechnology, Genome-Based BioIT Convergence Institute, Sun Moon University, Asan 31460, Korea
| | - Yu Jin Kim
- Department of Pharmaceutical Engineering and Biotechnology, Genome-Based BioIT Convergence Institute, Sun Moon University, Asan 31460, Korea
| | - Huayan Xu
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Xiaolin Li
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Research Center for Marine Microbes, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ling Wang
- Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, Joint International Research Laboratory of Synthetic Biology and Medicine, Guangdong Provincial Engineering and Technology Research Center of Biopharmaceuticals, School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yonghong Liu
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Research Center for Marine Microbes, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Hye Jin Jung
- Department of Pharmaceutical Engineering and Biotechnology, Genome-Based BioIT Convergence Institute, Sun Moon University, Asan 31460, Korea.
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Wang Y, Huang Z, Sun M, Huang W, Xia L. ETS transcription factors: Multifaceted players from cancer progression to tumor immunity. Biochim Biophys Acta Rev Cancer 2023; 1878:188872. [PMID: 36841365 DOI: 10.1016/j.bbcan.2023.188872] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/18/2023] [Accepted: 01/28/2023] [Indexed: 02/26/2023]
Abstract
The E26 transformation specific (ETS) family comprises 28 transcription factors, the majority of which are involved in tumor initiation and development. Serving as a group of functionally heterogeneous gene regulators, ETS factors possess a structurally conserved DNA-binding domain. As one of the most prominent families of transcription factors that control diverse cellular functions, ETS activation is modulated by multiple intracellular signaling pathways and post-translational modifications. Disturbances in ETS activity often lead to abnormal changes in oncogenicity, including cancer cell survival, growth, proliferation, metastasis, genetic instability, cell metabolism, and tumor immunity. This review systematically addresses the basics and advances in studying ETS factors, from their tumor relevance to clinical translational utility, with a particular focus on elucidating the role of ETS family in tumor immunity, aiming to decipher the vital role and clinical potential of regulation of ETS factors in the cancer field.
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Affiliation(s)
- Yufei Wang
- Department of Gastroenterology, Institute of Liver and Gastrointestinal Diseases, Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China
| | - Zhao Huang
- Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Clinical Medicine Research Center for Hepatic Surgery of Hubei Province, Key Laboratory of Organ Transplantation, Ministry of Education and Ministry of Public Health, Wuhan, Hubei 430030, China
| | - Mengyu Sun
- Department of Gastroenterology, Institute of Liver and Gastrointestinal Diseases, Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China
| | - Wenjie Huang
- Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Clinical Medicine Research Center for Hepatic Surgery of Hubei Province, Key Laboratory of Organ Transplantation, Ministry of Education and Ministry of Public Health, Wuhan, Hubei 430030, China.
| | - Limin Xia
- Department of Gastroenterology, Institute of Liver and Gastrointestinal Diseases, Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China.
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7
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Bhosale SS, Mandal A, Hou C, McCorkle JR, Schweer D, Hill KS, Subramanian V, Kolesar JM, Tsodikov OV, Rohr J. Mithplatins: Mithramycin SA-Pt(II) Complex Conjugates for the Treatment of Platinum-Resistant Ovarian Cancers. ChemMedChem 2023; 18:e202200368. [PMID: 36342449 PMCID: PMC9899322 DOI: 10.1002/cmdc.202200368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/04/2022] [Indexed: 11/09/2022]
Abstract
DNA coordinating platinum (Pt) containing compounds cisplatin and carboplatin have been used for the treatment of ovarian cancer therapy for four decades. However, recurrent Pt-resistant cancers are a major cause of mortality. To combat Pt-resistant ovarian cancers, we designed and synthesized a conjugate of an anticancer drug mithramycin with a reactive Pt(II) bearing moiety, which we termed mithplatin. The conjugates displayed both the Mg2+ -dependent noncovalent DNA binding characteristic of mithramycin and the covalent crosslinking to DNA of the Pt. The conjugate was three times as potent as cisplatin against ovarian cancer cells. The DNA lesions caused by the conjugate led to the generation of DNA double-strand breaks, as also observed with cisplatin. Nevertheless, the conjugate was highly active against both Pt-sensitive and Pt-resistant ovarian cancer cells. This study paves the way to developing mithplatins to combat Pt-resistant ovarian cancers.
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Affiliation(s)
- Suhas S Bhosale
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Abhisek Mandal
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Caixia Hou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - J Robert McCorkle
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - David Schweer
- Division of Gynecologic Oncology, College of Medicine, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - Kristen S Hill
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
| | - Vivekanandan Subramanian
- University of Kentucky PharmNMR Center, College of Pharmacy, University of Kentucky, Lexington, KY, 40536-0596, USA
| | - Jill M Kolesar
- Markey Cancer Center, University of Kentucky, 760 S. Rose Street, Lexington, KY, 40536, USA
- Division of Gynecologic Oncology, College of Medicine, 760 S. Rose Street, Lexington, KY, 40536, USA
- Department of Pharmacy Practice and Science, College of Pharmacy, University of Kentucky, 760 Press Avenue, Lexington, KY, 40536, USA
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone Street, Lexington, KY, 40536, USA
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Insight into mithramycin disruption of ETS transcription leads to improved understanding of more selective analogs. Structure 2021; 29:401-403. [PMID: 33961789 DOI: 10.1016/j.str.2021.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fusion products with the ETS family of transcription factors play critical roles in the etiology of several cancers. In this issue of Structure, Hou et al. (2020) provide insight into allosteric mechanisms by which mithramycin and its analogs perturb protein-DNA interactions in higher-order complexes at a DNA enhancer site.
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Interleukin-10 suppression enhances T-cell antitumor immunity and responses to checkpoint blockade in chronic lymphocytic leukemia. Leukemia 2021; 35:3188-3200. [PMID: 33731852 PMCID: PMC8446094 DOI: 10.1038/s41375-021-01217-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 02/15/2021] [Accepted: 03/04/2021] [Indexed: 02/07/2023]
Abstract
T-cell dysfunction is a hallmark of B-cell Chronic Lymphocytic Leukemia (CLL), where CLL cells downregulate T-cell responses through regulatory molecules including programmed death ligand-1 (PD-L1) and Interleukin-10 (IL-10). Immune checkpoint blockade (ICB) aims to restore T-cell function by preventing the ligation of inhibitory receptors like PD-1. However, most CLL patients do not respond well to this therapy. Thus, we investigated whether IL-10 suppression could enhance antitumor T-cell activity and responses to ICB. Since CLL IL-10 expression depends on Sp1, we utilized a novel, better tolerated analogue of the Sp1 inhibitor mithramycin (MTMox32E) to suppress CLL IL-10. MTMox32E treatment inhibited mouse and human CLL IL-10 production and maintained T-cell effector function in vitro. In the Eμ-Tcl1 mouse model, treatment reduced plasma IL-10 and CLL burden and increased CD8+ T-cell proliferation, effector and memory cell prevalence, and interferon-γ production. When combined with ICB, suppression of IL-10 improved responses to anti-PD-L1 as shown by a 4.5-fold decrease in CLL cell burden compared to anti-PD-L1 alone. Combination therapy also produced more interferon-γ+, cytotoxic effector KLRG1+, and memory CD8+ T-cells, and fewer exhausted T-cells. Since current therapies for CLL do not target IL-10, this provides a novel strategy to improve immunotherapies.
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Schweer D, McCorkle JR, Rohr J, Tsodikov OV, Ueland F, Kolesar J. Mithramycin and Analogs for Overcoming Cisplatin Resistance in Ovarian Cancer. Biomedicines 2021; 9:70. [PMID: 33445667 PMCID: PMC7828137 DOI: 10.3390/biomedicines9010070] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/05/2021] [Accepted: 01/07/2021] [Indexed: 12/12/2022] Open
Abstract
Ovarian cancer is a highly deadly malignancy in which recurrence is considered incurable. Resistance to platinum-based chemotherapy bodes a particularly abysmal prognosis, underscoring the need for novel therapeutic agents and strategies. The use of mithramycin, an antineoplastic antibiotic, has been previously limited by its narrow therapeutic window. Recent advances in semisynthetic methods have led to mithramycin analogs with improved pharmacological profiles. Mithramycin inhibits the activity of the transcription factor Sp1, which is closely linked with ovarian tumorigenesis and platinum-resistance. This article summarizes recent clinical developments related to mithramycin and postulates a role for the use of mithramycin, or its analog, in the treatment of platinum-resistant ovarian cancer.
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Affiliation(s)
- David Schweer
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology Lexington, University of Kentucky Markey Cancer Center, Lexington, KY 40536, USA; (D.S.); (F.U.)
| | - J. Robert McCorkle
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (J.R.M.); (J.R.); (O.V.T.)
| | - Jurgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (J.R.M.); (J.R.); (O.V.T.)
| | - Oleg V. Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA; (J.R.M.); (J.R.); (O.V.T.)
| | - Frederick Ueland
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology Lexington, University of Kentucky Markey Cancer Center, Lexington, KY 40536, USA; (D.S.); (F.U.)
| | - Jill Kolesar
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology Lexington, University of Kentucky Markey Cancer Center, Lexington, KY 40536, USA; (D.S.); (F.U.)
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11
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Mithramycin A Radiosensitizes EWS:Fli1 + Ewing Sarcoma Cells by Inhibiting Double Strand Break Repair. Int J Radiat Oncol Biol Phys 2020; 109:1454-1471. [PMID: 33373655 DOI: 10.1016/j.ijrobp.2020.12.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 11/17/2020] [Accepted: 12/08/2020] [Indexed: 02/03/2023]
Abstract
PURPOSE The oncogenic EWS:Fli1 fusion protein is a key transcriptional mediator of Ewing sarcoma initiation, progression, and therapeutic resistance. Mithramycin A (MithA) is a potent and specific inhibitor of transcription mediated by the EWS:Fli1. We tested the hypothesis that pretreatment with MithA could selectively radiosensitize EWS:Fli1+ tumor cells by altering the transcriptional response to radiation injury. METHODS AND MATERIALS A panel of 4 EWS:Fli1+ and 3 EWS:Fli1- Ewing sarcoma cell lines and 1 nontumor cell line were subjected to MithA dose-response viability assays to determine the relative potency of MithA in cells possessing or lacking the EWS:Fli1 fusion. Radiosensitization by MithA was evaluated by clonogenic survival assays in vitro and in a murine xenograft model. DNA damage was evaluated by comet assay and γ-H2Ax flow cytometry. Immunoblotting, flow cytometry, and reverse-transcription, polymerase chain reaction were used to evaluate DNA damage-induced signaling and repair processes and apoptosis. RESULTS We found that MithA alone could potently and selectively inhibit the growth of EWS:Fli1+ tumor cells, but not cells lacking this fusion. Pretreatment with MithA for 24 hours before irradiation significantly reduced clonogenic survival in vitro and delayed tumor regrowth in vivo, prolonging survival of EWS:Fli1+ tumor-bearing mice. Although MithA did not increase the level of DNA double-strand breaks, mechanistic studies revealed that MithA pretreatment selectively inhibited DNA double-strand break repair through downregulation of EWS:Fli1-mediated transcription, leading to tumor cell death by apoptosis. CONCLUSIONS Our data indicate that MithA is an effective radiosensitizer of EWS:Fli1+ tumors and may achieve better local control at lower doses of radiation.
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Hou C, Mandal A, Rohr J, Tsodikov OV. Allosteric interference in oncogenic FLI1 and ERG transactions by mithramycins. Structure 2020; 29:404-412.e4. [PMID: 33275876 DOI: 10.1016/j.str.2020.11.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/24/2020] [Accepted: 11/12/2020] [Indexed: 12/20/2022]
Abstract
ETS family transcription factors of ERG and FLI1 play a key role in oncogenesis of prostate cancer and Ewing sarcoma by binding regulatory DNA sites and interfering with function of other factors. Mithramycin (MTM) is an anti-cancer, DNA binding natural product that functions as a potent antagonist of ERG and FLI1 by an unknown mechanism. We present a series of crystal structures of the DNA binding domain (DBD) of ERG/FLI1 culminating in a structure of a high-order complex of the ERG/FLI1 DBD, transcription factor Runx2, core-binding factor beta (Cbfβ), and MTM on a DNA enhancer site, along with supporting DNA binding studies using MTM and its analogues. Taken together, these data provide insight into allosteric mechanisms underlying ERG and FLI1 transactions and their disruption by MTM analogues.
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Affiliation(s)
- Caixia Hou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | - Abhisek Mandal
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA.
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13
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Liu Y, Eckenrode JM, Zhang Y, Zhang J, Hayden RC, Kyomuhangi A, Ponomareva LV, Cui Z, Rohr J, Tsodikov OV, Van Lanen SG, Shaaban KA, Leggas M, Thorson JS. Mithramycin 2'-Oximes with Improved Selectivity, Pharmacokinetics, and Ewing Sarcoma Antitumor Efficacy. J Med Chem 2020; 63:14067-14086. [PMID: 33191745 DOI: 10.1021/acs.jmedchem.0c01526] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Mithramycin A (MTM) inhibits the oncogenic transcription factor EWS-FLI1 in Ewing sarcoma, but poor pharmacokinetics (PK) and toxicity limit its clinical use. To address this limitation, we report an efficient MTM 2'-oxime (MTMox) conjugation strategy for rapid MTM diversification. Comparative cytotoxicity assays of 41 MTMox analogues using E-twenty-six (ETS) fusion-dependent and ETS fusion-independent cancer cell lines revealed improved ETS fusion-independent/dependent selectivity indices for select 2'-conjugated analogues as compared to MTM. Luciferase-based reporter assays demonstrated target engagement at low nM concentrations, and molecular assays revealed that analogues inhibit the transcriptional activity of EWS-FLI1. These in vitro screens identified MTMox32E (a Phe-Trp dipeptide-based 2'-conjugate) for in vivo testing. Relative to MTM, MTMox32E displayed an 11-fold increase in plasma exposure and improved efficacy in an Ewing sarcoma xenograft. Importantly, these studies are the first to point to simple C3 aliphatic side-chain modification of MTM as an effective strategy to improve PK.
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Affiliation(s)
- Yang Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Joseph M Eckenrode
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Yinan Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Jianjun Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Reiya C Hayden
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Annet Kyomuhangi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Larissa V Ponomareva
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Zheng Cui
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Steven G Van Lanen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Khaled A Shaaban
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Markos Leggas
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Jon S Thorson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States
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14
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Discrimination between G/C Binding Sites by Olivomycin A Is Determined by Kinetics of the Drug-DNA Interaction. Int J Mol Sci 2020; 21:ijms21155299. [PMID: 32722584 PMCID: PMC7432603 DOI: 10.3390/ijms21155299] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/20/2020] [Accepted: 07/23/2020] [Indexed: 12/25/2022] Open
Abstract
Olivomycin A (OA) exerts its cytotoxic potency due to binding to the minor groove of the G/C-rich DNA and interfering with replication and transcription. Screening of the complete set of tetranucleotide G/C sites by electrophoretic mobility gel shift assay (EMSA) revealed that the sites containing central GC or GG dinucleotides were able to bind OA, whereas the sites with the central CG dinucleotide were not. However, studies of equilibrium OA binding in solution by fluorescence, circular dichroism and isothermal titration calorimetry failed to confirm the sequence preference of OA, indicating instead a similar type of complex and comparable affinity of OA to all G/C binding sites. This discrepancy was resolved by kinetics analysis of the drug–DNA interaction: the dissociation rate significantly differed between SGCS, SGGS and SCGS sites (S stands for G or C), thereby explaining the disintegration of the complexes during EMSA. The functional relevance of the revealed differential kinetics of OA–DNA interaction was demonstrated in an in vitro transcription assay. These findings emphasize the crucial role of kinetics in the mechanism of OA action and provide an important approach to the screening of new drug candidates.
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15
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Kormanec J, Novakova R, Csolleiova D, Feckova L, Rezuchova B, Sevcikova B, Homerova D. The antitumor antibiotic mithramycin: new advanced approaches in modification and production. Appl Microbiol Biotechnol 2020; 104:7701-7721. [DOI: 10.1007/s00253-020-10782-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/30/2020] [Accepted: 07/07/2020] [Indexed: 12/15/2022]
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16
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Herrera-González I, Sánchez-Fernández EM, Sau A, Nativi C, García Fernández JM, Galán MC, Ortiz Mellet C. Stereoselective Synthesis of Iminosugar 2-Deoxy(thio)glycosides from Bicyclic Iminoglycal Carbamates Promoted by Cerium(IV) Ammonium Nitrate and Cooperative Brønsted Acid-Type Organocatalysis. J Org Chem 2020; 85:5038-5047. [PMID: 32159355 DOI: 10.1021/acs.joc.0c00324] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The first examples of iminosugar-type 2-deoxy(thio)glycoside mimetics are reported. The key step is the activation of a bicyclic iminoglycal carbamate to generate a highly reactive acyliminium cation. Cerium(IV) ammonium nitrate efficiently promoted the formation of 2-deoxy S-glycosides in the presence of thiols, probably by in situ generation of catalytic HNO3, with complete α-stereoselectivity. Cooperative phosphoric acid/Schreiner's thiourea organocatalysis proved better suited for generating 2-deoxy O-glycosides, significantly broadening the scope of the approach.
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Affiliation(s)
- Irene Herrera-González
- Deptartment of Química Orgánica, Facultad de Química, Universidad de Sevilla, C/ Profesor García González 1, E-41012 Sevilla, Spain
| | - Elena M Sánchez-Fernández
- Deptartment of Química Orgánica, Facultad de Química, Universidad de Sevilla, C/ Profesor García González 1, E-41012 Sevilla, Spain
| | - Abhijit Sau
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K
| | - Cristina Nativi
- Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia, 13, 50019 Sesto Fiorentino, Florence, Italy
| | - José M García Fernández
- Instituto de Investigaciones Químicas (IIQ), CSIC-Universidad de Sevilla, Avda. Américo Vespucio 49, E-41092 Sevilla, Spain
| | - M Carmen Galán
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K
| | - Carmen Ortiz Mellet
- Deptartment of Química Orgánica, Facultad de Química, Universidad de Sevilla, C/ Profesor García González 1, E-41012 Sevilla, Spain
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17
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Wheeler R, Yu X, Hou C, Mitra P, Chen JM, Herkules F, Ivanov DN, Tsodikov OV, Rohr J. Discovery of a Cryptic Intermediate in Late Steps of Mithramycin Biosynthesis. Angew Chem Int Ed Engl 2019; 59:826-832. [PMID: 31702856 DOI: 10.1002/anie.201910241] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/14/2019] [Indexed: 12/23/2022]
Abstract
MtmOIV and MtmW catalyze the final two reactions in the mithramycin (MTM) biosynthetic pathway, the Baeyer-Villiger opening of the fourth ring of premithramycin B (PMB), creating the C3 pentyl side chain, strictly followed by reduction of the distal keto group on the new side chain. Unexpectedly this results in a C2 stereoisomer of mithramycin, iso-mithramycin (iso-MTM). Iso-MTM undergoes a non-enzymatic isomerization to MTM catalyzed by Mg2+ ions. Crystal structures of MtmW and its complexes with co-substrate NADPH and PEG, suggest a catalytic mechanism of MtmW. The structures also show that a tetrameric assembly of this enzyme strikingly resembles the ring-shaped β subunit of a vertebrate ion channel. We show that MtmW and MtmOIV form a complex in the presence of PMB and NADPH, presumably to hand over the unstable MtmOIV product to MtmW, yielding iso-MTM, as a potential self-resistance mechanism against MTM toxicity.
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Affiliation(s)
- Ryan Wheeler
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Xia Yu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA.,Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan, 410013, P. R. China
| | - Caixia Hou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Prithiba Mitra
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Jhong-Min Chen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Frank Herkules
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, 78229, USA
| | - Dmitri N Ivanov
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, 78229, USA
| | - Oleg V Tsodikov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY, 40536-0596, USA
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18
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Wheeler R, Yu X, Hou C, Mitra P, Chen J, Herkules F, Ivanov DN, Tsodikov OV, Rohr J. Discovery of a Cryptic Intermediate in Late Steps of Mithramycin Biosynthesis. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Ryan Wheeler
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
| | - Xia Yu
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
- Xiangya School of Pharmaceutical SciencesCentral South University Changsha Hunan 410013 P. R. China
| | - Caixia Hou
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
| | - Prithiba Mitra
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
| | - Jhong‐Min Chen
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
| | - Frank Herkules
- Department of BiochemistryUniversity of Texas Health Science Center San Antonio TX 78229 USA
| | - Dmitri N. Ivanov
- Department of BiochemistryUniversity of Texas Health Science Center San Antonio TX 78229 USA
| | - Oleg V. Tsodikov
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
| | - Jürgen Rohr
- Department of Pharmaceutical SciencesCollege of PharmacyUniversity of Kentucky 789 South Limestone Street Lexington KY 40536-0596 USA
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19
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Eckenrode JM, Mitra P, Rohr J, Leggas M. Bioanalytical method for quantitative determination of mithramycin analogs in mouse plasma by HPLC-QTOF. Biomed Chromatogr 2019; 33:e4544. [PMID: 30927450 DOI: 10.1002/bmc.4544] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/19/2019] [Accepted: 03/26/2019] [Indexed: 11/06/2022]
Abstract
Mithramycin (MTM) has potent anticancer activity, but severe toxicities restrict its clinical use. Semi-synthetic approaches have yielded novel MTM analogs with potentially lower toxicity and similar efficacy. In an effort to transition these analogs into in vivo models, a bioanalytical method was developed for their quantification in mouse plasma. Here we present the validation of the method for the quantitation of mithramycin SA-tryptophan (MTMSA-Trp) as well as the applicability of the methodology for assaying additional analogs, including MTM, mithramycin SK (MTMSK) and mithramycin SA-phenylalanine (MTMSA-Phe) with run times of 6 min. Assay linearity ranged from 5 to 100 ng/mL. Accuracies of calibration standards and quality control samples were within 15% of nominal with precision variability of <20%. MTMSA-Trp was stable for 30 days at -80°C and for at least three freeze-thaw cycles. Methanol (-80°C) extraction afforded 92% of MTMSA-Trp from plasma. Calibration curves for MTM and analogs were also linear from ≤5 to 100 ng/mL. This versatile method was used to quantitate MTM analogs in plasma samples collected during preclinical pharmacokinetic studies.
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Affiliation(s)
- Joseph M Eckenrode
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, USA
| | - Prithiba Mitra
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, USA
| | - Jürgen Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Markos Leggas
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY, USA.,Markey Cancer Center, University of Kentucky, Lexington, KY, USA.,Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, KY, USA
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20
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Hou C, Rohr J, Parkin S, Tsodikov OV. How mithramycin stereochemistry dictates its structure and DNA binding function. MEDCHEMCOMM 2019; 10:735-741. [PMID: 31191864 DOI: 10.1039/c9md00100j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 03/28/2019] [Indexed: 12/16/2022]
Abstract
An aureolic acid natural product mithramycin (MTM) has been known for its potent antineoplastic properties. MTM inhibits cell growth by binding in the minor groove of double-stranded DNA as a dimer, in which the two molecules of MTM are coordinated to each other through a divalent metal ion. A crystal structure of an MTM analogue, MTM SA-Phe, in the active metal ion-coordinated dimeric form demonstrates how the stereochemical features of MTM define the helicity of the dimeric scaffold for its binding to a right-handed DNA double helix. We also show crystallographically and biochemically that MTM, but not MTM SA-Phe, can be inactivated by boric acid through formation of a large macrocyclic species, in which two molecules of MTM are crosslinked to each other through 3-side chain-boron-sugar intermolecular bonds. We discuss these structural and biochemical properties in the context of MTM biosynthesis and the design of MTM analogues as anticancer therapeutics.
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Affiliation(s)
- Caixia Hou
- University of Kentucky , Department of Pharmaceutical Sciences , College of Pharmacy , Lexington , KY 40536-0596 , USA . ;
| | - Jürgen Rohr
- University of Kentucky , Department of Pharmaceutical Sciences , College of Pharmacy , Lexington , KY 40536-0596 , USA . ;
| | - Sean Parkin
- University of Kentucky , Department of Chemistry , Lexington , KY 40506-0055 , USA .
| | - Oleg V Tsodikov
- University of Kentucky , Department of Pharmaceutical Sciences , College of Pharmacy , Lexington , KY 40536-0596 , USA . ;
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