1
|
Ketcham JM, Harwood SJ, Aranda R, Aloiau AN, Bobek BM, Briere DM, Burns AC, Caddell Haatveit K, Calinisan A, Clarine J, Elliott A, Engstrom LD, Gunn RJ, Ivetac A, Jones B, Kuehler J, Lawson JD, Nguyen N, Parker C, Pearson KE, Rahbaek L, Saechao B, Wang X, Waters A, Waters L, Watkins AH, Olson P, Smith CR, Christensen JG, Marx MA. Discovery of Pyridopyrimidinones that Selectively Inhibit the H1047R PI3Kα Mutant Protein. J Med Chem 2024; 67:4936-4949. [PMID: 38477582 PMCID: PMC10983000 DOI: 10.1021/acs.jmedchem.4c00078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/20/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024]
Abstract
The H1047R mutation of PIK3CA is highly prevalent in breast cancers and other solid tumors. Selectively targeting PI3KαH1047R over PI3KαWT is crucial due to the role that PI3KαWT plays in normal cellular processes, including glucose homeostasis. Currently, only one PI3KαH1047R-selective inhibitor has progressed into clinical trials, while three pan mutant (H1047R, H1047L, H1047Y, E542K, and E545K) selective PI3Kα inhibitors have also reached the clinical stage. Herein, we report the design and discovery of a series of pyridopyrimidinones that inhibit PI3KαH1047R with high selectivity over PI3KαWT, resulting in the discovery of compound 17. When dosed in the HCC1954 tumor model in mice, 17 provided tumor regressions and a clear pharmacodynamic response. X-ray cocrystal structures from several PI3Kα inhibitors were obtained, revealing three distinct binding modes within PI3KαH1047R including a previously reported cryptic pocket in the C-terminus of the kinase domain wherein we observe a ligand-induced interaction with Arg1047.
Collapse
Affiliation(s)
| | | | - Ruth Aranda
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Athenea N. Aloiau
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Briana M. Bobek
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - David M. Briere
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Aaron C. Burns
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | | | - Andrew Calinisan
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Jeffery Clarine
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Adam Elliott
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Lars D. Engstrom
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Robin J. Gunn
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Anthony Ivetac
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Benjamin Jones
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Jon Kuehler
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - J. David Lawson
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Natalie Nguyen
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Cody Parker
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Kelly E. Pearson
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Lisa Rahbaek
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Barbara Saechao
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Xiaolun Wang
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Anna Waters
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Laura Waters
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Ashlee H. Watkins
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Peter Olson
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Christopher R. Smith
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - James G. Christensen
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Matthew A. Marx
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| |
Collapse
|
2
|
Sabari JK, Velcheti V, Shimizu K, Strickland MR, Heist RS, Singh M, Nayyar N, Giobbie-Hurder A, Digumarthy SR, Gainor JF, Rajan AP, Nieblas-Bedolla E, Burns AC, Hallin J, Olson P, Christensen JG, Kurz SC, Brastianos PK, Wakimoto H. Activity of Adagrasib (MRTX849) in Brain Metastases: Preclinical Models and Clinical Data from Patients with KRASG12C-Mutant Non-Small Cell Lung Cancer. Clin Cancer Res 2022; 28:3318-3328. [PMID: 35404402 PMCID: PMC9662862 DOI: 10.1158/1078-0432.ccr-22-0383] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 03/07/2022] [Accepted: 04/04/2022] [Indexed: 01/07/2023]
Abstract
PURPOSE Patients with KRAS-mutant non-small cell lung cancer (NSCLC) with brain metastases (BM) have a poor prognosis. Adagrasib (MRTX849), a potent oral small-molecule KRASG12C inhibitor, irreversibly and selectively binds KRASG12C, locking it in its inactive state. Adagrasib has been optimized for favorable pharmacokinetic properties, including long half-life (∼24 hours), extensive tissue distribution, dose-dependent pharmacokinetics, and central nervous system penetration; however, BM-specific antitumor activity of KRASG12C inhibitors remains to be fully characterized. EXPERIMENTAL DESIGN A retrospective database query identified patients with KRAS-mutant NSCLC to understand their propensity to develop BM. Preclinical studies assessed physiochemical and pharmacokinetic properties of adagrasib. Mice bearing intracranial KRASG12C-mutant NSCLC xenografts (LU99-Luc/H23-Luc/LU65-Luc) were treated with clinically relevant adagrasib doses, and levels of adagrasib in plasma, cerebrospinal fluid (CSF), and brain were determined along with antitumor activity. Preliminary clinical data were collected from 2 patients with NSCLC with untreated BM who had received adagrasib 600 mg twice daily in the phase Ib cohort of the KRYSTAL-1 trial; CSF was collected, adagrasib concentrations measured, and antitumor activity in BM evaluated. RESULTS Patients with KRAS-mutant NSCLC demonstrated high propensity to develop BM (≥40%). Adagrasib penetrated into CSF and demonstrated tumor regression and extended survival in multiple preclinical BM models. In 2 patients with NSCLC and untreated BM, CSF concentrations of adagrasib measured above the target cellular IC50. Both patients demonstrated corresponding BM regression, supporting potential clinical activity of adagrasib in the brain. CONCLUSIONS These data support further development of adagrasib in patients with KRASG12C-mutant NSCLC with untreated BM. See related commentary by Kommalapati and Mansfield, p. 3179.
Collapse
Affiliation(s)
- Joshua K. Sabari
- Laura and Isaac Perlmutter Cancer Center, NYU Langone, New York, New York.,Corresponding Author: Joshua K. Sabari, Laura and Isaac Perlmutter Cancer Center, NYU Langone, New York, NY 10016. Phone: 212-731-5662; E-mail:
| | - Vamsidhar Velcheti
- Laura and Isaac Perlmutter Cancer Center, NYU Langone, New York, New York
| | - Kazuhide Shimizu
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.,Tokyo Medical and Dental University, Tokyo, Japan
| | - Matthew R. Strickland
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.,Dana-Farber Cancer Institute, Boston, Massachusetts
| | - Rebecca S. Heist
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Mohini Singh
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Naema Nayyar
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | | | - Subba R. Digumarthy
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Justin F. Gainor
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Anant P. Rajan
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | | | | | - Jill Hallin
- Mirati Therapeutics, Inc., San Diego, California
| | - Peter Olson
- Mirati Therapeutics, Inc., San Diego, California
| | | | - Sylvia C. Kurz
- Laura and Isaac Perlmutter Cancer Center, NYU Langone, New York, New York
| | | | - Hiroaki Wakimoto
- Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
3
|
Ketcham JM, Haling J, Khare S, Bowcut V, Briere DM, Burns AC, Gunn RJ, Ivetac A, Kuehler J, Kulyk S, Laguer J, Lawson JD, Moya K, Nguyen N, Rahbaek L, Saechao B, Smith CR, Sudhakar N, Thomas NC, Vegar L, Vanderpool D, Wang X, Yan L, Olson P, Christensen JG, Marx MA. Design and Discovery of MRTX0902, a Potent, Selective, Brain-Penetrant, and Orally Bioavailable Inhibitor of the SOS1:KRAS Protein-Protein Interaction. J Med Chem 2022; 65:9678-9690. [PMID: 35833726 PMCID: PMC9340770 DOI: 10.1021/acs.jmedchem.2c00741] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
![]()
SOS1 is one of the major guanine nucleotide exchange
factors that
regulates the ability of KRAS to cycle through its “on”
and “off” states. Disrupting the SOS1:KRASG12C protein–protein interaction (PPI) can increase the proportion
of GDP-loaded KRASG12C, providing a strong mechanistic
rationale for combining inhibitors of the SOS1:KRAS complex with inhibitors
like MRTX849 that target GDP-loaded KRASG12C. In this report,
we detail the design and discovery of MRTX0902—a potent, selective,
brain-penetrant, and orally bioavailable SOS1 binder that disrupts
the SOS1:KRASG12C PPI. Oral administration of MRTX0902
in combination with MRTX849 results in a significant increase in antitumor
activity relative to that of either single agent, including tumor
regressions in a subset of animals in the MIA PaCa-2 tumor mouse xenograft
model.
Collapse
Affiliation(s)
- John M Ketcham
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Jacob Haling
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Shilpi Khare
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Vickie Bowcut
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - David M Briere
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Aaron C Burns
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Robin J Gunn
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Anthony Ivetac
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Jon Kuehler
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Svitlana Kulyk
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Jade Laguer
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - J David Lawson
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Krystal Moya
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Natalie Nguyen
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Lisa Rahbaek
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Barbara Saechao
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Christopher R Smith
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Niranjan Sudhakar
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Nicole C Thomas
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Laura Vegar
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Darin Vanderpool
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Xiaolun Wang
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Larry Yan
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Peter Olson
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - James G Christensen
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| | - Matthew A Marx
- Mirati Therapeutics, 3545 Cray Court, San Diego, California 92121, United States
| |
Collapse
|
4
|
Ketcham JM, Briere DM, Burns AC, Christensen JG, Gunn RJ, Haling J, Ivetac A, Khare S, Kuehler J, Kulyk S, Laguer J, Lawson JD, Moya K, Nguyen N, Olson P, Rahbaek L, Smith CR, Sudhakar N, Thomas NC, Vanderpool D, Wang X, Marx MA. Abstract LB505: Design and discovery of MRTX0902, a potent, selective, and orally bioavailable SOS1 inhibitor. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-lb505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
KRAS mutations are the most common activating mutations in human cancer that ultimately lead to hyperactivation of the MAPK pathway and uncontrolled growth. KRAS functions as a small GTPase that cycles through its GTP-loaded “on” state and its GDP-loaded “off” state, a highly regulated process that is crucial for normal cell proliferation and survival. The guanine nucleotide exchange factor (GEF) SOS1 plays a critical role in this process by regulating the “on/off” state of KRAS. The protein-protein interaction between SOS1 and KRAS facilitates turnover of KRAS from the GDP-loaded inactive state to its activated and GTP-loaded state, a critical step to enable productive KRAS effector binding and activation of downstream signaling. The KRASG12C inhibitor, adagrasib (MRTX849), irreversibly binds to the GDP-loaded inactive conformation of KRASG12C and has recently shown encouraging clinical activity across several cancer types. As adagrasib binds preferentially to the inactive state of KRAS, blockade of SOS1 is anticipated to shift KRASG12C into the adagrasib-susceptible GDP-loaded state. Furthermore, this combination strategy could be used to target other mutant-driven cancers within the MAPK pathway using the appropriate KRASmut inhibitors and/or inhibitors of other targets within the MAPK pathway including MEK or EGFR. MRTX0902 was identified using iterative structure-based design as a selective inhibitor of SOS1 that demonstrates an IC50 value of 2 nM in a SOS1 HTRF binding assay and 30 nM in an MKN1 cellular assay. In pharmacokinetic evaluation across species, MRTX0902 demonstrated low extraction ratios and moderate to high bioavailability in mice, rats, and dogs. In preclinical models, MRTX0902 augmented the antitumor activity of adagrasib and other selected therapies. The design, discovery, and preclinical characterization of the potential best-in-class candidate MRTX0902 will be described.
Citation Format: John M. Ketcham, David M. Briere, Aaron C. Burns, James G. Christensen, Robin J. Gunn, Jacob Haling, Anthony Ivetac, Shilpi Khare, Jon Kuehler, Svitlana Kulyk, Jade Laguer, John D. Lawson, Krystal Moya, Natalie Nguyen, Peter Olson, Lisa Rahbaek, Christopher R. Smith, Niranjan Sudhakar, Nicole C. Thomas, Darin Vanderpool, Xiaolun Wang, Matthew A. Marx. Design and discovery of MRTX0902, a potent, selective, and orally bioavailable SOS1 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB505.
Collapse
|
5
|
Ketcham JM, Khare S, Sudhakar N, Briere DM, Yan L, Laguer J, Vegar L, Vanderpool D, Hallin J, Hargis L, Bowcut V, Lawson D, Gunn RJ, Ivetac A, Thomas NC, Saechao B, Nguyen N, Clarine J, Rahbaek L, Smith CR, Burns AC, Marx MA, Christensen JG, Olson P, Haling JR. Abstract ND02: MRTX0902: A SOS1 inhibitor for therapeutic intervention of KRAS-driven cancers. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-nd02] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
KRAS is the most frequently mutated oncogene in cancer and drives uncontrolled growth through hyperactivation of the MAPK pathway. Significant progress has been made in the past several years to directly target KRASG12C with the FDA approval of sotorasib and the reported clinical activity of adagrasib (MRTX849). Despite these remarkable breakthroughs, additional therapies that enhance the depth and duration of response to KRASG12C inhibitors provide the opportunity to build upon the initial progress. SOS proteins are guanine nucleotide exchange factors (GEFs) that transduce receptor tyrosine kinase (RTK) signaling from the cell surface and facilitate the activation of RAS family proteins. In addition, SOS1 is a target of negative feedback signaling following RAS-mediated activation of the RAF-MEK-ERK cascade. Thus, SOS proteins represent a significant therapeutic node that maintains RAS pathway equilibrium as well as oncogenic signaling dynamics. Here we highlight the discovery and preclinical evaluation of MRTX0902, a potent, selective, and orally bioavailable inhibitor of SOS1 presently in IND-enabling studies. A structure-based approach was used to identify a novel chemical series that disrupts the protein-protein interaction between SOS1 and KRAS, thereby preventing SOS1-mediated GTP-exchange on GDP-bound KRAS. Considering MRTX849 preferentially binds to inactive GDP-bound KRASG12C, targeting SOS1 in this genetic context increases the ability of MRTX849 to bind and inhibit KRASG12C. The combination of MRTX0902 with MRTX849 enhances the depth and durability of an anti-tumor response when compared to MRTX849 alone in pre-clinical KRASG12C tumor models. MRTX0902 augments additional targeted therapies across a variety of RAS-addicted tumors, indicating that SOS1 inhibition is effective against a broad spectrum of mutations within the MAPK pathway. Furthermore, drug-anchored CRISPR experiments with MRTX0902 and MRTX849 uncovered a previously underappreciated functional role of the SOS1 paralog, SOS2, in KRAS-addicted tumors. In addition to aiding in the understanding of SOS and RAS family signaling dynamics, these studies implicate SOS2 as a potential cancer drug target in the context of SOS1/KRASG12C inhibition. In summary, we have used a structure-based approach to discover a SOS1 inhibitor that augments the anti-tumor activity of MRTX849 and additional targeted MAPK pathway inhibitors. We anticipate our findings to translate into the clinic and make an impact in patients with RAS-addicted tumors.
Citation Format: John M. Ketcham, Shilpi Khare, Niranjan Sudhakar, David M. Briere, Larry Yan, Jade Laguer, Laura Vegar, Darin Vanderpool, Jill Hallin, Lauren Hargis, Vickie Bowcut, David Lawson, Robin J. Gunn, Anthony Ivetac, Nicole C. Thomas, Barbara Saechao, Natalie Nguyen, Jeffrey Clarine, Lisa Rahbaek, Christopher R. Smith, Aaron C. Burns, Matthew A. Marx, James G. Christensen, Peter Olson, Jacob R. Haling. MRTX0902: A SOS1 inhibitor for therapeutic intervention of KRAS-driven cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr ND02.
Collapse
Affiliation(s)
| | | | | | | | - Larry Yan
- 1Mirati Therapeutics, Inc, San Diego, CA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Shimizu K, Hallin J, Singh M, Nayyar N, Strickland MR, Burns AC, Cilliers C, Hargis L, Olson PA, Marx MA, Brastianos PK, Wakimoto H, Christensen JG. Abstract 1841: MRTX849 inhibits P-gp and demonstrates CNS exposure in mouse models and cancer patients and demonstrates antitumor activity in intracranial mouse models of lung cancer brain metastasis. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-1841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
MRTX849 is a covalent, mutant selective, KRAS G12C inhibitor in development for cancer patients harboring this mutation. KRAS G12C is mutated in ~14% of lung adenocarcinoma and KRAS G12C inhibitors adagrasib and sotorasib have demonstrated clinical activity. While early data are encouraging, approximately one-third of KRAS-mutant non-small cell lung cancer (NSCLC) patients develop brain metastases and this remains a significant unmet medical need. P-glycoprotein 1 (P-gp)-mediated efflux is a major mechanism for the active transport of small molecules out of the CNS. MRTX849 is a P-gp inhibitor and inhibits its own efflux at plasma exposure levels achieved in humans at the 600 mg BID dose level resulting in achieving appreciable drug levels in cerebrospinal fluid (CSF). Total and free-fraction adjusted plasma concentrations of MRTX849 were 8.6 μM and 43 nM; respectively, 8 hours post administration of a clinically relevant oral dose of 200 mg/kg to mice. In addition, the CSF concentration, a measure of the free brain concentration, was 52 nM, which is above the cellular pERK1/2 IC50 value measured at 24 hours in cancer cell lines (~5 nM). Administration of 100 mg/kg MRTX849 to mice also resulted in CSF exposure above the cellular IC50 and a CSF/plasma (free-fraction adjusted) partition coefficient (Kp,uu) value of 0.4. To evaluate the tumor growth inhibition following oral administration of MRTX849 in an orthotopic model of lung cancer brain metastasis, immunocompromised mice were intracranially implanted with luciferase-labeled human NSCLC LU99 cells. Lower bioluminescence imaging (BLI)-based tumor flux was observed for the 100 mg/kg BID MRTX849-treated mice compared to vehicle and an 88% reduction in bioluminescence signal compared to baseline was observed suggesting strong tumor regression and consistent with significantly longer survival in treated mice. In addition, MRTX849 treated brain tumors demonstrated 85% reduced ERK phosphorylation. Similarly, treatment with MRTX849 resulted in potent tumor regression and significant survival extension in another intracranial KRAS G12C model of NSCLC using LU65 cells. CSF levels were determined at steady-state in two patients in the MRTX849-001 Phase1/2 clinical trial. The CSF/plasma (free fraction adjusted) Kp,uu value was 0.47 with patient CSF levels achieved consistent with CSF levels observed in responding mouse models (24-35 nM). These data demonstrate MRTX849 crosses the blood brain barrier in preclinical models and cancer patients. In addition, antitumor activity observed in mouse models of brain metastases provides rationale for exploring the utility of MRTX849 for the treatment of patients harboring KRAS G12C mutant lung cancer with brain metastases.
Citation Format: Kazuhide Shimizu, Jill Hallin, Mohini Singh, Naema Nayyar, Matthew R. Strickland, Aaron C. Burns, Cornelius Cilliers, Lauren Hargis, Peter A. Olson, Matthew A. Marx, Priscilla K. Brastianos, Hiroaki Wakimoto, James G. Christensen. MRTX849 inhibits P-gp and demonstrates CNS exposure in mouse models and cancer patients and demonstrates antitumor activity in intracranial mouse models of lung cancer brain metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1841.
Collapse
Affiliation(s)
- Kazuhide Shimizu
- 1Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | | - Mohini Singh
- 1Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | - Naema Nayyar
- 1Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | | | | | | | | | | | | | | - Hiroaki Wakimoto
- 1Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | |
Collapse
|
7
|
Smith CR, Aranda R, Bobinski TP, Briere DM, Burns AC, Christensen JG, Clarine J, Engstrom LD, Gunn RJ, Ivetac A, Jean-Baptiste R, Ketcham JM, Kobayashi M, Kuehler J, Kulyk S, Lawson JD, Moya K, Olson P, Rahbaek L, Thomas NC, Wang X, Waters LM, Marx MA. Fragment-Based Discovery of MRTX1719, a Synthetic Lethal Inhibitor of the PRMT5•MTA Complex for the Treatment of MTAP-Deleted Cancers. J Med Chem 2022; 65:1749-1766. [PMID: 35041419 DOI: 10.1021/acs.jmedchem.1c01900] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The PRMT5•MTA complex has recently emerged as a new synthetically lethal drug target for the treatment of MTAP-deleted cancers. Here, we report the discovery of development candidate MRTX1719. MRTX1719 is a potent and selective binder to the PRMT5•MTA complex and selectively inhibits PRMT5 activity in MTAP-deleted cells compared to MTAP-wild-type cells. Daily oral administration of MRTX1719 to tumor xenograft-bearing mice demonstrated dose-dependent inhibition of PRMT5-dependent symmetric dimethylarginine protein modification in MTAP-deleted tumors that correlated with antitumor activity. A 4-(aminomethyl)phthalazin-1(2H)-one hit was identified through a fragment-based screen, followed by X-ray crystallography, to confirm binding to the PRMT5•MTA complex. Fragment growth supported by structural insights from X-ray crystallography coupled with optimization of pharmacokinetic properties aided the discovery of development candidate MRTX1719.
Collapse
Affiliation(s)
| | - Ruth Aranda
- Mirati Therapeutics, San Diego, California 92121, United States
| | | | - David M Briere
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Aaron C Burns
- Mirati Therapeutics, San Diego, California 92121, United States
| | | | - Jeffery Clarine
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Lars D Engstrom
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Robin J Gunn
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Anthony Ivetac
- Mirati Therapeutics, San Diego, California 92121, United States
| | | | - John M Ketcham
- Mirati Therapeutics, San Diego, California 92121, United States
| | | | - Jon Kuehler
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Svitlana Kulyk
- Mirati Therapeutics, San Diego, California 92121, United States
| | - J David Lawson
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Krystal Moya
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Peter Olson
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Lisa Rahbaek
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Nicole C Thomas
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Xiaolun Wang
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Laura M Waters
- Mirati Therapeutics, San Diego, California 92121, United States
| | - Matthew A Marx
- Mirati Therapeutics, San Diego, California 92121, United States
| |
Collapse
|
8
|
Fell JB, Fischer JP, Baer BR, Blake JF, Bouhana K, Briere DM, Brown KD, Burgess LE, Burns AC, Burkard MR, Chiang H, Chicarelli MJ, Cook AW, Gaudino JJ, Hallin J, Hanson L, Hartley DP, Hicken EJ, Hingorani GP, Hinklin RJ, Mejia MJ, Olson P, Otten JN, Rhodes SP, Rodriguez ME, Savechenkov P, Smith DJ, Sudhakar N, Sullivan FX, Tang TP, Vigers GP, Wollenberg L, Christensen JG, Marx MA. Identification of the Clinical Development Candidate MRTX849, a Covalent KRASG12C Inhibitor for the Treatment of Cancer. J Med Chem 2020; 63:6679-6693. [DOI: 10.1021/acs.jmedchem.9b02052] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Jay B. Fell
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - John P. Fischer
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Brian R. Baer
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - James F. Blake
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Karyn Bouhana
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - David M. Briere
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Karin D. Brown
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Laurence E. Burgess
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Aaron C. Burns
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Michael R. Burkard
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Harrah Chiang
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Mark J. Chicarelli
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Adam W. Cook
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - John J. Gaudino
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Jill Hallin
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Lauren Hanson
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Dylan P. Hartley
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Erik J. Hicken
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Gary P. Hingorani
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Ronald J. Hinklin
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Macedonio J. Mejia
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Peter Olson
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Jennifer N. Otten
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Susan P. Rhodes
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Martha E. Rodriguez
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Pavel Savechenkov
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Darin J. Smith
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Niranjan Sudhakar
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Francis X. Sullivan
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Tony P. Tang
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Guy P. Vigers
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - Lance Wollenberg
- Array BioPharma Inc, 3200 Walnut Street, Boulder, Colorado 80301, United States
| | - James G. Christensen
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| | - Matthew A. Marx
- Mirati Therapeutics, 9393 Towne Centre Drive, Suite 200, San Diego, California 92121, United States
| |
Collapse
|
9
|
Bookser BC, Weinhouse MI, Burns AC, Valiere AN, Valdez LJ, Stanczak P, Na J, Rheingold AL, Moore CE, Dyck B. Solvent-Controlled, Site-Selective N-Alkylation Reactions of Azolo-Fused Ring Heterocycles at N1-, N2-, and N3-Positions, Including Pyrazolo[3,4-d]pyrimidines, Purines, [1,2,3]Triazolo[4,5]pyridines, and Related Deaza-Compounds. J Org Chem 2018; 83:6334-6353. [DOI: 10.1021/acs.joc.8b00540] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
| | | | | | | | | | | | | | - Arnold L. Rheingold
- Department of Chemistry, Crystallography Laboratory, University of California, San Diego, Urey Hall 5128, mail code 0358, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| | - Curtis E. Moore
- Department of Chemistry, Crystallography Laboratory, University of California, San Diego, Urey Hall 5128, mail code 0358, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| | | |
Collapse
|
10
|
Burns AC, Sletten TL, Magee M, Hawi Z, Nicholas CL, Saxena R, Ftouni S, Grunstein R, Kennaway D, Ferguson S, Lockley SW, Rajaratnam SW, Cain SW. 0029 BDNF VAL66MET POLYMORPHISM IMPACTS ALERTNESS AND PERFORMANCE IN SHIFT WORKERS. Sleep 2017. [DOI: 10.1093/sleepj/zsx050.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
11
|
Abstract
Salvinorin A (1) is natural hallucinogen that binds the human κ-opioid receptor. A total synthesis has been developed that parlays the stereochemistry of l-(+)-tartaric acid into that of (-)-1 via an unprecedented allylic dithiane intramolecular Diels-Alder reaction to obtain the trans-decalin scaffold. Tsuji allylation set the C9 quaternary center and a late-stage stereoselective chiral ligand-assisted addition of a 3-titanium furan upon a C12 aldehyde/C17 methyl ester established the furanyl lactone moiety. The tartrate diol was finally converted into the C1,C2 keto-acetate.
Collapse
Affiliation(s)
- Nathan J Line
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Ave., Columbus, OH, 43210, USA
| | - Aaron C Burns
- Dart NeuroScience LLC, 12278 Scripps Summit Dr., San Diego, CA, 92131, USA
| | - Sean C Butler
- Department of Chemistry and Biochemistry, The University of Texas at Tyler, 3900 University Blvd., Tyler, TX, 75799, USA
| | - Jerry Casbohm
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Ave., Columbus, OH, 43210, USA
| | - Craig J Forsyth
- Department of Chemistry and Biochemistry, The Ohio State University, 100 W. 18th Ave., Columbus, OH, 43210, USA
| |
Collapse
|
12
|
Gianatassio R, Kawamura S, Eprile CL, Foo K, Ge J, Burns AC, Collins MR, Baran PS. Simple sulfinate synthesis enables C-H trifluoromethylcyclopropanation. Angew Chem Int Ed Engl 2014; 53:9851-5. [PMID: 25088979 DOI: 10.1002/anie.201406622] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Indexed: 12/16/2022]
Abstract
A simple method to convert readily available carboxylic acids into sulfinate salts by employing an interrupted Barton decarboxylation reaction is reported. A medicinally oriented panel of ten new sulfinate reagents was created using this method, including a key trifluoromethylcyclopropanation reagent, TFCS-Na. The reactivity of six of these salts towards C-H functionalization was field-tested using several different classes of heterocycles.
Collapse
Affiliation(s)
- Ryan Gianatassio
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037 (USA)
| | | | | | | | | | | | | | | |
Collapse
|
13
|
Gianatassio R, Kawamura S, Eprile CL, Foo K, Ge J, Burns AC, Collins MR, Baran PS. Simple Sulfinate Synthesis Enables CH Trifluoromethylcyclopropanation. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201406622] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
14
|
Gui J, Zhou Q, Pan CM, Yabe Y, Burns AC, Collins MR, Ornelas MA, Ishihara Y, Baran PS. C-H methylation of heteroarenes inspired by radical SAM methyl transferase. J Am Chem Soc 2014; 136:4853-6. [PMID: 24611732 PMCID: PMC3988686 DOI: 10.1021/ja5007838] [Citation(s) in RCA: 153] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
![]()
A practical C–H functionalization
method for the methylation
of heteroarenes is presented. Inspiration from Nature’s methylating
agent, S-adenosylmethionine (SAM), allowed for the
design and development of zinc bis(phenylsulfonylmethanesulfinate),
or PSMS. The action of PSMS on a heteroarene generates a (phenylsulfonyl)methylated
intermediate that can be easily separated from unreacted starting
material. This intermediate can then be desulfonylated to the methylated
product or elaborated to a deuteriomethylated product, and can divergently
access medicinally important motifs. This mild, operationally simple
protocol that can be conducted in open air at room temperature is
compatible with sensitive functional groups for the late-stage functionalization
of pharmacologically relevant substrates.
Collapse
Affiliation(s)
- Jinghan Gui
- Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
O'Hara F, Burns AC, Collins MR, Dalvie D, Ornelas MA, Vaz ADN, Fujiwara Y, Baran PS. A simple litmus test for aldehyde oxidase metabolism of heteroarenes. J Med Chem 2014; 57:1616-20. [PMID: 24472070 PMCID: PMC3983350 DOI: 10.1021/jm4017976] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The
bioavailability of aromatic azaheterocyclic drugs can be affected
by the activity of aldehyde oxidase (AO). Susceptibility to AO metabolism
is difficult to predict computationally and can be complicated in
vivo by differences between species. Here we report the use of bis(((difluoromethyl)sulfinyl)oxy)zinc
(DFMS) as a source of CF2H radical for a rapid and inexpensive
chemical “litmus test” for the early identification
of heteroaromatic drug candidates that have a high probability of
metabolism by AO.
Collapse
Affiliation(s)
- Fionn O'Hara
- Department of Chemistry, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Trost BM, Masters JT, Burns AC. Palladium-catalyzed asymmetric allylic alkylation of 3-aryloxindoles with allylidene dipivalate: a useful enol pivalate product. Angew Chem Int Ed Engl 2013; 52:2260-4. [PMID: 23335176 PMCID: PMC3825682 DOI: 10.1002/anie.201209783] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Indexed: 11/12/2022]
Affiliation(s)
- Barry M Trost
- Department of Chemistry, Stanford University, Stanford, CA 94305-4401, USA.
| | | | | |
Collapse
|
17
|
Trost BM, Masters JT, Burns AC. Palladium-Catalyzed Asymmetric Allylic Alkylation of 3-Aryloxindoles with Allylidene Dipivalate: A Useful Enol Pivalate Product. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201209783] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
18
|
Trost BM, Burns AC, Bartlett MJ, Tautz T, Weiss AH. Thionium ion initiated medium-sized ring formation: the total synthesis of asteriscunolide D. J Am Chem Soc 2012; 134:1474-7. [PMID: 22236456 DOI: 10.1021/ja210986f] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The first synthesis of the biologically active humulene natural product asteriscunolide D has been accomplished in nine steps without the use of protecting groups. The challenging 11-membered ring was forged via a diastereoselective thionium ion initiated cyclization, which constitutes a formal aldol disconnection to form a strained macrocycle. A stereospecific thioether activation-elimination protocol was developed for selective E-olefin formation, thus providing access to the most biologically active asteriscunolide. The absolute stereochemical configuration was established by the Zn-ProPhenol catalyzed enantioselective addition of methyl propiolate to an aliphatic aldehyde to afford a γ-hydroxy propiolate as a handle for butenolide formation via Ru-catalyzed alkene-alkyne coupling.
Collapse
Affiliation(s)
- Barry M Trost
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
| | | | | | | | | |
Collapse
|
19
|
Trost BM, Burns AC, Tautz T. Readily Accessible Chiral Diene Ligands for Rh-Catalyzed Enantioselective Conjugate Additions of Boronic Acids. Org Lett 2011; 13:4566-9. [DOI: 10.1021/ol201754c] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Barry M. Trost
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States
| | - Aaron C. Burns
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States
| | - Thomas Tautz
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States
| |
Collapse
|
20
|
Abstract
Various functionalized steroidal side chains were conveniently accessed by a modified Julia olefination strategy using a common sulfone donor and an appropriate α-branched aldehyde acceptor. For the coupling of these hindered classes of reaction partners (and in contrast to typically observed trends), the benzothiazolyl(BT)-sulfone anion gave superior outcomes compared to the phenyltetrazolyl(PT)-sulfone anion.
Collapse
Affiliation(s)
- Enver Cagri Izgu
- Department of Chemistry, 207 Pleasant Street, SE, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | |
Collapse
|
21
|
Burns AC, Sorensen PW, Hoye TR. Synthesis and olfactory activity of unnatural, sulfated 5β-bile acid derivatives in the sea lamprey (Petromyzon marinus). Steroids 2011; 76:291-300. [PMID: 21145335 PMCID: PMC3062205 DOI: 10.1016/j.steroids.2010.11.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 11/28/2010] [Accepted: 11/30/2010] [Indexed: 11/16/2022]
Abstract
A variety of unnatural bile acid derivatives (9a-9f) was synthesized and used to examine the specificity with which the sea lamprey (Petromyzon marinus) olfactory system detects these compounds. These compounds are analogs of petromyzonol sulfate (PS, 1), a component of the sea lamprey migratory pheromone. Both the stereochemical configuration at C5 (i.e., 5α vs. 5β) and the extent and sites of oxygenation (hydroxylation or ketonization) of the bile acid derived steroid skeleton were evaluated by screening the compounds for olfactory activity using electro-olfactogram recording. 5β-Petromyzonol sulfate (9a) elicited a considerable olfactory response at sub-nanomolar concentration. In addition, less oxygenated systems (i.e., 9b-9e) elicited olfactory responses, albeit with less potency. The sea lamprey sex pheromone mimic 9f (5β-3-ketopetromyzonol sulfate) was also examined and found to produce a much lower olfactory response. Mixture studies conducted with 9a and PS (1) suggest that stimulation is occurring via similar modes of activation, demonstrating a relative lack of specificity for recognition of the allo-configuration (i.e., 5α) in sea lamprey olfaction. This attribute could facilitate design of pheromone analogs to control this invasive species.
Collapse
Affiliation(s)
- Aaron C. Burns
- Department of Chemistry, College of Science and Engineering, University of Minnesota, Minneapolis, MN 55455 612-625-1891
| | - Peter W. Sorensen
- Department of Fisheries, Wildlife and Conservation Biology, College of Food, Agriculture, and Natural Science, University of Minnesota, St. Paul, MN 55108
| | - Thomas R. Hoye
- Department of Chemistry, College of Science and Engineering, University of Minnesota, Minneapolis, MN 55455 612-625-1891
| |
Collapse
|
22
|
Abstract
An enantioselective synthesis of the highly functionalized trans-decalin core (2) of salvinorin A is described. The tetraene 4 was synthesized in six steps from a known L-(+)-tartaric acid derivative. Three contiguous stereocenters, two of them quaternary, on the trans-decalin were established asymmetrically by an intramolecular Diels-Alder/Tsuji allylation sequence.
Collapse
Affiliation(s)
- Aaron C Burns
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | |
Collapse
|
23
|
Burns AC, Osula S, Harley A, Rashid A. Left circumflex coronary artery to left atrial fistula in a patient with mitral regurgitation after excision of a left atrial myxoma. Ann Thorac Surg 2001; 72:1732-3. [PMID: 11722076 DOI: 10.1016/s0003-4975(01)02613-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Acquired coronary artery to left atrial fistulas are rare and previously only described in mitral stenosis associated with left atrial thrombus or coronary arteriosclerosis. We present the case of a patient who developed a left circumflex coronary artery to left atrial fistula associated with mitral regurgitation 12 years after excision of a left atrial myxoma. This was successfully ligated at the time of mitral valve replacement.
Collapse
Affiliation(s)
- A C Burns
- Division of Cardiothoracic Surgery, The Cardiothoracic Centre-Liverpool NHS Trust, United Kingdom
| | | | | | | |
Collapse
|
24
|
Abstract
PURPOSE Erythema multiforme and Stevens-Johnson syndrome have been associated with anticonvulsant medications (AEDs) in patients with brain tumors receiving cranial irradiation. AEDs are also known to cause mild drug rashes. The incidence of these complications has not been well studied among patients with brain tumors. We reviewed the records of patients with brain tumors treated with cranial radiation and AEDs to assess the frequency of both severe and mild skin reactions. METHODS Retrospective review of 289 radiotherapy records of consecutively treated patients from 1988 to 1993. RESULTS Only one of 289 patients developed erythema multiforme. Milder rashes, however, occurred in 18% of exposures to AEDs including 22% of exposures to phenytoin, compared with the expected rate of 5-10%. Most of the mild drug rashes occurred before the initiation of radiotherapy, suggesting that radiation was not the cause of these reactions. CONCLUSIONS Severe skin rashes are rare among patients with brain tumors receiving radiation therapy and AEDs. There is, however, an increased frequency of mild drug rashes among patients with brain tumors that does not appear related to radiation.
Collapse
Affiliation(s)
- H J Mamon
- Department of Radiation Therapy, Joint Center for Radiation Therapy, Boston, Massachusetts 02215, USA
| | | | | | | |
Collapse
|
25
|
Reiber KB, Burns AC, Oxley DW, Gormley WT. The medical examiner in war. J Forensic Sci 1995; 40:197-200. [PMID: 7602276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Loss of human life is one of the tragic costs of war. While combat deaths are expected, non-combat deaths during a military operation often come as a surprise to military planners and the public. During operation Desert Storm, all United States deaths related to the Gulf War were classified according to circumstances as either hostile or non-hostile. We reviewed all deaths classified as non-hostile during Operation Desert Storm, from January 16, 1991 through April 17, 1991. These deaths were compared with the death recorded for all Armed Forces personnel during a recent year (fiscal year 1989) in which there was no hostile activity. The emphasis is on cause and manner of death. Representative cases are briefly discussed.
Collapse
Affiliation(s)
- K B Reiber
- Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology, Washington DC, USA
| | | | | | | |
Collapse
|
26
|
Burns AC. The expanded health belief model as a basis for enlightened preventive health care practice and research. J Health Care Mark 1992; 12:32-45. [PMID: 10120533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The health belief model has served as the primary theoretical vehicle for preventive health care research and practitioner guidelines for the past two decades. However, it has been criticized for its rational belief tenets. An expanded health belief model is proposed that explicitly incorporates a process orientation and adds several constructs with good potential to explain difficulties practitioners encounter in fostering realization of health risks and/or gaining long-term compliance with preventive health care recommendations. Illustrative practitioner implications are described and an agenda for research on the expanded model is outlined.
Collapse
|
27
|
Nelson RJ, Perry S, Burns AC, Roberts J, Pickard JD. The effects of hyponatraemia and subarachnoid haemorrhage on the cerebral vasomotor responses of the rabbit. J Cereb Blood Flow Metab 1991; 11:661-6. [PMID: 2050754 DOI: 10.1038/jcbfm.1991.118] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Impairment of cerebral autoregulation and development of hyponatraemia are both implicated in the pathogenesis of delayed cerebral ischaemia and infarction following subarachnoid haemorrhage (SAH) but the pathophysiology and interactions involved are not fully understood. We have studied the effects of hyponatraemia and SAH on the cerebral vasomotor responses of the rabbit. Cerebrovascular reactivity to hypercapnia and cerebral autoregulation to trimetaphan-induced hypotension were determined in normal and hyponatraemic rabbits before and 6 days after experimental SAH produced by two intracisternal injections of autologous blood. Hyponatraemia (mean plasma sodium of 119 mM) was induced gradually over 48 h by administration of Desmopressin and intraperitoneal 5% dextrose. Sham animals received normal saline. The cerebrovascular reactivity (% change +/- SD in cortical CBF/mm Hg PaCO2, measured by hydrogen clearance) of hyponatraemic (4.8 +/- 3.0%) and SAH (1.3 +/- 2.0%) animals was significantly less (p less than 0.05) than control (11.6 +/- 4.0%) and sham (8 +/- 2.0%) animals, whereas the reactivity of hyponatraemic-SAH animals was preserved (9.8 +/- 6.0%). Hyponatraemia and SAH alone each significantly impaired CBF autoregulation but their combined effects were not additive. Systemic hyponatraemia impairs normal cerebral vasomotor responses but does not augment the effects of experimental SAH in the rabbit.
Collapse
Affiliation(s)
- R J Nelson
- Wessex Neurological Centre, Southampton General Hospital, England
| | | | | | | | | |
Collapse
|
28
|
Burns AC, Steger HG. Intervention strategies for victims of work-related burn injuries. Occup Health Nurs 1983; 31:29-44. [PMID: 6554572 DOI: 10.1177/216507998303100708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
|
29
|
Burns AC. Hotel fires safety tips. Am J Forensic Med Pathol 1981; 2:280. [PMID: 7325142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
|