| 1. |
- Bonagas, Nadilly, et al.
(författare)
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Pharmacological targeting of MTHFD2 suppresses acute myeloid leukemia by inducing thymidine depletion and replication stress
- 2022
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Ingår i: NATURE CANCER. - : Springer Science and Business Media LLC. - 2662-1347. ; 3:2, s. 156-
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Tidskriftsartikel (refereegranskat)abstract
- The folate metabolism enzyme MTHFD2 (methylenetetrahydrofolate dehydrogenase/cyclohydrolase) is consistently overexpressed in cancer but its roles are not fully characterized, and current candidate inhibitors have limited potency for clinical development. In the present study, we demonstrate a role for MTHFD2 in DNA replication and genomic stability in cancer cells, and perform a drug screen to identify potent and selective nanomolar MTHFD2 inhibitors; protein cocrystal structures demonstrated binding to the active site of MTHFD2 and target engagement. MTHFD2 inhibitors reduced replication fork speed and induced replication stress followed by S-phase arrest and apoptosis of acute myeloid leukemia cells in vitro and in vivo, with a therapeutic window spanning four orders of magnitude compared with nontumorigenic cells. Mechanistically, MTHFD2 inhibitors prevented thymidine production leading to misincorporation of uracil into DNA and replication stress. Overall, these results demonstrate a functional link between MTHFD2-dependent cancer metabolism and replication stress that can be exploited therapeutically with this new class of inhibitors. Helleday and colleagues describe a nanomolar MTHFD2 inhibitor that causes replication stress and DNA damage accumulation in cancer cells via thymidine depletion, demonstrating a potential therapeutic strategy in AML tumors in vivo.
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| 2. |
- Gustafsson, Robert, 1988-
(författare)
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Structural and functional studies of proteins of medical relevance : Protein-ligand complexes in cancer and novel structural folds in bacteria
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- X-ray crystallography is a tool for determining the structures of proteins and protein-ligand complexes. In this thesis the method has been employed to study several proteins of medical relevance.Cancer is a terrible disease, severely impacting those affected, as well as their family and friends. Current cancer treatments involve a combination of cytostatic drugs, surgery and radiation treatment. Unfortunately many cytostatic drugs also kill healthy cells, which gives rise to serious side-effects. The discovery of treatments which selectively inhibit proteins essential for cancer cell survival but which are non-essential in normal cells, could reduce such side-effects.MTH1 is a protein that degrades oxidised nucleotides, which when incorporated into DNA cause mutations and subsequent cell death. Cancer cells have higher levels of reactive oxygen species, which create oxidised nucleotides. In Paper I it was discovered that cancer cells are dependent on MTH1 for their survival. Crystal structures of MTH1 in complex with small molecules guided their development into potent MTH1 inhibitors, capable of killing cancer cells. Cells with increased amounts of oxidised nucleotides, or with induced hypoxia, were more susceptible to MTH1 inhibition, as shown in Paper II. In Paper III several MTH1 orthologues from organisms often used in pre-clinical studies were tested for MTH1 inhibition. Leucine 116 of mouse MTH1 was determined to be important for the lower inhibition of the developed inhibitors towards this enzyme. A virtual fragment screening study using commercial chemicals resulted in several potent MTH1 inhibitors, as shown in Paper IV. The crystal structures with the fragments or optimised inhibitors did in most cases agree with the docking pose determined from the virtual screening. In addition to the known function of MTH1 in the degradation of oxidised nucleotides, Paper V showed that MTH1 also degrades methylated nucleotides.MTHFD2 is responsible for providing one-carbon units for nucleotide synthesis in cancer cells. As MTHFD2 is present in cancer cells but not in healthy cells, targeting the enzyme would make it possible to selectively kill cancer cells. Paper VI presents the first structure of MTHFD2, along with the first inhibitor of the protein. This information provides a starting point for the development of potent and selective MTHFD2 inhibitors.The botulinum neurotoxin from the bacterium Clostridium Botulinum is the causative agent of the deadly disease botulism. The action of the botulinum neurotoxin on nerve cells results in paralysis, and is life-threatening if the patient is not helped with breathing support. However, low doses of the neurotoxin are used as a successful treatment for several medical conditions, such as involuntary spasms. In Paper VII the structure of two proteins, P47 and OrfX2, encoded in the gene cluster of a botulinum neurotoxin, were determined. The structures resembled tubular lipid-binding proteins, previously only found in eukaryotes. The proteins were also found to be able to bind lipids. This work gives new insight into the structure and function of this group of proteins, which help the deadly botulinum neurotoxins.
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| 3. |
- Scaletti, Emma Rose, et al.
(författare)
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Structural and functional insights into the Pseudomonas aeruginosa glycosyltransferase WaaG and the implications for lipopolysaccharide biosynthesis
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The glycosyltransferase WaaG in Pseudomonas aeruginosa (PaWaaG) is involved in synthesis of the core region of lipopolysaccharides. It is a promising target for developing adjuvants that could help in the uptake of antibiotics. Herein we have determined structures of PaWaaG in complex with the nucleotide-sugars UDP-glucose, UDP-galactose and UDP-GalNAc. Structural comparison with the homologue from Escherichia coli (EcWaaG) revealed five key differences in the sugar binding pocket. Solution-state NMR analysis showed that wildtype PaWaaG specifically hydrolyzes UDP-GalNAc and unlike EcWaaG, does not hydrolyze UDP-glucose. Furthermore, we found that a PaWaaG mutant (Y97F/T208R/N282A/T283A/T285I) designed to resemble the EcWaaG sugar binding site, only hydrolyzed UDP-glucose, underscoring the importance of the identified amino acids in substrate specificity. However, neither wildtype PaWaaG nor the PaWaaG mutant capable of hydrolyzing UDP-glucose was able to complement an E. coli ΔwaaG strain, indicating that more remains to be uncovered about the function of PaWaaG in vivo. This structural and biochemical information will guide future structure-based drug design efforts targeting PaWaaG.
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| 4. |
- Scaletti, Emma Rose, et al.
(författare)
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The First Structure of Human MTHFD2L and Its Implications for the Development of Isoform-Selective Inhibitors
- 2022
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Ingår i: ChemMedChem. - : Wiley. - 1860-7179 .- 1860-7187. ; 17:18
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Tidskriftsartikel (refereegranskat)abstract
- Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is a mitochondrial 1-carbon metabolism enzyme, which is an attractive anticancer drug target as it is highly upregulated in cancer but is not expressed in healthy adult cells. Selective MTHFD2 inhibitors could therefore offer reduced side-effects during treatment, which are common with antifolate drugs that target other 1C-metabolism enzymes. This task is challenging however, as MTHFD2 shares high sequence identity with the constitutively expressed isozymes cytosolic MTHFD1 and mitochondrial MTHFD2L. In fact, one of the most potent MTHFD2 inhibitors reported to date, TH7299, is actually more active against MTHFD1 and MTHFD2L. While structures of MTHFD2 and MTHFD1 exist, no MTHFD2L structures are available. We determined the first structure of MTHFD2L and its complex with TH7299, which reveals the structural basis for its highly potent MTHFD2L inhibition. Detailed analysis of the MTHFD2L structure presented here clearly highlights the challenges associated with developing truly isoform-selective MTHFD2 inhibitors.
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| 5. |
- Vesting, Florian, 1982, et al.
(författare)
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Procedure for Application-Oriented Optimisation of Marine Propellers
- 2016
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Ingår i: Journal of Marine Science and Engineering. - : MDPI AG. - 2077-1312. ; 4:4, s. 83-
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Tidskriftsartikel (refereegranskat)abstract
- The use of automated optimisation in engineering applications is emerging. In particular, nature inspired algorithms are frequently used because of their variability and robust application in constraints and multi-objective optimisation problems. The purpose of this paper is the comparison of four different algorithms and several optimisation strategies on a set of seven test propellers in realistic industrial design setting. The propellers are picked from real commercial projects and the manual final designs were delivered to customers. The different approaches are evaluated and final results of the automated optimisation toolbox are compared with designs generated in a manual design process. We identify a two-stage optimisation for marine propellers, where the geometry is first modified by parametrised geometry distribution curves to gather knowledge of the test case. Here we vary the optimisation strategy in terms of applied algorithms, constraints and objectives. A second supporting optimisation aims to improve the design by locally changing the geometry, based on the results of the first optimisation. The optimisation algorithms and strategies yield propeller designs that are comparable to the manually designed propeller blade geometries, thus being suitable as robust and advanced design support tools. The supporting optimisation, with local modification of the blade geometry and the proposed cavity shape constraints, features particular good performance in modifying cavitation on the blade and is, with the AS NSGA-II (adaptive surrogate-assisted NSGA-II), superior in lead time.
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