1
|
Yim HJ, Kang SH, Jung YK, Ahn SH, Kim W, Yang JM, Jang JY, Kweon YO, Cho YK, Kim YJ, Hong GY, Kim DJ, Sohn JH, Lee JW, Park SJ, Yim SY, Park JK, Um SH. Reduced Risk of Hepatocellular Carcinoma in Patients with Chronic Hepatitis B Receiving Long-Term Besifovir Therapy. Cancers (Basel) 2024; 16:887. [PMID: 38473248 DOI: 10.3390/cancers16050887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/14/2024] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
No information is available regarding the influence of besifovir (BSV), a new nucleotide analogue, on the occurrence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study evaluated the reduced risk of HCC in patients undergoing BSV treatment. A total of 188 patients with CHB were treated with BSV for up to 8 years. We prospectively assessed the incidence of HCC compared with the risk from prediction models. During the follow-up, 5 patients developed HCC: 1 of 139 patients with non-cirrhotic CHB, and 4 of 49 patients with liver cirrhosis. We compared the HCC incidence in non-cirrhotic and cirrhotic patients with the predicted number derived from the REACH-B (risk estimation for HCC in CHB) model and GAG-HCC (guide with age, gender, HBV DNA, core promotor mutation, and cirrhosis) model, respectively. The standardized incidence ratio (SIR) was 0.128 (p = 0.039) at 7 years in non-cirrhotic CHB patients, and the SIR was 0.371 (p = 0.047) at 7.5 years in cirrhotic patients, suggesting a significantly decreased HCC incidence in both groups. HCC prediction was available for BSV-treated patients using existing models. In conclusion, BSV decreased the risk of HCC in patients with CHB, and prediction models were applicable. Clinical trial registry website and trial number: ClinicalTrials.gov no: NCT01937806.
Collapse
Affiliation(s)
- Hyung Joon Yim
- Department of Internal Medicine, Korea University Ansan Hospital, 123, Jeokgeum-ro, Danwon-gu, Ansan 15355, Republic of Korea
| | - Seong Hee Kang
- Department of Internal Medicine, Korea University Ansan Hospital, 123, Jeokgeum-ro, Danwon-gu, Ansan 15355, Republic of Korea
| | - Young Kul Jung
- Department of Internal Medicine, Korea University Ansan Hospital, 123, Jeokgeum-ro, Danwon-gu, Ansan 15355, Republic of Korea
| | - Sang Hoon Ahn
- Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, 50-1, Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Won Kim
- Department of Internal Medicine, Seoul Metropolitan Government Seoul National University Boramae Medical Center, 20 Boramae-ro 5-gil, Dongjak-gu, Seoul 07061, Republic of Korea
| | - Jin Mo Yang
- Department of Internal Medicine, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, 93 Jungbu-daero, Paldal-gu, Suwon 16247, Republic of Korea
| | - Jae Young Jang
- Department of Internal Medicine, Soonchunhyang University Seoul Hospital, 59, Daesagwan-ro, Yongsan-gu, Seoul 04401, Republic of Korea
| | - Yong Oh Kweon
- Department of Internal Medicine, Kyungpook National University Hospital, 680 gukchaebosang-ro, Jung-gu, Daegu 41944, Republic of Korea
| | - Yong Kyun Cho
- Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 29 Saemunan-ro, Jongno-gu, Seoul 03181, Republic of Korea
| | - Yoon Jun Kim
- Department of Internal Medicine and Liver Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea
| | - Gun Young Hong
- Department of Internal Medicine, Kwangju Christian Hospital, 37 Yangnim-ro, Nam-gu, Gwangju 61661, Republic of Korea
| | - Dong Joon Kim
- Department of Internal Medicine and Center for Liver and Digestive Diseases, Hallym University Chuncheon Sacred Heart Hospital, 77 Sakju-ro, Chuncheon 24253, Republic of Korea
| | - Joo Hyun Sohn
- Department of Internal Medicine, Hanyang University Guri Hospital, 153, Gyeongchun-ro, Guri-si 11923, Republic of Korea
| | - Jin Woo Lee
- Department of Internal Medicine, Inha University Hospital, 27 Inhang-ro, Jung-gu, Incheon 22332, Republic of Korea
| | - Sung Jae Park
- Department of Internal Medicine, Inje University Busan Paik Hospital, 75 Bokji-ro, Busanjin-gu, Busan 47392, Republic of Korea
| | - Sun Young Yim
- Department of Internal Medicine, Korea University Anam Hospital, 73 Goryeodae-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Jin Kyung Park
- Ildong Pharmaceutical Company, 2, Baumoe-ro 27-gil, Seocho-gu, Seoul 06752, Republic of Korea
| | - Soon Ho Um
- Department of Internal Medicine, Korea University Anam Hospital, 73 Goryeodae-ro, Seongbuk-gu, Seoul 02841, Republic of Korea
| |
Collapse
|
2
|
Goebel L, Kirschner T, Koska S, Rai A, Janning P, Maffini S, Vatheuer H, Czodrowski P, Goody RS, Müller MP, Rauh D. Targeting oncogenic KRasG13C with nucleotide-based covalent inhibitors. eLife 2023; 12:82184. [PMID: 36972177 PMCID: PMC10042540 DOI: 10.7554/elife.82184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
Mutations within Ras proteins represent major drivers in human cancer. In this study, we report the structure-based design, synthesis, as well as biochemical and cellular evaluation of nucleotide-based covalent inhibitors for KRasG13C, an important oncogenic mutant of Ras that has not been successfully addressed in the past. Mass spectrometry experiments and kinetic studies reveal promising molecular properties of these covalent inhibitors, and X-ray crystallographic analysis has yielded the first reported crystal structures of KRasG13C covalently locked with these GDP analogues. Importantly, KRasG13C covalently modified with these inhibitors can no longer undergo SOS-catalysed nucleotide exchange. As a final proof-of-concept, we show that in contrast to KRasG13C, the covalently locked protein is unable to induce oncogenic signalling in cells, further highlighting the possibility of using nucleotide-based inhibitors with covalent warheads in KRasG13C-driven cancer.
Collapse
Affiliation(s)
- Lisa Goebel
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Tonia Kirschner
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Sandra Koska
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Amrita Rai
- Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Petra Janning
- Department of Chemical Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Stefano Maffini
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Helge Vatheuer
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Paul Czodrowski
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Roger S Goody
- Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Matthias P Müller
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| | - Daniel Rauh
- Department of Chemistry and Chemical Biology, TU Dortmund University, Dortmund, Germany
| |
Collapse
|
3
|
Pawlowska R, Chworos A. Nucleoside and Nucleotide Analogues as Potential Therapeutics. Curr Med Chem 2023; 30:1207-1208. [PMID: 36872461 DOI: 10.2174/092986733011230106124249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Roza Pawlowska
- Centre of Molecular and Macromolecular Studies of the Polish Academy of Sciences, Sienkiewicza 112 90-363 Lodz, Poland
| | - Arkadiusz Chworos
- Centre of Molecular and Macromolecular Studies of the Polish Academy of Sciences, Sienkiewicza 112 90-363 Lodz, Poland
| |
Collapse
|
4
|
Mikkola S, Eguaogie O, Nieminen A, Conlon PF, Jakeman DL, Moore K, Lane IC, Vyle JS. 5'-Chalcogen-Substituted Nucleoside Pyrophosphate and Phosphate Monoester Analogues: Preparation and Hydrolysis Studies. Int J Mol Sci 2022; 23:ijms232415582. [PMID: 36555224 PMCID: PMC9778984 DOI: 10.3390/ijms232415582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/01/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
Novel sulfur and selenium substituted 5',5'-linked dinucleoside pyrophate analogues were prepared in a vibration ball mill from the corresponding persilylated monophosphate. The chemical hydrolysis of pyrophosphorochalcogenolate-linked dimers was studied over a wide pH-range. The effect of the chalcogeno-substitution on the reactivity of dinucleoside pyrophosphates was surprisingly modest, and the chemical stability is promising considering the potential therapeutic or diagnostic applications. The chemical stability of the precursor phosphorochalcogenolate monoesters was also investigated. Hydrolytic desilylation of these materials was effected in aqueous buffer at pH 3, 7 or 11 and resulted in phosphorus-chalcogen bond scission which was monitored using 31P NMR. The rate of dephosphorylation was dependent upon both the nature of the chalcogen and the pH. The integrity of the P-S bond in the corresponding phosphorothiolate was maintained at high pH but rapidly degraded at pH 3. In contrast, P-Se bond cleavage of the phosphoroselenolate monoester was rapid and the rate increased with alkalinity. The results obtained in kinetic experiments provide insight on the reactivity of the novel pyrophosphates studied as well as of other types of thiosubstituted biological phosphates. At the same time, these results also provide evidence for possible formation of unexpectedly reactive intermediates as the chalcogen-substituted analogues are metabolised.
Collapse
Affiliation(s)
- Satu Mikkola
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland
- Correspondence: (S.M.); (J.S.V.)
| | - Olga Eguaogie
- School of Chemistry and Chemical Engineering, Queen’s University of Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
| | - Anu Nieminen
- Department of Chemistry, University of Turku, FIN-20014 Turku, Finland
| | - Patrick F. Conlon
- School of Chemistry and Chemical Engineering, Queen’s University of Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
- College of Pharmacy, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - David L. Jakeman
- College of Pharmacy, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Keith Moore
- School of Chemistry and Chemical Engineering, Queen’s University of Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
| | - Ian C. Lane
- School of Chemistry and Chemical Engineering, Queen’s University of Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
| | - Joseph S. Vyle
- School of Chemistry and Chemical Engineering, Queen’s University of Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG, UK
- Correspondence: (S.M.); (J.S.V.)
| |
Collapse
|
5
|
Pockros PJ, Mulgaonkar A. Cessation of Nucleoside/Nucleotide Analogue Therapy in Chronic Hepatitis B HBeAg-Negative Patients. Gastroenterol Hepatol (N Y) 2022; 18:320-325. [PMID: 36398137 PMCID: PMC9666823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Most patients treated for chronic hepatitis B infection require lifelong treatment with nucleoside/nucleotide analogues (NAs), which inhibit hepatitis B virus (HBV) replication but do not eradicate the virus or achieve a functional cure. Withdrawal of NA treatment is being considered as a path to functional cure by provoking HBV reactivation, followed by immune consolidation and subsequent hepatitis B surface antigen loss in some patients. However, in rare cases, NA therapy withdrawal causes severe hepatitis flares, hepatic decompensation, or death, and predictors of hepatic decompensation or death with NA withdrawal have not been well established. This article reviews the current standard of care for HBV and the results of recent trials that clarify the safety of NA treatment cessation relative to the benefit of functional cure.
Collapse
Affiliation(s)
- Paul J. Pockros
- Division of Gastroenterology/Hepatology, Scripps Clinic, La Jolla, California
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California
| | - Ashwini Mulgaonkar
- Division of Gastroenterology/Hepatology, Scripps Clinic, La Jolla, California
| |
Collapse
|
6
|
Sigel A, Sigel H, Sigel RKO. Coordination Chemistry of Nucleotides and Antivirally Active Acyclic Nucleoside Phosphonates, including Mechanistic Considerations. Molecules 2022; 27:2625. [PMID: 35565975 PMCID: PMC9103026 DOI: 10.3390/molecules27092625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/08/2022] [Accepted: 04/10/2022] [Indexed: 11/17/2022] Open
Abstract
Considering that practically all reactions that involve nucleotides also involve metal ions, it is evident that the coordination chemistry of nucleotides and their derivatives is an essential corner stone of biological inorganic chemistry. Nucleotides are either directly or indirectly involved in all processes occurring in Nature. It is therefore no surprise that the constituents of nucleotides have been chemically altered-that is, at the nucleobase residue, the sugar moiety, and also at the phosphate group, often with the aim of discovering medically useful compounds. Among such derivatives are acyclic nucleoside phosphonates (ANPs), where the sugar moiety has been replaced by an aliphatic chain (often also containing an ether oxygen atom) and the phosphate group has been replaced by a phosphonate carrying a carbon-phosphorus bond to make the compounds less hydrolysis-sensitive. Several of these ANPs show antiviral activity, and some of them are nowadays used as drugs. The antiviral activity results from the incorporation of the ANPs into the growing nucleic acid chain-i.e., polymerases accept the ANPs as substrates, leading to chain termination because of the missing 3'-hydroxyl group. We have tried in this review to describe the coordination chemistry (mainly) of the adenine nucleotides AMP and ATP and whenever possible to compare it with that of the dianion of 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA2- = adenine(N9)-CH2-CH2-O-CH2-PO32) [or its diphosphate (PMEApp4-)] as a representative of the ANPs. Why is PMEApp4- a better substrate for polymerases than ATP4-? There are three reasons: (i) PMEA2- with its anti-like conformation (like AMP2-) fits well into the active site of the enzyme. (ii) The phosphonate group has an enhanced metal ion affinity because of its increased basicity. (iii) The ether oxygen forms a 5-membered chelate with the neighboring phosphonate and favors thus coordination at the Pα group. Research on ANPs containing a purine residue revealed that the kind and position of the substituent at C2 or C6 has a significant influence on the biological activity. For example, the shift of the (C6)NH2 group in PMEA to the C2 position leads to 9-[2-(phosphonomethoxy)ethyl]-2-aminopurine (PME2AP), an isomer with only a moderate antiviral activity. Removal of (C6)NH2 favors N7 coordination, e.g., of Cu2+, whereas the ether O atom binding of Cu2+ in PMEA facilitates N3 coordination via adjacent 5- and 7-membered chelates, giving rise to a Cu(PMEA)cl/O/N3 isomer. If the metal ions (M2+) are M(α,β)-M(γ)-coordinated at a triphosphate chain, transphosphorylation occurs (kinases, etc.), whereas metal ion binding in a M(α)-M(β,γ)-type fashion is relevant for polymerases. It may be noted that with diphosphorylated PMEA, (PMEApp4-), the M(α)-M(β,γ) binding is favored because of the formation of the 5-membered chelate involving the ether O atom (see above). The self-association tendency of purines leads to the formation of dimeric [M2(ATP)]2(OH)- stacks, which occur in low concentration and where one half of the molecule undergoes the dephosphorylation reaction and the other half stabilizes the structure-i.e., acts as the "enzyme" by bridging the two ATPs. In accord herewith, one may enhance the reaction rate by adding AMP2- to the [Cu2(ATP)]2(OH)- solution, as this leads to the formation of mixed stacked Cu3(ATP)(AMP)(OH)- species, in which AMP2- takes over the structuring role, while the other "half" of the molecule undergoes dephosphorylation. It may be added that Cu3(ATP)(PMEA) or better Cu3(ATP)(PMEA)(OH)- is even a more reactive species than Cu3(ATP)(AMP)(OH)-. - The matrix-assisted self-association and its significance for cell organelles with high ATP concentrations is summarized and discussed, as is, e.g., the effect of tryptophanate (Trp-), which leads to the formation of intramolecular stacks in M(ATP)(Trp)3- complexes (formation degree about 75%). Furthermore, it is well-known that in the active-site cavities of enzymes the dielectric constant, compared with bulk water, is reduced; therefore, we have summarized and discussed the effect of a change in solvent polarity on the stability and structure of binary and ternary complexes: Opposite effects on charged O sites and neutral N sites are observed, and this leads to interesting insights.
Collapse
Affiliation(s)
- Astrid Sigel
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland;
| | - Helmut Sigel
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland;
| | - Roland K. O. Sigel
- Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| |
Collapse
|
7
|
Eltoukhy L, Loderer C. A Multi-enzyme Cascade for the Biosynthesis of AICA Ribonucleoside Di- and Triphosphate. Chembiochem 2021; 23:e202100596. [PMID: 34859954 PMCID: PMC9299608 DOI: 10.1002/cbic.202100596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/01/2021] [Indexed: 11/10/2022]
Abstract
AICA (5′‐aminoimidazole‐4‐carboxamide) ribonucleotides with different phosphorylation levels are the pharmaceutically active metabolites of AICA nucleoside‐based drugs. The chemical synthesis of AICA ribonucleotides with defined phosphorylation is challenging and expensive. In this study, we describe two enzymatic cascades to synthesize AICA derivatives with defined phosphorylation levels from the corresponding nucleobase and the co‐substrate phosphoribosyl pyrophosphate. The cascades are composed of an adenine phosphoribosyltransferase from Escherichia coli (EcAPT) and different polyphosphate kinases: polyphosphate kinase from Acinetobacter johnsonii (AjPPK), and polyphosphate kinase from Meiothermus ruber (MrPPK). The role of the EcAPT is to bind the nucleobase to the sugar moiety, while the kinases are responsible for further phosphorylation of the nucleotide to produce the desired phosphorylated AICA ribonucleotide. The selected enzymes were characterized, and conditions were established for two enzymatic cascades. The diphosphorylated AICA ribonucleotide derivative ZDP, synthesized from the cascade EcAPT/AjPPK, was produced with a conversion up to 91 %. The EcAPT/MrPPK cascade yielded ZTP with conversion up to 65 % with ZDP as a side product.
Collapse
Affiliation(s)
- Lobna Eltoukhy
- Chair of Molecular Biotechnology Institute for Microbiology, Technische Universität Dresden, Zellescher Weg 20b, 01217, Dresden, Germany
| | - Christoph Loderer
- Chair of Molecular Biotechnology Institute for Microbiology, Technische Universität Dresden, Zellescher Weg 20b, 01217, Dresden, Germany
| |
Collapse
|
8
|
Liu YC, Hsu CM, Hsiao SY, Hsiao HH. Hepatitis B Virus Infection in Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation. J Pers Med 2021; 11:1108. [PMID: 34834460 DOI: 10.3390/jpm11111108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/20/2021] [Accepted: 10/25/2021] [Indexed: 01/12/2023] Open
Abstract
Considering a steady increase in the number of allogeneic hematopoietic stem cell transplantations (allo-HSCT) worldwide and the significant proportion of the world’s population that has been exposed to hepatitis B virus (HBV) infection, HBV reactivation following allo-HSCT remains an important issue for post-transplant morbidity and mortality. Antiviral prophylaxis can reduce HBV replication, severity of HBV-related hepatitis, and mortality; therefore, identification of patients at risk is crucial. It is recommended that all recipients and donors should be screened for active or prior HBV infection, including HBsAg, antiHBc, and antiHBs. Adoptive immunity transfer from the donor seems to have protective effects against HBV reactivation. Antiviral prophylaxis should be initiated in all HBsAg-positive patients. HBsAg-negative, antiHBc-positive patients remain at risk; therefore, antiviral prophylaxis should be considered if baseline serum HBV DNA is detectable. In HBsAg-negative, antiHBc-positive patients without detectable HBV DNA, close monitoring of viral load with an on-demand therapy is necessary. Entecavir or tenofovir rather than lamivudine are more appropriate for the emergence of lamivudine resistance. The treatment duration remains unclear, with 6- to 12-month therapy after cessation of immunosuppressive therapy commonly recommended. Here we review the updated evidence and recent recommendations regarding HBV reactivation in patients undergoing allo-HSCT for individualized therapy.
Collapse
|
9
|
Madaj R, Gostynski B, Pawlowska R, Chworos A. Tissue-Nonspecific Alkaline Phosphatase (TNAP) as the Enzyme Involved in the Degradation of Nucleotide Analogues in the Ligand Docking and Molecular Dynamics Approaches. Biomolecules 2021; 11:1104. [PMID: 34439771 DOI: 10.3390/biom11081104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/16/2021] [Accepted: 07/20/2021] [Indexed: 11/17/2022] Open
Abstract
Tissue-nonspecific alkaline phosphatase (TNAP) is known to be involved in the degradation of extracellular ATP via the hydrolysis of pyrophosphate (PPi). We investigated, using three different computational methods, namely molecular docking, thermodynamic integration (TI) and conventional molecular dynamics (MD), whether TNAP may also be involved in the utilization of β,γ-modified ATP analogues. For that, we analyzed the interaction of bisphosphonates with this enzyme and evaluated the obtained structures using in silico studies. Complexes formed between pyrophosphate, hypophosphate, imidodiphosphate, methylenediphosphonic acid monothiopyrophosphate, alendronate, pamidronate and zoledronate with TNAP were generated and analyzed based on ligand docking, molecular dynamics and thermodynamic integration. The obtained results indicate that all selected ligands show high affinity toward this enzyme. The forming complexes are stabilized through hydrogen bonds, electrostatic interactions and van der Waals forces. Short- and middle-term molecular dynamics simulations yielded very similar affinity results and confirmed the stability of the protein and its complexes. The results suggest that certain effectors may have a significant impact on the enzyme, changing its properties.
Collapse
|
10
|
Chien M, Anderson TK, Jockusch S, Tao C, Li X, Kumar S, Russo JJ, Kirchdoerfer RN, Ju J. Nucleotide Analogues as Inhibitors of SARS-CoV-2 Polymerase, a Key Drug Target for COVID-19. J Proteome Res 2020; 19:4690-4697. [PMID: 32692185 PMCID: PMC7640960 DOI: 10.1021/acs.jproteome.0c00392] [Citation(s) in RCA: 188] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Indexed: 12/18/2022]
Abstract
SARS-CoV-2 is responsible for the current COVID-19 pandemic. On the basis of our analysis of hepatitis C virus and coronavirus replication, and the molecular structures and activities of viral inhibitors, we previously demonstrated that three nucleotide analogues (the triphosphates of Sofosbuvir, Alovudine, and AZT) inhibit the SARS-CoV RNA-dependent RNA polymerase (RdRp). We also demonstrated that a library of additional nucleotide analogues terminate RNA synthesis catalyzed by the SARS-CoV-2 RdRp, a well-established drug target for COVID-19. Here, we used polymerase extension experiments to demonstrate that the active triphosphate form of Sofosbuvir (an FDA-approved hepatitis C drug) is incorporated by SARS-CoV-2 RdRp and blocks further incorporation. Using the molecular insight gained from the previous studies, we selected the active triphosphate forms of six other antiviral agents, Alovudine, Tenofovir alafenamide, AZT, Abacavir, Lamivudine, and Emtricitabine, for evaluation as inhibitors of the SARS-CoV-2 RdRp and demonstrated the ability of these viral polymerase inhibitors to be incorporated by SARS-CoV-2 RdRp, where they terminate further polymerase extension with varying efficiency. These results provide a molecular basis for inhibition of the SARS-CoV-2 RdRp by these nucleotide analogues. If sufficient efficacy of some of these FDA-approved drugs in inhibiting viral replication in cell culture is established, they may be explored as potential COVID-19 therapeutics.
Collapse
Affiliation(s)
- Minchen Chien
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - Thomas K. Anderson
- Department of Biochemistry and Institute of Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Steffen Jockusch
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - Chuanjuan Tao
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - Xiaoxu Li
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - Shiv Kumar
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - James J. Russo
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| | - Robert N. Kirchdoerfer
- Department of Biochemistry and Institute of Molecular Virology, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Jingyue Ju
- Center
for Genome Technology and Biomolecular Engineering, Departments of Chemical
Engineering, Pharmacology, and Chemistry, Columbia University, New York, New York 10027, United States
| |
Collapse
|
11
|
Honarmand Ebrahimi K, Rowbotham JS, McCullagh J, James WS. Mechanism of Diol Dehydration by a Promiscuous Radical-SAM Enzyme Homologue of the Antiviral Enzyme Viperin (RSAD2). Chembiochem 2020; 21:1605-1612. [PMID: 31951306 DOI: 10.1002/cbic.201900776] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Indexed: 12/30/2022]
Abstract
3'-Deoxynucleotides are an important class of drugs because they interfere with the metabolism of nucleotides, and their incorporation into DNA or RNA terminates cell division and viral replication. These compounds are generally produced by multi-step chemical synthesis, and an enzyme with the ability to catalyse the removal of the 3'-deoxy group from different nucleotides has yet to be described. Here, using a combination of HPLC, HRMS and NMR spectroscopy, we demonstrate that a thermostable fungal radical S-adenosylmethionine (SAM) enzyme, with similarity to the vertebrate antiviral enzyme viperin (RSAD2), can catalyse the transformation of CTP, UTP and 5-bromo-UTP to their 3'-deoxy-3',4'-didehydro (ddh) analogues. We show that, unlike the fungal enzyme, human viperin only catalyses the transformation of CTP to ddhCTP. Using electron paramagnetic resonance spectroscopy and molecular docking and dynamics simulations in combination with mutagenesis studies, we provide insight into the origin of the unprecedented substrate promiscuity of the enzyme and the mechanism of dehydration of a nucleotide. Our findings highlight the evolution of substrate specificity in a member of the radical-SAM enzymes. We predict that our work will help in using a new class of the radical-SAM enzymes for the biocatalytic synthesis of 3'-deoxy nucleotide/nucleoside analogues.
Collapse
Affiliation(s)
- Kourosh Honarmand Ebrahimi
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, OX1 3TA, Oxford, UK
| | - Jack S Rowbotham
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, OX1 3TA, Oxford, UK
| | - James McCullagh
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, OX1 3TA, Oxford, UK
| | - William S James
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, OX1 3RE, Oxford, UK
| |
Collapse
|
12
|
Ghozy S, Nam NH, Radwan I, Karimzadeh S, Tieu TM, Hashan MR, Abbas AS, Eid PS, Vuong NL, Khang NV, Elgabalawy E, Sayed AK, Hoa PTL, Huy NT. Therapeutic efficacy of hepatitis B virus vaccine in treatment of chronic HBV infections: A systematic review and meta-analysis. Rev Med Virol 2019; 30:e2089. [PMID: 31811678 DOI: 10.1002/rmv.2089] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 12/13/2022]
Abstract
There is a need for improved treatment of patients with chronic hepatitis B (CHB). We reviewed the literature to explore the efficacy of HB vaccines alone or in combination therapy (CT) with antiviral drugs in CHB patients and to meta-analyze data from randomized controlled trials. We conducted a systematic search in ten databases. All studies investigating the efficacy of HBV vaccine in HBV infected patients were included with no restrictions. Among 1359 studies initially identified, 23 studies (n = 1956 patients) were included for the final analysis. CT showed a significant reduction of HBV DNA compared with analogue monotherapy (AM) at the 12-month follow-up period (odds ratio (OR) = 2.835, 95% confidence interval (CI) [1.275, 6.306], p = .011). Additionally, CT also remarkably induce HbsAg loss in comparison with AM (OR = 11.736, 95% CI [1.841, 74.794], p = .009). Our pooled data revealed no difference between treatment and control regarding alanine aminotransferase normalization, HBeAg seroconversion, and HBeAg disappearance. In addition, CT using vaccine and NAs resulted in a statistically significant higher incidence of adverse effects than AM. The therapeutic effects of combination therapy for patients with CHB were encouraging, but future studies need to investigate all possible treatment combinations and assess their cost-effectiveness.
Collapse
Affiliation(s)
- Sherief Ghozy
- Neurosurgery Department, El Sheikh Zayed Specialized Hospital, Giza, Egypt.,Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan
| | - Nguyen Hai Nam
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Department of General Surgery, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Ibrahim Radwan
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Sedighe Karimzadeh
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Thuan Minh Tieu
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada
| | - Mohammad Rashidul Hashan
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Respiratory and Enteric Infections Department, Infectious Disease Division, International Centre for Diarrheal Disease and Research, Dhaka, Bangladesh
| | - Alzhraa Salah Abbas
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Department of Anesthesia, Al-Ahrar Teaching Hospital, Zagazig, Egypt
| | - Peter Samuel Eid
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Nguyen Lam Vuong
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Department of Medical Statistics and Informatics, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Nguyen Vinh Khang
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Department of Neurology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Eman Elgabalawy
- Online Research Club (http://www.onlineresearchclub.org), Nagasaki, Japan.,Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | | | - Pham Thi Le Hoa
- Department of Infectious Diseases, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Nguyen Tien Huy
- Evidence Based Medicine Research Group, Ton Duc Thang University, Ho Chi Minh City, Vietnam.,Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.,Department of Clinical Product Development, Institute of Tropical Medicine (NEKKEN), School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
| |
Collapse
|
13
|
Duan BW, Tian LT, Lin DD, Zhang J, Guo QL, Wu JS, Zeng DB, Lu SC. Long-term consequences of stopping HBIG and/or nucleotide analogues in liver transplant recipients administered hepatitis B vaccination to prevent HBV reinfection. J Viral Hepat 2019; 26 Suppl 1:85-89. [PMID: 31380589 DOI: 10.1111/jvh.13164] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 05/15/2019] [Indexed: 01/16/2023]
Abstract
BACKGROUND The long-term administration of nucleotide analogues (NAs) and hepatitis B immune globulin (HBIG) comprises standard prophylaxis for patients with hepatitis B virus (HBV)-related liver diseases to prevent HBV reinfection after liver transplantation (LT). However, prolonging the prophylaxis strategy involves safety issues, such as the development of escape mutations and/or emerging resistant strains, and is also associated with high costs; further, it remains unclear how long prophylactic treatment should be continued. METHOD Liver transplantation recipients responding to hepatitis B vaccination due to HBV-related liver diseases were retrospectively analysed after stopping HBIG and/or NAs, administered to prevent HBV reinfection, after long-term follow-up. The safety and effectiveness of the strategy were then evaluated for these responders. RESULT Seventy-eight responders were enrolled. All responders discontinued HBIG, among which 36 stopped both HBIG and NAs. During follow-up, four recipients experienced HBV reinfection, which was associated with HBV escape mutations, after the withdrawal of both HBIG and NAs. No death or graft loss occurred in recipients during the follow-up period. CONCLUSION A careful withdrawal of HBIG and/or NAs is feasible and safe for responders to hepatitis B vaccination receiving transplants for HBV-related liver diseases.
Collapse
Affiliation(s)
- Bin-Wei Duan
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Lan-Tian Tian
- Department of Hepatopancreatobiliary Surgery, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Dong-Dong Lin
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Jing Zhang
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Qing-Liang Guo
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Ju-Shan Wu
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Dao-Bing Zeng
- Department of General Surgery, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Shi-Chun Lu
- Department of Hepatobiliary Surgery, The First Medical Center, Chinese PLA General Hospital, Medical School of Chinese PLA, Beijing, China
| |
Collapse
|
14
|
Abstract
Epstein–Barr virus (EBV) is a human γ-herpesvirus that infects up to 95% of the adult population. Primary EBV infection usually occurs during childhood and is generally asymptomatic, though the virus can cause infectious mononucleosis in 35–50% of the cases when infection occurs later in life. EBV infects mainly B-cells and epithelial cells, establishing latency in resting memory B-cells and possibly also in epithelial cells. EBV is recognized as an oncogenic virus but in immunocompetent hosts, EBV reactivation is controlled by the immune response preventing transformation in vivo. Under immunosuppression, regardless of the cause, the immune system can lose control of EBV replication, which may result in the appearance of neoplasms. The primary malignancies related to EBV are B-cell lymphomas and nasopharyngeal carcinoma, which reflects the primary cell targets of viral infection in vivo. Although a number of antivirals were proven to inhibit EBV replication in vitro, they had limited success in the clinic and to date no antiviral drug has been approved for the treatment of EBV infections. We review here the antiviral drugs that have been evaluated in the clinic to treat EBV infections and discuss novel molecules with anti-EBV activity under investigation as well as new strategies to treat EBV-related diseases.
Collapse
|
15
|
Abstract
OBJECTIVE To assess the benefits of long-term nucleos(t)ide analogue (NA) therapy in reducing the severity and progression of liver disease in treatment-naïve patients with chronic hepatitis B (CHB). SCOPE As complications of CHB, such as hepatic decompensation and hepatocellular carcinoma (HCC), take a long time to develop in patients with less advanced disease, the long-term benefits of NA therapy in such patients are more difficult to prove than short- or medium-term benefits. Thus, the recent literature was reviewed to evaluate the impact of NA therapy on the long-term outcomes of treatment-naïve CHB patients. METHODS A literature search of the MEDLINE/PubMed database was undertaken to identify studies published since 2010 of the long-term use of NAs with high potency and low drug resistance profiles in treatment-naïve CHB patients. A total of 22 studies were identified, many of which were retrospective analyses or case-control studies, as well as three meta-analyses and one systematic review. RESULTS Analysis of the retrieved studies showed that long-term NA therapy in treatment-naïve CHB patients did prevent or delay the occurrence of complications, including hepatic decompensation, HCC, and liver-related death, in comparison with no treatment. However, it did not completely eliminate the risk of these complications, particularly in those with cirrhosis. Although long-term NA therapy improved the clinical status of patients with decompensated cirrhosis, the risk of cirrhotic complications including HCC, liver transplantation, and liver-related mortality remained significant in comparison with those with compensated cirrhosis. CONCLUSIONS Long-term administration is generally advised in all CHB patients treated with NAs because of the high rates of virological and clinical relapse after stopping therapy. The findings of this analysis lend support to the choice of highly potent agents with a low drug resistance profile to maximize viral suppression in CHB patients and halt or delay progression to end-stage liver disease.
Collapse
Affiliation(s)
- Lai Wei
- a Peking University People's Hospital, Peking Hepatology Institute , Beijing
| | | |
Collapse
|
16
|
Gowda ASP, Lee M, Spratt TE. N 2 -Substituted 2'-Deoxyguanosine Triphosphate Derivatives as Selective Substrates for Human DNA Polymerase κ. Angew Chem Int Ed Engl 2017; 56:2628-2631. [PMID: 28140505 DOI: 10.1002/anie.201611607] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/12/2017] [Indexed: 11/09/2022]
Abstract
N2 -Alkyl-2'-deoxyguanosine triphosphate (N2 -alkyl-dGTP) derivatives with methyl, butyl, benzyl, or 4-ethynylbenzyl substituents were prepared and tested as substrates for human DNA polymerases. N2 -Benzyl-dGTP was equal to dGTP as a substrate for DNA polymerase κ (pol κ), but was a poor substrate for pols β, δ, η, ι, or ν. In vivo reactivity was evaluated through incubation of N2 -4-ethynylbenzyl-dG with wild-type and pol κ deficient mouse embryonic fibroblasts. CuAAC reaction with 5(6)-FAM-azide demonstrated that only cells containing pol κ were able to incorporate N2 -4-ethynylbenzyl-dG into the nucleus. This is the first instance of a Y-family-polymerase-specific dNTP, and this method could be used to probe the activity of pol κ in vivo.
Collapse
Affiliation(s)
- A S Prakasha Gowda
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, 500 University Dr., Hershey, PA, 17033, USA
| | - Marietta Lee
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, NY, 10595, USA
| | - Thomas E Spratt
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, 500 University Dr., Hershey, PA, 17033, USA
| |
Collapse
|
17
|
Zhao B, Zhang HY, Xie GJ, Liu HM, Chen Q, Li RF, You JP, Yang S, Mao Q, Zhang XQ. Evaluation of the efficacy of steroid therapy on acute liver failure. Exp Ther Med 2016; 12:3121-3129. [PMID: 27882127 DOI: 10.3892/etm.2016.3720] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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: 05/09/2015] [Accepted: 07/22/2016] [Indexed: 02/06/2023] Open
Abstract
The effects of corticosteroids in the treatment of patients with acute or subacute liver failure (ALF or SALF) are controversial. The aims of the present study were to evaluate the efficacy of corticosteroids in improving spontaneous survival (SS) rate in patients with ALF and SALF, and to determine the groups with the highest rates of response to, and the most effective timing of, corticosteroid administration. A retrospective analysis was performed of all patients with ALF and SALF who were hospitalized in the Department of Infectious Diseases, Southwest Hospital, Chongqing, China from 2000-2012. The most common result of this was SS. A total of 238 patients were studied, including 73 patients with ALF (n=34 steroids, n=39 no steroids) and 165 patients with SALF (n=21 steroids, n=144 no steroids). Corticosteroids improved rates of SS in patients with liver failure (steroids vs. no steroids, 38.2 vs. 20.2%; P=0.011), including patients with ALF (steroids vs. no steroids, 29.4 vs. 5.1%; P=0.013) and with SALF (steroids vs. no steroids, 52.4 vs. 24.3%; P=0.013), patients with viruses (steroids vs. no steroids, 32.4 vs. 14.1%; P=0.042) and patients without viruses (steroids vs. no steroids, 50.0 vs. 24.1%; P=0.043). SS rates were extremely low for patients with coma grade 4 or Model for End-stage Liver Disease (MELD) scores ≥35 (2.2 vs. 11.8%; P=0.180). A significantly improved rate of SS associated with steroid use was observed among patients who had alanine aminotransferase (ALT) levels ≥30 × the upper limit of normal and coma grade <4 and MELD scores <35 (65.0 vs. 17.4%; P=0.002). SS associated with steroid use was significantly higher in patients with an illness duration ≤2 weeks compared with patients with an illness duration >2 weeks (51.4 vs. 15.0%; P=0.010). Corticosteroids improved the prognosis of patients with ALF and SALF. The highest rates of response were observed in patients with a lower MELD score and coma grade but who had extremely high ALT levels. The most effective treatment time was within 2 weeks of the onset of symptoms.
Collapse
Affiliation(s)
- Bo Zhao
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Hui-Yan Zhang
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Gui-Juan Xie
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Hui-Min Liu
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Qing Chen
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Rui-Feng Li
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Jian-Ping You
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Sha Yang
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Qing Mao
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| | - Xu-Qing Zhang
- Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038, P.R. China
| |
Collapse
|
18
|
Abstract
Old tricks, new dog: CRISPR/Cas9 is a powerful tool for gene editing that requires an endonuclease (Cas9) and RNA strands. It has been shown that chemical modification of the RNA structures, an approach that has been used to improve the efficiency of RNA interference, can also be applied to enhance the activity of CRISPR/Cas9 and reduce its off-target effects.
Collapse
Affiliation(s)
- Alfonso Latorre
- IMDEA Nanociencia & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC), Faraday 9, 28049, Madrid, Spain
| | - Ana Latorre
- IMDEA Nanociencia & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC), Faraday 9, 28049, Madrid, Spain
| | - Álvaro Somoza
- IMDEA Nanociencia & Nanobiotecnología (IMDEA-Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC), Faraday 9, 28049, Madrid, Spain.
| |
Collapse
|
19
|
Kolodziej K, Romanowska J, Stawinski J, Kraszewski A, Sobkowski M. The case of triethylammonium cation loss during purification of certain nucleotide analogues: a cautionary note. Anal Bioanal Chem 2015; 407:1775-80. [PMID: 25542580 PMCID: PMC4329187 DOI: 10.1007/s00216-014-8397-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 11/20/2014] [Accepted: 12/08/2014] [Indexed: 10/25/2022]
Abstract
Nucleotides, their analogues, and other phosphate esters and phosphoramidates often contain the triethylammonium cation as a counterion. We found that this may be lost during chromatographic purification or concentration of solutions, yielding products in acidic forms or containing sub-stoichiometric amounts of the counterion. This in turn may be detrimental, e.g., due to possible decomposition of a compound or inaccurate sample preparation. Correlations between the structure of studied compounds and their susceptibility for cation loss were analyzed. Modifications in preparative techniques were developed to obtain the studied compounds with stoichiometric anion to cation ratios.
Collapse
Affiliation(s)
- Krystian Kolodziej
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Joanna Romanowska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Jacek Stawinski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Adam Kraszewski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | - Michal Sobkowski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| |
Collapse
|
20
|
Sharma N, Hoshika S, Hutter D, Bradley KM, Benner SA. Recombinase-based isothermal amplification of nucleic acids with self-avoiding molecular recognition systems (SAMRS). Chembiochem 2014; 15:2268-74. [PMID: 25209570 PMCID: PMC7162014 DOI: 10.1002/cbic.201402250] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Indexed: 12/27/2022]
Abstract
Recombinase polymerase amplification (RPA) is an isothermal method to amplify nucleic acid sequences without the temperature cycling that classical PCR uses. Instead of using heat to denature the DNA duplex, RPA uses recombination enzymes to swap single-stranded primers into the duplex DNA product; these are then extended using a strand-displacing polymerase to complete the cycle. Because RPA runs at low temperatures, it never forces the system to recreate base-pairs following Watson-Crick rules, and therefore it produces undesired products that impede the amplification of the desired product, complicating downstream analysis. Herein, we show that most of these undesired side products can be avoided if the primers contain components of a self-avoiding molecular recognition system (SAMRS). Given the precision that is necessary in the recombination systems for them to function biologically, it is surprising that they accept SAMRS. SAMRS-RPA is expected to be a powerful tool within the range of amplification techniques available to scientists.
Collapse
Affiliation(s)
- Nidhi Sharma
- Foundation for Applied Molecular Evolution, P.O. Box 13174, Gainesville FL 32604 (USA)
| | | | | | | | | |
Collapse
|
21
|
Stornetta A, Angelov T, Guengerich FP, Sturla SJ. Incorporation of nucleoside probes opposite O⁶-methylguanine by Sulfolobus solfataricus DNA polymerase Dpo4: importance of hydrogen bonding. Chembiochem 2013; 14:1634-9. [PMID: 23959784 DOI: 10.1002/cbic.201300296] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [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: 05/08/2013] [Indexed: 11/11/2022]
Abstract
O⁶-Methylguanine (O⁶-MeG) is a mutagenic DNA lesion, arising from the action of methylating agents on guanine (G) in DNA. Dpo4, an archaeal low-fidelity Y-family DNA polymerase involved in translesion DNA synthesis (TLS), is a model for studying how human Y-family polymerases bypass DNA adducts. Previous work showed that Dpo4-mediated dTTP incorporation is favored opposite O⁶-MeG rather than opposite G. However, factors influencing the preference of Dpo4 to incorporate dTTP opposite O⁶-MeG are not fully defined. In this study, we investigated the influence of structural features of incoming dNTPs on their enzymatic incorporation opposite O⁶-MeG in a DNA template. To this end, we utilized a new fluorescence-based primer extension assay to evaluate the incorporation efficiency of a panel of synthetic dNTPs opposite G or O⁶-MeG by Dpo4. In single-dNTP primer extension studies, the synthetic dNTPs were preferentially incorporated opposite G, relative to O⁶-MeG. Moreover, pyrimidine-based dNTPs were generally better incorporated than purine-based syn-conformation dNTPs. The results suggest that hydrophobicity of the incoming dNTP appears to have little influence on the process of nucleotide selection by Dpo4, with hydrogen bonding capacity being a major influence. Additionally, modifications at the C2-position of dCTP increase the selectivity for incorporation opposite O⁶-MeG without a significant loss of efficiency.
Collapse
Affiliation(s)
- Alessia Stornetta
- Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, Swiss Federal Institute of Technology Zürich, Schmelzbergstrasse 9, 8092 Zürich (Switzerland)
| | | | | | | |
Collapse
|
22
|
Abstract
The 5-halopyrimidine nucleotides damage DNA upon UV-irradiation or exposure to gamma-radiolysis via the formation of the 2'-deoxyuridin-5-yl sigma-radical. The bromo and iodo derivatives of these molecules are useful tools for probing DNA structure and as therapeutically useful radiosensitizing agents. A series of aryl iodide C-nucleotides were incorporated into synthetic oligonucleotides and exposed to UV-irradiation and gamma-radiolysis. The strand damage produced upon irradiation of DNA containing these molecules is consistent with the generation of highly reactive sigma-radicals. Direct stand breaks and alkali-labile lesions are formed at the nucleotide analogue and flanking nucleotides. The distribution of lesion type and location varies depending upon the position of the aryl ring that is iodinated. Unlike 5-halopyrimidine nucleotides, the aryl iodides produce interstrand cross-links in duplex regions of DNA when exposed to gamma-radiolysis or UV-irradiation. Quenching studies suggest that cross-links are produced by gamma-radiolysis via capture of a solvated electron, and subsequent fragmentation to the sigma-radical. These observations suggest that aryl iodide C-nucleotide analogues may be useful as probes for excess electron transfer and radiosensitizing agents.
Collapse
Affiliation(s)
- Hui Ding
- Department of Chemistry, Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, USA
| | | |
Collapse
|
23
|
Abstract
UNLABELLED In patients with hepatitis B e antigen-negative chronic hepatitis B, adefovir dipivoxil administration selects variants bearing reverse transcriptase rtN236T and/or rtA181V/T substitutions in 29% of cases after 5 years. The aim of this study was to characterize the dynamics of adefovir-resistant variant populations during adefovir monotherapy in order to better understand the molecular mechanisms underlying hepatitis B virus resistance to this class of nucleotide analogues. Patients included in a 240-week clinical trial of adefovir monotherapy who developed adefovir resistance-associated substitutions were studied. The dynamics of hepatitis B virus populations were analyzed over time, after generating nearly 4,000 full-length reverse transcriptase sequences, and compared with the replication kinetics of the virus during therapy. Whatever the viral kinetics pattern, adefovir resistance was characterized by exclusive detection of a dominant wild-type, adefovir-sensitive variant population at baseline and late and gradual selection by adefovir of several coexisting resistant viral populations, defined by the presence of amino acid substitutions at position rt236, position rt181, or both. The gain in fitness of one or the other of these resistant populations during adefovir administration was never associated with the selection of additional amino acid substitutions in the reverse transcriptase. CONCLUSION Our results suggest that adefovir administration selects poorly fit preexisting or emerging viral populations with low-level adefovir resistance, which subsequently compete to fill the replication space. Viral kinetics depends on the initial virological response to adefovir. Lamivudine add-on restores some antiviral efficacy, but adefovir-resistant variants remain predominant. Whether these adefovir resistance-associated substitutions may confer cross-resistance to tenofovir in vivo will need to be determined.
Collapse
Affiliation(s)
- Coralie Pallier
- Centre de référence français des hépatites B, C et delta
AP-HPHôpital Henri MondorUniversité Paris XII Val de MarneDépartement de virologie Créteil,FR,IMRB, Institut Mondor de recherche biomédicale
INSERM : U841Université Paris XII Val de MarneHôpital Henri Mondor 51, av du mal de lattre de tassigny 94010 CRETEIL CEDEX,FR
| | - Christophe Rodriguez
- Centre de référence français des hépatites B, C et delta
AP-HPHôpital Henri MondorUniversité Paris XII Val de MarneDépartement de virologie Créteil,FR,IMRB, Institut Mondor de recherche biomédicale
INSERM : U841Université Paris XII Val de MarneHôpital Henri Mondor 51, av du mal de lattre de tassigny 94010 CRETEIL CEDEX,FR
| | - Rozenn Brillet
- Centre de référence français des hépatites B, C et delta
AP-HPHôpital Henri MondorUniversité Paris XII Val de MarneDépartement de virologie Créteil,FR,IMRB, Institut Mondor de recherche biomédicale
INSERM : U841Université Paris XII Val de MarneHôpital Henri Mondor 51, av du mal de lattre de tassigny 94010 CRETEIL CEDEX,FR
| | - Patrice Nordmann
- Service de bactériologie et virologie
AP-HPHôpital BicêtreUniversité Paris Sud - Paris XILe Kremlin-Bicêtre,FR
| | - Christophe Hézode
- Centre de référence français des hépatites B, C et delta
AP-HPHôpital Henri MondorUniversité Paris XII Val de MarneDépartement de virologie Créteil,FR,IMRB, Institut Mondor de recherche biomédicale
INSERM : U841Université Paris XII Val de MarneHôpital Henri Mondor 51, av du mal de lattre de tassigny 94010 CRETEIL CEDEX,FR,Department of hepatology and gastroenterologyHôpital Henri Mondor, Université Paris 12Creteil,FR
| | - Jean-Michel Pawlotsky
- Centre de référence français des hépatites B, C et delta
AP-HPHôpital Henri MondorUniversité Paris XII Val de MarneDépartement de virologie Créteil,FR,IMRB, Institut Mondor de recherche biomédicale
INSERM : U841Université Paris XII Val de MarneHôpital Henri Mondor 51, av du mal de lattre de tassigny 94010 CRETEIL CEDEX,FR,* Correspondence should be adressed to: Jean-Michel Pawlotsky
| |
Collapse
|