Effect of etoposide on grass pea DNA topoisomerase II: an in silico, in vivo, and in vitro assessments

Abstract Background Etoposide is one of the most potential anti-cancerous drugs that targets topoisomerase II (topoII) and inhibits its activity by ligation with the DNA molecule. Results In silico study confirmed that the etoposide-binding sites of topoII are conserved among the plants and human. The efficacy of the drug on plant system was initially assessed using germinated grass pea (Lathyrus sativus L.) seedlings (in vivo) in relation to radicle length and mitotic index. The callus system (in vitro) was also used to elucidate the effect of etoposide on callus growth kinetics. Furthermore, it was observed that etoposide able to inhibit the division of polyploid cells induced by colchicine treatment (0.5%, 8 h). To determine the molecular interaction, topoII was isolated from young grass pea leaves using polyethylene glycol fractionation and ammonium sulphate precipitation followed by column chromatography on CM-Sephadex (C-25). The plasmid linearization assays by isolated plant topoII in the presence of etoposide significantly revealed the functional similarity of plants and human topoII. Results indicated that the effect of etoposide on plant topoII is significant. Conclusions This study may pave the way to develop a plant-based assay system for screening the topoisomerase targeted anti-cancerous drugs, as it is convenient and cost-effective.

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The in vivo distribution and dynamics of DNA topoisomerase II in Drosophila embryonic nuclei and chromosomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146217 ◽

1993 ◽

Vol 51 ◽

pp. 74-75

Author(s):

Jason R. Swedlow ◽

Neil Osheroff ◽

Tim Karr ◽

John W. Sedat ◽

David A. Agard

Keyword(s):

Topoisomerase Ii ◽

Biochemical Characterization ◽

Developmental Cycle ◽

Dna Topoisomerase Ii ◽

Chromosomal Distribution ◽

Dna Topoisomerase ◽

Ideal System ◽

Dnase Treatment

DNA topoisomerase II is an ATP-dependent double-stranded DNA strand-passing enzyme that is necessary for full condensation of chromosomes and for complete segregation of sister chromatids at mitosis in vivo and in vitro. Biochemical characterization of chromosomes or nuclei after extraction with high-salt or detergents and DNAse treatment showed that topoisomerase II was a major component of this remnant, termed the chromosome scaffold. The scaffold has been hypothesized to be the structural backbone of the chromosome, so the localization of topoisomerase II to die scaffold suggested that the enzyme might play a structural role in the chromosome. However, topoisomerase II has not been studied in nuclei or chromosomes in vivo. We have monitored the chromosomal distribution of topoisomerase II in vivo during mitosis in the Drosophila embryo. This embryo forms a multi-nucleated syncytial blastoderm early in its developmental cycle. During this time, the embryonic nuclei synchronously progress through 13 mitotic cycles, so this is an ideal system to follow nuclear and chromosomal dynamics.

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The C-terminal domain of Saccharomyces cerevisiae DNA topoisomerase II

Molecular and Cellular Biology ◽

10.1128/mcb.14.5.3197-3207.1994 ◽

1994 ◽

Vol 14 (5) ◽

pp. 3197-3207

Author(s):

P R Caron ◽

P Watt ◽

J C Wang

Keyword(s):

Saccharomyces Cerevisiae ◽

Nuclear Localization ◽

Topoisomerase Ii ◽

Dna Topoisomerase Ii ◽

Dna Topoisomerase ◽

Mutant Proteins ◽

Terminal Domain ◽

Catalytically Active

A set of carboxy-terminal deletion mutants of Saccharomyces cerevisiae DNA topoisomerase II were constructed for studying the functions of the carboxyl domain in vitro and in vivo. The wild-type yeast enzyme is a homodimer with 1,429 amino acid residues in each of the two polypeptides; truncation of the C terminus to Ile-1220 has little effect on the function of the enzyme in vitro or in vivo, whereas truncations extending beyond Gln-1138 yield completely inactive proteins. Several mutant enzymes with C termini in between these two residues were found to be catalytically active but unable to complement a top2-4 temperature-sensitive mutation. Immunomicroscopy results suggest that the removal of a nuclear localization signal in the C-terminal domain is likely to contribute to the physiological dysfunction of these proteins; the ability of these mutant proteins to relax supercoiled DNA in vivo shows, however, that at least some of the mutant proteins are present in the nuclei in a catalytically active form. In contrast to the ability of the catalytically active mutant proteins to relax supercoiled intracellular DNA, all mutants that do not complement the temperature-dependent lethality and high frequency of chromosomal nondisjunction of top2-4 were found to lack decatenation activity in vivo. The plausible roles of the DNA topoisomerase II C-terminal domain, in addition to providing a signal for nuclear localization, are discussed in the light of these results.

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THE POTENTIAL OF ROBUSTA COFFEE (COFFEA CANEPHORA) AS A COLORECTAL CANCER THERAPY MODALITY: AN IN SILICO STUDY

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2021.v14i10.43025 ◽

2021 ◽

pp. 83-87

Author(s):

DESSY AGUSTINI ◽

LEO VERNADESLY ◽

DELVIANA ◽

THEODORUS

Keyword(s):

Colorectal Cancer ◽

In Silico ◽

Hydrophobic Interactions ◽

Binding Energies ◽

In Vivo Studies ◽

Discovery Studio ◽

Robusta Coffee ◽

In Silico Study

Objectives: This research aims to determine the efficacy of compounds in robusta coffee against colorectal cancer through the inhibition of the T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) receptor. Methods: This in silico study has been conducted in computing platform from June to August 2021. The selected test compounds would go through the Lipinski rule screening through the SwissADME website and the compounds that met these regulations would be docked to the TIGIT protein using AutoDock Tools and AutoDock Vina. The interactions with the highest binding energies were visualized using BIOVIA Discovery Studio 2020. The test compounds then underwent a toxicity profile analysis on the admetSAR 2.0 website. Results: All test compounds complied with the Lipinski rule. The molecular docking results showed the highest binding energy in kahweol and cafestol (−8.1 kcal/mol) compared to OMC (−7.9 kcal/mol), chlorogenic acid (−7.8 kcal/mol), caffeic acid (−6.3 kcal/mol), caffeine (−6.1 kcal/mol), trigonelline (−5.3 kcal/mol), HMF (−5.1 kcal/mol), furfuryl alcohol (−4.4 kcal/mol), and 5-fluorouracil as the comparator drug (−5.3 kcal/mol). Kahweol, cafestol, and 5-fluorouracil revealed the hydrophobic interactions and hydrogen bonds with amino acid residues in TIGIT. Kahweol and cafestol unveiled minimal toxicity prediction Conclusion: Kahweol and cafestol demonstrated the best results in inhibiting the TIGIT protein which played a role in colorectal cancer. In vitro and in vivo studies are needed to strengthen the findings of this research.

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Bioassays and In Silico Methods in the Identification of Human DNA Topoisomerase IIα Inhibitors

Current Medicinal Chemistry ◽

10.2174/0929867325666180306165725 ◽

2018 ◽

Vol 25 (28) ◽

pp. 3286-3318 ◽

Cited By ~ 7

Author(s):

Kaja Bergant ◽

Matej Janezic ◽

Andrej Perdih

Keyword(s):

In Silico ◽

In Vivo Studies ◽

Topoisomerase Iiα ◽

Dna Topoisomerase ◽

Human Dna ◽

Practical Guidelines ◽

In Silico Methods ◽

Dna Topoisomerase Iiα

Background: The family of DNA topoisomerases comprises a group of enzymes that catalyse the induction of topological changes to DNA. These enzymes play a role in the cell replication machinery and are, therefore, important targets for anticancer drugs - with human DNA topoisomerase IIα being one of the most prominent. Active compounds targeting this enzyme are classified into two groups with diverse mechanisms of action: DNA poisons act by stabilizing a covalent cleavage complex between DNA and the topoisomerase enzyme, transforming it into a cellular toxin, while the second diverse group of catalytic inhibitors, provides novel inhibition avenues for tackling this enzyme due to frequent occurrence of side effects observed during the DNA poison therapy. Methods: Based on a comprehensive literature search we present an overview of available bioassays and in silico methods in the identification of human DNA topoisomerase IIα inhibitors. Results and Conclusion: A comprehensive outline of the available methods and approaches that explore in detail the in vitro mechanistic and functional aspects of the topoisomerase IIα inhibition of both topo IIα inhibitor groups is presented. The utilized in vitro cell-based assays and in vivo studies to further explore the validated topo IIα inhibitors in subsequent preclinical stages of the drug discovery are discussed. The potential of in silico methods in topoisomerase IIα inhibitor discovery is outlined. A list of practical guidelines was compiled to aid new as well experienced researchers in how to optimally approach the design of targeted inhibitors and validation in the preclinical drug development stages.

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Prospects of Wedelolactone as a Chemotherapeutic Agent in Gynecological Cancers; Clue From its In Vitro and In Silico Investigation

Current Computer - Aided Drug Design ◽

10.2174/1573409915666191015113134 ◽

2020 ◽

Vol 16 (4) ◽

pp. 365-375

Author(s):

Sadia Sarwar ◽

Tauqeer Amed ◽

Neelum Gul Qazi ◽

Jun Qing Yu ◽

Fazlul Huq

Keyword(s):

Alkaline Phosphatase ◽

Cell Lines ◽

In Silico ◽

Topoisomerase Ii ◽

Tumor Models ◽

Growth Inhibitory ◽

In Silico Study ◽

Inhibitory Potential ◽

Mcf 7

Background: Identification and development of new drug candidates to be used singly or in combination therapy is critical in anticancer research. In recent years, accumulating evidence encouraged us to investigate the anti-proliferative effects of a small and emerging phytochemical Wedelolactone (WDL) in estrogen-dependent and independent multiple gynecological tumor models. Objective: The aim of this study was to investigate the growth inhibitory effect of WDL on estrogen- dependent and independent gynecological cell lines and to explore its inhibitory potential towards key targets through in silico study. Methods: Cytotoxicity of WDL was investigated in human breast and ovarian cancer cell lines (MCF-7 and SKOV3) through 3-(4,5-Dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) reduction assay. Epigallocatechingallate (EGCG) was used as reference natural compound while cisplatin was taken as a standard clinical agent. Both WDL and EGCG in combination with cisplatin were also evaluated for their combined growth inhibitory potential in MCF-7 cells. WDL was also evaluated in silico against key factors including braf kinases, CDPK, ERα, aromatase, topoisomerase II and dihydrofolate reductase (DHFR) playing pivotal roles in driving multiple tumors. Results and Discussion: The IC50 value of WDL was 25.77 ± 4.82 μM and 33.64 ± 1.45 μM in MCF-7 and SKOV-3 respectively. The binding energy order was as follows; WDL: DHFR >Braf kinases > CDPK; aromatase > topoisomerase II> ERα > NFkB > alkaline phosphatase; EGCG dihydrofolatereductase (DHFR) > aromatase >CDPK > topoisomerase II > braf kinases > alkaline phosphatase > CDPK > ERα > NFkB. Conclusion: We identified WDL as a cytotoxic agent in breast and ovarian tumor models with the potential to inhibit multiple targets in the oncogenic pathway including estrogen receptor ERα, as depicted through its in silico study. Based on our own research findings and from literature evidence, we conclude that further research should be encouraged to investigate different aspects of wedelolactone as an additional agent to be combined with antiestrogen/endocrine therapy.

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Coumarins and Quinolones as Effective Multiple Targeted Agents Versus Covid-19: An in Silico Study

Medicinal Chemistry ◽

10.2174/1573406417666210208223924 ◽

2021 ◽

Vol 17 ◽

Author(s):

Mojgan Nejabat ◽

Razieh Ghodsi ◽

Farzin Hadizadeh

Keyword(s):

Binding Affinity ◽

In Silico ◽

Oral Absorption ◽

Antiviral Agent ◽

In Vivo Studies ◽

Reference Drug ◽

Viral Proteases ◽

In Silico Study

Background: The Covid-19 virus emerged a few months ago in China and infections rapidly escalated into a pandemic. Objective: To date, there is no selective antiviral agent for the management of pathologies associated with covid-19 and the need for an effective agent against it is essential. Method: In this work two home-made databases from synthetic quinolines and coumarins were virtually docked against viral proteases (3CL and PL), human cell surface proteases (TMPRSS2 and furin) and spike proteins (S1 and S2). Chloroquine, a reference drug without a clear mechanism against coronavirus was also docked on mentioned targets and the binding affinities compared with title compounds. Result: The best compounds of synthetic coumarins and quinolines for each target were determined. All compounds against all targets showed binding affinity between -5.80 to -8.99 kcal/mol in comparison with the FDA-approved drug, Chloroquine, with binding affinity of -5.7 to -7.98 kcal/mol. Two compounds, quinoline-1 and coumarin-24, were found to be effective on three targets – S2, TMPRSS2 and furin – simultaneously, with good predicted affinity between -7.54 to -8.85 kcal/mol. In silico ADME studies also confirmed good oral absorption for them. Furthermore, PASS prediction was calculated and coumarin-24 had higher probable activity (Pa) than probable inactivity (Pi) with acceptable protease inhibitory as well as good antiviral activity against Hepatitis C virus (HCV), Human immunodeficiency virus (HIV) and influenza. Conclusion: Quinoline-1 and Coumarin-24 have the potential to be used against Covid-19. Hence these agents could be useful in combating covid-19 infection after further in vitro and in vivo studies.

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