scholarly journals EPCT-17. DEVELOPING EYA PHOSPHATASE INHIBITORS WITH ON-TARGET EFFECTS IN SHH-MEDULLOBLASTOMA

2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i50-i50
Author(s):  
Grace H. Hwang ◽  
David A Scott ◽  
Rosalind A Segal
Keyword(s):  
Pediatric Brain Tumors ◽  
Selective Treatment ◽  
Phosphatase Inhibitors ◽  
Eyes Absent ◽  
Shh Pathway ◽  
Chemical Derivatives ◽  
A Cell ◽  
Cell Inhibition ◽  
New Compounds

Abstract Medulloblastoma, one of the most frequent malignant pediatric brain tumors, encompasses four molecularly and clinically distinct cancers. Sonic hedgehog (SHH)-subtype medulloblastoma constitutes about 30% of medulloblastomas, and therapies targeting the SHH pathway can lead to new highly selective treatment. The haloacid dehalogenase (HAD) phosphatase Eyes Absent 1 (EYA1) is critically involved in the development and progression of SHH-medulloblastoma: Eya1 is highly expressed in SHH-medulloblastomas, and single cell sequencing indicates that Eya1 is a consistent feature that can be detected in every individual cancer cell. Inhibition of EYA1 interrupts SHH pathway signaling. During normal development, EYA1 promotes symmetric division of cerebellar granule cell precursors (GCPs), the cells of origin for SHH-subtype medulloblastoma, and reduced levels of EYA1 decrease medulloblastoma mortality rates in mouse models. Therefore, targeting EYA1 may be a novel therapeutic avenue for these pediatric cancers. Benzarone derivatives have been suggested as allosteric EYA-inhibitors, and benzarone provides a promising platform for chemical derivatives. Here, we develop 60 novel benzarone derivatives and assess their efficacy in inhibiting SHH-medulloblastoma growth through the inhibition of EYA1. Several of the new compounds inhibit EYA1 phosphotyrosine phosphatase activity in a cell-based assay, interrupt SHH pathway, and prevent SHH-medulloblastoma growth in vitro. Our results show that these novel benzarone derivatives are a new promising avenue for developing therapeutics for pediatric SHH-medulloblastoma via inhibition of EYA phosphatases.

scholarly journals Novel Trypanocidal Analogs of 5′-(Methylthio)-Adenosine

2007 ◽  
Vol 52 (1) ◽  
pp. 211-219 ◽  
Author(s):  
Janice R. Sufrin ◽  
Arthur J. Spiess ◽  
Canio J. Marasco ◽  
Donna Rattendi ◽  
Cyrus J. Bacchi
Keyword(s):  
Trypanosoma Brucei ◽  
Clinical Isolate ◽  
In Vitro Cytotoxicity ◽  
Trypanosoma Brucei Rhodesiense ◽  
Absolute Requirement ◽  
A Cell ◽  
Biochemical Mechanisms ◽  
Ongoing Development ◽  
New Compounds

ABSTRACT The purine nucleoside 5′-deoxy-5′-(hydroxyethylthio)-adenosine (HETA) is an analog of the polyamine pathway metabolite 5′-deoxy-5′-(methylthio)-adenosine (MTA). HETA is a lead structure for the ongoing development of selectively targeted trypanocidal agents. Thirteen novel HETA analogs were synthesized and examined for their in vitro trypanocidal activities against bloodstream forms of Trypanosoma brucei brucei LAB 110 EATRO and at least one drug-resistant Trypanosoma brucei rhodesiense clinical isolate. New compounds were also assessed in a cell-free assay for their activities as substrates of trypanosome MTA phosphorylase. The most potent analog in this group was 5′-deoxy-5′-(hydroxyethylthio)-tubercidin, whose in vitro cytotoxicity (50% inhibitory concentration [IC50], 10 nM) is 45 times greater than that of HETA (IC50, 450 nM) against pentamidine-resistant clinical isolate KETRI 269. Structure-activity analyses indicate that the enzymatic cleavage of HETA analogs by trypanosome MTA phosphorylase is not an absolute requirement for trypanocidal activity. This suggests that additional biochemical mechanisms are associated with the trypanocidal effects of HETA and its analogs.

scholarly journals Bupleurum chinense Roots: a Bioactivity-Guided Approach toward Saponin-Type NF-κB Inhibitors

Planta Medica ◽  
2017 ◽  
Vol 83 (14/15) ◽  
pp. 1242-1250 ◽  
Author(s):  
Xin Liu ◽  
Simone Latkolik ◽  
Atanas Atanasov ◽  
Olaf Kunert ◽  
Eva-Maria Pferschy-Wenzig ◽  
...  
Keyword(s):  
Luciferase Reporter ◽  
Luciferase Reporter Gene ◽  
Gene Model ◽  
Synthetic Compound ◽  
Ic50 Values ◽  
A Cell ◽  
Radix Bupleuri ◽  
New Compounds ◽  
First Time

AbstractThe roots of Bupleurum chinense have a long history in traditional medicine to treat infectious diseases and inflammatory disorders. Two major compounds, saikosaponins A and D, were reported to exert potent anti-inflammatory activity by inhibiting NF-κB. In the present study, we isolated new saikosaponin analogues from the roots of B. chinese interfering with NF-κB activity in vitro. The methanol-soluble fraction of the dichloromethane extract of Radix Bupleuri was subjected to activity-guided isolation yielding 18 compounds, including triterpenoids and polyacetylenes. Their structures were determined by spectroscopic methods as saikogenin D (1), prosaikogenin D (2), saikosaponins B2 (3), W (4), B1 (5), Y (6), D (7), A (8), E (9), B4 (10), B3 (11), and T (12), saikodiyne A (13), D (14), E (15) and F (16), falcarindiol (17), and 1-linoleoyl-sn-glycero-3-phosphorylcholine (18). Among them, 4, 15, and 16 are new compounds, whereas 6, previously described as a semi-synthetic compound, is isolated from a natural source for the first time, and 13–17 are the first reports of polyacetylenes from this plant. Nine saponins/triterpenoids were tested for inhibition of NF-κB signaling in a cell-based NF-κB-dependent luciferase reporter gene model in vitro. Five of them (1, 2, 4, 6, and 8) showed strong (> 50%, at 30 µM) NF-κB inhibition, but also varying degrees of cytotoxicity, with compounds 1 and 4 (showing no significant cytotoxicity) presenting IC50 values of 14.0 µM and 14.1 µM in the cell-based assay, respectively.

Synthesis, characterization, and anticancer evaluation of some new N1-(anthraquinon-2-yl) amidrazone derivatives

2018 ◽  
Vol 96 (12) ◽  
pp. 1123-1128 ◽  
Author(s):  
Kamal Sweidan ◽  
Hiba Zalloum ◽  
Dima A. Sabbah ◽  
Ghada Idris ◽  
Khadija Abudosh ◽  
...  
Keyword(s):  
Cell Lines ◽  
Dermal Fibroblasts ◽  
Myelogenous Leukemia ◽  
Cell Viability Assay ◽  
Viability Assay ◽  
Diphenyltetrazolium Bromide ◽  
A Cell ◽  
New Compounds ◽  
Mcf 7

A new series of novel N1-anthraquinon-2-yl amidrazones incorporating N-piperazines and related congeners were synthesized via reaction of the hydrazonoyl chloride derived from 2-qaminoanthraquinone with the appropriate piperazine (secondary amine). Structures of the new compounds were confirmed by a panel of spectroscopic methods including IR, NMR, and MS and by elemental analysis. The antitumor activity of the newly prepared compounds was evaluated in vitro against MCF-7 breast cancer, K562 chronic myelogenous leukemia, and dermal fibroblasts cell lines by means of a cell viability assay using the tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Results revealed that compounds 13a and 13d exhibit the highest inhibitory activity against K562 and MCF-7 cell lines. These two compounds could be considered as promising as potential anticancer drugs.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

Using FRET to Measure the Time it Takes for a Cell to Destroy a Virus

2019 ◽  
Author(s):  
Candace E. Benjamin ◽  
Zhuo Chen ◽  
Olivia Brohlin ◽  
Hamilton Lee ◽  
Stefanie Boyd ◽  
...  
Keyword(s):  
Cellular Uptake ◽  
Rhodamine B ◽  
Virus Like Particle ◽  
A Cell ◽  
Viral Nanoparticles ◽  
The Stability ◽  
Open Question ◽  
Viral Surface ◽  
Fret Pair

<div><div><div><p>The emergence of viral nanotechnology over the preceding two decades has created a number of intellectually captivating possible translational applications; however, the in vitro fate of the viral nanoparticles in cells remains an open question. Herein, we investigate the stability and lifetime of virus-like particle (VLP) Qβ - a representative and popular VLP for several applications - following cellular uptake. By exploiting the available functional handles on the viral surface, we have orthogonally installed the known FRET pair, FITC and Rhodamine B, to gain insight of the particle’s behavior in vitro. Based on these data, we believe VLPs undergo aggregation in addition to the anticipated proteolysis within a few hours of cellular uptake.</p></div></div></div>

Preincubation with Sn-complexes causes intensive intracellular retention of 99mTc in thyroid cells in vitro

2012 ◽  
Vol 51 (05) ◽  
pp. 179-185 ◽  
Author(s):  
M. Wendisch ◽  
D. Aurich ◽  
R. Runge ◽  
R. Freudenberg ◽  
J. Kotzerke ◽  
...  
Keyword(s):  
Cell Model ◽  
Low Energy ◽  
Thyroid Cells ◽  
Low Energy Electrons ◽  
A Cell ◽  
Vitro Model ◽  
Uptake Studies ◽  
Radiobiological Effects ◽  
Radioactivity Retention

SummaryTechnetium radiopharmaceuticals are well established in nuclear medicine. Besides its well-known gamma radiation, 99mTc emits an average of five Auger and internal conversion electrons per decay. The biological toxicity of these low-energy, high-LET (linear energy transfer) emissions is a controversial subject. One aim of this study was to estimate in a cell model how much 99mTc can be present in exposed cells and which radiobiological effects could be estimated in 99mTc-overloaded cells. Methods: Sodium iodine symporter (NIS)- positive thyroid cells were used. 99mTc-uptake studies were performed after preincubation with a non-radioactive (cold) stannous pyro - phosphate kit solution or as a standard 99mTc pyrophosphate kit preparation or with pure pertechnetate solution. Survival curves were analyzed from colony-forming assays. Results: Preincubation with stannous complexes causes irreversible intracellular radioactivity retention of 99mTc and is followed by further pertechnetate influx to an unexpectedly high 99mTc level. The uptake of 99mTc pertechnetate in NIS-positive cells can be modified using stannous pyrophosphate from 3–5% to >80%. The maximum possible cellular uptake of 99mTc was 90 Bq/cell. Compared with nearly pure extracellular irradiation from routine 99mTc complexes, cell survival was reduced by 3–4 orders of magnitude after preincubation with stannous pyrophosphate. Conclusions: Intra cellular 99mTc retention is related to reduced survival, which is most likely mediated by the emission of low-energy electrons. Our findings show that the described experiments constitute a simple and useful in vitro model for radiobiological investigations in a cell model.

Analysis of the Dynamics of the Electric Capacitance of a Cell Monolayer at the Late Stages of Caco-2 cell Differentiation

2019 ◽  
Vol 35 (6) ◽  
pp. 87-90
Author(s):  
S.V. Nikulin ◽  
V.A. Petrov ◽  
D.A. Sakharov
Keyword(s):  
Impedance Spectroscopy ◽  
Cell Monolayer ◽  
Microfluidic Chips ◽  
Russian Science ◽  
Electric Capacitance ◽  
A Cell ◽  
Static Conditions ◽  
Late Stages

The real-time monitoring of electric capacitance (impedance spectroscopy) allowed obtaining evidence that structures which look like intestinal villi can be formed during the cultivation under static conditions as well as during the cultivation in microfluidic chips. It was shown in this work via transcriptome analysis that the Hh signaling pathway is involved in the formation of villus-like structures in vitro, which was previously shown for their formation in vivo. impedance spectroscopy, intestine, villi, electric capacitance, Hh The study was funded by the Russian Science Foundation (Project 16-19-10597).

Nyctanthes Arbor-Tristis and its Role in the Alleviation of Arthritic Pain: A Review

2020 ◽  
Vol 16 (8) ◽  
pp. 1147-1156
Author(s):  
Ruchi Singh ◽  
Syed M. Hasan ◽  
Amit Verma ◽  
Sanjay K. Panda
Keyword(s):  
Research Work ◽  
Plant Distribution ◽  
Pharmacological Activities ◽  
Whole Plant ◽  
Modern Drug ◽  
Active Chemical ◽  
Drug Synthesis ◽  
New Compounds

Background: A plant is a reservoir of potentially useful active chemical entities which act as drugs as well as intermediates for the discovery of newer molecules and provide newer leads for modern drug synthesis. The demand for new compounds in the field of medicine and biotechnology is centuries old and with a rise in chronic diseases and resistance to existing drugs in the field of anti-infective agents, the chemicals obtained from plant sources have been an area of attraction. The whole plant has possessed multiple pharmacological activities. This is scientifically established by in-vivo and in-vitro studies. Methods: Various electronic databases such as PubMed, Science Direct, Scopus and Google were searched to collect the data of the present review. All the collected information is categorized into different sections as per the aim of the paper. Results: Fifty-six research and review papers have been studied and were included in this review article. After a detailed study, we provide a significant description of various phytochemicals present in Nyctanthes arbor-tristis Linn., which is responsible for various pharmacological activities. Twenty of studied articles gives a general introduction and ethnobotanical information about the plant, two papers contained microscopic detail of leaf and fruit. Twenty papers contained information about the phytoconstituents present in different parts of Nyctanthes arbor-tristis plant and fourteen articles reported pharmacological activities like antioxidant, anti-inflammatory, antiarthritic, antimicrobial and immunobiotic activity. Conclusion: This review explores the published research work comprising the ethnobotanical description of the subjected plant, distribution, phytochemical profile, and arthritis-related pharmacological activities.

scholarly journals Microwave-Assisted Synthesis, Characterization, Antimicrobial and Antioxidant Activity of Some New Isatin Derivatives

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
G. Kiran ◽  
T. Maneshwar ◽  
Y. Rajeshwar ◽  
M. Sarangapani
Keyword(s):  
Antioxidant Activity ◽  
Free Radical ◽  
Radical Scavenging ◽  
Microwave Assisted Synthesis ◽  
Stable Free Radical ◽  
Ft Ir ◽  
Antimicrobial And Antioxidant Activity ◽  
New Compounds ◽  
Isatin Derivatives

A series of β-Isatin aldehyde-N,N′-thiocarbohydrazone derivatives were synthesized and assayed for theirin vitroantimicrobial and antioxidant activity. The new compounds were characterized based on spectral (FT-IR, NMR, MS) analyses. All the test compounds possessed a broad spectrum of activity having MIC values rangeing from 12.5 to 400 μg/ml against the tested microorganisms. Among the compounds3e,3jand3nshow highest significant antimicrobial activity. The free radical scavenging effects of the test compounds against stable free radical DPPH (α,α-diphenyl-β-picryl hydrazyl) and H2O2were measured spectrophotometrically. Compounds3j,3n,3l, and3e, respectively, had the most effective antioxidant activity against DPPH and H2O2scavenging activity.

scholarly journals Assessment of SARS-CoV-2 infectivity of upper respiratory specimens from COVID-19 patients by virus isolation using VeroE6/TMPRSS2 cells

2021 ◽  
Vol 8 (1) ◽  
pp. e000830
Author(s):  
Souichi Yamada ◽  
Shuetsu Fukushi ◽  
Hitomi Kinoshita ◽  
Makoto Ohnishi ◽  
Tadaki Suzuki ◽  
...  
Keyword(s):  
Virus Isolation ◽  
Laboratory Diagnostics ◽  
Viral Isolation ◽  
Viral Loads ◽  
A Cell ◽  
Blind Passage ◽  
Upper Respiratory ◽  
Novel Coronavirus ◽  
Respiratory Specimens

BackgroundAn outbreak of novel coronavirus (SARS-CoV-2)-associated respiratory infectious diseases (COVID-19) emerged in 2019 and has spread rapidly in humans around the world. The demonstration of in vitro infectiousness of respiratory specimens is an informative surrogate for SARS-CoV-2 transmission from patients with COVID-19; accordingly, viral isolation assays in cell culture are an important aspect of laboratory diagnostics for COVID-19.MethodsWe developed a simple and rapid protocol for isolating SARS-CoV-2 from respiratory specimens using VeroE6/TMPRSS2 cells, a cell line that is highly susceptible to the virus. We also investigated a correlation between isolation of SARS-CoV-2 and viral load detected by real-time RT-PCR (rRT-PCR) using N2 primer/probe set that has been developed for testing of COVID-19 in Japan.ResultsThe SARS-CoV-2 isolation protocol did not require blind passage of inoculated cells and yielded the results of viral isolation within 7 days after inoculation. Specimens with cycle threshold (Ct) values of <20.2, determined by rRT-PCR, were predicted to be isolation-positive. On the other hand, 6.9% of specimens with Ct values >35 were virus isolation-positive, indicating that low viral loads (high Ct values) in upper respiratory specimens do not always indicate no risk of containing transmissible virus.ConclusionIn combination with rRT-PCR, the SARS-CoV-2 isolation protocol provides a means for assessing the potential risk of transmissible virus in upper respiratory specimens.

Sign in / Sign up

Export Citation Format

Share Document