Structure-Reactivity Relationships on Substrates and Inhibitors of the Lysine Deacylase Sirtuin 2 from Schistosoma Mansoni (SmSirt2)

Author(s):  
Daria Monaldi ◽  
Dante Rotili ◽  
Julien Lancelot ◽  
Martin Marek ◽  
Alessia Lucidi ◽  
...  

The standard drug for treatment of the neglected disease Schistosomiasis is Praziquantel, and the possible emergence of resistance to this treatment makes the research on novel therapeutic agents necessary and urgent. To this end, the targeting of <i>Schistosoma mansoni </i>epigenetic enzymes, which regulate the parasitic life cycle, emerged as promising approach. Due to strong effects of human Sirtuin inhibitors on parasite survival and reproduction, <i>Schistosoma </i>sirtuins were postulated as potential therapeutic targets. <i>In vitro</i> testing of synthetic substrates of <i>Sm</i>Sirt2 and kinetic experiments on a myristoylated peptide newly demonstrated lysine long chain deacylation as an intrinsic <i>Sm</i>Sirt2 activity in addition to the known deacetylation. Focused <i>in vitro</i> screening of the GSK Kinetobox library and structure-activity relationships (SAR) of identified hits, led to the first <i>Sm</i>Sirt2 inhibitors with activity in the low micromolar range. Several <i>Sm</i>Sirt2 inhibitors showed potency against both larval schistosomes (viability) and adult worms (pairing, egg laying) in culture without general toxicity to human cancer cells. <br>

Author(s):  
Daria Monaldi ◽  
Dante Rotili ◽  
Julien Lancelot ◽  
Martin Marek ◽  
Nathalie Wössner ◽  
...  

The only drug for treatment of Schistosomiasis is Praziquantel, and the possible emergence of resistance makes research on novel therapeutic agents necessary. Targeting of Schistosoma mansoni epigenetic enzymes, which regulate the parasitic life cycle, emerged as promising approach. Due to the strong effects of human Sirtuin inhibitors on parasite survival and reproduction, Schistosoma sirtuins were postulated as therapeutic targets. In vitro testing of synthetic substrates of S. mansoni Sirtuin 2 (SmSirt2) and kinetic experiments on a myristoylated peptide demonstrated lysine long chain deacylation as an intrinsic SmSirt2 activity for the first time. Focused in vitro screening of the GSK Kinetobox library and structure-activity relationships (SAR) of identified hits, led to the first SmSirt2 inhibitors with activity in the low micromolar range. Several SmSirt2 inhibitors showed potency against both larval schistosomes (viability) and adult worms (pairing, egg laying) in culture without general toxicity to human cancer cells.<br>


2019 ◽  
Author(s):  
Daria Monaldi ◽  
Dante Rotili ◽  
Julien Lancelot ◽  
Martin Marek ◽  
Nathalie Wössner ◽  
...  

The only drug for treatment of Schistosomiasis is Praziquantel, and the possible emergence of resistance makes research on novel therapeutic agents necessary. Targeting of Schistosoma mansoni epigenetic enzymes, which regulate the parasitic life cycle, emerged as promising approach. Due to the strong effects of human Sirtuin inhibitors on parasite survival and reproduction, Schistosoma sirtuins were postulated as therapeutic targets. In vitro testing of synthetic substrates of S. mansoni Sirtuin 2 (SmSirt2) and kinetic experiments on a myristoylated peptide demonstrated lysine long chain deacylation as an intrinsic SmSirt2 activity for the first time. Focused in vitro screening of the GSK Kinetobox library and structure-activity relationships (SAR) of identified hits, led to the first SmSirt2 inhibitors with activity in the low micromolar range. Several SmSirt2 inhibitors showed potency against both larval schistosomes (viability) and adult worms (pairing, egg laying) in culture without general toxicity to human cancer cells.<br>


2021 ◽  
Vol 22 (16) ◽  
pp. 8372
Author(s):  
Ana María Zárate ◽  
Christian Espinosa-Bustos ◽  
Simón Guerrero ◽  
Angélica Fierro ◽  
Felipe Oyarzún-Ampuero ◽  
...  

The Smoothened (SMO) receptor is the most druggable target in the Hedgehog (HH) pathway for anticancer compounds. However, SMO antagonists such as vismodegib rapidly develop drug resistance. In this study, new SMO antagonists having the versatile purine ring as a scaffold were designed, synthesised, and biologically tested to provide an insight to their mechanism of action. Compound 4s was the most active and the best inhibitor of cell growth and selectively cytotoxic to cancer cells. 4s induced cell cycle arrest, apoptosis, a reduction in colony formation and downregulation of PTCH and GLI1 expression. BODIPY-cyclopamine displacement assays confirmed 4s is a SMO antagonist. In vivo, 4s strongly inhibited tumour relapse and metastasis of melanoma cells in mice. In vitro, 4s was more efficient than vismodegib to induce apoptosis in human cancer cells and that might be attributed to its dual ability to function as a SMO antagonist and apoptosis inducer.


2021 ◽  
Vol 45 (11) ◽  
pp. 5176-5183
Author(s):  
Ichraf Slimani ◽  
Serap Şahin-Bölükbaşı ◽  
Mustafa Ulu ◽  
Enes Evren ◽  
Nevin Gürbüz ◽  
...  

A series of benzimidazolium salts and their [RhCl(NHC)(COD)] complexes were synthesized. All compounds were screened for in vitro cytotoxic activities against a panel of human cancer cells (HT-29 colon, Ishikawa endometrial, U-87 glioblastoma) using the MTT assay for 48 h incubation time.


1987 ◽  
Author(s):  
G Grignani ◽  
L Pacchiarini ◽  
M Zucchella ◽  
L Dezza ◽  
S C Rizzo

The mechanisms of platelet activation by human tumour cells grown “in vitro” or freshly dissociated from tumour tissues have been investigated.MoCCL human T-lymphoblastic cells cultured “in vitro” induced platelet aggregation through the production of ADP, as evidenced by inhibition of the effect by apyrase. The maximum of ADP production by tumour cells was reached after 1 hour and was 225 p moles/106 cells.On the contrary, platelet aggregation induced by 5637 human bladder carcinoma cells was not inhibited by apyrase, but was abolished by hirudin, indicating the important role of thrombin in this effect.Tumour cells dissociated from 3 breast carcinomas showed a very high platelet aggregating activity, which was not inhibited by hirudin or apyrase, but was abolished by iodoacetic acid, suggesting a role for a cystein-protease in platelet activation.These results confirm that platelets can be activated by tumour cells through different mechanisms; they also suggest that the methods employed to obtain the tumour cells can influence the results, probably because of the different cell populations which are present in the dissociated tumour tissues.Informations obtained with freshly dissociated cells are interesting, because this method has been used seldom so far and because it provides a more physiological approach to the study of the interactions of tumours and platelets.


2011 ◽  
Vol 83 (3) ◽  
pp. 1045-1058 ◽  
Author(s):  
Paulo Michel P. Ferreira ◽  
Davi F. Farias ◽  
Martônio P. Viana ◽  
Terezinha M. Souza ◽  
Ilka M. Vasconcelos ◽  
...  

This study assessed the antiproliferative and cytotoxic potential against tumor lines of ethanolic seed extracts of 21 plant species belonging to different families from Northeastern Brazil. In addition, some underlying mechanisms involved in this cytotoxicity were also investigated. Among the 21 extracts tested, the MTT assay after 72 h of incubation demonstrated that only the ethanolic extract obtained from Myracrodruon urundeuva seeds (EEMUS), which has steroids, alkaloids and phenols, showed in vitro cytotoxic activity against human cancer cells, being 2-fold more active on leukemia HL-60 line [IC50 value of 12.5 (9.5-16.7) μg/mL] than on glioblastoma SF-295 [IC50 of 25.1 (17.3-36.3) μg/mL] and Sarcoma 180 cells [IC50 of 38.1 (33.5-43.4) μg/mL]. After 72h exposure, flow cytometric and morphological analyses of HL-60-treated cells showed that EEMUS caused decrease in cell number, volume and viability as well as internucleosomal DNA fragmentation in a dose-dependent way, suggesting that the EEMUS triggers apoptotic pathways of cell death.


2015 ◽  
Vol 3 (3) ◽  
pp. 457-468 ◽  
Author(s):  
Ishita Matai ◽  
Abhay Sachdev ◽  
P. Gopinath

Herein, we report the development of a poly(amidoamine) (PAMAM) dendrimer based multicomponent therapeutic agent forin vitrocancer therapy applications.


Sign in / Sign up

Export Citation Format

Share Document