Influence of P-glycoprotein expression on in vitro cytotoxicity and in vivo antitumour activity of the novel pyrrolobenzodiazepine dimer SJG-136

2005 ◽  
Vol 41 (12) ◽  
pp. 1811-1818 ◽  
Author(s):  
S.M. Guichard ◽  
J.S. Macpherson ◽  
D.E. Thurston ◽  
D.I. Jodrell
2012 ◽  
Vol 32 (6) ◽  
pp. 559-566 ◽  
Author(s):  
Yan Xu ◽  
Feng Zhi ◽  
Guangming Xu ◽  
Xiaolei Tang ◽  
Sheng Lu ◽  
...  

MDR (multidrug-resistance) represents a major obstacle to successful cancer chemotherapy and is usually accomplished by overexpression of P-gp (P-glycoprotein). Much effort has been devoted to developing P-gp inhibitors to modulate MDR. However, none of the inhibitors on the market have been successful. 1416 [1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (phenoprolamine hydrochloride)] is a new VER (verapamil) analogue with a higher IC50 for blocking calcium channel currents than VER. In the present paper, we examined the inhibition effect of 1416 on P-gp both in vitro and in vivo. 1416 significantly enhanced cytotoxicity of VBL (vinblastine) in P-gp-overexpressed human multidrug-resistant K562/ADM (adriamycin) and KBV cells, but had no such effect on the parent K562 and KB cells. The MDR-modulating function of 1416 was further confirmed by increasing intracellular Rh123 (rhodanmine123) content in MDR cells. Human K562/ADM xenograft-nude mice model verified that 1416 potentiates the antitumour activity of VBL in vivo. RT-PCR (reverse transcriptase-PCR) and FACS analysis demonstrated that the expression of MDR1/P-gp was not affected by 1416 treatment. All these observations suggest that 1416 could be a promising agent for overcoming MDR in cancer chemotherapy.


2007 ◽  
Vol 5 (4) ◽  
pp. 313-314 ◽  
Author(s):  
S. Hammer ◽  
N. Arnold ◽  
F. Hilpert ◽  
K. Bräutigam ◽  
A. Sommer ◽  
...  

1984 ◽  
Vol 62 (4) ◽  
pp. 396-402 ◽  
Author(s):  
Douglas J. Kohlsmith ◽  
Keith Vaughan ◽  
Stephen J. Luner

In vitro cytotoxicity of a series of antitumour triazenes towards the M21 melanoma cell line has been studied. Dimethyltriazenes are structural analogues of 5-(3,3-dimethyl-1-triazeno-)imidazole-4-carboxamide (Dacarbazine) and are inactive, which is consistent with the requirement for metabolic activation. Monomethyltriazenes and hydroxymethyltriazenes, the proposed metabolites of the dimethyltriazenes, are cytotoxic to the M21 cell line. A new series of 4-hydroxy-1,2,3-benzotriazines has been tested for in vitro cytotoxicity. A series of monoalkyltriazenes (Ar∙N=N∙NHR) has been tested for antitumour activity against the P388 lymphoma in vivo. Only monomethyltriazenes had significant antitumour activity, which supports the hypothesis that the monomethyltriazene is the active metabolite of the antitumour dimethyltriazenes. The activity of monomethyltriazenes in vivo is correlated with the chemical stability and t1/2 measurements in pH 7.5 phosphate buffer.


1993 ◽  
Vol 31 (4) ◽  
pp. 289-294 ◽  
Author(s):  
H. P. Hofs ◽  
D. J. T. Wagener ◽  
V. de Valk-Bakker ◽  
H. van Rennes ◽  
A. J. van Zeist ◽  
...  

2018 ◽  
Vol 15 (4) ◽  
pp. 564-575 ◽  
Author(s):  
Arehalli S. Manjappa ◽  
Popat S. Kumbhar ◽  
Prajakta S. Khopade ◽  
Ajit B. Patil ◽  
John I. Disouza

2020 ◽  
Vol 17 ◽  
Author(s):  
Akhlesh Kumar Jain ◽  
Hitesh Sahu ◽  
Keerti Mishra ◽  
Suresh Thareja

Aim: To design D-Mannose conjugated 5-Fluorouracil (5-FU) loaded Jackfruit seed starch nanoparticles (JFSSNPs) for site specific delivery. Background: Liver cancer is the third leading cause of death in world and fifth most often diagnosed cancer is the major global threat to public health. Treatment of liver cancer with conventional method bears several side effects, thus to undertake these side effects as a formulation challenge, it is necessary to develop novel target specific drug delivery system for the effective and better localization of drug into the proximity of target with restricting the movement of drug in normal tissues. Objective: To optimize and characterize the developed D-Mannose conjugated 5-Fluorouracil (5-FU) loaded Jackfruit seed starch nanoparticles (JFSSNPs) for effective treatment of liver cancer. Materials and methods: 5-FU loaded JFSSNPs were prepared and optimized formulation had higher encapsulation efficiency were conjugated with D-Mannose. These formulations were characterized for size, morphology, zeta potential, X-Ray Diffraction, and Differential Scanning Calorimetry. Potential of NPs were studied using in vitro cytotoxicity assay, in vivo kinetic studies and bio-distribution studies. Result and discussion: 5-Fluorouracil loaded NPs had particle size between 336 to 802nm with drug entrapment efficiency was between 64.2 to 82.3%. In XRD analysis, 5-FU peak was diminished in the diffractogram, which could be attributed to the successful incorporation of drug in amorphous form. DSC study suggests there was no physical interaction between 5- FU and Polymer. NPs showed sustained in vitro 5-FU release up to 2 hours. In vivo, mannose conjugated NPs prolonged the plasma level of 5-FU and assist selective accumulation of 5-FU in the liver (vs other organs spleen, kidney, lungs and heart) compared to unconjugated one and plain drug. Conclusion: In vivo, bio-distribution and plasma profile studies resulted in significantly higher concentration of 5- Fluorouracil liver suggesting that these carriers are efficient, viable, and targeted carrier of 5-FU treatment of liver cancer.


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 22 (1) ◽  
Author(s):  
Olanrewaju Ayodeji Durojaye ◽  
Nkwachukwu Oziamara Okoro ◽  
Arome Solomon Odiba

Abstract Background The novel coronavirus SARS-CoV-2 is currently a global threat to health and economies. Therapeutics and vaccines are in rapid development; however, none of these therapeutics are considered as absolute cure, and the potential to mutate makes it necessary to find therapeutics that target a highly conserved regions of the viral structure. Results In this study, we characterized an essential but poorly understood coronavirus accessory X4 protein, a core and stable component of the SARS-CoV family. Sequence analysis shows a conserved ~ 90% identity between the SARS-CoV-2 and previously characterized X4 protein in the database. QMEAN Z score of the model protein shows a value of around 0.5, within the acceptable range 0–1. A MolProbity score of 2.96 was obtained for the model protein and indicates a good quality model. The model has Ramachandran values of φ = − 57o and ψ = − 47o for α-helices and values of φ = − 130o and ψ = + 140o for twisted sheets. Conclusions The protein data obtained from this study provides robust information for further in vitro and in vivo experiment, targeted at devising therapeutics against the virus. Phylogenetic analysis further supports previous evidence that the SARS-CoV-2 is positioned with the SL-CoVZC45, BtRs-BetaCoV/YN2018B and the RS4231 Bat SARS-like corona viruses.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Bing Yuan ◽  
Jiaojiao Liu ◽  
Zhixiong Deng ◽  
Lin Wei ◽  
Wenwen Li ◽  
...  

AbstractAddressing the devastating threat of drug-resistant pathogens requires the discovery of new antibiotics with advanced action mechanisms and/or novel strategies for drug design. Herein, from a biophysical perspective, we design a class of synthetic antibacterial complexes with specialized architectures based on melittin (Mel), a natural antimicrobial peptide, and poly(ethylene glycol) (PEG), a clinically available agent, as building blocks that show potent and architecture-modulated antibacterial activity. Among the complexes, the flexibly linear complex consisting of one Mel terminally connected with a long-chained PEG (e.g., PEG12k–1*Mel) shows the most pronounced improvement in performance compared with pristine Mel, with up to 500% improvement in antimicrobial efficiency, excellent in vitro activity against multidrug-resistant pathogens (over a range of minimal inhibitory concentrations of 2–32 µg mL−1), a 68% decrease in in vitro cytotoxicity, and a 57% decrease in in vivo acute toxicity. A lipid-specific mode of action in membrane recognition and an accelerated “channel” effect in perforating the bacterial membrane of the complex are described. Our results introduce a new way to design highly efficient and low-toxicity antimicrobial drugs based on architectural modulations with clinically available agents.


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