scholarly journals A New Strategy for Glioblastoma Treatment: In Vitro and In Vivo Preclinical Characterization of Si306, a Pyrazolo[3,4-d]Pyrimidine Dual Src/P-Glycoprotein Inhibitor

Cancers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 848 ◽  
Author(s):  
Anna Lucia Fallacara ◽  
Claudio Zamperini ◽  
Ana Podolski-Renić ◽  
Jelena Dinić ◽  
Tijana Stanković ◽  
...  

Overexpression of P-glycoprotein (P-gp) and other ATP-binding cassette (ABC) transporters in multidrug resistant (MDR) cancer cells is responsible for the reduction of intracellular drug accumulation, thus decreasing the efficacy of chemotherapeutics. P-gp is also found at endothelial cells’ membrane of the blood-brain barrier, where it limits drug delivery to central nervous system (CNS) tumors. We have previously developed a set of pyrazolo[3,4-d]pyrimidines and their prodrugs as novel Src tyrosine kinase inhibitors (TKIs), showing a significant activity against CNS tumors in in vivo. Here we investigated the interaction of the most promising pair of drug/prodrug with P-gp at the cellular level. The tested compounds were found to increase the intracellular accumulation of Rho 123, and to enhance the efficacy of paclitaxel in P-gp overexpressing cells. Encouraging pharmacokinetics properties and tolerability in vivo were also observed. Our findings revealed a novel role of pyrazolo[3,4-d]pyrimidines which may be useful for developing a new effective therapy in MDR cancer treatment, particularly against glioblastoma.

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.


2009 ◽  
Vol 29 (21) ◽  
pp. 5858-5871 ◽  
Author(s):  
Richard Marcotte ◽  
Lixin Zhou ◽  
Harold Kim ◽  
Calvin D. Roskelly ◽  
William J. Muller

ABSTRACT Previous studies have demonstrated that c-Src tyrosine kinase interacts specifically with ErbB2, but not with other members of the epidermal growth factor receptor (EGFR) family. To identify the site of interaction, we recently used a chimeric EGFR/ErbB2 receptor approach to show that c-Src requires the kinase region of ErbB2 for binding. Here, we demonstrate that retention of a conserved amino acid motif surrounding tyrosine 877 (referred to here as EGFRYHAD) is sufficient to confer binding to c-Src. Surprisingly the association of c-Src was not dependent on its SH2 or SH3 domain or on the phosphorylation or kinase activity of the receptor. We further show that the chimeric EGFRs that contain the Y877 motif are transforming in vitro and in vivo following ligand stimulation. Transformation was also partially dependent on sustained activation of Stat3. Finally, we demonstrate that EGFRs with mutations in the catalytic domain, originally identified in lung cancer and conferring increased sensitivity to gefitinib and erlotinib, two EGFR kinase inhibitors, gained the capacity to bind c-Src. Moreover, transformation by these EGFR mutants was inhibited by Src inhibitors regardless of their sensitivities to gefitinib and erlotinib. These observations have important implications for understanding the molecular basis for resistance to EGFR inhibitors and implicate c-Src as a critical signaling molecule in EGFR mutant-induced transformation.


2012 ◽  
Vol 56 (7) ◽  
pp. 3475-3480 ◽  
Author(s):  
Sovitj Pou ◽  
Rolf W. Winter ◽  
Aaron Nilsen ◽  
Jane Xu Kelly ◽  
Yuexin Li ◽  
...  

ABSTRACTSontochin was the original chloroquine replacement drug, arising from research by Hans Andersag 2 years after chloroquine (known as “resochin” at the time) had been shelved due to the mistaken perception that it was too toxic for human use. We were surprised to find that sontochin, i.e., 3-methyl-chloroquine, retains significant activity against chloroquine-resistant strains ofPlasmodium falciparum in vitro. We prepared derivatives of sontochin, “pharmachins,” with alkyl or aryl substituents at the 3 position and with alterations to the 4-position side chain to enhance activity against drug-resistant strains. Modified with an aryl substituent in the 3 position of the 7-chloro-quinoline ring, Pharmachin 203 (PH-203) exhibits low-nanomolar 50% inhibitory concentrations (IC50s) against drug-sensitive and multidrug-resistant strains andin vivoefficacy against patent infections ofPlasmodium yoeliiin mice that is superior to chloroquine. Our findings suggest that novel 3-position aryl pharmachin derivatives have the potential for use in treating drug resistant malaria.


2000 ◽  
Vol 27 (2) ◽  
pp. 135-141 ◽  
Author(s):  
R Bergmann ◽  
P Brust ◽  
M Scheunemann ◽  
H.-J Pietzsch ◽  
S Seifert ◽  
...  

2005 ◽  
Vol 49 (6) ◽  
pp. 2294-2301 ◽  
Author(s):  
Anne J. Lenaerts ◽  
Veronica Gruppo ◽  
Karen S. Marietta ◽  
Christine M. Johnson ◽  
Diane K. Driscoll ◽  
...  

ABSTRACT This study extends earlier reports regarding the in vitro and in vivo efficacies of the nitroimidazopyran PA-824 against Mycobacterium tuberculosis. PA-824 was tested in vitro against a broad panel of multidrug-resistant clinical isolates and was found to be highly active against all isolates (MIC < 1 μg/ml). The activity of PA-824 against M. tuberculosis was also assessed grown under conditions of oxygen depletion. PA-824 showed significant activity at 2, 10, and 50 μg/ml, similar to that of metronidazole, in a dose-dependent manner. In a short-course mouse infection model, the efficacy of PA-824 at 50, 100, and 300 mg/kg of body weight formulated in methylcellulose or cyclodextrin/lecithin after nine oral treatments was compared with those of isoniazid, rifampin, and moxifloxacin. PA-824 at 100 mg/kg in cyclodextrin/lecithin was as active as moxifloxacin at 100 mg/kg and isoniazid at 25 mg/kg and was slightly more active than rifampin at 20 mg/kg. Long-term treatment with PA-824 at 100 mg/kg in cyclodextrin/lecithin reduced the bacterial load below 500 CFU in the lungs and spleen. No significant differences in activity between PA-824 and the other single drug treatments tested (isoniazid at 25 mg/kg, rifampin at 10 mg/kg, gatifloxacin at 100 mg/kg, and moxifloxacin at 100 mg/kg) could be observed. In summary, its good activity in in vivo models, as well as its activity against multidrug-resistant M. tuberculosis and against M. tuberculosis isolates in a potentially latent state, makes PA-824 an attractive drug candidate for the therapy of tuberculosis. These data indicate that there is significant potential for effective oral delivery of PA-824 for the treatment of tuberculosis.


2022 ◽  
Vol 12 ◽  
Author(s):  
Gangyang Wang ◽  
Lingling Cao ◽  
Yafei Jiang ◽  
Tao Zhang ◽  
Hongsheng Wang ◽  
...  

Overexpression of the multidrug resistance (MDR)-related protein P-glycoprotein (PGP1), which actively extrudes chemotherapeutic agents from cells and significantly decreases the efficacy of chemotherapy, is viewed as a major obstacle in osteosarcoma chemotherapy. Anlotinib, a novel tyrosine kinase inhibitor (TKI), has good anti-tumor effects in a variety of solid tumors. However, there are few studies on the mechanism of anlotinib reversing chemotherapy resistance in osteosarcoma. In this study, cellular assays were performed in vitro and in vivo to evaluate the MDR reversal effects of anlotinib on multidrug-resistant osteosarcoma cell lines. Drug efflux and intracellular drug accumulation were measured by flow cytometry. The vanadate-sensitive ATPase activity of PGP1 was measured in the presence of a range of anlotinib concentrations. The protein expression level of ABCB1 was detected by Western blotting and immunofluorescence analysis. Our results showed that anlotinib significantly increased the sensitivity of KHOSR2 and U2OSR2 cells (which overexpress PGP1) to chemotherapeutic agents in vitro and in a KHOSR2 xenograft nude mouse model in vivo. Mechanistically, anlotinib increases the intracellular accumulation of PGP1 substrates by inhibiting the efflux function of PGP1 in multidrug-resistant cell lines. Furthermore, anlotinib stimulated the ATPase activity of PGP1 but affected neither the protein expression level nor the localization of PGP1. In animal studies, anlotinib in combination with doxorubicin (DOX) significantly decreased the tumor growth rate and the tumor size in the KHOSR2 xenograft nude mouse model. Overall, our findings suggest that anlotinib may be useful for circumventing MDR to other conventional antineoplastic drugs.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Huyan Meng ◽  
Guowei Wu ◽  
Xinsuo Zhao ◽  
Anhui Wang ◽  
Dekang Li ◽  
...  

AbstractRIPK1, a death domain-containing kinase, has been recognized as an important therapeutic target for inhibiting apoptosis, necroptosis, and inflammation under pathological conditions. RIPK1 kinase inhibitors have been advanced into clinical studies for the treatment of various human diseases. One of the current bottlenecks in developing RIPK1 inhibitors is to discover new approaches to inhibit this kinase as only limited chemotypes have been developed. Here we describe Necrostatin-34 (Nec-34), a small molecule that inhibits RIPK1 kinase with a mechanism distinct from known RIPK1 inhibitors such as Nec-1s. Mechanistic studies suggest that Nec-34 stabilizes RIPK1 kinase in an inactive conformation by occupying a distinct binding pocket in the kinase domain. Furthermore, we show that Nec-34 series of compounds can synergize with Nec-1s to inhibit RIPK1 in vitro and in vivo. Thus, Nec-34 defines a new strategy to target RIPK1 kinase and provides a potential option of combinatorial therapy for RIPK1-mediated diseases.


2015 ◽  
Vol 7 ◽  
pp. PMC.S13212 ◽  
Author(s):  
Sara Gordon ◽  
Johayra Simithy ◽  
Douglas C. Goodwin ◽  
Angela I. Calderón

Owing to the persistence of tuberculosis (TB) as well as the emergence of multidrug-resistant and extensively drug-resistant (XDR) forms of the disease, the development of new antitubercular drugs is crucial. Developing inhibitors of shikimate kinase (SK) in the shikimate pathway will provide a selective target for antitubercular agents. Many studies have used in silico technology to identify compounds that are anticipated to interact with and inhibit SK. To a much more limited extent, SK inhibition has been evaluated by in vitro methods with purified enzyme. Currently, there are no data on in vivo activity of Mycobacterium tuberculosis shikimate kinase ( MtSK) inhibitors available in the literature. In this review, we present a summary of the progress of SK inhibitor discovery and evaluation with particular attention toward development of new antitubercular agents.


2020 ◽  
Vol 26 (22) ◽  
pp. 2610-2619 ◽  
Author(s):  
Tarique Hussain ◽  
Ghulam Murtaza ◽  
Huansheng Yang ◽  
Muhammad S. Kalhoro ◽  
Dildar H. Kalhoro

Background: Inflammation is a complex response of the host defense system to different internal and external stimuli. It is believed that persistent inflammation may lead to chronic inflammatory diseases such as, inflammatory bowel disease, neurological and cardiovascular diseases. Oxidative stress is the main factor responsible for the augmentation of inflammation via various molecular pathways. Therefore, alleviating oxidative stress is effective a therapeutic option against chronic inflammatory diseases. Methods: This review article extends the knowledge of the regulatory mechanisms of flavonoids targeting inflammatory pathways in chronic diseases, which would be the best approach for the development of suitable therapeutic agents against chronic diseases. Results: Since the inflammatory response is initiated by numerous signaling molecules like NF-κB, MAPK, and Arachidonic acid pathways, their encountering function can be evaluated with the activation of Nrf2 pathway, a promising approach to inhibit/prevent chronic inflammatory diseases by flavonoids. Over the last few decades, flavonoids drew much attention as a potent alternative therapeutic agent. Recent clinical evidence has shown significant impacts of flavonoids on chronic diseases in different in-vivo and in-vitro models. Conclusion: Flavonoid compounds can interact with chronic inflammatory diseases at the cellular level and modulate the response of protein pathways. A promising approach is needed to overlook suitable alternative compounds providing more therapeutic efficacy and exerting fewer side effects than commercially available antiinflammatory drugs.


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