The epidermal growth factor receptor (EGFR) was found to be overexpressed in several cancers, especially in lung cancers. Finding new effective drug against EGFR is the key to cancer treatment. In this study, the GOLD docking algorithm was used to virtually screen for novel human EGFR inhibitors from the NCI database. Thirty‐four hit compounds were tested for EGFR‐tyrosine kinase (TK) inhibition. Two potent compounds, 1‐amino‐4‐(4‐[4‐amino‐2‐sulfophenyl]anilino)‐9,10‐dioxoanthracene‐2‐sulfonic acid (NSC125910), and nogalamycin N‐oxide (NSC116555) were identified with IC50 values against EGFR‐TK comparable to gefitinib; 16.14 and 37.71 nM, respectively. However, only NSC116555 demonstrated cytotoxic effects against non–small‐cell lung cancer, A549, shown in the cell cytotoxicity assay with an IC50 of 0.19 + 0.01 µM, which was more potent than gefitinib. Furthermore, NSC116555 showed cytotoxicity against A549 via apoptosis in a dose‐dependent manner.
Most patients suffering from non–small cell lung cancer (NSCLC) have epidermal growth factor receptor (EGFR) overexpression. Currently, EGFR tyrosine kinase inhibitors (TKIs) that act as the ATP‐analogs and monoclonal antibodies (MAbs) to EGFR‐ectodomain that block intracellular signaling are used for the treatment of advanced NSCLC. Unfortunately, adverse effects due to the TKI off‐target and drug resistance occur in a significant number of the treated patients while some NSCLC genotypes do not respond to the therapeutic MAbs. Thus, a more effective remedy for the treatment of EGFR‐overexpressed cancers is deemed necessary. In this study, VH/VHH displayed‐phage clones that are bound to recombinant EGFR‐TK were fished‐out from a humanized‐camel VH/VHH phage display library. VH/VHH of three phage‐infected Escherichia coli clones (VH18, VHH35, and VH36) were linked molecularly to nonaarginine (R9) for making them cell penetrable. R9‐VH18, R9‐VHH35, and R9‐VH36 were cytotoxic to human adenocarcinomic alveolar basal epithelial cells (A549) at the fifty percent inhibitory concentration (IC50) 0.181 ± 0.132, 0.00961 ± 0.00516, and 0.00996 ± 0.00752 μM, respectively, which were approximately 1000‐fold more effective than small molecular TKIs. R9‐VH18 and R9‐VH36 also delayed cancer cell migration in a scratch‐wound assay. Computerized homology modeling and intermolecular docking revealed that VH18 and VHH35 used CDR3 to interact with EGFR‐TK residues close to the catalytic site, which might sterically hinder the ATP‐binding of the TK; VH36 used CDR2 to bind at the asymmetric dimerization surface, which might disrupt EGFR dimerization leading to inhibition of intracellular signaling. The humanized‐cell penetrable nanobodies have a high potential for developing further towards a clinical application.
A series of 2,4 diamino-pyrimidines have been identified from an analysis of open access high throughput anti-malarial screening data reported by GlaxoSmithKline at the 3D7 and resistant Dd2 strains. SAR expansion has been performed using structural knowledge of the most plausible parasite target. Seventeen new analogs have been synthesized and tested against the resistant K1 strain of Plasmodium falciparum (Pf). The cytotoxicity of the compounds was assessed in Vero and A549 cells and their selectivity towards human kinases including JAK2 and EGFR were undertaken. We identified compound 5n and 5m as sub-micromolar inhibitors, with equivalent anti-malarial activity to Chloroquine (CQ). Compounds 5d and 5k, μM inhibitors of Pf, displayed improved cytotoxicity with weak inhibition of the human kinases.
A series of 2-amino-aryl-7-aryl-benzoxazole derivatives have been designed, synthesized, and evaluated as anticancer agents. Fourteen of the compounds exhibited cytotoxic effects toward human A549 lung cancer cells. We found 12l was the most potent with an EC of 0.4 μm, equivalent to the anticancer drug doxorubicin, but had low selectivity following cross screening in monkey kidney Vero cells. Eight of the most potent or most selective compounds were further profiled in additional cell lines (MCF7, NCI-H187, and KB) to better understand their cytotoxic activity. Only compound 12l had a measurable EC in a single cell line (3.3 μm in the KB cell line). Taken together, this data suggest the series as a whole display specific cytotoxicity toward A549 cells. Cheminformatics searches pointed to JAK2 as a possible target. A subset of compounds assayed at this target showed IC s ranging from 10 to 0.08 μm; however, no clear correlation between JAK2 potency and A549 cytotoxicity was observed.
Background:
Despite the development of extensive control strategies and treatment options,
approximately 200 million malaria cases, leading to approximately 450,000 deaths, were reported
in 2015. Due to issue of disease resistance, additional drug development efforts are needed
to produce new, more effective treatments. Quinazoline-2,4-diamines were identified as antiparasitic
compounds over three decades ago and have remained of interest to date in industry and
academia.
Objective:
An anti-malarial SAR evaluation of previously unreported N2
,N4
-disubstituted quinazoline-
2,4-diamines have been undertaken in this study. We have synthesized and evaluated new
derivatives against P. falciparum in our attempt to better characterize their biological activity and
overall physical properties.
Methods:
The synthesis of N2
,N4
-disubstituted quinazoline-2,4-diamines inhibitors is reported
along with activities in a radioactive labeled hypoxanthine incorporation assay against the f Plasmodium
falciparum (Pf.) K1 strain. In addition, cytotoxicity was determined in the A549 and Vero
cell lines using an MTT based. The aqueous solubility of key compounds was assessed at pH 7.4
using a shake flask-based approach.
Results:
We identified compounds 1 and 6p as sub µM inhibitors of P. falciparum, having equivalent
anti-malarial activity to Chloroquine. Compounds 1 and 6m are low µM inhibitors of P. falciparum
with improved cytotoxicity profiles. Compound 6m displayed the best balance between P.
falciparum Inhibitory activity (2 µM) and cytotoxicity, displaying >49 fold selectivity over A549
and Vero cell lines.
Conclusion:
Twenty one N2
,N4
-Disubstituted Quinazoline-2,4-diamines have been prepared in our
group and characterized in terms of their antimalarial activity, cytotoxicity and physical properties.
Compounds with good activity and reasonable selectivity over mammalian cell lines have been
identified. SAR analyses suggest further exploration is are necessary to improve the balance of P.
falciparum Inhibitory activity, cytotoxicity and solubility.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.