BACKGROUND: Non-small cell lung cancer (NSCLC) patients often benefit from EGFR inhibitors like gefitinib. However, drug resistance remains a significant challenge in treatment. The unique properties of 1,2,3-triazole, a nitrogen-based compound, hold promise as potential solutions due to its versatile structural attributes and diverse biological effects, including anticancer properties.
METHODS: Our synthesis process involved the huisgen cycloaddition chemical method, which generated diverse icotinib derivatives. We evaluated the anticancer capabilities of these derivatives against various cancer cell lines, with a specific focus on NSCLC cells that exhibit drug resistance. Additionally, we investigated the binding affinity of selected compounds, including 3l, towards wild-type EGFR using surface plasmon resonance (SPR) experiments.
RESULTS: Notably, icotinib derivatives such as derivative 3l demonstrated significant efficacy against different cancer cell lines, including those resistant to conventional therapies. Compound 3l exhibited potent activity with IC50 values below 10 μM against drug-resistant cells. SPR experiments revealed that 3l exhibited enhanced affinity towards wild-type EGFR compared to icotinib. Our research findings suggest that 3l acts as a compelling antagonist for the protein tyrosine kinase of EGFR (EGFR-PTK).
CONCLUSIONS: Icotinib derivative 3l, featuring a 1,2,3-triazole ring, demonstrates potent anticancer effects against drug-resistant NSCLC cells. Its enhanced binding affinity to EGFR and modulation of the EGFR-RAS-RAF-MAPK pathway position 3l as a promising candidate for the future development of anticancer drugs.

BACKGROUND: Overactivation of receptors that respond to excitatory neurotransmitters can result in various harmful outcomes, such as the inability to properly modulate calcium levels, generation of free radicals, initiation of the mitochondrial permeability transition, and subsequent secondary damage caused by excitotoxicity. A non-proteinogenic amino acid of tea, L-theanine, is structurally related to glutamate, the major stimulatory neurotransmitter in the brain. Previous reports have emphasised its ability to bind with glutamate receptors.
OBJECTIVE: An in-depth understanding of the binding compatibility between ionotropic glutamate receptors and L-theanine is a compelling necessity.
METHODS: In this molecular docking study, the antagonistic effect of L-theanine and its possible therapeutic benefit in GluR5 kainate receptor inhibition has been evaluated and compared to the familiar AMPA and kainite receptor antagonists, cyanoquinoxaline (CNQX) and dinitroquinoxaline (DNQX), using Molegro Virtual Docker 7.0.0.
RESULTS: The capacity of L-theanine to cohere with the GluR5 receptor was revealed to be higher than that of glutamate, although it could not surpass the high binding tendency of competitive antagonists CNQX and DNQX. Nonetheless, the drug-likeness score and the blood-brain barrier traversing potential of L-theanine were higher than CNQX and DNQX.
CONCLUSIONS: The study provides an inference to the advantage of L-theanine, which can be a safe and effective alternative natural therapy for rescuing neuronal death due to excitotoxicity.

BACKGROUND: Nicotinamide N-methyltransferase (NNMT) catalyzes the N-methylation of nicotinamide with S-adenosine-L-methionine (SAM) as the methyl donor. Abnormal expression of NNMT is associated with many diseases (such as multiple cancers and metabolic and liver diseases), making NNMT a potential therapeutic target. Limited studies concerning the enzymesubstrate/ inhibitor interactions could be found to fully understand the detailed reaction mechanism.
METHODS: The binding affinity and ligand binding epitopes of nicotinamide or SAH for binding NNMT and its mutants were determined using saturated transfer difference (STD) nuclear magnetic resonance (NMR) techniques combined with site-directed mutagenesis.
RESULTS: The average dissociation constant of WT NNMT with nicotinamide and S-adenosine homocysteine (SAH) was 5.5 ± 0.9 mM and 1.2 ± 0.3 mM, respectively, while the mutants Y20F and Y20G with nicotinamide were up to nearly 4 times and 20 times that of WT and with SAH nearly 2 times and 5 times that of WT. The data suggested that WT had the highest binding affinity for nicotinamide or SAH, followed by Y20F and Y20G, which was consistent with its catalytic activity.
CONCLUSIONS: The binding affinity of nicotinamide and SAH to NNMT and its mutants were obtained by STD NMR in this study. It was found that nicotinamide and SAH bind to WT in a particular orientation, and Y20 is critical for their binding orientation and affinity to NNMT.

Development of alternative linear peptides for targeting αvβ3 integrin has attracted much attention, as the traditional peptide ligand, cyclic RGD, is limited by inferior water-solubility and complex synthesis. Using pharmacophore-based virtual screening and high-throughput molecular docking, we identified two novel linear small peptides RWr and RWrNM with high affinity and specificity to αvβ3 integrin. The competitive binding with cyclic RGD (c(RGDyK)) and cellular uptake related to the integrin expression levels verified their affinity to αvβ3 integrin. The intermolecular interaction measurement and dynamics simulation demonstrated the high binding affinity and stability, especially for RWrNM. In vivo peptide-guided tumor imaging and targeted therapy further confirmed their specificity. Results indicated that the newly identified small linear peptide RWrNM, with high affinity and specificity to αvβ3 integrin, better water-solubility, and simplified synthetic process, could overcome limitations of the current cyclic RGD peptides, paving the way for diverse use in diagnosis and therapy.