Discovery of an anticancer medicine using a single target protein has often been unsuccessful due to the complexity of pathogenic mechanisms as well as the presence of redundant signaling pathways. In this work, we attempted to find promising anticancer drug candidates by simultaneously targeting casein kinase 1 delta (CK1δ) and muscarinic acetylcholine receptor M3 (M3R). Through the structure-based virtual screening and de novo design with the modified potential function for protein-ligand binding, a series of benzo[4,5]imidazo[1,2-a][1,3,5]triazine-2-amine (BITA) derivatives were identified as CK1δ inhibitors and also as M3R antagonists.
View Article and Find Full Text PDFThe phosphoinositide 3‑kinase (PI3K) signaling pathway plays an important role in human cancer as it regulates critical cellular functions, such as survival, proliferation and metabolism. In the present study, a novel PI3Kα inhibitor (HS‑146) was synthesized and its anticancer effects on MCF‑7, MDA‑MB‑231, SKBR3 and BT‑474 human breast cancer cell lines were confirmed. HS‑146 was found to be most effective in inhibiting the proliferation of MCF‑7 cells and in inducing cell cycle arrest in the G0/G1 phase by downregulating cyclin D1, cyclin E, cyclin‑dependent kinase (Cdk)2 and Cdk4, and upregulating p21Waf1/Cip1 protein levels in this cell line.
View Article and Find Full Text PDFNecroptosis is a form of regulated necrotic cell death mediated by receptor-interacting kinase 3 (RIP3). Recently, necroptosis has gained attention as a novel alternative therapy to target cancer cells. In this study, we screened several chemotherapeutics used in preclinical and clinical studies, and identified a drug HS-173 that induces RIP3-mediated necroptosis.
View Article and Find Full Text PDFAltered expression or hyperactivation of anaplastic lymphoma kinase (ALK), as a consequence of translocations or point mutations, is one of the main oncogenic drivers in non-small cell lung cancer. Using structure-based design and in vitro enzyme assays, we identified 3-heteroarylcoumarin as a new template for the development of novel fluorescent ALK inhibitors. Molecular simulation provided structural insights for the design of 3-heteroarylcoumarin derivatives, which were easily prepared through efficient synthetic approaches including direct C-H cross coupling.
View Article and Find Full Text PDFNecroptosis is a type of programmed cell death that usually occurs under apoptosis-deficient conditions. Receptor-interacting protein kinase-3 (RIP3, or RIPK3) is a central player in necroptosis, and its kinase activity is essential for downstream necroptotic signaling events. Since RIP3 kinase activity has been associated with various diseases, the development of specific RIP3 inhibitors is an attractive strategy for therapeutic application.
View Article and Find Full Text PDFDysregulation of anaplastic lymphoma kinase (ALK) has been detected in nonsmall cell lung cancer (NSCLC) in the form of EML4-ALK fusion. Secondary mutations opposing activity of the first-generation ALK inhibitor crizotinib came into existence, requiring mutation-targeting drug discovery for the powerful second-line treatment. In this study, we report 4-phenoxyquinoline-based inhibitors that overcome crizotinib resistance to ALK L1196M, discovered by the fragment-growing strategy.
View Article and Find Full Text PDFFascaplysin has been reported to exert anti-cancer effects by inhibiting cyclin-dependent kinase 4 (CDK4); however, the precise mode of action by which fascaplysin suppresses tumor growth is not clear. Here, we found that fascaplysin has stronger anti-cancer effects than other CDK4 inhibitors, including PD0332991 and LY2835219, on lung cancer cells that are wild-type or null for retinoblastoma (RB), indicating that unknown target molecules might be involved in the inhibition of tumor growth by fascaplysin. Fascaplysin treatment significantly decreased tumor angiogenesis and increased cleaved-caspase-3 in xenografted tumor tissues.
View Article and Find Full Text PDFNext-generation epidermal growth factor receptor (EGFR) inhibitors against the d746-750/T790M/C797S mutation were discovered through two-track virtual screening and de novo design. A number of nanomolar inhibitors were identified using 2-aryl-4-aminoquinazoline as the molecular core and the modified binding energy function involving a proper dehydration term, which provides important structural insight into the key principles for high inhibitory activities against the d746-750/T790M/C797S mutant. Furthermore, some of these EGFR inhibitors showed a greater than 1000-fold selectivity for the d746-750/T790M/C797S mutant over the wild type, as well as nanomolar activity against the mutant.
View Article and Find Full Text PDFAlthough anaplastic lymphoma kinase (ALK) is involved in a variety of malignant human cancers, the emergence of constitutively active mutants with drug resistance has rendered it difficult to identify the new medicines for ALK-dependent cancers. To find the common inhibitors of the wild type ALK and the most abundant drug-resistant mutant (L1196M), we performed molecular docking-based virtual screening of a large chemical library in parallel for the two target proteins. As a consequence of augmenting the accuracy of the docking simulation by implementing a sophisticated hydration free energy term in the scoring function, 12 common inhibitors are discovered with the inhibitory activities ranging from submicromolar to low micromolar levels.
View Article and Find Full Text PDFThe catalyst-controlled C4/C8 site-selective C-H arylation of isoquinolones using aryliodonium salts as the coupling partners was developed. The C4-selective arylation was successfully achieved via an electrophilic palladation pathway. A completely different selectivity pattern was observed using an Ir(III) catalytic system, which resulted in C-C bond formation exclusively at the C8 position.
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