Alzheimer's disease is an irreversible neurodegenerative disorder that is characterized by the abnormal aggregation of amyloid-β into neurotoxic oligomers and plaques. Although many disease-modifying molecules are currently in Alzheimer clinical trials, a small molecule that inhibits amyloid-β aggregation and ameliorates the disorder has not been approved to date. Herein, we report the effects of a potent small molecule, 6-methoxy-2-(4-dimethylaminostyryl) benzofuran (KMS88009), that directly disrupts amyloid-β oligomerization, preserving cognitive behavior when used prophylactically and reversing declines in cognitive behavior when used therapeutically.
View Article and Find Full Text PDFAlzheimer's disease drug discovery regarding exploration into the molecules and processes has focused on the intrinsic causes of the brain disorder correlated with the accumulation of amyloid-β. An anti-amyloidogenic bis-styrylbenzene derivative, KMS80013, showed excellent oral bioavailability (F=46.2%), facilitated brain penetration (26%, iv) in mouse and target specific in vivo efficacy in acute AD mouse model attenuating the cognitive deficiency in Y-maze test.
View Article and Find Full Text PDFHM781-36B is an orally administered pan-human epidermal growth factor receptor (HER) inhibitor. To explore the role of pan-HER inhibitor in breast cancer, we investigated the antitumor effect and mechanisms of HM781-36B in breast cancer cell lines. Six breast cancer cell lines (BT474, MDA-MB-453, SK-BR-3, T47D, MCF-7, and MDA-MB-231) were tested.
View Article and Find Full Text PDFA novel series of N(4)-(3-chlorophenyl)-5-(oxazol-2-yl)pyrimidine-4,6-diamines were synthesized and evaluated as dual inhibitors of HER-1/HER-2 tyrosine kinases. In contrast to the currently approved HER-2-targeted agent (lapatinib, 1), our irreversible HER-1/HER-2 inhibitors have the potential to overcome the clinically relevant and mutation-induced drug resistance. The selected compound (19a) showed excellent inhibitory activity toward HER-1/HER-2 tyrosine kinases with selectivity over 20 other kinases and inhibited the proliferation of both cancer cell types: lapatinib-sensitive cell lines (SK-Br3, MDA-MB-175, and N87) and lapatinib-resistant cell lines (MDA-MB-453, H1781, and H1975).
View Article and Find Full Text PDFThe epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases has been implicated in a variety of cancers. In particular, activating mutations such as the L858R point mutation in exon 21 and the small in-frame deletions in exon 19 of the EGFR tyrosine kinase domain are correlated with sensitivity to EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC) patients. Clinical treatment of patients is limited by the development of drug resistance resulting mainly from a gatekeeper mutation (T790M).
View Article and Find Full Text PDFTrastuzumab, a HER2 directed treatment has shown clinical benefit in HER2 amplified gastric cancer. This study demonstrated the potent antitumor activity of HM781-36B, a quinazoline-based irreversible pan-HER inhibitor, in HER2 amplified gastric cancer cells (SNU216 and N87) in vitro and in vivo. HM781-36B inhibited phosphorylation of HER family and downstream signaling molecules, and induced apoptosis and G1 arrest.
View Article and Find Full Text PDFVirtual screening was performed to determine potent vascular endothelial growth factor receptor (VEGFR)-2 kinase inhibitors. A database of approximately 820,000 commercial compounds was used for screening, and 100 compounds were chosen as candidate VEGFR-2 inhibitors through pharmacophore modeling and docking studies. These 100 compounds were purchased to test their biological activities: 10 compounds were found to inhibit the enzyme, with IC(50) values ranging from 10 to 1 μM.
View Article and Find Full Text PDFMulti-drug resistance 1 (MDR1, ABCB1), also known as P-glycoprotein (P-gp), restricts intestinal uptake of many drugs, and contributes to cellular resistance to cancer chemotherapy. In this study, we examined the pharmacologic characteristics of HM30181, a newly developed MDR1 inhibitor, and tested its capacity to increase the oral bioavailability and efficacy of paclitaxel, an anti-cancer drug usually given by intravenous injection. In the ATPase assay using MDR1-enriched vesicles, HM30181 showed the highest potency (IC(50)=0.
View Article and Find Full Text PDFA novel series of (S)-1-acryloyl-N-[4-(arylamino)-7-(alkoxy)quinazolin-6-yl]pyrrolidine-2-carboxamides were synthesized and evaluated as Her-1/Her-2 dual inhibitors. In contrast to the Her-1 selective inhibitors, our novel compounds are irreversible inhibitors of Her-1 and Her-2 tyrosine kinases with the potential to overcome clinically relevant, mutation-induced drug resistance. The selected compounds (19c, 19d) showed excellent EGFR inhibition activity even toward the T790M mutation of Her-1 tyrosine kinase with excellent selectivity.
View Article and Find Full Text PDFSrc is an important target in multiple processes associated with tumor growth and development, including proliferation, neovascularization, and metastasis. In this study, hit identification was performed by virtual screening of commercial and in-house compound libraries. Docking studies for the hits were performed, and scoring functions were used to evaluate the docking results and to rank ligand-binding affinities.
View Article and Find Full Text PDFP-glycoprotein (P-gp), a factor responsible for the multidrug resistance of tumors, is specifically expressed in brain microenvironment. To test its roles in brain metastatic tumor chemoresistance, we implanted the paclitaxel-sensitive melanoma cell line, K1735, into the skin or brain of mice and examined its paclitaxel resistances. When implanted into the skin, paclitaxel inhibited tumor growth, however, it had no inhibitory effect on cells implanted into the brain.
View Article and Find Full Text PDFThe objective of this study was to examine the antitumor effect of ZD6474, an orally available inhibitor of the vascular endothelial growth factor receptor-2 (VEGFR-2) and the epidermal growth factor receptor (EGFR), on tumor growth in an orthotopic metastatic brain tumor model. In order to determine the antitumor mechanism of ZD6474 treatment, in vitro and in vivo studies were performed. Human breast carcinoma cells (MDA-MB-435) were injected using direct intracranial (IC) inoculation (5x105 cells/100 µl) and internal carotid artery (ICA) injection (5x104 cells/100 µl) in Balb/c-nu female mice.
View Article and Find Full Text PDFHM-30181, 4-oxo-4H-chromene-2-carboxylic acid [2-(2-{4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl}-2H-tetrazol-5-yl)-4,5-dimethoxy-phenyl]-amide, is a new P-glycoprotein inhibitor with the potential to increase the cytotoxic activity of orally coadministered paclitaxel. This study was performed to characterize human cytochrome P-450 (CYP) enzymes involved in the metabolism of HM-30181 to 4- or 5-O-desmethyl-HM-30181 (M2) and 6- or 7-O-desmethyl-HM-30181 (M3) and to investigate the inhibitory potential of HM-30181 on CYP enzymes in human liver microsomes. CYP3A4 was identified as the major isozyme responsible for the O-demethylation of HM-30181 to M2 and M3 based on the correlation analysis, chemical inhibition and immuno-inhibition study and metabolism in cDNA-expressed human CYP isozymes.
View Article and Find Full Text PDFHM-30181, 4-oxo-4H-chromene-2-carboxylic acid, [2-(2-{4-[2-(6,7-dimethoxy-3,4-dihydro-1H-isoquinolin-2-yl)-ethyl]-phenyl}-2H-tetrazol-5-yl)-4,5-dimethoxyphenyl]amide, is a new P-glycoprotein inhibitor. This study was performed to identify the in vitro and in vivo metabolic pathway of HM-30181 in rats. Rat liver microsomal incubation of HM-30181 in the presence of NADPH resulted in the formation of four metabolites, M1-M4.
View Article and Find Full Text PDFToxicogenomics, the subdiscipline that merges genomics with toxicology, hold the promise to contributing toward the goal of elucidating mechanism by studying genomic profiling related with various drugs. The application of gene expression profiling technology to examine multiple genes and signaling pathways promises a significant advance in understanding the toxic mechanisms of various drugs and prediction of new drug candidate. Toxicogenomics is emerging field combining genomics and bioinformatics to identify and characterize mechanisms of toxicity of drug and various compounds.
View Article and Find Full Text PDFBackground: Paclitaxel has been shown to inhibit vascular smooth muscle cell migration and proliferation contributing to neointimal formation. This study tested whether novel oral formulations of paclitaxel can prevent neointimal formation in a rat carotid artery injury model.
Methods And Results: Oral formulations of paclitaxel (0, 5, 7.