Docking and three-dimensional quantitative structure-activity relationship analyses of imidazole and thiazolidine derivatives as Aurora A kinase inhibitors.

Aurora A kinase is involved in the inactivation of apoptosis leading to ovarian, breast, colon, and pancreatic cancers. Inhibitors of Aurora A kinase promote aberrant mitosis resulting in arrest at a pseudo G1 state to induce mitotic catastrophe, ultimately leading to apoptosis. In this study, ligand-based and docking-based three-dimensional quantitative structure-activity relationship (3D-QSAR) analyses of imidazole and thiazolidine derivatives as potential Aurora A kinase inhibitors were performed.

Cytotoxicity and Structure-activity Relationships of Naphthyridine Derivatives in Human Cervical Cancer, Leukemia, and Prostate Cancer.

Naphthyridine compounds are important, because they exhibit various biological activities including anticancer, antimicrobial, and anti-inflammatory activity. Some naphthyridines have antimitotic effects or demonstrate anticancer activity by inhibiting topoisomerase II. These compounds have been investigated as potential anticancer agents, and several compounds are now part of clinical trials.

Cytotoxic activity and quantitative structure activity relationships of arylpropyl sulfonamides.

B13 is a ceramide analogue and apoptosis inducer with potent cytotoxic activity. A series of arylpropyl sulfonamide analogues of B13 were evaluated for their cytotoxicity using MTT assays in prostate cancer PC-3 and leukemia HL-60 cell lines. Some compounds (4, 9, 13, 14, 15, and 20) showed stronger activities than B13 in both tumor cell lines, and compound (15) gave the most potent activity with IC50 values of 29.

Cytotoxicities and Quantitative Structure Activity Relationships of B13 Sulfonamides in HT-29 and A549 Cells.

B13 analogues are being considered as therapeutic agents for cancer cells, since B13 is a ceramide analogue and inhibits ceramidase to promote apoptosis in cancer cells. B13 sulfonamides are assumed to have biological activity similar to B13, since they are made by bioisosterically substituting the carboxyl moiety of B13 with sulfone group. Twenty B13 sulfonamides were evaluated for their in vitro cytotoxicities against human colon cancer HT-29 and lung cancer A549 cell lines using MTT assays.

The effect of quercetin-3-O-β-D-glucuronopyranoside on indomethacin-induced gastric damage in rats via induction of mucus secretion and down-regulation of ICAM-1 expression.

The mechanism of the protective effect of quercetin-3-O-β-D-glucuronopyranoside (QGC) from the leaves of Rumex aqauticus on indomethacin (IND, a representative NSAID)-induced gastric damage in rats was investigated. Pre-treatment with QGC significantly attenuated IND-induced gastric mucosal injury. An increase in myeloperoxidase (MPO) activity and expression of intercellular adhesion molecule (ICAM)-1 protein and mRNA expression of the pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β, as well as a decrease in gastric mucus secretion were detected in the gastric mucosa of IND-treated rats.

Cytotoxic Activity and Structure Activity Relationship of Ceramide Analogues in Caki-2 and HL-60 Cells.

B13, a ceramide analogue, is a ceramidase inhibitor and induces apoptosis to give potent anticancer activity. A series of thiourea B13 analogues was evaluated for their in vitro cytotoxic activities against human renal cancer Caki-2 and leukemic cancer HL-60 in the MTT assay. Some compounds (12, 15, and 16) showed stronger cytotoxicity than B13 and C6-ceramide against both tumor cell lines, and compound (12) gave the most potent activity with IC(50) values of 36 and 9 µM, respectively.

MLCK and PKC Involvements via Gi and Rho A Protein in Contraction by the Electrical Field Stimulation in Feline Esophageal Smooth Muscle.

We have shown that myosin light chain kinase (MLCK) was required for the off-contraction in response to the electrical field stimulation (EFS) of feline esophageal smooth muscle. In this study, we investigated whether protein kinase C (PKC) may require the on-contraction in response to EFS using feline esophageal smooth muscle. The contractions were recorded using an isometric force transducer.

Cytotoxic Activity and Three-Dimensional Quantitative Structure Activity Relationship of 2-Aryl-1,8-naphthyridin-4-ones.

A series of substituted 2-arylnaphthyridin-4-one analogues, which were previously synthesized in our laboratory, were evaluated for their in vitro cytotoxic activity against human lung cancer A549 and human renal cancer Caki-2 cells using MTT assay. Some compounds (11, 12, and 13) showed stronger cytotoxicity than colchicine against both tumor cell lines, and compound 13 exhibited the most potent activity with IC(50) values of 2.3 and 13.

The influences of g proteins, ca, and k channels on electrical field stimulation in cat esophageal smooth muscle.

NO released by myenteric neurons controls the off contraction induced by electrical field stimulation (EFS) in distal esophageal smooth muscle, but in the presence of nitric oxide synthase (NOS) inhibitor, L-NAME, contraction by EFS occurs at the same time. The authors investigated the intracellular signaling pathways related with G protein and ionic channel EFS-induced contraction using cat esophageal muscles. EFS-induced contractions were significantly suppressed by tetrodotoxin (1 microM) and atropine (1 microM).

Quantitative Structure Activity Relationship between Diazabicyclo[4.2.0]octanes Derivatives and Nicotinic Acetylcholine Receptor Agonists.

Three dimensional quantitative structure activity relationship between diazabicyclo[4.2.0]octanes and nicotinic acetylcholine receptor (halpha4beta2 and halpha3beta4) agonists was studied using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA).

Synthesis and cytotoxicity of new aromatic ceramide analogs with alkylsulfonamido chains.

A series of D-erythro ceramide analogues, N-(2S, 3R, 4E)-1, 3-dihydroxy-5-phenyl pent-4-en-2-yl alkyl sulfonamides, were synthesized and evaluated for their in vitro cytotoxic activities against five human tumor cell lines. The aromatic sulfon amido ceramide analogue (10f) showed more potent cytotoxic activity than that of the B13, indicating that a sulfonamide group appears to serve as a bioisostere of an amide in drug design. Variations in the alkyl sulfonyl chain length significantly influenced the cytotoxic activity of the sulfonamido ceramide analogues, but the introduction of a para halogen on the phenyl ring of aromatic ceramide analogues had no affect on the activity.

Synthesis and cytotoxicity of new 3-alkyl-1-(1-methyl-2-phenylethyl)ureas related to ceramide.

A series of new 3-alkyl-1-(1-methyl-2-phenylethyl)ureas related to ceramide was synthesized and evaluated for their in vitro cytotoxic activity against five human tumor cell lines. The urea analogue (2b) of B13 showed comparable or slightly more potent cytotoxic activity as compared to B13, indicating that urea does appear to serve as a bioisostere of amide.