casein-kinase-ii and Carcinoma--Ehrlich-Tumor

Increased expression of the ubiquitous serine/threonine protein kinase CK2 has been associated with increased proliferative capacity and increased resistance towards apoptosis. Taurine is the primary organic osmolyte involved in cell volume control in mammalian cells, and shift in cell volume is a critical step in cell proliferation, differentiation and induction of apoptosis. In the present study, we use mouse NIH3T3 fibroblasts and Ehrlich Lettré ascites tumour cells with different CK2 expression levels. Taurine uptake via the Na(+) dependent transporter TauT and taurine release are increased and reduced, respectively, following pharmacological CK2 inhibition. The effect of CK2 inhibition on TauT involves modulation of transport kinetics, whereas the effect on the taurine release pathway involves reduction in the open-probability of the efflux pathway. Stimulation of PLA(2) activity, exposure to exogenous reactive oxygen species as well as inhibition of protein tyrosine phosphotases (PTP) potentiate the swelling-induced taurine loss. Inhibition of PI3K and PTEN reduces and potentiates swelling-induced taurine release, respectively. Inhibition of CK2 has no effect on PLA(2) activity and ROS production by NADPH oxidase, whereas it lifts the effect of PTEN and PTP inhibition. It is suggested that CK2 regulates the taurine release downstream to known swelling-induced signal transducers including PLA(2), NADPH oxidase and PI3K.

Topics: Animals; Apoptosis; Biological Transport; Carcinoma, Ehrlich Tumor; Casein Kinase II; Cell Size; Fibroblasts; Gene Expression; Homeostasis; Kinetics; Mice; NADPH Oxidases; NIH 3T3 Cells; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phospholipases A2; Protein Kinase Inhibitors; Protein Tyrosine Phosphatases; PTEN Phosphohydrolase; Reactive Oxygen Species; Signal Transduction; Taurine; Tumor Cells, Cultured; Water-Electrolyte Balance

The synthesis, in vivo and in vitro antitumor evaluation, and QSAR studies of some novel pyrazole analogs against Ehrlich Ascites Carcinoma (EAC) cells were described. In vitro results revealed that compounds 10, 6 and 4 were the most potent analogs against EAC, respectively. Moreover, in vivo evaluation of compounds 6 and 10 proved their capability to normalize the blood picture in comparison to 5-FU, a well known anticancer drug. These novel pyrazole analogs were molecularly designed with the goal of having significant potent cytotoxic effect against EAC cells. To develop a QSAR model capable of identifying the key molecular descriptors associated with the biological activity of the novel pyrazole analogs and predicting the cytotoxic effect for other novel pyrazole analogs against EAC cells, different QSAR models, using different physicochemical and topological molecular descriptors, were developed. Different molecular descriptors were predicted solely from the chemical structures of 16 pyrazolo-diazine and triazine analogs following the prediction of the equilibrium molecular geometry of each analog at the DFT level using B88-LYP functional energy and double zeta valence polarized (DZVP) basis set. It was found that dipole moment, excitation energy, the energy value of LUMO, solvent accessible surface area, and heat of formation were the key molecular descriptors in descriping the cytotoxic effect of those compounds against EAC.

Topics: Animals; Antineoplastic Agents; Azo Compounds; Carcinoma, Ehrlich Tumor; Casein Kinase II; Catalytic Domain; Cell Line, Tumor; Cell Survival; Male; Mice; Models, Molecular; Molecular Structure; Protein Binding; Pyrazoles; Quantitative Structure-Activity Relationship; Survival; Triazines

By means of successive GL-affinity and Mono S column chromatographies (HPLC), a 100 kDa GL-binding protein (gp100) was purified from the partially purified CK-II fraction of EAT cells as an effective phosphate acceptor for CK-II. It was found that (i) gp100 (pI 9.0) is copurified with CK-II, Hsp-90 and p34 or p70; (ii) gp100 cross-reacts with anti-human GR; (iii) phosphorylation of gp100 by CK-II is significantly stimulated by 1 microM GL or 0.3 microM oGA; and (iv) GL as well as DEX inhibit it at doses above 3 microM. Data are provided to suggest that the GL-induced selective inhibition of the CK-II catalyzed phosphorylation of gp100 may be involved in the anti-inflammatory effects of GL.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Carcinoma, Ehrlich Tumor; Carrier Proteins; Casein Kinase II; Chickens; Chromatography, Affinity; Chromatography, High Pressure Liquid; Chromatography, Ion Exchange; Dexamethasone; Electrophoresis, Polyacrylamide Gel; Glycyrrhetinic Acid; Glycyrrhizic Acid; Heat-Shock Proteins; HSP90 Heat-Shock Proteins; Humans; Kinetics; Mice; Molecular Sequence Data; Molecular Weight; Phosphorylation; Protein Serine-Threonine Kinases; Sequence Homology, Amino Acid