Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.10.2 (focal adhesion kinase)
 44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The search for effective chemopreventive compounds is a major challenge facing research into preventing the progression of cancer cells. The naturally occurring polyphenol antioxidants look very promising, but their mechanism of action still remains poorly understood. Here, we show that 2-(3,4-dihydroxyphenyl)ethanol (DPE), a phenol antioxidant derived from olive oil, induces growth arrest and apoptosis in human colon carcinoma HT-29 cells. The mechanisms involve prolonged stress of the endoplasmic reticulum (ER) leading to the activation of the two main branches of the unfolded protein response (UPR), including the Ire1/XBP-1/GRP78/Bip and PERK/eIF2alpha arms. DPE treatment led to overexpression of the pro-apoptotic factor CHOP/GADD153 and persistent activation of the Jun-NH2-terminal kinase/activator protein-1 signaling pathway. DPE concomitantly modulated the extracellular signal-regulated kinase 1/2 and Akt/PKB pro-survival factors by altering their phosphorylation status as well as inhibiting tumor necrosis factor-alpha-induced nuclear factor-kappaB activation by inactivating the phosphorylation of nuclear factor inhibitor-kappaB kinase. These findings prompted us to investigate the possible involvement of phosphatases in DPE-mediated action. Using phosphatase inhibitors and RNA interference to silence the Ser/Thr phosphatase 2A (PP2A) prevented DPE-induced cell death. These findings demonstrate that DPE specifically activates PP2A, which plays a key initiating role in various pathways that lead to apoptosis in colon cancer cells.
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PMID:Dihydroxyphenylethanol induces apoptosis by activating serine/threonine protein phosphatase PP2A and promotes the endoplasmic reticulum stress response in human colon carcinoma cells. 1652 88

Arthrobacter sp. lipase (ABL, MTCC no. 5125) is being recognized as an efficient enzyme for the resolution of drugs and their intermediates. The immobilization of ABL on various matrices for its enantioselectivity, stability, and reusability has been studied. Immobilization by covalent bonding on sepharose and silica afforded a maximum of 380 and 40 IU/g activity, respectively, whereas sol-gel entrapment provided a maximum of 150 IU/g activity in dry powder. The immobilized enzyme displayed excellent stability in the pH range of 4-10 and even at higher temperature, i.e., 50-60 degrees C, compared to free enzyme, which is unstable under extreme conditions. The resolution of racemic auxiliaries like 1-phenyl ethanol and an intermediate of antidepressant drug fluoxetine, i.e., ethyl 3-hydroxy-3-phenylpropanoate alkyl acylates, provided exclusively R-(+) products ( approximately 99% ee, E=646 and 473), compared to cell free extract/whole cells which gave a product with approximately 96% ee (E=106 and 150). The repeated use (ten times) of covalently immobilized and entrapped ABL resulted in no loss in activity, thus demonstrating its prospects for commercial applications.
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PMID:Arthrobacter sp. lipase immobilization for improvement in stability and enantioselectivity. 1689 4

Acetaldehyde is one of the most prevalent carcinogens in cigarette smoke. It is also a major metabolite of ethanol and is found widely in the human diet and environment. Acetaldehyde DNA adducts are critical for its carcinogenic properties. The role of acetaldehyde DNA adducts in human cancer related to tobacco and alcohol exposure could be investigated with a suitable biomarker. Therefore, in this study, we have developed a method for analysis of the major DNA adduct of acetaldehyde, N2-ethylidene-dGuo (1), in human leukocyte DNA. Leukocyte DNA was subjected to enzyme hydrolysis in the presence of NaBH3CN, which converts adduct 1 to N2-ethyl-dGuo (2). [15N5]N2-ethyl-dGuo was used as the internal standard. After solid-phase extraction, N2-ethyl-dGuo was quantified by LC-ESI-MS/MS-SRM. The method was sensitive, accurate, and precise, and applicable to low microgram amounts of DNA. It was applied to investigate the effect of smoking cessation on levels of adduct 1, measured as adduct 2. Twenty-five smokers who were only light drinkers were eligible for the study. Levels of adduct 2 were quantified at two baseline time points separated by one week and again after four weeks of abstinence from smoking and alcohol consumption. The mean (+/-S.D.) levels of adduct 2 measured in the leukocytes of the smokers were 1310 +/- 1720 (range 124-7700) and 1120 +/- 1140 (range 138-5760) fmol/micromol dGuo at the two baseline points and 705 +/- 438 (range 111-1530) fmol/micromol dGuo after 4 weeks of cessation. The median level of adduct 2 decreased significantly by 28% upon quitting smoking (P = 0.02). These results demonstrate that the major acetaldehyde DNA adduct can be reliably quantified by MS/MS methods in human leukocyte DNA and that cigarette smoking has a modest but significant effect on its levels.
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PMID:Quantitation of an acetaldehyde adduct in human leukocyte DNA and the effect of smoking cessation. 1722 33

The purpose of this study was to assess associations between substance use (alcohol to intoxication, heroin, and cocaine) and sexual activity, high risk sexual behaviors, and STD among detoxification inpatients (n = 470). Participants were surveyed on past 30 day substance use, past 6 month sexual behaviors, and STD in the past 6 months and/or over 24 months of follow-up. Logistic regression models adjusted for demographics found that cocaine use was significantly associated with being sexually active (OR(adj) = 2.3, 95% CI = 1.1-4.8) and selling sex (OR(adj) = 2.6, 95% CI = 1.3-5.3). Alcohol and heroin were not significantly associated with sexual activity, high risk sexual behaviors or STD in this sample.
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PMID:Associations between alcohol, heroin, and cocaine use and high risk sexual behaviors among detoxification patients. 1736 58

Addition of both a 4-fluoro and 11beta-methoxy group onto 16alpha-[(18)F]fluoroestradiol ([(18)F]FES) yields 11beta-methoxy-4,16alpha-[16alpha-(18)F]difluoroestradiol (4F-M[(18)F]FES) with potential improved properties for positron emission tomography (PET) imaging of estrogen receptor densities in breast cancer patients. In order to provide 4F-M[(18)F]FES as a radiopharmaceutical for clinical trials, we developed an automated synthesis procedure using 3-O-methoxymethyl-11beta-methoxy-4-fluoro-16,17-O-sulfuryl-16-epiestriol as precursor. The radio synthesis involves stereoselective opening of the protected cyclic sulfone precursor via nucleophilic fluorination with [(18)F]fluoride in acetonitrile. After removal of the protecting ether and 17beta-sulphate groups by rapid hydrolysis in acidic ethanol and subsequent reversed-phase HPLC purification, the pure 4F-M[(18)F]FES was obtained as a sterile physiological saline solution in 45-50% radiochemical yield (decay corrected). The radiochemical purity of the final product was >98% and the effective specific activity (ESA) of 4F-M[(18)F]FES prepared under optimized conditions was >15,000 Ci/mmol. The total preparation time was 110+/-5 min and the product was shown to be stable for at least 6 h.
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PMID:Automated synthesis of 11beta-methoxy-4,16alpha-[16alpha-(18)F]difluoroestradiol (4F-M[(18)F]FES) for estrogen receptor imaging by positron emission tomography. 1749 36

Arsenic in the drinking water may promote vascular diseases in millions of people worldwide through unresolved mechanisms. In addition, little is known of the effects of coexposures to arsenic and other common vasculature toxicants, such as alcohol. To investigate signaling interactions between arsenic and alcohols, primary human microvascular endothelial (HMVEC) cells were exposed to noncytotoxic concentrations of arsenite (1-5 microM) in the presence or absence of 0.1% ethanol (EtOH). Coexposure, but not exposure to either agent alone, rapidly increased active Fyn tyrosine kinase, tyrosine phosphorylation of a 109-kDa protein and serine phosphorylation of protein kinase C (PKC)delta. The 109-kDa protein was identified as PYK2, a regulator of vascular integrin signaling and an upstream activator of PKCdelta. Membrane localization of phospholipase Cgamma1 was increased by coexposure within 15 min, but not by either agent alone. In contrast, both agents equally increased membrane localization of Rac1-GTPase. Coexposure, but not exposure to either agent alone, induced transcript levels for the angiogenic genes, vascular endothelial cell growth factor (Vegfa) and insulin-like growth factor-1 (Igf1). However, EtOH inhibited arsenic-induced, nuclear factor-kappaB-driven interleukin-8 and collagen-1 expression. Differential effects of selective PKC inhibitors on induced gene expression combined with a lack of interaction for induction of hemeoxygenase-1 further demonstrated that arsenic-responsive signaling pathways differ in sensitivity to EtOH interactions. Finally, coexposure enhanced endothelial tube formation in in vitro angiogenesis assays. These data indicate that complex interactions occur between arsenic and EtOH exposures that functionally affect endothelial signaling for gene induction and remodeling stimuli.
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PMID:Positive signaling interactions between arsenic and ethanol for angiogenic gene induction in human microvascular endothelial cells. 1818

Rhus verniciflua Stokes (RVS) has been used in traditional Eastern Asia medicine for the treatment of gastritis and stomach cancer, although the mechanism for its biological activity remains to be elucidated. We previously established that an ethanol extract of RVS-induced G(1)-cell cycle arrest via accumulation of p27(Kip1) controlled by Skp2 reduction and apoptosis in AGS human gastric cancer cells. Here, we showed that an ethanol extract of RVS-induced apoptosis via caspase-9 activation (mitochondrial death pathway) is mediated by the loss of mitochondrial membrane potential (MMP, Deltapsi(m)) and the release of cytochrome C from the mitochondrial intermembrane space. In addition, an ethanol extract of RVS inactivated PI3K-Akt/PKB kinase in a time-dependent manner. Moreover, combined treatment of an ethanol extract of RVS and LY294002 (a PI3K inhibitor) markedly increased apoptosis compared to treatment with an ethanol extract of RVS alone. The role of PI3K-Akt/PKB in this process was confirmed by constitutive expression of inactive mutants of this kinase in AGS cells. Finally, siRNA-mediated knockdown of Akt/PKB expression resulted in a significant reduction in AGS cell proliferation. Taken together, these results suggest that an ethanol extract of RVS induces apoptosis via a mitochondrial death pathway in human gastric cancer cells, but not in normal cells, and inhibition of the PI3K-Akt/PKB pathway enhanced the mitochondrial death pathway.
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PMID:Inhibition of the PI3K-Akt/PKB survival pathway enhanced an ethanol extract of Rhus verniciflua Stokes-induced apoptosis via a mitochondrial pathway in AGS gastric cancer cell lines. 1837 93

A highly sensitive quantification method of aldosterone by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) was investigated in a positive mode using recently developed picolinyl derivatization. Aldosterone was smoothly and quantitatively converted to the ethyl ether-picolinyl derivative by treatment with HCl-ethanol followed by the esterification with picolinic acid in the presence of 2-methyl-6-nitrobenzoic anhydride and 4-dimethylaminopyridine. The positive ion-ESI mass spectrum of the ethyl ether-picolinyl derivative was characterized by an appearance of protonated molecule ([M+H](+)) as a base peak. The ethyl ether-picolinyl derivatization gave a successful result in a separation of aldosterone from corticosterone, dehydrocorticosterone and cortexolone, and also provided an approximately 10-fold higher ESI response in the positive-LC-ESI-MS/MS (selected reaction monitoring; SRM) when compared to that of underivatized molecule (negative mode). The limit of quantification of aldosterone by SRM using ethyl ether-picolinyl derivatization (m/z 494-->m/z 448) was 1 pg/0.2 ml serum with accuracy and precision of 92.6% and 5.6%, respectively.
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PMID:Development of sensitive derivatization method for aldosterone in liquid chromatography-electrospray ionization tandem mass spectrometry of corticosteroids. 1856 39

We have developed an image-based technique for signal pathway analysis, target validation, and compound screening related to mammary epithelial cell differentiation. This technique used the advantages of optical imaging and the HC11-Lux model system. The HC11-Lux cell line is a subclone of HC11 mammary epithelial cells transfected stably with a luciferase construct of the beta-casein gene promoter (p-344/-1betac-Lux). The promoter activity was imaged optically in real time following lactogenic induction. The imaging signal intensity was closely correlated with that measured using a luminometer following protein extraction (R=0.99, P<0.0001) and consistent with the messenger RNA (mRNA) level of the endogenous beta -casein gene. Using this technique, we examined the roles of JAK2/Stat5A, Raf-1/MEK/MAKP, and PI3K/Akt signal pathways with respect to differentiation. The imaging studies showed that treatment of the cells with epidermal growth factor (EGF), AG490 (JAK2-specific inhibitor), and LY294002 (PI3K-specific inhibitor) blocked lactogenic differentiation in a dose-dependent manner. PD98059 (MEK-specific inhibitor) could reverse EGF-mediated differentiation arrest. These results indicate that these pathways are essential in cell differentiation. This simple, sensitive, and reproducible technique permits visualization and real-time evaluation of the molecular events related to milk protein production. It can be adopted for high-throughput screening of small molecules for their effects on mammary epithelial cell growth, differentiation, and carcinogenesis.
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PMID:Image-based evaluation of the molecular events underlying HC11 mammary epithelial cell differentiation. 1872 92

Cadmium, lead and copper were determined in synthetic sea-water, drinking water and the NBS 1643b Trace Elements in Water standard reference material at mug/l. levels by flame atomic-absorption spectrometry after on-line preconcentration by sorbent extraction with a flow-injection system. Bonded silica with octadecyl functional groups packed in a micro column of 100 mul capacity was used to collect diethylammonium diethyldithiocarbamate complexes of the heavy metals in the aqueous samples. The sample loading time was 20 sec at a flow-rate of 3.3 ml/min. Ethanol or methanol was used to elute the adsorbed analytes into the spectrometer. The sample loading rate, elution rate and pH were optimized. Enrichment factors of 19-25 for Cd, Pb and Cu were achieved at sampling frequencies of 120/hr with precisions of 1.4, 1.0 and 1.3% rsd (n = 11), respectively. The detection limits (3sigma) for Cd, Pb and Cu were 0.3, 3 and 0.2 mug/l., respectively. Determination of Cd, Pb and Cu in NBS SRM 1643b showed good agreement with the certified values. Recoveries of Cd and Pb added to sea-water were 95 and 102%, respectively.
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PMID:Determination of cadmium, lead and copper in water samples by flame atomic-absorption spectrometry with preconcentration by flow-injection on-line sorbent extraction. 1896 93


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