Daniele Marciano - Academia.edu (original) (raw)
Papers by Daniele Marciano
Journal of Fluorescence, 2010
Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluo... more Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluorescence intensity, broad excitation band and emission diameter dependency. These unique spectroscopic characterizations make q-dots excellent candidates for new fluorescent labels in multi-chromatic analysis, such as Flow-Cytometry (FCM). In this work we shall present new possibilities of multi-labeling and multiplex analysis of pathogenic bacteria, by Flow-Cytometry (FCM) analysis and new specific IgG-q-dots conjugates. We have prepared specific conjugates against B. anthracis spores (q-dots585-IgGalphaB. anthracis and q-dots655-IgGalphaB.anthracis). These conjugates enabled us to achieve double staining of B. anthracis spores which improve the FCM analysis specificity versus control Bacillus spores. Moreover, multiplexed analysis of B. anthracis spores and Y. pestis bacteria was achieved by using specific antibodies labeled with different q-dots to obtain: q-dots585-IgGalphaB. anthracis and q-dots655-IgGalphaY.pestis, each characterized by its own emission peak as a marker. Specific and sensitive multiplex analysis for both pathogens has been achieved, down to 10(3) bacteria per ml in the sample.
Cheminform, 1991
ChemInform, 1991
ChemInform, 1991
An effective synthesis of tricyclic bimanes (p(C,)-syn-(CHz,Rl)B, RI = CH3 or Cl)) (3a-g, n = 1,2... more An effective synthesis of tricyclic bimanes (p(C,)-syn-(CHz,Rl)B, RI = CH3 or Cl)) (3a-g, n = 1,2,3) from bis-acid chlorides via bis-3-keto esters and bis-pyrazolinones is described. The success of the synthesis is strong support for the previously proposed mechanism of bimane formation, via a diazacyclopentadienone and a diazoketene. Crystal structures for three chloro derivatives ( 3 W , n = 1,2,3) reveal that the bimane dihedral ring angle and crystal packing details vary with the size of the third ring. Other spectroscopic properties (IR, UV, and NMR) vary with dihedral angle.
ChemInform, 1991
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Bioorganic & Medicinal Chemistry Letters, 1997
Inhibitors of a prenylated protein methyltransferase were synthesized and evaluated. S-farnesyl-5... more Inhibitors of a prenylated protein methyltransferase were synthesized and evaluated. S-farnesyl-5-fluorothiosalicylic acid and the 5-chloro analog (but not the 4-fluoro, 4-chloro or 3-chloro analogs) were potent inhibitors, as was the parent compound S-farnesyl thiosalicylic acid (FTS), whose methyl ester was far less active. S-geranyl and S-geranylgeranyl thiosalicylic acids were more than ten times less potent than FTS.
Biochimica Et Biophysica Acta-molecular Basis of Disease, 1998
The carboxy terminal S-farnesylcysteine of Ras oncoproteins is required for their membrane anchor... more The carboxy terminal S-farnesylcysteine of Ras oncoproteins is required for their membrane anchorage and transforming activities. We showed previously that S-farnesylthiosalicylic acid (FTS) affects the membrane anchorage of activated H-Ras in EJ cells and inhibits their growth. We report here on structural elements in S-prenyl derivatives that specifically inhibit the growth of EJ cells, but not of untransformed Rat-1 cells.
Neuroscience Letters
The nicotinic acetylcholine receptor (AChR) is a ligand gated ion channel activated upon binding ... more The nicotinic acetylcholine receptor (AChR) is a ligand gated ion channel activated upon binding of ACh. D-neurotoxins, in particular Dbungarotoxin (D-BTX), bind strongly to AChR and inhibit the binding of ACh. We have been investigating AChRs from animal species (such as the snake and mongoose) that are resistant to D-BTX, in order to elucidate the molecular basis of this resistance. We cloned and characterized the D-subunits of muscle (D 1 ) and neuronal (D 7 ) AChR from the mongoose. In the muscle AChR D-subunit there are amino acid substitutions at four key positions in the ligand binding region. These substitutions determine the resistance of the mongoose to D-BTX. Expression of the mongoose α-subunit together with the rat E, J and G subunits in Xenopus oocytes, results in mongoose/rat AChR hybrid channels that bind D-BTX 200 times less than the rat receptor, and exhibit a higher affinity to ACh. The decreased affinity of the mongoose AChR for D-BTX, together with the increased affinity for ACh, contribute to the toxin resistance of the mongoose. In investigating the mongoose neuronal AChR D 7 -subunit we have observed that, unlike the muscle D-subunit, there are no significant changes in nucleotide and amino acid sequence at the binding site region of the mongoose neuronal AChR, as compared with sequences of toxin-sensitive animals, and that mongoose D 7 binds D-BTX. It appears that there was no evolutionary pressure on the neuronal AChR to be altered, as is the case with the muscle AChR, since D-BTX does not cross the blood brain barrier.
Biochemistry
Membrane anchorage of Ras oncoproteins, required for transforming activity, depends on their carb... more Membrane anchorage of Ras oncoproteins, required for transforming activity, depends on their carboxy-terminal farnesylcysteine. We previously showed that S-trans,trans-farnesylthiosalicylic acid (FTS), a synthetic farnesylcysteine mimetic, inhibits growth of ErbB2- and Ras-transformed cells, but not of v-Raf-transformed cells, suggesting that FTS interferes specifically with Ras functions. Here we demonstrate that FTS dislodges Ras from membranes of H-Ras-transformed (EJ) cells, facilitating its degradation and decreasing total cellular Ras. The dislodged Ras that was transiently present in the cytosol was degraded relatively rapidly, causing a decrease of up to 80% in total cellular Ras. The half-life of Ras was 10 +/- 4 h in FTS-treated EJ cells and 27 +/- 4 h in controls. The dislodgment of membrane Ras and decrease in total cellular Ras were dose-dependent: 50% of the effects occurred at 10-15 microM, comparable to concentrations (7-10 microM) required for 50% growth inhibition ...
The Journal of Organic Chemistry, 2015
The effects solvents have on fluoride-promoted heterogeneous hydrolysis and alcoholysis of variou... more The effects solvents have on fluoride-promoted heterogeneous hydrolysis and alcoholysis of various organo-phosphorus (OP) compounds on the surface of KF/Al2O3 are described. Solid-state magic angle spinning NMR analyses and SEM microscopy have shown that not only is the identity of the solvent important in these reactions but also its quantity. That is, minimal solvent amounts are favored and much more effective in such solid-supported reactions (and maybe generally) than those featuring solvent-free or excess solvent (>50 wt %) conditions. The addition of a minute quantity of the correct solvent (3-10 wt %, molar equivalent scale) avoids reagents leaching from the matrix, permits mobility (mass transport) of the reaction components and ensures their very high local concentration in close proximity to the solid-support large porous surface area. Accordingly, significant acceleration of reactions rates by orders of magnitude is obtained. Fascinatingly, even challenging phosphoesters with poor leaving groups, which were found to be very stable in the presence of solvent-free KF/Al2O3 or wetted with excess water, were efficiently hydrolyzed with a minute amount of this solvent.
... (22) Fahey, R. C.; Newton, GL; Dorian, R.; Kosower, E. M. Anal. (23) Newton, GL; Dorian, R.; ... more ... (22) Fahey, R. C.; Newton, GL; Dorian, R.; Kosower, E. M. Anal. (23) Newton, GL; Dorian, R.; Fahey, RC Anal. Biochem. ... 1987, (26) (a) Matthews, 1. T. WJ Immunol. Methods 1982,51,307-309 Matthews, I. T. W.; Decker, R. S.; Knight, CG Biochem. J. 1981, 611-617. ...
Neurobiology of Aging, 1996
European Journal of Biochemistry, 1996
Effects of the farnesylcysteine mimetic, farnesylthiosalicylate on the activation of myeloid cell... more Effects of the farnesylcysteine mimetic, farnesylthiosalicylate on the activation of myeloid cells were studied. In dimethyl-sulfoxide-differentiated HL60 cells and in human neutrophils farnesylthiosalicylate (G20 pM) dose-dependently elevated cytosolic Ca" concentrations, suggesting phospholipase-c-mediated release of the ion from intracellular stores. In human neutrophils, in addition to the production of inositol trisphosphate, farnesylthiosalicylate induced activation of the NADPH oxidase and translocation of the cytosolic oxidase components p47-phox and p67-phox to the membrane. The calcium signal, inositol-trisphosphate production and superoxide generation elicited by farnesylthiosalicylate were partially blocked by treatment of the cells with pertussis toxin, consistent with participation of pertussistoxin-sensitive and pertussis-toxin-resistant elements. In HL60 cells, farnesylthiosalicylate ( c 2 0 pM) did not activate NADPH oxidase but dose-dependently augmented PMA-elicited activity of the enzyme. This effect was resistant to pertussis-toxin treatment. In vitro augmentation of PKC-mediated phosphorylation of histone and cytosolic p47-phox by farnesylthiosalicylate and the finding that downregulation of PKC abrogated potentiation of NADPH oxidase activity by farnesylthiosalicylate were compatible with the involvement of PKC in the response of HL60 cells to farnesylthiosalicylate. It is suggested that the effects of farnesylthiosalicylate on myeloid cells reflect interaction of the analog with prenylcysteine-docking sites on cellular signaling elements.
Postharvest Biology and Technology, 1998
Incidences of superficial scald and other storage disorders were recorded in two seasons, 1994 an... more Incidences of superficial scald and other storage disorders were recorded in two seasons, 1994 and 1995, for 'Starkrimson', a scald-susceptible strain of 'Delicious' apples (Malus domestica Borkh.) stored at 0°C in air for 6 months and in 0.7% O 2 +1.0% CO 2 for 6 and 8 months at eight North American locations. Fruit from British 1994 -95) and Oregon (OR; 1994-95), which were picked near starch index 2.0 on a 0 -9 scale, were scald-free after storage in 0.7% O 2 +1.0% CO 2 even though air-stored fruit had severe scald incidences. Low O 2 storage reduced, but did not eliminate scald on California (CA), Nova Scotia (NS; stored in 0% CO 2 ), PA and Washington (WA) fruit in 1994, and NY fruit in 1995. However, 0.7% O 2 was ineffective in controlling scald on NS (stored in 0% CO 2 ) and WA fruit in 1995. Immature fruit, delayed O 2 reduction, and failure to maintain the 0.7% O 2 + 1.0% CO 2 atmosphere during the entire storage period decreased the effectiveness of 0.7% O 2 storage for scald control. Fruit from some locations were * Corresponding
Oncogene, 1999
Constitutively active Ras proteins, their regulatory components, and overexpressed tyrosine kinas... more Constitutively active Ras proteins, their regulatory components, and overexpressed tyrosine kinase receptors that activate Ras, are frequently associated with cell transformation in human tumors. This suggests that functional Ras antagonists may have anti-tumor activity. Studies in rodent ®broblasts have shown that S-trans, transfarnesylthiosalicylic acid (FTS) acts as a rather speci®c nontoxic Ras antagonist, dislodging Ras from its membrane anchorage domains and accelerating its degradation. FTS is not a farnesyltransferase inhibitor, and does not aect Ras maturation. Here we demonstrate that FTS also acts as a functional Ras antagonist in human pancreatic cell lines that express activated K-Ras (Panc-1 and MiaPaCa-2). In Panc-1 cells, FTS at a concentration of 25 ± 100 mM reduced the amount of Ras in a dose-dependent manner and interfered with serumdependent and epidermal growth factor-stimulated ERK activation, thus inhibiting both anchorage-dependent and anchorage-independent growth of Panc-1 cells in vitro. FTS also inhibited tumor growth in Panc-1 xenografted nude mice, apparently without systemic toxicity. Daily FTS treatment (5 mg/kg intraperitoneally) in mice with tumors (mean volume 0.07 cm 3 ) markedly decreased tumor growth (after treatment for 18 days, tumor volume had increased by only 23+30-fold in the FTStreated group and by 127+66-fold in controls). These ®ndings suggest that FTS represents a new class of functional Ras antagonists with potential therapeutic value.
Life Sciences, 1997
Human SH-SY5Y neuroblastoma cells have been utilized to investigate the mechanism whereby agonist... more Human SH-SY5Y neuroblastoma cells have been utilized to investigate the mechanism whereby agonist occupancy of muscarinic receptors elicits an increase in the tyrosine phosphorylation of focal adhesion kinase (~125~~~). SH-SY5Y cells express muscarinic cholinergic receptors (mAChRs) of predominantly the m3 subtype, which are robustly coupled to phosphoinositide (PPI) hydrolysis and Ca2+ homeostasis. The addition of oxotremorine-M (0x0-M) resulted in an increased tyrosine phosphorylation of ~125 FAK that was maximal by 10 minutes and persisted for 2 hours. HaIf-maximal phosphorylation of ~125~AK was observed at an oxo-M concentration of approximately 10 PM. OxoM-stimulated ~125~~~ phosphorylation was independent of the production of phospholipase C (PLC)-derived second messengers, integrinextracellular matrix interactions, and cell attachment, but required an intact actin microfilament network m8AChR-mediated ~125 F*K phosphorylation was attenuated by the addition of micromolar concentrations of wortmannin, a putative inhibitor of both phosphatidylinositol (PI) 3'kinase and PI 4'-kinase. Wortmannin inhibited both receptor-stimulated ~125~~~ phosphorylation and PPI hydrolysis with similar IC50 values of approximately 1 PM. These results suggest that although the formation of PLC-derived second messengers is not a prerequisite for p125P*K phosphorylation following mAChR activation, inositol phospholipid turnover may nonetheless play a pivotal role in events that initiate the tyrosine phosphorylation of ~125~~~. (Supporfed by NIH NS 23831 and NIMH MH 46252.1
Journal of the American Chemical Society, 1990
Journal of the American Chemical Society, 1990
lapping doublets centered at ca. 0.90 and 0.86 and 0.84 (9 H, J = ca.
Journal of Fluorescence, 2010
Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluo... more Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluorescence intensity, broad excitation band and emission diameter dependency. These unique spectroscopic characterizations make q-dots excellent candidates for new fluorescent labels in multi-chromatic analysis, such as Flow-Cytometry (FCM). In this work we shall present new possibilities of multi-labeling and multiplex analysis of pathogenic bacteria, by Flow-Cytometry (FCM) analysis and new specific IgG-q-dots conjugates. We have prepared specific conjugates against B. anthracis spores (q-dots585-IgGalphaB. anthracis and q-dots655-IgGalphaB.anthracis). These conjugates enabled us to achieve double staining of B. anthracis spores which improve the FCM analysis specificity versus control Bacillus spores. Moreover, multiplexed analysis of B. anthracis spores and Y. pestis bacteria was achieved by using specific antibodies labeled with different q-dots to obtain: q-dots585-IgGalphaB. anthracis and q-dots655-IgGalphaY.pestis, each characterized by its own emission peak as a marker. Specific and sensitive multiplex analysis for both pathogens has been achieved, down to 10(3) bacteria per ml in the sample.
Cheminform, 1991
ChemInform, 1991
ChemInform, 1991
An effective synthesis of tricyclic bimanes (p(C,)-syn-(CHz,Rl)B, RI = CH3 or Cl)) (3a-g, n = 1,2... more An effective synthesis of tricyclic bimanes (p(C,)-syn-(CHz,Rl)B, RI = CH3 or Cl)) (3a-g, n = 1,2,3) from bis-acid chlorides via bis-3-keto esters and bis-pyrazolinones is described. The success of the synthesis is strong support for the previously proposed mechanism of bimane formation, via a diazacyclopentadienone and a diazoketene. Crystal structures for three chloro derivatives ( 3 W , n = 1,2,3) reveal that the bimane dihedral ring angle and crystal packing details vary with the size of the third ring. Other spectroscopic properties (IR, UV, and NMR) vary with dihedral angle.
ChemInform, 1991
ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Bioorganic & Medicinal Chemistry Letters, 1997
Inhibitors of a prenylated protein methyltransferase were synthesized and evaluated. S-farnesyl-5... more Inhibitors of a prenylated protein methyltransferase were synthesized and evaluated. S-farnesyl-5-fluorothiosalicylic acid and the 5-chloro analog (but not the 4-fluoro, 4-chloro or 3-chloro analogs) were potent inhibitors, as was the parent compound S-farnesyl thiosalicylic acid (FTS), whose methyl ester was far less active. S-geranyl and S-geranylgeranyl thiosalicylic acids were more than ten times less potent than FTS.
Biochimica Et Biophysica Acta-molecular Basis of Disease, 1998
The carboxy terminal S-farnesylcysteine of Ras oncoproteins is required for their membrane anchor... more The carboxy terminal S-farnesylcysteine of Ras oncoproteins is required for their membrane anchorage and transforming activities. We showed previously that S-farnesylthiosalicylic acid (FTS) affects the membrane anchorage of activated H-Ras in EJ cells and inhibits their growth. We report here on structural elements in S-prenyl derivatives that specifically inhibit the growth of EJ cells, but not of untransformed Rat-1 cells.
Neuroscience Letters
The nicotinic acetylcholine receptor (AChR) is a ligand gated ion channel activated upon binding ... more The nicotinic acetylcholine receptor (AChR) is a ligand gated ion channel activated upon binding of ACh. D-neurotoxins, in particular Dbungarotoxin (D-BTX), bind strongly to AChR and inhibit the binding of ACh. We have been investigating AChRs from animal species (such as the snake and mongoose) that are resistant to D-BTX, in order to elucidate the molecular basis of this resistance. We cloned and characterized the D-subunits of muscle (D 1 ) and neuronal (D 7 ) AChR from the mongoose. In the muscle AChR D-subunit there are amino acid substitutions at four key positions in the ligand binding region. These substitutions determine the resistance of the mongoose to D-BTX. Expression of the mongoose α-subunit together with the rat E, J and G subunits in Xenopus oocytes, results in mongoose/rat AChR hybrid channels that bind D-BTX 200 times less than the rat receptor, and exhibit a higher affinity to ACh. The decreased affinity of the mongoose AChR for D-BTX, together with the increased affinity for ACh, contribute to the toxin resistance of the mongoose. In investigating the mongoose neuronal AChR D 7 -subunit we have observed that, unlike the muscle D-subunit, there are no significant changes in nucleotide and amino acid sequence at the binding site region of the mongoose neuronal AChR, as compared with sequences of toxin-sensitive animals, and that mongoose D 7 binds D-BTX. It appears that there was no evolutionary pressure on the neuronal AChR to be altered, as is the case with the muscle AChR, since D-BTX does not cross the blood brain barrier.
Biochemistry
Membrane anchorage of Ras oncoproteins, required for transforming activity, depends on their carb... more Membrane anchorage of Ras oncoproteins, required for transforming activity, depends on their carboxy-terminal farnesylcysteine. We previously showed that S-trans,trans-farnesylthiosalicylic acid (FTS), a synthetic farnesylcysteine mimetic, inhibits growth of ErbB2- and Ras-transformed cells, but not of v-Raf-transformed cells, suggesting that FTS interferes specifically with Ras functions. Here we demonstrate that FTS dislodges Ras from membranes of H-Ras-transformed (EJ) cells, facilitating its degradation and decreasing total cellular Ras. The dislodged Ras that was transiently present in the cytosol was degraded relatively rapidly, causing a decrease of up to 80% in total cellular Ras. The half-life of Ras was 10 +/- 4 h in FTS-treated EJ cells and 27 +/- 4 h in controls. The dislodgment of membrane Ras and decrease in total cellular Ras were dose-dependent: 50% of the effects occurred at 10-15 microM, comparable to concentrations (7-10 microM) required for 50% growth inhibition ...
The Journal of Organic Chemistry, 2015
The effects solvents have on fluoride-promoted heterogeneous hydrolysis and alcoholysis of variou... more The effects solvents have on fluoride-promoted heterogeneous hydrolysis and alcoholysis of various organo-phosphorus (OP) compounds on the surface of KF/Al2O3 are described. Solid-state magic angle spinning NMR analyses and SEM microscopy have shown that not only is the identity of the solvent important in these reactions but also its quantity. That is, minimal solvent amounts are favored and much more effective in such solid-supported reactions (and maybe generally) than those featuring solvent-free or excess solvent (>50 wt %) conditions. The addition of a minute quantity of the correct solvent (3-10 wt %, molar equivalent scale) avoids reagents leaching from the matrix, permits mobility (mass transport) of the reaction components and ensures their very high local concentration in close proximity to the solid-support large porous surface area. Accordingly, significant acceleration of reactions rates by orders of magnitude is obtained. Fascinatingly, even challenging phosphoesters with poor leaving groups, which were found to be very stable in the presence of solvent-free KF/Al2O3 or wetted with excess water, were efficiently hydrolyzed with a minute amount of this solvent.
... (22) Fahey, R. C.; Newton, GL; Dorian, R.; Kosower, E. M. Anal. (23) Newton, GL; Dorian, R.; ... more ... (22) Fahey, R. C.; Newton, GL; Dorian, R.; Kosower, E. M. Anal. (23) Newton, GL; Dorian, R.; Fahey, RC Anal. Biochem. ... 1987, (26) (a) Matthews, 1. T. WJ Immunol. Methods 1982,51,307-309 Matthews, I. T. W.; Decker, R. S.; Knight, CG Biochem. J. 1981, 611-617. ...
Neurobiology of Aging, 1996
European Journal of Biochemistry, 1996
Effects of the farnesylcysteine mimetic, farnesylthiosalicylate on the activation of myeloid cell... more Effects of the farnesylcysteine mimetic, farnesylthiosalicylate on the activation of myeloid cells were studied. In dimethyl-sulfoxide-differentiated HL60 cells and in human neutrophils farnesylthiosalicylate (G20 pM) dose-dependently elevated cytosolic Ca" concentrations, suggesting phospholipase-c-mediated release of the ion from intracellular stores. In human neutrophils, in addition to the production of inositol trisphosphate, farnesylthiosalicylate induced activation of the NADPH oxidase and translocation of the cytosolic oxidase components p47-phox and p67-phox to the membrane. The calcium signal, inositol-trisphosphate production and superoxide generation elicited by farnesylthiosalicylate were partially blocked by treatment of the cells with pertussis toxin, consistent with participation of pertussistoxin-sensitive and pertussis-toxin-resistant elements. In HL60 cells, farnesylthiosalicylate ( c 2 0 pM) did not activate NADPH oxidase but dose-dependently augmented PMA-elicited activity of the enzyme. This effect was resistant to pertussis-toxin treatment. In vitro augmentation of PKC-mediated phosphorylation of histone and cytosolic p47-phox by farnesylthiosalicylate and the finding that downregulation of PKC abrogated potentiation of NADPH oxidase activity by farnesylthiosalicylate were compatible with the involvement of PKC in the response of HL60 cells to farnesylthiosalicylate. It is suggested that the effects of farnesylthiosalicylate on myeloid cells reflect interaction of the analog with prenylcysteine-docking sites on cellular signaling elements.
Postharvest Biology and Technology, 1998
Incidences of superficial scald and other storage disorders were recorded in two seasons, 1994 an... more Incidences of superficial scald and other storage disorders were recorded in two seasons, 1994 and 1995, for 'Starkrimson', a scald-susceptible strain of 'Delicious' apples (Malus domestica Borkh.) stored at 0°C in air for 6 months and in 0.7% O 2 +1.0% CO 2 for 6 and 8 months at eight North American locations. Fruit from British 1994 -95) and Oregon (OR; 1994-95), which were picked near starch index 2.0 on a 0 -9 scale, were scald-free after storage in 0.7% O 2 +1.0% CO 2 even though air-stored fruit had severe scald incidences. Low O 2 storage reduced, but did not eliminate scald on California (CA), Nova Scotia (NS; stored in 0% CO 2 ), PA and Washington (WA) fruit in 1994, and NY fruit in 1995. However, 0.7% O 2 was ineffective in controlling scald on NS (stored in 0% CO 2 ) and WA fruit in 1995. Immature fruit, delayed O 2 reduction, and failure to maintain the 0.7% O 2 + 1.0% CO 2 atmosphere during the entire storage period decreased the effectiveness of 0.7% O 2 storage for scald control. Fruit from some locations were * Corresponding
Oncogene, 1999
Constitutively active Ras proteins, their regulatory components, and overexpressed tyrosine kinas... more Constitutively active Ras proteins, their regulatory components, and overexpressed tyrosine kinase receptors that activate Ras, are frequently associated with cell transformation in human tumors. This suggests that functional Ras antagonists may have anti-tumor activity. Studies in rodent ®broblasts have shown that S-trans, transfarnesylthiosalicylic acid (FTS) acts as a rather speci®c nontoxic Ras antagonist, dislodging Ras from its membrane anchorage domains and accelerating its degradation. FTS is not a farnesyltransferase inhibitor, and does not aect Ras maturation. Here we demonstrate that FTS also acts as a functional Ras antagonist in human pancreatic cell lines that express activated K-Ras (Panc-1 and MiaPaCa-2). In Panc-1 cells, FTS at a concentration of 25 ± 100 mM reduced the amount of Ras in a dose-dependent manner and interfered with serumdependent and epidermal growth factor-stimulated ERK activation, thus inhibiting both anchorage-dependent and anchorage-independent growth of Panc-1 cells in vitro. FTS also inhibited tumor growth in Panc-1 xenografted nude mice, apparently without systemic toxicity. Daily FTS treatment (5 mg/kg intraperitoneally) in mice with tumors (mean volume 0.07 cm 3 ) markedly decreased tumor growth (after treatment for 18 days, tumor volume had increased by only 23+30-fold in the FTStreated group and by 127+66-fold in controls). These ®ndings suggest that FTS represents a new class of functional Ras antagonists with potential therapeutic value.
Life Sciences, 1997
Human SH-SY5Y neuroblastoma cells have been utilized to investigate the mechanism whereby agonist... more Human SH-SY5Y neuroblastoma cells have been utilized to investigate the mechanism whereby agonist occupancy of muscarinic receptors elicits an increase in the tyrosine phosphorylation of focal adhesion kinase (~125~~~). SH-SY5Y cells express muscarinic cholinergic receptors (mAChRs) of predominantly the m3 subtype, which are robustly coupled to phosphoinositide (PPI) hydrolysis and Ca2+ homeostasis. The addition of oxotremorine-M (0x0-M) resulted in an increased tyrosine phosphorylation of ~125 FAK that was maximal by 10 minutes and persisted for 2 hours. HaIf-maximal phosphorylation of ~125~AK was observed at an oxo-M concentration of approximately 10 PM. OxoM-stimulated ~125~~~ phosphorylation was independent of the production of phospholipase C (PLC)-derived second messengers, integrinextracellular matrix interactions, and cell attachment, but required an intact actin microfilament network m8AChR-mediated ~125 F*K phosphorylation was attenuated by the addition of micromolar concentrations of wortmannin, a putative inhibitor of both phosphatidylinositol (PI) 3'kinase and PI 4'-kinase. Wortmannin inhibited both receptor-stimulated ~125~~~ phosphorylation and PPI hydrolysis with similar IC50 values of approximately 1 PM. These results suggest that although the formation of PLC-derived second messengers is not a prerequisite for p125P*K phosphorylation following mAChR activation, inositol phospholipid turnover may nonetheless play a pivotal role in events that initiate the tyrosine phosphorylation of ~125~~~. (Supporfed by NIH NS 23831 and NIMH MH 46252.1
Journal of the American Chemical Society, 1990
Journal of the American Chemical Society, 1990
lapping doublets centered at ca. 0.90 and 0.86 and 0.84 (9 H, J = ca.