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1.
Br J Cancer ; 99(8): 1216-20, 2008 Oct 21.
Article in English | MEDLINE | ID: mdl-18854823

ABSTRACT

The objective of this retrospective study was to determine the efficacy of adjuvant hysterectomy for treatment of residual disease in cervical carcinoma treated with radiation therapy. Between 1971 and 1996, 1590 patients with carcinoma of the uterine cervix (stages I-IIIb) were treated with radiation therapy. Three months after completion of radiation therapy, the status of local control was investigated, and total abdominal hysterectomy was performed in cases in which central residual disease existed in the cervix. Of the 1590 patients, residual disease was identified in 162 patients. Among these patients, 35 showed an absence of distant metastasis or lateral parametrial invasion and underwent hysterectomy. The overall 5- and 10-year survival rates for these patients were 68.6 and 65.7%, respectively. There was no significant difference in survival between patients with squamous cell carcinoma and those with non-squamous cell carcinoma or between patients with stage I/II carcinoma and those with stage III carcinoma. With respect to treatment-related morbidity, five (14.3%) patients suffered grade III or IV complications after hysterectomy. Adjuvant hysterectomy is an effective addition to radiation therapy in the treatment of cervical cancer, even in patients with stage III disease and in those with non-squamous cell carcinoma.


Subject(s)
Uterine Cervical Neoplasms/radiotherapy , Uterine Cervical Neoplasms/surgery , Adult , Aged , Combined Modality Therapy , Female , Humans , Hysterectomy , Kaplan-Meier Estimate , Middle Aged , Neoplasm, Residual , Postoperative Complications/epidemiology , Retrospective Studies , Uterine Cervical Neoplasms/mortality
2.
Biochim Biophys Acta ; 1077(2): 192-6, 1991 Apr 08.
Article in English | MEDLINE | ID: mdl-2015292

ABSTRACT

The sesquiterpene antibiotic koningic acid (heptelidic acid) has been previously demonstrated to modify glyceraldehyde-3-phosphate dehydrogenase in specific manner, probably by binding to the sulfhydryl residue at the active site of the enzyme (Sakai, K., Hasumi, K. and Endo, A. (1988) Biochim. Biophys. Acta 952, 297-303). Rabbit muscle glyceraldehyde-3-phosphate dehydrogenase labeled with [3H]koningic acid was digested with trypsin. Reverse-phase HPLC revealed that the label is associated exclusively with a tryptic peptide having 17 amino acid residues. Microsequencing and fast atom bombardment mass spectrometry demonstrated that the peptide has the sequence Ile-Var-Ser-Asn-Ala-Ser-Cys-Thr-Thr-Asn-Cys-Leu-Ala-Pro-Leu-Ala-Lys. In comparison to the amino acid sequence of glyceraldehyde-3-phosphate dehydrogenase from other species, this peptide is in a highly conserved region and is part of the active site of the enzyme. The cysteine residue corresponding to the Cys-149 in the pig muscle enzyme, which has been shown to be an essential residue for the enzyme activity, was shown to be the site modified by koningic acid. Structural analyses of the reaction product of koningic acid and L-cysteine suggested that the epoxide of koningic acid reacts with the sulfhydryl group of cysteine residue, resulting in a thioether.


Subject(s)
Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Muscles/enzymology , Amino Acids/analysis , Animals , Chromatography, High Pressure Liquid , Magnetic Resonance Spectroscopy , Mass Spectrometry , Rabbits , Sesquiterpenes/chemistry
3.
Biochim Biophys Acta ; 1258(1): 70-4, 1995 Aug 24.
Article in English | MEDLINE | ID: mdl-7654783

ABSTRACT

Plasma cholesteryl ester transfer protein (CETP), which mediates the transfer and exchange of neutral lipids (cholesteryl esters (CE) and triglycerides (TG) and phospholipids between plasma lipoproteins, plays an essential role in reverse cholesterol transport system. We have found that a fungal metabolite, stachybotramide, modulates the activity of CETP. Stachybotramide stimulated the [14C]CE transfer from high density lipoprotein (HDL) to very low density lipoprotein (VLDL) and low density lipoprotein (LDL) by 1.3- to 1.5-fold at 0.2-0.5 mM. This stimulation was abolished in the presence of anti-CETP antibody. On the other hand, the transfer of [14C]CE from LDL and VLDL to HDL was slightly reduced by stachybotramide at 0.5 mM. Unlike the transfer of [14C]CE, the transfer of [3H]TG from HDL was not significantly affected by stachybotramide. These results suggest that stachybotramide preferentially stimulate the CETP-mediated transfer of CE from HDL to both VLDL and LDL.


Subject(s)
Benzofurans/pharmacology , Carrier Proteins/metabolism , Cholesterol Esters/blood , Glycoproteins , Spiro Compounds/pharmacology , Stachybotrys , Antibodies, Monoclonal/pharmacology , Biological Transport , Carrier Proteins/immunology , Cholesterol Ester Transfer Proteins , Humans , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Lipoproteins, VLDL/blood , Triglycerides/blood
4.
Biochim Biophys Acta ; 1167(3): 303-6, 1993 Apr 23.
Article in English | MEDLINE | ID: mdl-8481392

ABSTRACT

The antibiotic helvolic acid inhibited cholesteryl ester accumulation in macrophage J774 treated with oxidized low-density lipoprotein (LDL) at a concentration of 50-350 microM. The agent reduced oxidized 125I-LDL degradation and [14C]oleate incorporation into cholesteryl ester. In a cell-free assay, ATP-dependent acidification of endosomes and lysosomes was significantly inhibited by 35 microM helvolic acid, suggesting that this activity accounts for the inhibition of oxidized LDL metabolism in the macrophages.


Subject(s)
Fusidic Acid/analogs & derivatives , Lipoproteins, LDL/metabolism , Macrophages/metabolism , Adenosine Triphosphate/metabolism , Animals , Carbon Radioisotopes , Cell Line/drug effects , Cell-Free System/metabolism , Cholesterol Esters/metabolism , Fusidic Acid/pharmacology , Hydrogen-Ion Concentration , Iodine Radioisotopes , Leucine/metabolism , Macrophages/drug effects , Mice , Oleic Acid , Oleic Acids/metabolism , Oxidation-Reduction , Tritium
5.
Biochim Biophys Acta ; 952(3): 297-303, 1988 Feb 10.
Article in English | MEDLINE | ID: mdl-3337830

ABSTRACT

Koningic acid, a sesquiterpene antibiotic, is a specific inhibitor of the enzyme glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC 1.2.1.12). In the presence of 3 mM of NAD+, koningic acid irreversibly inactivated the enzyme in a time-dependent manner. The pseudo-first-order rate constant for inactivation (kapp) was dependent on koningic acid concentration in saturate manner, indicating koningic acid and enzyme formed a reversible complex prior to the formation of an inactive, irreversible complex; the inactivation rate (k 3) was 5.5.10(-2) s-1, with a dissociation constant for inactivation (Kinact) of 1.6 microM. The inhibition was competitive against glyceraldehyde 3-phosphate with a Ki of 1.1 microM, where the Km for glyceraldehyde 3-phosphate was 90 microM. Koningic acid inhibition was uncompetitive with respect to NAD+. The presence of NAD+ accelerated the inactivation. In its absence, the charcoal-treated NAD+-free enzyme showed a 220-fold decrease in apparent rate constant for inactivation, indicating that koningic acid sequentially binds to the enzyme next to NAD+. The enzyme, a tetramer, was inactivated when maximum two sulfhydryl groups, possibly cysteine residues at the active sites of the enzyme, were modified by the binding of koningic acid. These observations demonstrate that koningic acid is an active-site-directed inhibitor which reacts predominantly with the NAD+-enzyme complex.


Subject(s)
Glyceraldehyde-3-Phosphate Dehydrogenases/antagonists & inhibitors , Muscles/enzymology , Animals , Enzyme Activation/drug effects , Enzyme Reactivators/pharmacology , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Protein Binding/drug effects , Rabbits , Sesquiterpenes/pharmacology , Substrate Specificity , Time Factors
6.
Biochim Biophys Acta ; 1083(3): 289-97, 1991 Jun 03.
Article in English | MEDLINE | ID: mdl-2049394

ABSTRACT

CR200 cells, a compactin-resistant clone of mouse FM3A cells, overaccumulate 3-hydroxy-3-methylglutaryl coenzyme A reductase. The elevated reductase activity is not regulated normally by low-density lipoprotein, mevalonate and 25-hydroxycholesterol. The amounts of reductase protein and mRNA were elevated in CR200 cells by 40- to 60-fold, as compared to those in parental FM3A cells and the rate of reductase transcription and the number of copies of reductase gene were increased in CR200 cells by 20- to 50-fold. In the parental cells, mevalonate and 25-hydroxycholesterol suppressed reductase transcription by greater than 90%, while that in the mutant cells was suppressed by only 20-50%, suggesting a regulatory alteration in the gene transcription in CR200 cells. When CR200 cells were grown for 10-20 weeks in the absence of compactin, levels of the gene amplification were reduced from approx. 50-fold to approx. 2-fold, along with a marked decrease in reductase activity and compactin-resistance of the cells. While the gene amplification was unstable, minute chromosomes were not seen in the cells and centrifugal fractionation and in situ analysis demonstrated that the amplified reductase gene was present on 2-3 chromosomes in the pseudotetraploidal CR200 cells having approx. 78 chromosomes. From these results it was concluded that the amplified reductase gene, which is responsible for overaccumulation of reductase, is located on chromosomes but is unstable in CR200 cells.


Subject(s)
Gene Amplification/drug effects , Hydroxymethylglutaryl CoA Reductases/genetics , Animals , Cell Fractionation , Cell Line/drug effects , Cell Line/enzymology , DNA Probes , Drug Resistance , Hydroxymethylglutaryl CoA Reductases/biosynthesis , Karyotyping , Lovastatin/analogs & derivatives , Lovastatin/pharmacology , Metaphase , Mice , Nucleic Acid Hybridization , RNA, Messenger/analysis
7.
Biochim Biophys Acta ; 1172(1-2): 43-8, 1993 Feb 20.
Article in English | MEDLINE | ID: mdl-8439569

ABSTRACT

Koningic acid inhibits glyceraldehyde-3-phosphate dehydrogenase (GAPDH) by binding to the SH group in the active center. The fungus Trichoderma koningii, the producer of koningic acid, contains two GAPDH isozymes (GAPDHs I and II). GAPDH I is inhibited 50% by 1.1.10(-3) M koningic acid, while GAPDH II is inhibited 50% at 6.8 x 10(-6) M. cDNAs of the two isozymes were cloned from T. koningii and their nucleotide sequences were determined. The sequence of coding region and codon usage in both clones were compared with each other and with those of the gene for Aspergillus nidulans GAPDH (enzyme activity is inhibited 50% by 2.7 x 10(-7) M koningic acid). Results indicated that GAPDH II is more closely related to A. nidulans GAPDH than GAPDH I. All essential amino acid residues, except 174 and 181, which are implicated in catalysis and binding of NAD and substrates, were conserved among A. nidulans GAPDH and GAPDHs I and II. Residues 174 and 181 are threonine in both A. nidulans GAPDH and GAPDH II, but alanine and serine, respectively, in GAPDH I. The side-chain of alanine-174 in GAPDH I can not replace threonine-174 functionally as threonine-174 side-chain forms a hydrogen bond with the catalytically essential histidine-176.


Subject(s)
Glyceraldehyde-3-Phosphate Dehydrogenases/genetics , Isoenzymes/genetics , Trichoderma/enzymology , Trichoderma/genetics , Amino Acid Sequence , Animals , Aspergillus nidulans/enzymology , Aspergillus nidulans/genetics , Base Sequence , Binding Sites , Cloning, Molecular , DNA, Fungal/genetics , DNA, Fungal/isolation & purification , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Humans , Isoenzymes/metabolism , Molecular Sequence Data , RNA, Messenger/genetics , RNA, Messenger/isolation & purification , Recombinant Proteins/metabolism , Restriction Mapping , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid , Sesquiterpenes/pharmacology
8.
Biochim Biophys Acta ; 1167(2): 155-8, 1993 Apr 07.
Article in English | MEDLINE | ID: mdl-8466943

ABSTRACT

Brefeldin A (BFA), an inhibitor of secretory pathway, enhances incorporation of radiolabeled cholesterol and oleate into cholesteryl esters in cultured cells [12]. We studied the mechanism for this effect of BFA in the macrophage J774. When incubated with 2.7 microM BFA in the absence of lipoproteins, J774 cells synthesized and accumulated 1.5- to 4-fold more cholesteryl esters than did cells which received no BFA. BFA caused neither an elevation of cholesterol synthesis, inhibition of its secretion nor changes in cholesterol transport to plasma membrane, esterification of plasma membrane cholesterol and cholesteryl ester hydrolysis. Acyl-CoA:cholesterol acyltransferase (ACAT) activity in microsomes from BFA-treated cells was 1.5- to 1.8-fold higher than that from control cells. The effect of BFA was diminished by treatment with low temperature, which is known to abolish BFA effect on Golgi formation.


Subject(s)
Anti-Bacterial Agents/pharmacology , Cyclopentanes/pharmacology , Macrophages/drug effects , Sterol O-Acyltransferase/metabolism , Acetates/metabolism , Animals , Brefeldin A , Cell Line/drug effects , Cholesterol/metabolism , Cholesterol Esters/biosynthesis , Enzyme Activation/drug effects , Macrophages/metabolism , Mice , Oleic Acid , Oleic Acids/metabolism
9.
Biochim Biophys Acta ; 1126(1): 41-8, 1992 Jun 05.
Article in English | MEDLINE | ID: mdl-1606174

ABSTRACT

Two microbial metabolites, bafilomycin B1 and destruxin E, have been found to inhibit significantly the oxidized low density lipoprotein (LDL)-induced accumulation of lipid droplets at 3 nM and 0.5 microM, respectively, in macrophage J774. The incorporation of [14C]oleate into cholesteryl esters in the cells incubated with oxidized LDL was inhibited to the same extent by the two compounds. Both compounds had no effect on the cell surface binding at 4 degrees C and the internalization of oxidized 125I-LDL as well as on the activity of acyl-CoA:cholesterol acyltransferase. However, when incubated with these compounds at 37 degrees C, receptors for oxidized LDL were partially trapped within the cell. In accordance with receptor accumulation, ATP-dependent acidification of endosomes and lysosomes was significantly inhibited by 50 nM bafilomycin B1 and 1 microM destruxin E, respectively. From these results it was concluded that the inhibition of ATP-dependent acidification of endosomes and lysosomes by bafilomycin B1 and destruxin E resulted in the reduction of oxidized LDL-induced synthesis of cholesteryl ester and thereby caused a reduced accumulation of lipid droplets in macrophage J774.


Subject(s)
Anti-Bacterial Agents/pharmacology , Depsipeptides , Fungal Proteins , Lipid Metabolism , Lipoproteins, LDL/pharmacology , Macrolides , Macrophages/metabolism , Peptides, Cyclic/pharmacology , Animals , Azo Compounds , Cell Line , Cholesterol Esters/biosynthesis , Hydrogen-Ion Concentration , Lysosomes/drug effects , Macrophages/drug effects , Mice , Sterol O-Acyltransferase/metabolism
10.
J Clin Oncol ; 16(5): 1869-78, 1998 May.
Article in English | MEDLINE | ID: mdl-9586903

ABSTRACT

PURPOSE: To evaluate the efficacy and toxicity of combination chemotherapy with bleomycin, vincristine, mitomycin, and consecutive low-dose (CLD) administration of cisplatin (CLD-BOMP) for patients with recurrent cervical carcinoma. PATIENTS AND METHODS: Ninety patients with recurrent cervical carcinoma and no prior chemotherapy were enrolled onto this study. The median age was 56 years. Eighty-seven of the 90 patients had received prior radiotherapy. The CLD-BOMP regimen was bleomycin 5 mg infused continuously days 1 through 7; vincristine 0.7 mg/m2 bolus day 7; mitomycin 7 mg/m2 bolus day 7; and cisplatin 10 mg/m2 infused over 4 hours days 1 through 7. The treatment was repeated at 3-week intervals. RESULTS: All 90 patients were assessable for response, toxicity, and survival. After a median of four cycles (range, two to 10 cycles), we observed objective responses in 68 patients (76%), with 25 (28%) complete responses (CRs) and 43 (48%) partial responses (PRs; 95% confidence interval (CI), 66 to 85; 18 to 38; 37 to 59, respectively). Median survival for all 90 patients was 24.3 months (range, 2.3 to 100 months). The median survival for patients who achieved CR, PR, no change (NC), and progressive disease (PD) were not reached (NR), 23.6, 8.2, and 6.4 months, respectively. The median progression-free survival for patients who achieved CR and PR were NR and 12.3 months, respectively. There was no significant nausea or vomiting, nephrotoxicity, or pulmonary toxicity, which was attributable to the CLD-cisplatin and the adequate dosing schedule of bleomycin. The reduced toxicities allowed this regimen to be administered at the projected dose-intensities. CONCLUSION: The CLD-BOMP regimen has significant antitumor activity with markedly reduced toxicity.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Uterine Cervical Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bleomycin/administration & dosage , Bleomycin/adverse effects , Cisplatin/administration & dosage , Cisplatin/adverse effects , Drug Administration Schedule , Female , Humans , Infusions, Intravenous , Middle Aged , Mitomycin/administration & dosage , Mitomycin/adverse effects , Multivariate Analysis , Survival Rate , Uterine Cervical Neoplasms/mortality , Vincristine/administration & dosage , Vincristine/adverse effects
11.
J Bone Miner Res ; 11(11): 1784-92, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8915787

ABSTRACT

To estimate the response to hormone replacement therapy (HRT) by bone metabolic markers, 36 patients with postmenopausal osteoporosis or osteopenia were studied to assess the correlation between percent baseline changes in lumbar bone mineral density (BMD) after 12 months and those in various bone metabolic markers after 3, 6, and 12 months of HRT. All the patients were treated with 0.625 mg of conjugated estrogen and 2.5 mg of medroxyprogesterone per day and continued for 12 months. BMD was significantly increased up to 4.19 +/- 0.87% after 6 months and 4.93 +/- 1.27% after 12 months of HRT (p = 0.0001 by analysis of variance). In accordance with this, changes in the levels of osteocalcin (p = 0.041), alkaline phosphatase (p = 0.0001), N-terminal osteocalcin (p = 0.0001), urinary excretion of pyridinoline/Cr (p = 0.0001), and deoxypyridinoline/Cr (p = 0.0001) were significantly decreased, respectively. Among these bone metabolic markers, only the change in the serum N-terminal osteocalcin at 3 months (r = 0.557, p = 0.0022), at 6 months (r = 0.470, p = 0.0184), and at 12 months (r = 0.545, p = 0.0061) significantly correlated with the change in BMD 12 months after HRT. The elution profiles of immunoreactive osteocalcin-related molecules in serum fractionated by reverse-phase high performance liquid chromatography revealed that the N-terminal fragment as well as the intact osteocalcin molecule decreased after 3 months of HRT. These results demonstrate that N-terminal osteocalcin is a suitable predictor for estimating good responders to HRT in postmenopausal women.


Subject(s)
Bone Density/drug effects , Bone and Bones/drug effects , Estrogen Replacement Therapy , Osteocalcin/blood , Postmenopause/blood , Analysis of Variance , Antibody Specificity , Biomarkers/blood , Bone and Bones/metabolism , Chromatography, High Pressure Liquid , Epitope Mapping , Female , Humans , Medroxyprogesterone/therapeutic use , Middle Aged , Prognosis
12.
FEBS Lett ; 318(1): 88-90, 1993 Feb 22.
Article in English | MEDLINE | ID: mdl-8436232

ABSTRACT

The antibiotic patulin was found to inhibit protein prenylation in mouse FM3A cells. Thus, the agent reduced incorporation of [3H]mevalonate into proteins by 50% at a concentration of 7 microM. In a cell-free assay, patulin inhibited rat brain farnesyl:protein transferase, one of the enzymes responsible for protein prenylation. The inhibition was 50% at a concentration of 290 microM.


Subject(s)
Alkyl and Aryl Transferases , Patulin/pharmacology , Protein Prenylation/drug effects , Animals , Brain/enzymology , Cells, Cultured , Cycloheximide/pharmacology , Leucine/metabolism , Mevalonic Acid/metabolism , Mice , Rats , Transferases/antagonists & inhibitors , Trichothecenes/pharmacology
13.
FEBS Lett ; 418(1-2): 58-62, 1997 Nov 24.
Article in English | MEDLINE | ID: mdl-9414095

ABSTRACT

Staplabin (0.3-0.6 mM), a fungal triprenyl phenol, enhanced 3-fold the plasminogen activator-catalyzed activation of Glu-plasminogen and Lys-plasminogen as well as their binding to fibrin. Staplabin was not stimulatory to the amidolytic activity of plasmin and plasminogen activators. Even in the presence of epsilon-aminocaproic acid (EACA) and fibrinogen fragments, allosteric effectors for Glu-plasminogen, staplabin increased the activation of both forms of plasminogen. In size-exclusion chromatography of Glu-plasminogen and Lys-plasminogen, the molecular elution time, which varies as the conformation of a protein changes, was shortened by staplabin. These results suggest that staplabin causes plasminogens to be more susceptible to activation and fibrin binding by inducing a conformational change that is, at least in part, different from that induced by EACA and fibrinogen fragments.


Subject(s)
Benzopyrans/pharmacology , Fibrin/metabolism , Fibrinolysin/metabolism , Peptide Fragments/metabolism , Plasminogen Activators/pharmacology , Plasminogen/metabolism , Protein Conformation/drug effects , Pyrrolidinones/pharmacology , Allosteric Regulation , Aminocaproic Acid/pharmacology , Enzyme Activation , Fibrinogen/metabolism , Humans , Kinetics , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Plasminogen/chemistry , Plasminogen/drug effects , Thrombin/metabolism
14.
Bone ; 20(6): 557-62, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9177871

ABSTRACT

50 Japanese women within 10 years after menopause (mean age 52.5 years) were studied to determine the effects of 0.75 microgram of 1-alpha-hydroxyvitamin D3 [1-alpha-(OH)D3] with calcium (150 mg/day) (treated group: N = 25) and calcium only (control group: N = 25) for 12 months on bone mass and metabolism. Their L2-4 BMD measurements were 1.5 SD below the mean value of Japanese young, normal women. L2-4 BMDs increased significantly in the treated group (+2.1%; p < 0.01), but decreased significantly in controls (-2.1%; p < 0.01). Although serum calcium and creatinine remained unchanged in both groups, phosphorus levels increased significantly in the treated group (p < 0.01). Urinary calcium/creatinine (Cr) increased in both groups. Urinary pyridinoline/Cr and deoxypyridinoline/Cr decreased significantly in the treated group (p < 0.05), but not in the control group. Serum osteocalcin levels remained unchanged in both groups. Intact parathyroid hormone levels decreased significantly (p < 0.05) and calcitonin levels significantly increased in the treated group (p < 0.05), but these changes were not observed in the control group. These data clearly demonstrate that 0.75 microgram of 1-alpha-(OH)D3 maintained bone mass by reducing bone resorption by modulation of calcium-regulating hormones. Temporarily increased urinary calcium excretion was observed in control group, but did not appear to be effective in modulating bone turnover.


Subject(s)
Bone and Bones/metabolism , Calcitonin/drug effects , Hydroxycholecalciferols/therapeutic use , Osteoporosis/drug therapy , Parathyroid Hormone/blood , Postmenopause , Biomarkers/blood , Biomarkers/urine , Bone Density/drug effects , Bone and Bones/drug effects , Calcitonin/blood , Female , Humans , Lumbar Vertebrae/chemistry , Middle Aged
15.
Thromb Haemost ; 77(1): 137-42, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9031464

ABSTRACT

Plasminogen binds to endothelial and blood cells as well as to fibrin, where the zymogen is efficiently activated and protected from inhibition by alpha 2-antiplasmin. In the present study we have found that complestatin, a peptide-like metabolite of a streptomyces, enhances binding of plasminogen to cells and fibrin. Complestatin, at concentrations ranging from 1 to 5 microM, doubled 125I-plasminogen binding to U937 cells both in the absence and presence of lipoprotein(a), a putative physiological competitor of plasminogen. The binding of 125I-plasminogen in the presence of complestatin was abolished by epsilon-aminocaproic acid, suggesting that the lysine binding site(s) of the plasminogen molecule are involved in the binding. Equilibrium binding analyses indicated that complestatin increased the maximum binding of 125I-plasminogen to U937 cells without affecting the binding affinity. Complestatin was also effective in increasing 125I-plasminogen binding to fibrin, causing 2-fold elevation of the binding at approximately 1 microM. Along with the potentiation of plasminogen binding, complestatin enhanced plasmin formation, and thereby increased fibrinolysis. These results would provide a biochemical basis for a pharmacological stimulation of endogenous fibrinolysis through a promotion of plasminogen binding to cells and fibrin.


Subject(s)
Chlorophenols/pharmacology , Complement Inactivator Proteins/pharmacology , Fibrin/metabolism , Monocytes/metabolism , Oligopeptides/pharmacology , Peptides, Cyclic , Plasminogen/metabolism , Cell Line , Humans , Protein Binding/drug effects
16.
Thromb Haemost ; 79(3): 591-6, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9531047

ABSTRACT

Plactin D, a cyclic pentapeptide [cyclo(-D-Val-L-Leu-D-Leu-L-Phe-D-Arg-)] produced by a fungal strain, enhances fibrinolytic activity (6). The present study deals with the structure-activity relationship of plactins and their effects in U937 cells and mice. The results obtained from 50 plactin D analogues with a single amino acid substitution demonstrated that the following substitutions were detrimental: the enantiomer for each of the five residues; a polar, an acidic or a basic residue for D-Val, L-Leu, D-Leu or L-Phe; a polar, a hydrophobic or an acidic residue for D-Arg. On the other hand, a compound with L-Leu or L-Val in place of L-Phe was seven times as active as plactin D. These results suggest an essential role of a sterically restricted arrangement of four hydrophobic residues and the adjacent basic residue. The enhancement of fibrinolysis was dependent on plasma, ranging from 2- to 3-fold when U937 cells were incubated with 15-30 microM plactin D in the presence of 6-50% plasma, while no elevation was observed when cells were incubated in the absence of plasma. Plasminogen alone could not substitute for plasma. The plactin D effect was totally abolished by anti-urokinase IgG but not by anti-tissue plasminogen activator IgG. Plactin D caused a plasma-dependent, transient increase in the cellular urokinase activity. This urokinase activation may have accounted for the increased fibrinolytic activity of plactin D-treated U937 cells. Homogenates of the lung obtained from mice 0.5 to 2 h after intravenous plactin D (5 mg/kg) showed 2- to 3-fold increased levels of fibrinolytic activity, while activities of the brain, heart, liver, spleen, kidney and aorta were not significantly affected. In conclusion, plactin D enhances fibrinolysis both in cultured mammalian cells and in experimental animals.


Subject(s)
Fibrinolysis/drug effects , Fibrinolytic Agents/pharmacology , Monocytes/metabolism , Peptides, Cyclic/pharmacology , Animals , Cell Line , Fibrinolytic Agents/chemistry , Humans , Mice , Peptides, Cyclic/chemistry , Structure-Activity Relationship
17.
Int J Oncol ; 2(2): 179-84, 1993 Feb.
Article in English | MEDLINE | ID: mdl-21573533

ABSTRACT

Thirty-six patients with advanced or recurrent endometrial cancer having had no previous chemotherapy were treated with cisplatin-based chemotherapy. The overall response rate was 38.9%. The mean time to response and the mean duration of response were 9.6 weeks and 16.9 months, respectively. There was no significant difference in response and survival probability between persistent disease and recurrent disease. Size of tumor had a marked influence on response, while age, history of previous irradiation and histologic grade of adenocarcinoma did not affect the response rate. Survival probability by response clearly demonstrated that only complete response exhibited a large impact on survival.

18.
Int J Oncol ; 5(4): 827-31, 1994 Oct.
Article in English | MEDLINE | ID: mdl-21559648

ABSTRACT

The effects of human recombinant granulocyte colony-stimulating factor (rhG-CSF) on leukocyte kinetics and immune function were assessed in patients with gynecologic malignancies receiving cytotoxic chemotherapy. Five day-rhG-CSF administration (50 mu g/m(2)/day) increased leukocyte counts in most of the chemotherapy courses. There was a significant difference in the leukocyte increase between the previously irradiated group and the nonirradiated group. An appreciable increase in LAK activity owing to an increased IL-2 production was noted after rhG-CSF administration. Despite a remarkable increase in the neutrophils observed, the CD57(+) cell count and NK activity in peripheral blood mononuclear cells were unexpectedly reduced.

19.
Aliment Pharmacol Ther ; 14 Suppl 1: 188-92, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10807423

ABSTRACT

BACKGROUND: Helicobacter pylori has been implicated in the pathogenesis of gastric cancer and malignant lymphoma. It is not known whether the bacterium stimulates cell proliferation directly or if apoptosis induced by H. pylori leads to a hyperproliferative response. AIM: To clarify the precise mechanism of H. pylori action on gastric epithelial cell growth, we compared the response of two cell lines, Kato III (p53 deletion) and MKN 45 (p53 wild type), to the organism. To determine the role of Helicobacter vacuolating cytotoxin in gastric mucosal injury, we examined the relation between vacuolating activity and apoptosis under several conditions. METHODS: Five cytotoxic and four noncytotoxic strains of H. pylori were used, each with an inoculum of 10(7) cfu/mL. The effect on the growth in MKN 45 and Kato III cells was studied by MTT assay. Vacuolating cytotoxin activity was determined using RK-13 cells. RESULTS: Neither cytotoxic nor noncytotoxic strains induced apoptosis, but death of MKN 45 cells was induced by pre-treatment with interferon-gamma and culture with TNF-alpha. In contrast, some strains of H. pylori increased proliferation of Kato III cells. Furthermore, cell death induced by cytotoxic strains, but not noncytotoxic strains, was significantly augmented by amoxycillin 5-50 g/mL (P=0.0016). On the other hand, acid-treated supernatant fluids from cultures of H. pylori showed enhanced vacuolating activity but did not induce cell death, suggesting that death is attributable to some factor other than the cytotoxin. CONCLUSION: These findings suggest that H. pylori induces apoptosis by a means independent of vacuolating cytotoxin.


Subject(s)
Apoptosis , Epithelial Cells/cytology , Gastric Mucosa/cytology , Helicobacter pylori , Cell Division , Cell Line , Cytoprotection , Gastric Mucosa/microbiology , Helicobacter Infections/complications , Humans , Interferon-gamma/pharmacology , Stomach Neoplasms/etiology , Tumor Necrosis Factor-alpha/pharmacology
20.
Aliment Pharmacol Ther ; 16 Suppl 2: 235-9, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11966547

ABSTRACT

BACKGROUND: Helicobacter pylori and nonsteroidal anti-inflammatory drugs (NSAIDs) are important factors in gastric mucosal injury. However, the relationship between H. pylori and NSAID-related gastroduodenal mucosal injury has not been clarified. AIM: To determine the role of H. pylori in NSAID-induced gastric mucosal injury and to examine the effects of H. pylori, indomethacin and sofalcone on gastric epithelial cells in culture, as a useful model to study gastric mucosal injury. In addition, we studied the effect of sofalcone, a gastric mucosal protection agent, on H. pylori and NSAID-induced gastric mucosal injury. METHODS: Cytotoxic and noncytotoxic strains of H. pylori were used, each with an inoculum of 10(7) cfu/mL. The effect on the growth of RGM-1 cells (a rat gastric epithelial cell line) was studied by MTT assay, and levels of prostaglandin E2 in culture supernatants were measured by EIA. RESULTS: Both cytotoxic and noncytotoxic strains of H. pylori tended to induce cell injury in RGM-1 cells at 48 h after inoculation. Indomethacin alone induced gastric epithelial injury in a dose-dependent manner, but did not augment cell injury induced by H. pylori. In addition, sofalcone (10(-5) mol/L) showed a suppressive effect on indomethacin-induced gastric epithelial injury. CONCLUSION: These findings indicate that indomethacin induces gastric mucosal injury regardless of H. pylori infection, and suggests that sofalcone may be a useful drug in the treatment of NSAID-induced mucosal injury.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/toxicity , Gastric Mucosa/pathology , Helicobacter Infections/physiopathology , Helicobacter pylori/isolation & purification , Indomethacin/toxicity , Animals , Cell Line , Cell Survival/drug effects , Cell Survival/physiology , Epithelial Cells/drug effects , Epithelial Cells/pathology , Gastric Mucosa/drug effects , Helicobacter Infections/microbiology , Rats
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