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J J Barlow

Publications and source records attributed to J J Barlow.

At least 19 recordsLinked to original sources

Studies leading to the identification of ZD1839 (IRESSA): an orally active, selective epidermal growth factor receptor tyrosine kinase inhibitor targeted to the treatment of cancer.

This paper describes the development of the epidermal growth factor receptor tyrosine kinase inhibitor ZD1839 from a lead series of 4-anilinoquinazoline compounds. ZD1839 has suitable properties for use as a clinically effective drug and shows activity against human tumours. In particular, the use of pharmacokinetic data in the development of ZD1839 is discussed.

Administration, Oral↗

Structure/activity studies related to 2-(3,4-dichlorophenyl)-N-methyl-N-[2-(1-pyrrolidinyl)-1-substituted- ethyl]acetamides: a novel series of potent and selective kappa-opioid agonists.

This paper describes the synthesis of a series of N-[2-(1-pyrrolidinyl)ethyl]acetamides 1, variously substituted at the carbon adjacent to the amide nitrogen (C1), and related analogues, together with their biological evaluation as opioid kappa agonists. In the first part of the study, the variants in N-acyl, N-alkyl, and amino functions were explored when the substituent at C1 was 1-methylethyl and the optimum was found to be exemplified by 2-(3,4-dichlorophenyl)-N-methyl-N-[(1S)-1-(1-methylethyl)-2- (1-pyrrolidinyl)ethyl]acetamide (13). Subsequently, racemic or chiral amino acids were used to introduce other alkyl and aryl substituents at C1 of the ethyl linking moiety. A series of potent compounds, bearing substituted-aryl groups at C1, were discovered, typified by 2-(3,4-dichloro-phenyl)-N-methyl-N-[(1R,S)-1-(3-aminophenyl)-2-(1- pyrrolidinyl)ethyl]acetamide (48), which was 5-fold more active as the racemate than 13 in vitro and exhibited potent naloxone-reversible analgesic effects (ED50 = 0.04 mg/kg sc) in a mouse abdominal constriction model.

Acetamides↗

A novel series of potent and selective agonists at the opioid kappa-receptor.

Three novel opioid agonists are described. These compounds were found to bind with high affinity and selectivity to the kappa-opioid receptor. Isolated tissue studies using the field-stimulated mouse vas deferens and guinea-pig ileum preparations confirmed the high agonist potency and naloxone-reversibility of these agents. All three compounds exhibited potent antinociceptive activity in the mouse abdominal constriction model. These compounds should prove useful as tools to investigate kappa-receptor function.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

Expression of a high molecular weight mucin-type glycoprotein in human colon cancer as defined by monoclonal antibody 1D3.

Murine monoclonal antibody 1D3 recognizes a high molecular weight acidic mucin restricted to the epithelium of normal colonic mucosa and goblet cells. Of 72 colonic carcinoma specimens examined, 29 were found to have detectable level of 1D3 antigen by an indirect immunoperoxidase staining assay on fixed, paraffin-embedded tissue sections. In some specimens a focal staining pattern was observed, while in others 50-90% of tumor cells were stained. Of 28 cases having adjacent normal mucosa, all 28 showed intense staining reaction in the normal mucosa and goblet cells despite the fact that 18 of the tumors were unstained. One of 1 colonic diverticulosis, 2 of 2 ulcerative colitis, 3 of 3 villo-glandular polyps, 19 of 20 adenomatous polyps and 17 of 19 hyperplastic polyps were also stained heavily for the 1D3 antigen. Colonic carcinomas displayed a range of staining patterns and a great degree of antigenic heterogeneity. Well-differentiated tumors characterized by typical goblet cells were almost always positive (10 of 12). As cellular structure became disorganized, as in moderately-differentiated tumors, about 33% of the tumors (17 of 51) stained for 1D3 antigen. As the tumor became more invasive with further disorientation of cellular features, as in poorly differentiated tumors, very few specimens (2 of 9) were positive. It was apparent that with the progression of de-differentiation there was a gradual loss of 1D3 antigen in human colonic tumors.

Antibodies, Monoclonal↗

Characterization of the antigen recognized by monoclonal antibody 1D3.

Human ovarian mucinous cystadenocarcinoma-associated antigen recognized by murine monoclonal antibody 1D3 (Bhattacharya et al., 1982) was characterized. Gel filtration and sodium dodecylsulfate polyacrylamide gel electrophoresis, followed by Western-blot analysis showed that 1D3 is a high molecular weight glycoprotein. Isoelectric focusing of 1D3 antigen showed 2 overlapping antigenic components with PI 2.5 and 2.6. 1D3 antigen was extremely stable (10 min at 100 degrees C) to heating. The antigenic activity was slightly stimulated by treatment with galactosidases, but neuraminidase treatment enhanced the antigenic activity about 3-fold. Antigen activity was completely stable to periodate oxidation. Pronase and trypsin treatment completely destroyed the antigenic activity. Properties of 1D3 antigen suggest that this is a high molecular weight (approximately 5-20 x 10(6) Dalton), sialomucin. Monoclonal antibody 1D3 recognizes only the protein part of this molecule.

Animals↗

ICI 147,798: a novel diuretic agent with beta adrenoceptor blocking activity.

ICI 147,798 is a novel compound which has both diuretic and beta adrenoceptor blocking properties in a single molecule. The natriuretic activity at 30 mg/kg p.o. was about 65% of the hydrochlorothiazide value at 10 mg/kg p.o. in saline-loaded rats; the corresponding kaliuretic activity was 42%. The natriuretic and the kaliuretic activity of ICI 147,798 in dogs were similar to that of hydrochlorothiazide over the doses 1 to 20 mg/kg p.o., although significantly less kaliuresis was obtained with ICI 147,798 at 1 mg/kg p.o. In the toad bladder preparation (analogous to the distal mammalian nephron), ICI 147,798 inhibited Na+ transport with mucosal and serosal IC50 values of 56 and 120 microM, respectively. ICI 147,798 inhibited isoproterenol-induced tachycardia in rats, cats, guinea pigs and dogs; these effects were associated with antagonism of isoproterenol vasodepressor responses. The pKB values of ICI 147,798 were 9.1 and 8.8 in isolated right atria and trachea of guinea pigs, respectively. ICI 147,798 did not exhibit local anesthetic activity in rabbit cornea and intrinsic sympathomimetic activity in catecholamine-depleted dogs and rats. Duration of beta blockade after a p.o. dose of 1 mg/kg in dogs followed the sequence: nadolol greater than ICI 147,798 greater than atenolol greater than timolol greater than propranolol. It is concluded that ICI 147,798 is a novel diuretic agent with nonselective beta blockade, and it appears to have the potential of a direct tubular action.

Adrenergic beta-Agonists↗

N-acetyl-beta-D-glucosaminyltransferases related to the synthesis of mucin-type glycoproteins in human ovarian tissue.

The presence of N-acetyl-beta-D-glucosaminyltransferases in microsome preparations from human ovarian tissues was investigated with UDP-GlcNAc and several synthetic oligosaccharides as acceptors. The products were identified by paper chromatography and the linkage of the 2-acetamido-2-deoxy-beta-D-glucopyranosyl group incorporated into oligosaccharides was determined by exoglycosidase digestions, 1H-n.m.r. spectroscopy, and methylation analysis. These results showed that ovarian microsome preparations contain both beta-(1----3)- and beta-(1----6)-N-acetyl-D-glucosaminyltransferase activities which might be involved in the synthesis of mucin-type glycoproteins. Substrate competition tests suggested that both UDP-GlcNAc:-Bn glycoside of beta-D-GlcpNAc-(1----6)-alpha-D-GalpNAc [GlcNAc to GalNAc] and -Bn glycoside of beta-D-Galp-(1----3)-[beta-D-GlcNAc-(1----6)]-alpha-D-GalpNAc [GlcNAc to Gal] beta-(1----3)-N-acetyl-D-glucosaminyltransferase activities reside in a single enzyme species.

Carbohydrate Conformation↗

Etoposide (VP-16) plus cisplatin (DDP): a new active chemotherapeutic combination in patients with stage III-IV ovarian adenocarcinoma.

Ten patients with Stage III-IV ovarian adenocarcinoma were treated with the drug combination etoposide (VP-16) plus cisplatin (DDP). All patients were in relapse following prior vigorous, uninterrupted treatment with three or more lines of chemotherapy that included (1) courses of weekly 1-mg/kg single-agent DDP, (2) DDP 50 mg/m2 in various combinations with or without cytoxan, adriamycin and hexamethylmelamine q 4 weeks and (3) high-dose methotrexate-leucovorin plus cyclophosphamide (MECY) q 4 weeks. The median duration of treatment prior to starting VP-16-DDP was 27.5 months (range 6 to 53 months). VP-16-DDP was given as a 2-day regimen repeated every 4 weeks. VP-16, 100-150 mg/m2, was given on days 1 and 2, and 50 mg/m2 of DDP on day 1 only. The finding of 50% partial response and 38% stabilization of measurable tumor was remarkable in patients so extensively pretreated. The responses were not due to increased DDP dosage, but rather to an apparent synergism between VP-16 and DDP.

Aged↗

Specific activity of alpha-L-fucosidase in sera with phenotypes of either low, intermediate, or high total enzyme activity and in a fucosidosis serum.

The quantity of alpha-L-fucosidase activity in human serum is determined by heredity. An individual may inherit either low, intermediate, or high serum enzyme activity. An enzyme-linked immunoabsorbent assay has been developed that can detect 0.3 ng of alpha-L-fucosidase protein. Enzyme protein in serum of 102 individuals ranged from 20 to 835 ng/ml. The group included individuals with low, intermediate, and high enzyme activity. The specific activity of alpha-L-fucosidase within this group was statistically the same (mean +/- SD = 11,002 +/- 1051 U/mg). Thus, individuals with low and intermediate enzyme activity in serum had lower amounts of enzyme protein with the same specific activity as in individuals with high enzyme activity. Fucosidosis is a rare inherited disease in which alpha-L-fucosidase activity in tissues and body fluids is low or absent. The concentrations of enzyme protein in sera of a fucosidosis patient and parents were 76,565, and 604 ng/ml, respectively, and the specific activities of enzyme were 1316, 8938, and 8858 U/mg, respectively. Thus, the fucosidosis serum probably contained a structurally altered enzyme with reduced catalytic activity. The somewhat low specific activities in the parents suggested that their sera contained both structurally altered and normal protein.

Alleles↗

Use of N-acetyl-2'-O-methyllactosamine as a specific acceptor for the determination of alpha-L-(1----3)-fucosyltransferase in human serum.

A synthetic substrate, N-acetyl-2'-O-methyllactosamine, was employed as a specific acceptor for alpha-L-(1----3)-fucosyltransferase from human serum. The fucosyl linkage of the product from this substrate was characterized by hydrolysis with a specific alpha-L-(1----3)/(1----4)-fucosidase. Using this acceptor, the pH optimum for the serum alpha-L-(1----3)-fucosyltransferase was 6.5. The enzyme was activated by Mn2+ or Mg2+ ions and was inhibited by EDTA. The apparent Km for this enzyme using N-acetyl-2'-O-methyllactosamine was 20.4 mM and Vmax was 5.6 pmol/h/ml serum.

Amino Sugars↗

Elevated serum alpha(1----3)-L-fucosyltransferase activity with synthetic low molecular weight acceptor in human ovarian cancer.

Serum alpha(1----3)-L-fucosyltransferase activity was measured in 29 ovarian cancer patients with active disease, 26 ovarian cancer patients with no clinical evidence of disease and 23 healthy females. N-Acetyl-2'-O-methyl-lactosamine was used as the acceptor for the enzyme. The level of the enzyme activity was significantly (P less than 0.05) higher in the serum of patients with known tumor when compared to healthy controls and patients with no clinical evidence of disease.

Amino Sugars↗

Characterization of products synthesized by galactosyltransferase purified from the ascites of ovarian cancer patients.

Galactosyltransferase purified from the ascites of ovarian cancer patients can use to an equal extent N-glycosidic glycoproteins, such as asialoagalactofetuin, and O-glycosidic mucin, such as asialo bovine submaxillary mucin (BSM), as acceptors. Thermal treatment and substrate competition experiments demonstrated that the same enzyme catalyzed the transfer of galactose to both types of acceptors. Alkaline borohydride treatment showed that, while the product with asialoagalactofetuin was totally resistant, about 90% of the product with asialo BSM was hydrolyzed by this treatment. Gel filtration of the released oligosaccharides on a calibrated Biogel P-2 column showed three peaks. One major oligosaccharide (O-2) of size 5.7 glucose U and two minor peaks (O-1 and O-3) of sizes 8.7 and 3.7 glucose U, respectively, were obtained. The oligosaccharides were doubly labeled, first by incubation with uridine-diphosphate [14C]galactose, followed by alkali treatment in the presence of [3H]borohydride. The doubly labeled oligosaccharides were separately purified by gel filtration and ion-exchange chromatography and digested with various exoglycosidases. The digested products were characterized by gel filtration and paper chromatography in three different systems. From these results, the structures of these oligosaccharides were computed as follows: O-1 = beta-galactosyl-beta-N-acetylglucosamine-galactosaminitol (sialic acid); O-2 = beta-galactose-beta-N-acetylglucosamine-galactosaminitol; O-3 = beta-galactose-galactosaminitol. These results suggest that the galactosyltransferase from the ascites of ovarian cancer patients catalyzes the transfer of galactose to N-acetylglucosamine, irrespective of whether it is a part of an N-glycan or an O-glycan.

Acetylglucosamine↗

Long-term survival rates with various chemotherapeutic regimens in stages III and IV ovarian adenocarcinoma. The influence of optimum pretreatment surgical resection.

This report compares long-term survival rates for patients treated with four different chemotherapeutic regimens for Stages III and IV ovarian adenocarcinoma. The patients were entered into consecutive, prospective, randomized studies with an essentially common chemotherapeutic arm. The first study compared the single agent melphalan with actinomycin D, 5-fluorouracil, and Cytoxan. The second study compared 5-fluorouracil plus Cytoxan and methotrexate-leucovorin rescue plus Cytoxan. The patient characteristics in the two studies were very similar except for more aggressive tumor-reductive operations in the second study. Observed survival rates for the first 2 years in the second study were very much higher than in the first study. However, by the third, fourth, and fifth years, the survival rates of the 5-fluorouracil-Cytoxan-treated individuals had reached the same low levels seen in the first study. It appears that an optimum surgical procedure by itself may enhance survival during the first 2 years. Survival with methotrexate-leucovorin rescue plus Cytoxan was statistically significantly better than with melphalan or actinomycin D-5-fluorouracil-Cytoxan. Third-, fourth-, and fifth-year survival rates with methotrexate-leucovorin rescue plus Cytoxan were substantially higher than with 5-fluorouracil-Cytoxan; however, the survival distributions for these two treatments were not statistically significantly different. Long-term survival rate data for patients with Stages III and IV ovarian adenocarcinomas treated with chemotherapy are rare. The 19% 5-year survival rate with methotrexate-leucovorin rescue plus Cytoxan in the present study is considerably higher than other reported survival rates.

Adenocarcinoma↗

Production of murine monoclonal antibodies against cell-surface antigens of human ovarian carcinoma.

Splenic lymphocytes of BALB/c mice immunized with human ovarian carcinoma cells were fused with the mouse myeloma cell line, NS-1 in the presence of polyethylene glycol, MW 1500. The hybrid cultures were screened by a viable cell-binding radioimmunoassay (RIA) for the production of relevant antibodies. Hybrids that produced antibodies that bound to the surface of the immunizing cell line and other ovarian carcinoma cell lines, but not to human fibroblast cell lines or erythrocytes and leucocytes isolated from peripheral blood, were cloned twice by the limiting dilution method. Two such clones designated 8C3, of the IgG2a isotype, and 10D6, of the IgG1 isotype, were checked for specificity by a solid-phase membrane RIA. The monoclonal antibodies (MoAbs) recognized an antigenic determinant present on different human adenocarcinomas such as ovary, breast, endometrium, colon, and stomach. The normal counterpart tissues of these histiotypes showed negligible binding to the MoAbs. The relative specificity of these MoAbs encourage further studies towards their characterization and evaluation as possible diagnostic and therapeutic agents in human cancer.

Adenocarcinoma↗

Production and characterization of monoclonal antibody to a 60-kD glycoprotein in ovarian carcinoma.

Monoclonal IgG1 antibodies 2C8 and 2F7, derived by immunization of mice with a glycoprotein-enriched fraction of human ovarian adenocarcinoma, recognized a 60 kD glycoprotein in the ovarian tumor but not in normal ovary. Survey of other normal adult tissues by an indirect solid-phase radioimmunoassay (RIA) revealed the presence of the antigen in trace amounts in various normal organs such as small intestine, liver colon and urinary bladder, except in lung where its concentration was as high as in tumors. Among fetal tissues tested, intestine and placenta had the highest activities. By RIA, about 50% of ovarian and colonic tumors had elevated levels of the antigen. All ovarian cyst fluids, both benign as well as malignant, also contained a high level of the antigen. Immunodepletion studies indicated that the antigen was distinct from carcinoembryonic antigen and the ovarian cancer antigens described in our laboratory with other monoclonal antibodies. The antigen bound to Con A-Sepharose and was eluted with 2% alpha-D-mannoside, was soluble in 0.6 M perchloric acid and stable at 100 degrees C for 30 min. The antigenic activity in isolated plasma membrane enriched fractions of ovarian adenocarcinomas was sensitive to trypsin, chymotrypsin or protease treatment but unaffected by neuraminidase, beta-galactosidase, periodate or methanol treatment. By immunoperoxidase staining, the antigen was localized in a variety of human tumors showing widespread distribution.

Adenocarcinoma↗

Immunoperoxidase localization of a high-molecular-weight mucin recognized by monoclonal antibody 1D3.

The distribution of an antigen recognized by murine monoclonal antibody 1D3 (Bhattacharya, M., Chatterjee, S.K., Barlow, J. J., and Fuji, H. Cancer Res., 42: 1650-1654, 1982) was investigated in various types of human malignant and normal adult tissues by indirect immunoperoxidase assay in fixed paraffin-embedded sections. One hundred percent of ovarian mucinous cystadenocarcinomas expressed high levels of the antigen with intense staining of 80 to 100% of the tumoral area, thus confirming our previous finding with radioimmunoassay and absorption analyses. About 51% of colonic carcinomas, 33% of gastric carcinomas, and 22% of pancreatic carcinomas were also positive for this high-molecular-weight mucoprotein antigen. All other ovarian and nonovarian carcinomas tested including carcinoma of lung, breast, endometrium, cervix, and prostate were not stained by 1D3. In addition, sarcomas, melanomas, and lymphomas also did not express any detectable level of the antigen. When surveyed against various normal adult tissues, 1D3 had reactivity limited to the colon. Normal colon, however, exhibited reduced staining intensities compared to tumors or to the apparently normal colon adjacent to tumors. The antigen thus appears to be a colorectal tissue-specific antigen showing increased levels in ovarian mucinous cystadenocarcinomas and in some gastrointestinal tumors. 1D3 antigen is a potential tumor marker for mucinous ovarian and colonic tumors.

Animals↗

Biochemical and immunologic characterization of galactosyltransferase purified from the ascites of ovarian cancer patients.

Galactosyltransferase appears to be a promising marker for ovarian carcinoma. For an understanding of its role in this cancer, the enzyme was purified from the ascites of ovarian cancer patients, and its biochemical and immunologic properties were studied. For adequate recovery and stability, Triton X-100 (0.01%) was necessary in all the buffers used for the purification of this enzyme. Immunoglobulins were not detectable in this preparation, which showed a single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Electrophoresis under nondenaturing conditions resolved the enzyme into two to three active components. An antiserum in rabbits, however, produced a single precipitin line suggesting a single determinant. By chromatography in concanavalin A-Sepharose 4B, the enzyme can be resolved into two components (F-1 and F-2). Purified galactosyltransferase and components F-1 and F-2 all catalyzed the transfer of galactose from UDP-galactose to alkali-stable beta-N-glycosidic acceptors, as well as to alkali-labile beta-O-glycosidic mucin-type acceptors. In addition, they catalyzed the N-acetyllactosamine synthetase reaction and, in the presence of alpha-lactalbumin, the lactose synthetase reaction. Galactosyltransferase and components F-1 and F-2 differed in their sensitivity to alpha-lactalbumin-induced inhibition of N-acetyllactosamine synthesis. Galactosyltransferase in the malignant ascites exists as different isoforms, which do not differ significantly in major biochemical and immunologic properties.

Amino Sugars↗

Purification of a beta-D-galactosidase from bovine liver by affinity chromatography.

A beta-D-galactosidase from bovine liver was purified to apparent homogeneity. The major purification step was affinity chromatography on a column of D-galactose attached to a Sepharose support activated with divinyl sulfone. Affinity media prepared by binding ligands to Sepharose activated with cyanogen bromide were unsuitable for purification of the enzyme, even though such media have been used to purify beta-D-galactosidases from other sources. The molecular weight of the denatured enzyme was 67,000. The molecular weight of the native enzyme at pH 7.0 was 68,000, and at pH 4.5 or 5.0, was 141,000. These data suggest that the enzyme has a single, fundamental subunit with a molecular weight of 67,000, and that the enzyme exists as a monomer at pH 7.0, and a dimer at pH 4.5 or 5.0. The Vmax values of the enzyme with p-nitrophenyl beta-D-galactoside, p-nitrophenyl beta-D-fucoside, lactose, and beta-Gal-(1----4)-beta-GlcNAc-1---- OC6H4NO2 -p were 10,204, 11,550, 9,479, and 8,859 nmol/min/mg of protein, respectively, and the Km values for these substrates were 0.08, 14.9, 14.2, and 1.6mM, respectively. D-Galactose, beta-D- galactosylamine , p-aminophenyl 1-thio-beta-D-galactoside, and D- galactono -1,4-lactone were competitive inhibitors of the enzyme, with Ki values of 0.9, 0.6, 0.6, and 0.8mM, respectively. The enzyme catalyzed the transfer of the D-galactosyl group from p-nitrophenyl beta-D-galactoside to D-glucose. The pH optimum of the enzyme was 4.5, and the pI was 4.7.

Animals↗