Detection of hepatic micrometastasis in pancreatic adenocarcinoma patients by two-stage polymerase chain reaction/restriction fragment length polymorphism analysis

Hepatic metastasis and retroperitoneal recurrence generally are considered to be the two primary modes of recurrence in pancreatic cancer. The goal of this study was to determine if patients with pancreatic adenocarcinoma have hepatic and peritoneal micrometastasis at operation. Pancreatic adenocarcinomas are known to have a high incidence of K-ras gene mutations. Liver tissue specimens were obtained from 30 patients (17 with pancreatic adenocarcinoma and 13 with other diseases) with a biopsy needle at operation. Peritoneal washings were obtained during operation from 20 patients with pancreatic adenocarcinoma. Two-stage polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis were used to detect K-ras oncogene mutation at codon 12. Thirteen of 17 pancreatic adenocarcinoma patients had K-ras gene mutations in the liver, whereas all 13 patients with other diseases did not. However, only two of 20 pancreatic adenocarcinoma patients revealed K-ras gene mutation in peritoneal lavage fluids. These results indicate the feasibility of detecting hepatic micrometastasis in patients with pancreatic adenocarcinoma, and imply that PCR/RFLP analysis may be of value in the diagnosis, treatment and follow-up of hepatic metastasis of pancreatic adenocarcinoma.

[Study on the mechanisms of diarrhea induced by a new anticancer camptothecin derivative, irinotecan hydrochloride (CPT-11), in rats]

We investigated the mechanisms of CPT-11-induced diarrhea. 1) CPT-11 (80 mg/kg, i.v.) induced watery diarrhea within 1 hr after dosing in saline-loaded (10 ml/kg, p.o.) rats. This was partially inhibited by subcutaneous injection of atropine (1 mg/kg) or ondansetron (1 mg/kg) and almost completely inhibited by a combination of atropine and ondansetron or by clonidine (0.3 mg/kg) or morphine (10 mg/kg) alone. 2) CPT-11 at the same dose reduced intestinal fluid absorption, which was blocked by the anti-diarrheal agents mentioned above. Intraluminal injection of CPT-11 (20 mg/2 ml) inhibited fluid absorption and induced fluid secretion. 3) CPT-11, 60 mg/kg, by single intravenous injection induced fewer enzymological and histological changes in the small intestine than 5-FU at 270 mg/kg, while 4 consecutive dosings of CPT-11 induced delayed diarrhea (days 5-7) associated with disruption of intestinal integrity. Co-administration with anti-diarrheal agents, except for ondansetron, protected against watery diarrhea appearing within 1 hr after CPT-11 on days 3 and 4, but worsened delayed diarrhea. These results suggest that single injection of higher doses of CPT-11 causes watery diarrhea at an acute phase at least partly by reducing fluid absorption or increasing secretion, and that while conventional anti-diarrheal agents protect against watery diarrhea, their co-administration in repeated CPT-11 administration has no ameliorative effect on CPT-11-induced delayed diarrhea.

Control of CNS midline transcription by asymmetric E-box-like elements: similarity to xenobiotic responsive regulation

Central nervous system midline cells constitute a discrete group of Drosophila embryonic cells with numerous functional and developmental roles. Corresponding to their separate identity, the midline cells display patterns of gene expression distinct from the lateral central nervous system. A conserved 5 base pair sequence (ACGTG) was identified in central nervous system midline transcriptional enhancers of three genes. Germ-line transformation experiments indicate that this motif forms the core of an element required for central nervous system midline transcription. The central nervous system midline element is related to the mammalian xenobiotic response element, which regulates transcription of genes that metabolize aromatic hydrocarbons. These data suggest a model whereby related basic-helix-loop-helix-PAS proteins interact with asymmetric E-box-like target sequences to control these disparate processes.

Effects of cyclopiazonic acid on rhythmic contractions in uterine smooth muscle bundles of the rat

1. We studied the effects of cyclopiazonic acid (CPA) on rhythmic contractions and on Ca2+ uptake by the intracellular stores in longitudinal muscle strips of the rat uterus at 30 degrees C. 2. Oxytocin (1 microM) in Ca(2+)-free solution induced a transient rise in the intracellular Ca2+ concentration ([Ca2+]i) and contraction after Ca2+ loading of the stores in high-K(+)- and Ca(2+)-containing solution. CPA inhibited oxytocin-induced Ca2+ release and contraction, the half and full inhibitory concentrations of CPA being 0.3 and 10 microM, respectively. In contrast, addition of CPA after Ca2+ loading exerted no significant inhibitory effects. 3. Oxytocin (10 nM) applied in Ca(2+)-containing solution induced rhythmic increases in both force and [Ca2+]i. CPA (10 microM) had no effect on oxytocin-induced rhythmic contractions. 4. At a high concentration (300 microM), CPA inhibited the rhythmic contractions induced by 10 nM oxytocin; the frequency and the peak height were decreased, and in many bundles contractions were completely abolished. These inhibitory effects were reversed after CPA washout. 5. CPA (300 microM) inhibited the rate of rise of [Ca2+]i due to depolarization induced by high-K(+)-containing solution. 6. These results suggest that low concentrations of CPA inhibit the loading of Ca2+ into intracellular stores in intact tissue strips, and that the Ca2+ stores are not directly involved in the uterine rhythmic contractions. It is also suggested that a high concentration of CPA inhibits the mechanism that is responsible for the generation of rhythmic contractions as well as voltage-dependent Ca2+ channels.

General pharmacological profile of the new cognition-enhancing agent nefiracetam

The general pharmacological properties of a novel cognition-enhancing agent, nefiracetam (N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl)acetamide, DM-9384, CAS 77191-36-7) were investigated, and the following results were obtained. 1. Central nervous system: Nefiracetam showed depressant activities (such as ataxia) on general behavior (mice), and inhibited spontaneous locomotor activity, rota-rod and traction performances (mice) and polysynaptic potential of the spinal reflex (rats), and potentiated pentobarbital anesthesia (mice). The drug inhibited electroshock-induced seizure at relatively low doses, but did not affect chemoshock-induced seizure (mice). Nefiracetam failed to show analgesic activity in the tail pinch test, but inhibited the acetic acid-induced writhing syndrome (mice). An inhibitory pattern in the electroencephalogram was observed (cats). Nefiracetam had little or no effect on body temperature (rats). 2. Respiratory and cardiovascular systems: Nefiracetam induced transient decreases in blood pressure, left ventricular pressure and LV dp/dt max at higher doses (dogs). 3. Autonomic nervous system: Nefiracetam had no influence on pupil size (rabbits). The drug induced no significant effect on the pressor response to norepinephrine or depressor response to acetylcholine, but inhibited the contractile response of the nictitating membrane to preganglionic cervical sympathetic nerve stimulation at the highest dose (dogs). 4. Gastrointestinal system: Nefiracetam inhibited gastrointestinal propulsion (mice), gastric emptying rate and gastric secretion (rats) at higher doses. Nefiracetam produced no apparent damage in the gastric mucosa, and had no effect on bile secretion (rats). 5. Isolated smooth muscle: Nefiracetam had no effect on the resting tonus of isolated ileum, whereas it inhibited the contractile response to acetylcholine, histamine, serotonin, nicotine and BaCl2 at higher concentrations (guinea pigs). Nefiracetam had no effect on the resting tonus or the serotonin-induced contraction of stomach fundus (rats). The drug had no effect on the resting tonus or the norepinephrine-induced contraction of vas deferens, but tended to inhibit the contraction induced by nerve stimulation (guinea pigs). Nefiracetam had little or no effect on the resting tonus or oxytocin-induced contraction of virgin uterus, or on spontaneous contraction of pregnant uterus (rats). Nefiracetam did not affect the resting tonus of trachea, whereas it inhibited isoproterenol-induced relaxation at the highest concentration (guinea pigs). Nefiracetam had no chronotropic effect in isolated atria, but showed a slight negative inotropic effect at the highest concentration (guinea pigs). 6. Miscellaneous: Nefiracetam slightly decreased urinary volume, whereas it did not affect urinary electrolyte excretion (rats).(ABSTRACT TRUNCATED AT 400 WORDS)

Aphidicolin potentiates apoptosis induced by arabinosyl nucleosides in human myeloid leukemia cell lines

We investigated the effect of aphidicolin, an inhibitor of DNA polymerase alpha and delta, on the induction of apoptosis by arabinosyl nucleosides in a human promyelocytic leukemia cell line, HL-60. Pretreatment of HL-60 cells with aphidicolin (2 microM) significantly increased the number of morphologically apoptotic cells induced by 1-beta-D arabinofuranosylcytosine (ara-C) during 4 hr of incubation. This is consistent with the appearance of DNA fragmentation as determined quantitatively by diphenylamine or by agarose gel electrophoresis. The inhibition of cell growth on day 3 after drug exposure was correlated with the degree of apoptosis: Such synergistic interaction between aphidicolin and ara-C has also been observed in other human myeloid leukemia cell lines, U937 and KG-1. In addition, the induction of apoptosis by 9-beta-D arabinofuranosyladenine or 9-beta-D arabinofuranosylguanine is augmented by aphidicolin.

Immortalization of normal human salivary gland cells with duct-, myoepithelial-, acinar-, or squamous phenotype by transfection with SV40 ori- mutant deoxyribonucleic acid

BACKGROUND

Based on morphologic and functional differences mainly, 4 distinct types of cells are recognized in human salivary glands. For a better understanding of cellular proliferation and differentiation of human salivary glands as well as carcinogenesis of salivary gland neoplasms, we attempted to establish normal human salivary gland cells in an in vitro system.

EXPERIMENTAL DESIGN

Primary cultured human salivary gland cells were transfected with origin-defective mutant DNA of SV40. After 2 to 3 weeks of transfection, slowly expanding colonies consisting of small compact cells emerged, whereas mock-transfected cells did not grow any more and eventually entered crisis, followed by cell death.

RESULTS

Using limited dilution technique, we isolated 4 cell clones with distinct morphology from a single colony. Morphologic observation of cells cultured on plastic dishes precisely revealed the characteristics of constituent cells of salivary glands; i.e., three cell clones showing cuboidal (NS-SV-DC), spindle (NS-SV-MC), and flattened (NS-SV-SC) morphology were similar to duct, myoepithelial, and squamous cells, respectively. A remaining cell clone showing polygonal in shape with numerous secretory granules (NS-SV-AC) resembled acinar cells. Characterization of cell clones by the ultrastructural examination and the search for specific antigens showed the similarity of NS-SV-DC, NS-SV-MC, NS-SV-AC, and NS-SV-SC to duct, myoepithelial, acinar, and squamous cells, respectively. Integration and expression of SV40 DNA were confirmed by Southern blot and indirect immunofluorescence staining. Anchorage-independent growth in soft-agar and tumorigenicity in nude mice were not recognized in all cell clones.

CONCLUSIONS

These results demonstrate that establishment of cell clones with duct-, myoepithelial-, acinar-, or squamous phenotype was accomplished in the in vitro system, and that based on the evaluation of colony-forming ability in soft-agar and tumorigenicity in nude mice, these cell clones are considered to be non-neoplastic.

Enzyme immunoassay of liver-type arginase and its potential clinical application

We developed an efficient enzyme-linked immunosorbent assay (ELISA) system for measurement of human liver-type arginase in serum. A conjugate of the Fab' fragment of anti-human liver (recombinant) arginase IgG and horseradish peroxidase was used as the second antibody. This assay is highly specific, sensitive, and reproducible, enabling us to detect arginase at concentrations as low as several micrograms per liter without any prior processing of serum. The reaction is linear up to 200 micrograms/L. The arginase concentration in serum, as determined by this method, increased markedly and temporarily at the time of surgical operation or later injury to the liver. The increase was accompanied or followed by increases in serum concentrations of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, suggesting that the arginase emerged from damaged hepatocytes. In view of a limited tissue distribution of liver-type arginase, our ELISA system may be useful in diagnosis of various hepatic disorders as well as follow-up of postoperative conditions of patients.

Enzyme immunoassay of liver-type arginase and its potential clinical application

We developed an efficient enzyme-linked immunosorbent assay (ELISA) system for measurement of human liver-type arginase in serum. A conjugate of the Fab' fragment of anti-human liver (recombinant) arginase IgG and horseradish peroxidase was used as the second antibody. This assay is highly specific, sensitive, and reproducible, enabling us to detect arginase at concentrations as low as several micrograms per liter without any prior processing of serum. The reaction is linear up to 200 micrograms/L. The arginase concentration in serum, as determined by this method, increased markedly and temporarily at the time of surgical operation or later injury to the liver. The increase was accompanied or followed by increases in serum concentrations of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase, suggesting that the arginase emerged from damaged hepatocytes. In view of a limited tissue distribution of liver-type arginase, our ELISA system may be useful in diagnosis of various hepatic disorders as well as follow-up of postoperative conditions of patients.

General pharmacological profile of the new anti-ulcer drug 3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl]methyl]-amino-N -methylbenzamide

Pharmacological properties of the anti-ulcer drug 3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl] methyl]-amino-N-methylbenzamide (DQ-2511, CAS 104775-36-2) on the central and autonomic nervous systems, smooth muscle, gastrointestinal system, and other miscellaneous systems were investigated. 1. DQ-2511 showed little or no influence on general behavior, spontaneous motor activity, hexobarbital sleeping time (mouse), conditioned avoidance response (rat), body temperature (rabbit), EEG or spinal reflex (cat) after oral administration (300-1000 mg/kg) or intravenous injection (15, 50 mg/kg). It also had no anticonvulsant or analgesic activities (mouse). 2. DQ-2511 had no influence on pupil size (rabbit). It reduced or tended to reduce contractile responses of the nictitating membrane induced by electrical stimulation of pre- and post-ganglionic sympathetic nerve (cat) at the highest dose. The drug inhibited the pressor response to norepinephrine, but had little or no inhibitory effect on the depressor response to acetylcholine at the highest dose (dog). 3. DQ-2511 reduced contractile responses to nicotine, BaCl2, acetylcholine, histamine and serotonin (isolated guinea pig ileum), to acetylcholine and histamine (trachea), and to norepinephrine (vas deferens) at high concentrations. It also inhibited spontaneous and oxytocin-induced motility (isolated rat uterus). 4. DQ-2511 decreased gastric motility in a dose-related manner at intravenous doses of 5-50 mg/kg (dog). It also reduced gastric emptying rate at oral doses of 100-1000 mg/kg, and gastric secretion at intraperitoneal doses of 100-300 mg/kg (rat). On the other hand, it induced no definite changes in intestinal motility (dog) or gastrointestinal transit (mouse).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of high-dose methotrexate on plasma hypoxanthine and uridine levels in patients with acute leukemia or non-Hodgkin lymphoma in childhood

We investigated the effect of high dose methotrexate (HDMTX) therapy on plasma hypoxanthine (Hx) and uridine (UR) concentrations in 12 children with acute lymphoblastic leukemia (ALL) or non-Hodgkin lymphoma (NHL). The initial plasma Hx level before the first administration of HDMTX (1 g/m2) was significantly higher in patients (25.5 +/- 17.5 microM) than that in healthy adult controls (4.0 +/- 1.4 microM). By 48 or 72 hours after the beginning of MTX infusion, the Hx concentration had decreased to 7.9 +/- 7.7 microM and 4.7 +/- 4.1 microM, respectively. This decrease of plasma Hx concentration after MTX infusion was also observed with the second course of HDMTX (3 g/m2) therapy. On the other hand, the plasma UR level did not change significantly. The in vitro treatment with 2 microM MTX of hypoxanthine-guanine phosphoribosyltransferase (HGPRT)-deficient mutant cells selected from HL-60 lowered the excretion of Hx into the culture medium. These data suggest a possible new explanation of the synergism of HDMTX and 6-thiopurines, for example 6-mercaptopurine and 6-thioguanine, since plasma Hx is considered to counteract 6-thiopurine toxicity through competition at the level of HGPRT.

Molecular cloning of murine monoclonal anti-idiotypic Fab

Anti-idiotypic antibodies (Ab2) binding to idiotopes on antibodies with various antigen binding specificities (Ab1) are potential regulators of immunity in a variety of diseases, such as autoimmunity, cancer, and viral, bacterial, or parasitic infections. Furthermore, Ab2 are useful probes for the characterization of receptor/ligand interactions. Thus far, Ab2 production has been limited to the isolation of polyclonal Ab2 from immune sera or monoclonal Ab2 from hybridoma supernatants. However, both approaches have produced a limited number of Ab2. As an alternative approach, we demonstrate here the production of Ab2-Fab by using repertoire cloning. Using HIV-1 as a model system, the Ab2-Fab were generated from the spleens of mice immunized with the virus-neutralizing and syncytia-inhibiting anti-HIV-1 monoclonal antibody 0.5 beta. A bacteriophage lambda vector system was used to express a combinatorial library in Escherichia coli. Iodinated 0.5 beta was used to identify 17 Ab2-Fab clones. DNA sequence analysis of five clones revealed three similar kappa and Fd combinations. The Ab2-Fab bound with high affinity (3.5-6.5 x 10(9) liters/mol) specifically to the Ab1 and not to isotype-matched antibodies with unrelated specificities. The three Ab2-Fab probably bind to the same idiotope on the Ab1 as demonstrated in cross-competition binding studies. The Ab2-Fab inhibited binding of the Ab1 to antigen, and therefore, may functionally mimic the epitope defined by the Ab1. Repertoire cloning of Ab2-Fab may facilitate the generation of Ab2 that have potential as modulators of immune responses against various antigens.

Involvement of p53 mutation in the development of human salivary gland pleomorphic adenomas

We examined the status of the p53 mutation, a putative tumor suppressor gene, as well as the expressions of myc and mos oncogene products in human salivary gland pleomorphic adenoma cells in culture derived from four individuals using techniques which enabled selective and favourable growths of tumor cells. Culture techniques empolyed in this study consisted of type I collagen gel-coated dishes and serum-free medium as substrates and growth medium, respectively. Cells grown under above conditions were subjected to the analyses of p53, myc and mos expression. When analyzed by both immunocytochemical staining and immunoblot, mutant forms of p53 specifically detected by PAb240 were observed in three of 4 cases. However, none of the 4 cases expressed myc and mos oncogene products. These results may imply a role for p53 mutation in the development of human salivary gland pleomorphic adenomas.

Anatomy of an unusual RNA polymerase II promoter containing a downstream TATA element

The adenovirus type 2 IVa2 promoter lacks a conventional TATA element yet directs transcription from two closely spaced initiation sites. To define elements required for in vitro transcription of this promoter, IVa2 templates carrying 5' deletions or linker-scanning mutations were transcribed in HeLa whole-cell extracts and the transcripts were analyzed by primer extension. Mutation of the sequence centered on position -47, which is specifically recognized by a cellular factor, reduced the efficiency of IVa2 transcription two- to threefold, whereas mutation of the sequence centered on position -30 selectively impaired utilization of the minor in vivo initiation site. Utilization of the major in vivo site was decreased no more than fivefold by deletion of all sequences upstream of position -15. By contrast, mutation of the region from +13 to +19 or of the initiation region severely impaired IVa2 transcription. The sequence spanning the initiation sites was sufficient to direct accurate initiation by RNA polymerase II from the major in vivo site. Thus, the two initiation sites of the IVa2 promoter are specified by independent elements, and a downstream element is the primary determinant of efficient transcription from both of these sites. The downstream element identified by mutational analysis altered the TATA element-like sequence TATAGAAA lying at positions +21 to +14 in the coding strand. Transcription from the wild-type IVa2 promoter was severely inhibited when endogenous TFIID was inactivated by mild heat treatment. Exogenous human TATA-binding protein (TBP) synthesized in Escherichia coli restored specific IVa2 transcription from both initiation sites when added to such heat-treated extracts. Although efficient IVa2 transcription requires both the downstream TATA sequence and active TFIID, bacterially synthesized TBP also stimulated the low level of IVa2 transcription observed when the TATA sequence was mutated to a sequence that failed to bind TBP.

Dorsal-ventral patterning in Drosophila: DNA binding of snail protein to the single-minded gene

The Drosophila snail gene is required for proper mesodermal development. Genetic studies suggest that it functions by repressing adjacent ectodermal gene expression including that of the single-minded (sim) gene. The snail gene encodes a protein with a zinc-finger motif, and here we report that the snail gene product is a sequence-specific DNA binding protein. The snail protein recognizes a 14-base-pair consensus sequence that is found nine times in a 2.8-kilobase sim regulatory region. These results provide evidence for the direct control of sim transcription by snail.

Pre-treatment of a human T-lymphoblastoid cell line with L-asparaginase reduces etoposide-induced DNA strand breakage and cytotoxicity

The effect of L-asparaginase (L-asp) pre-treatment on etoposide-induced DNA strand breakage and cytotoxicity was investigated. In a T-lymphoblastoid cell line, Molt 4, etoposide-induced DNA strand breaks, DNA-protein cross-links and cytotoxicity were reduced by pre-treatment with L-asp for 15 hr, but it did not cause these changes in a promyelocytic-leukemia cell line, HL-60, which is less sensitive than Molt 4 to L-asp. However, pre-treatment of Molt 4 cells with L-asp did not significantly alter the accumulation of [3H]-etoposide. Cell-cycle analyses showed an increase in G1-phase cells, a significant decrease in both S-phase cells and G2/M-phase cells pre-treated with L-asp in Molt 4 cells, but L-asp exposure did not result in any significant changes in HL-60 cells. On the other hand, L-asp pre-treatment did not affect topoisomerase-I (Topo-I) inhibitor, camptothecin (CPT)-induced DNA strand breaks or toxicity in Molt 4 cells. Our data imply that a decrease in S- and G2/M-phase cells following L-asp treatment may explain the reduction of etoposide-induced DNA lesions and cytotoxicity in Molt 4 cells, since topoisomerase-II (Topo-II) content or activity is a function of cellular proliferation status.

Baculovirus recombinant expressing a secreted form of a transmembrane carcinoma-associated antigen

GA733-2 is a monoclonal antibody-defined, 40-kDa glycoprotein antigen that is associated with carcinomas of various origins. Hydrophobicity analysis of the protein sequence predicted by complementary DNA (cDNA) has suggested that the GA733-2 antigen is a type I membrane protein. In this study, the polymerase chain reaction was used in a strategy to omit cDNA sequences for the transmembrane and cytoplasmic domains, thereby converting the extracellular domain into a secretory protein. Full-length and truncated cDNAs were cloned into the baculovirus transfer vector pVL1392 and introduced into Autographa californica nuclear polyhedrosis virus by homologous recombination. The full-length cDNA baculovirus recombinant directed the expression of a 40-kDa glycoprotein that was confined to infected Spodoptera frugiperda cells, whereas cells infected with the truncated cDNA baculovirus recombinant abundantly secreted a 31-kDa glycoprotein into the culture medium. Recombinant secretory antigen displayed an in vitro immunoreactivity to monoclonal antibody and an in vivo immunogenicity in mice that were similar to native antigen. The facile purification of mg quantities of carcinoma-associated antigen will enable an evaluation of its immunogenicity in cancer patients.

Early diagnosis of leukoencephalopathy of acute lymphocytic leukemia by MRI

Using repeated computed tomographic and magnetic resonance imaging scans, we examined 8 patients with acute lymphocytic leukemia during remission induction therapy between 1988 and 1989. In 3 patients, leukoencephalopathy was diagnosed by T2-weighted magnetic resonance imaging. In 1 patient, leukoencephalopathy was progressive and irreversible brain damage and mental retardation persisted. In the other 2 patients, hyperintense lesions in the periventricular white matter were transient and no neurologic sequelae ensued. Magnetic resonance imaging was more useful than computed tomography in the early diagnosis and management of these acute lymphocytic leukemia patients with leukoencephalopathy.