151
|
Soh MS, Kim YM, Han SJ, Song PS. REP1, a basic helix-loop-helix protein, is required for a branch pathway of phytochrome A signaling in arabidopsis. THE PLANT CELL 2000; 12:2061-74. [PMID: 11090209 PMCID: PMC150158 DOI: 10.1105/tpc.12.11.2061] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2000] [Accepted: 09/19/2000] [Indexed: 05/18/2023]
Abstract
Phytochromes are primary photoreceptors mediating diverse responses ranging from induction of germination to floral induction in higher plants. We have isolated novel recessive rep1 (reduced phytochrome signaling 1) mutants, which exhibit a long-hypocotyl phenotype only under far-red light but not under red light. Physiological characterization showed that rep1 mutations greatly reduced a subset of phytochrome A-regulated responses, including the inhibition of hypocotyl elongation, cotyledon expansion, modulation of gravitropic growth of hypocotyl, and induction of the CAB (encoding chlorophyll a/b binding protein) gene, without affecting the accumulation of anthocyanin, far-red-preconditioned blocking of greening, induction of germination, and induction of CHS (encoding chalcone synthase) and FNR (encoding ferredoxin-NADP(+) oxidoreductase) genes. These results suggest that REP1 is a positive signaling component, functioning in a branch of the phytochrome A signaling pathway. Molecular cloning and characterization of the REP1 gene revealed that it encodes a light-inducible, putative transcription factor containing the basic helix-loop-helix motif.
Collapse
|
152
|
Seo WG, Pae HO, Kim NY, Oh GS, Park IS, Kim YH, Kim YM, Lee YH, Jun CD, Chung HT. Synergistic cooperation between water-soluble chitosan oligomers and interferon-gamma for induction of nitric oxide synthesis and tumoricidal activity in murine peritoneal macrophages. Cancer Lett 2000; 159:189-95. [PMID: 10996731 DOI: 10.1016/s0304-3835(00)00551-6] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of water-soluble chitosan oligomers (WSCO) on the synthesis of nitric oxide (NO) by murine peritoneal macrophages and on macrophage-mediated cytotoxicity towards murine fibrosarcoma Meth A cells were investigated. WSCO alone had no effect on NO synthesis and killing of tumor cells. However, treatment of macrophages with a combination of WSCO and interferon-gamma (IFN-gamma) synergically increased NO synthesis and enhanced killing of tumor cells. The synergism between IFN-gamma and WSCO in NO synthesis and tumoricidal activity was mainly dependent on increased secretion of tumor necrosis factor-alpha by WSCO.
Collapse
MESH Headings
- Animals
- Antibodies, Monoclonal/pharmacology
- Chitin/analogs & derivatives
- Chitin/pharmacology
- Chitosan
- Culture Media, Conditioned/pharmacology
- Cytotoxicity, Immunologic/drug effects
- Dose-Response Relationship, Drug
- Drug Synergism
- Interferon-gamma/pharmacology
- Macrophages, Peritoneal/drug effects
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Mice
- Mice, Inbred C57BL
- Nitric Oxide/biosynthesis
- Nitric Oxide Synthase/drug effects
- Nitric Oxide Synthase/metabolism
- Nitric Oxide Synthase Type II
- Solubility
- Tumor Cells, Cultured/cytology
- Tumor Cells, Cultured/drug effects
- Tumor Necrosis Factor-alpha/immunology
- Tumor Necrosis Factor-alpha/metabolism
Collapse
|
153
|
Kim NY, Pae HO, Kim YC, Choi CK, Rim JS, Lee HS, Kim YM, Chung HT. Pentoxifylline potentiates nitric oxide production in interleukin-1beta-stimulated vascular smooth muscle cells through cyclic AMP-dependent protein kinase A pathway. GENERAL PHARMACOLOGY 2000; 35:205-11. [PMID: 11827727 DOI: 10.1016/s0306-3623(01)00108-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In the present study, we observed that pentoxifylline (PTX) significantly augmented the nitric oxide (NO) production and the iNOS gene expression by interleukin-1beta (IL-1beta)-stimulated vascular smooth muscle cells (VSMCs). The enhancing effects of PTX on the IL-1beta-induced NO production was associated with an increased intracellular cyclic AMP (cAMP) levels, and the synergistic effects of PTX on the IL-1beta-induced NO production was blocked by cAMP-dependent protein kinase A (PKA) inhibitors. PKA inhibitors, KT5720 and H89, markedly decreased the augmented expression of iNOS gene whereas ODQ, a soluble guanylate cyclase inhibitor, did not affect the enhancing effect. In addition, the pretreatment with KT5720 or H89 abolished the increased translocation of the p65 subunit of NF-kappaB into the nucleus by PTX in the IL-1beta-stimulated VSMCs. These results suggest that enhancing effects of PTX on the iNOS gene expression in the IL-1beta-stimulated VSMCs is mediated predominantly through the activation of NF-kappaB via cAMP-dependent PKA pathway.
Collapse
|
154
|
Kim YM, Jang JW, Lee OH, Yeon J, Choi EY, Kim KW, Lee ST, Kwon YG. Endostatin inhibits endothelial and tumor cellular invasion by blocking the activation and catalytic activity of matrix metalloproteinase. Cancer Res 2000; 60:5410-3. [PMID: 11034081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Here we report the inhibition of cellular invasion by a recombinant mouse endostatin and the possible mechanism of the inhibition. Endostatin significantly reduced endothelial as well as tumor cellular invasion into the reconstituted basement membrane in vitro. Gelatin zymographic analysis revealed that the activation of promatrix metalloproteinase-2 (proMMP-2) that was secreted from endothelial cells was blocked upon endostatin treatment. Studies with recombinant MMPs confirmed that endostatin inhibited proMMP-2 activation, mediated by both membrane-type 1 MMP and 4-aminophenylmercuric acetate. Furthermore, enzymatic assays using a peptide substrate demonstrated that endostatin inhibited the catalytic activities of both MMP-2 and membrane-type 1 MMP. Finally, coimmunoprecipitation experiments revealed that endostatin formed a stable complex with proMMP-2. These novel findings would, at least in part, explain the mechanism of the potent antiangiogenic and antitumor activities of endostatin.
Collapse
|
155
|
Kim YM, Kim TH, Chung HT, Talanian RV, Yin XM, Billiar TR. Nitric oxide prevents tumor necrosis factor alpha-induced rat hepatocyte apoptosis by the interruption of mitochondrial apoptotic signaling through S-nitrosylation of caspase-8. Hepatology 2000; 32:770-8. [PMID: 11003621 DOI: 10.1053/jhep.2000.18291] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mitochondrial cytochrome c release plays a critical role in apoptotic signal cascade after the activation of cell surface death receptors. We investigated the role played by nitric oxide (NO) in mitochondrial apoptotic signaling in tumor necrosis factor alpha (TNF-alpha) plus actinomycin D (TNF-alpha/ActD)-induced apoptosis. NO produced either by S-nitroso-N-acetyl-DL-penicillamine (SNAP) or inducible NO synthase (iNOS) prevented TNF-alpha/ActD-induced apoptosis in hepatocytes and also inhibited both caspase-8-like (IETDase) and caspase-3-like protease (DEVDase) activity as well as mitochondrial cytochrome c release. Recombinant human (rh) caspase-8 induced the cleavage of the cytochrome c-effluxing factor Bid and cytochrome c release from purified mitochondria in the reconstitution system with Bid(+/+) cytosol, but not with Bid(-/-) cytosol. The addition of SNAP and the caspase-8 inhibitor Ac-IETD-fmk inhibited caspase-8-dependent Bid cleavage and cytochrome c release. The inhibitory effect of NO on caspase-8 was reversed by dithiothreitol (DTT). Furthermore, rh-caspase-8 was found to be modified by S-nitrosylation with 1.7 moles of NO bound per mole of enzyme. Treatment of hepatocytes with interleukin 1beta (IL-1beta) plus interferon gamma (IFN-gamma), which induced iNOS expression and NO production, suppressed TNF-alpha/ActD-induced Bid cleavage and mitochondrial cytochrome c release. The NOS inhibitor N(G)-monomethyl-L-arginine (NMA) inhibited the protective effects of IL-1beta and IFN-gamma. The liver-specific NO donor V-PYRRO/NO also inhibited in vivo elevation of IETDase activity, Bid cleavage, and mitochondrial cytochrome c release in the livers of rats injected with TNF-alpha plus D-galactosamine. Our results indicate that one mechanism by which NO protects hepatocytes from TNF-alpha/ActD-induced apoptosis is via the interruption of mitochondrial apoptotic signaling through S-nitrosylation of caspase-8.
Collapse
|
156
|
Joh CW, Park CH, Kang HJ, Oh YT, Kim HS, Choi BI, Park KB, Kim YM, Kim KH, Vahc YW, Jang JS, Lee BK. Measurement of radiation absorbed dose in endovascular Ho-166 brachytherapy using a balloon angio-catheter. Nucl Med Commun 2000; 21:959-64. [PMID: 11130338 DOI: 10.1097/00006231-200010000-00011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The purpose of this study was to estimate the absorbed dose distribution of Ho-166 endovascular beta irradiation using an angio-catheter. The liquid form of Ho-166 was produced at the Korea Atomic Energy Research Institute (KAERI) by an (n,gamma) reaction. Ho-166 has a half-life of 26.8 h and emits a high-energy beta particle with a maximum energy of 1.85 MeV. GafChromic film was used for the estimation of the absorbed dose of beta particles. A Co-60 teletherapy source and a 6 MV photon beam from a linear accelerator were used to generate dose-optical density calibration curves. The exposed films were read using a videodensitometer. With a modified micrometer, the film was positioned accurately on the surface of the balloon in water. The balloon was filled with Ho-166 solution to a pressure of 4 atm. Several film exposures were made with varying irradiation times and activities. The radiation absorbed dose rates were 1.02, 0.51 and 0.35 Gy x min(-1) x GBq(-1) x ml(-1) at the balloon surface, 0.5 and 1 mm from the balloon surface, respectively. The absorbed dose distribution revealed that Ho-166 is a good source for endovascular irradiation as the beta range is very short, avoiding unnecessary irradiation of normal tissue. A clinically applicable irradiation and duration of exposure were achievable utilizing our system.
Collapse
|
157
|
Kim YM, Im JY, Han SH, Kang HS, Choi I. IFN-gamma up-regulates IL-18 gene expression via IFN consensus sequence-binding protein and activator protein-1 elements in macrophages. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:3198-205. [PMID: 10975835 DOI: 10.4049/jimmunol.165.6.3198] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Constitutive IL-18 expression is detected from many different cells, including macrophages, keratinocytes, and osteoblasts. It has been known that IL-18 gene expression is regulated by two different promoters (p1 promoter and p2 promoter). When RAW 264.7 macrophages were treated with IFN-gamma, IL-18 gene expression was increased in a dose- and time-dependent manner. IFN-gamma activated the inducible promoter 1, but not the constitutive promoter 2. Mutagenesis studies indicated that an IFN consensus sequence-binding protein (ICSBP) binding site between -39 and -22 was critical for the IFN-gamma inducibility. EMSA using an ICSBP oligonucleotide probe showed that IFN-gamma treatment increased the formation of DNA-binding complex, which was supershifted with anti-IFN regulatory factor-1 Ab and anti-ICSBP Ab. Another element, an AP-1 site between -1120 and -1083, was important. EMSA using an AP-1-specific oligonucleotide demonstrated that IFN-gamma or LPS treatment increased the AP-1-binding activity. The addition of anti-c-Jun Ab or anti-c-Fos Ab to IFN-gamma- or LPS-treated nuclear extracts resulted in the reduction of AP-1 complex or the formation of a supershifted complex. Taken together, these results indicate that IFN-gamma increased IL-18 gene expression via ICSBP and AP-1 elements.
Collapse
|
158
|
Nam DH, Wang KC, Kim YM, Chi JG, Kim SK, Cho BK. The effect of isochromosome 17q presence, proliferative and apoptotic indices, expression of c-erbB-2, bcl-2 and p53 proteins on the prognosis of medulloblastoma. J Korean Med Sci 2000; 15:452-6. [PMID: 10983696 PMCID: PMC3054657 DOI: 10.3346/jkms.2000.15.4.452] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Medulloblastoma accounts for 20 to 25% of all intracranial neoplasms in children. The significance of the presence of isochromosome 17q (i(17q)), proliferative potential, apoptotic activity, and expression of c-erbB-2, bd-2, and p53 proteins in predicting long-term survival of patients with medulloblastomas was investigated. Twenty children were divided into two groups (favorable and poor outcome groups). Ten children with favorable outcome (FO) were disease-free during the follow-up period (median: 61.5 months). The other ten children with poor outcome (PO) died of disease progression, having a median survival of 18 months. Fluorescent in situ hybridization (FISH) for i(17q), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and immunohistochemistry for Ki-67, c-erbB-2, bcl-2, and p53 proteins was performed in these patients. Nine out of 17 children showed i(17q). There was no difference in the rate of positive i(17q) between the FO and PO groups. The presence of i(17q) was not significantly related to biological factors that we investigated. Unlike the prominent presence of the proliferative potential and p53 expression in children with PO, apoptotic activity and expression of c-erbB-2 and bcl-2 had no correlation with the outcome.
Collapse
|
159
|
Kim YM, Ziegler DM. Size limits of thiocarbamides accepted as substrates by human flavin-containing monooxygenase 1. Drug Metab Dispos 2000; 28:1003-6. [PMID: 10901713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Microsomes isolated from Spodoptera frugiperda (Sf)9 cells infected with human flavin-containing monooxygenase (FMO)1 recombinant baculovirus catalyzed the NADPH- and O2-dependent oxidation of methimazole, thiourea, and phenylthiourea. However, there was no detectable activity with 1,3-diphenylthiourea or larger thiocarbamides. Microsomes from control Sf9 cells were devoid of methimazole or thiourea S-oxygenase activity. Trimethylamine up to 1.0 mM had no detectable effect on the oxidation of 10 microM methimazole (Km = 5 microM) but 1.0 mM N,N-dimethylaniline or chlorpromazine inhibited the oxidation of 1.0 mM methimazole 50 and 70%, respectively. Although products were not isolated, the pronounced inhibition of methimazole S-oxygenation suggests that these amines are alternate substrates for human FMO1. Because 1,3-diphenylthiourea is apparently completely excluded from the catalytic site, tricyclic amine drugs are probably approaching the upper size limits of xenobiotics accepted by human FMO1. The substrate specificity of this isoform in humans appears considerably more restricted than that of pig or guinea pig FMO1. Differences in the size of nucleophiles accepted must be considered in attempting to extrapolate the extensive structure-activity studies available for pig FMO1 to this FMO isoform in humans.
Collapse
|
160
|
Kim YM, Oh HC, Kim HJ. The pattern of bone marrow oedema on MRI in osteonecrosis of the femoral head. THE JOURNAL OF BONE AND JOINT SURGERY. BRITISH VOLUME 2000; 82:837-41. [PMID: 10990307 DOI: 10.1302/0301-620x.82b6.10740] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
It has been suggested that transient osteoporosis or the bone marrow oedema syndrome (BMOS) may be the initial phase of osteonecrosis of the femoral head (ONFH) and that there may be a common pathophysiology. In this study, we have assessed the MR images of 200 consecutive patients with ONFH in respect of the BMO pattern in order to test this hypothesis. This pattern was not observed in the early stage of ONFH. The initial abnormal finding detected on the MR images was an abnormal band of intensity at the junction between the necrotic area and the normal bone. Structural damage of the head seems to result in the appearance of the BMO pattern and the development of pain in ONFH. There was no finding to support the existence of a continuum between BMOS and ONFH.
Collapse
|
161
|
Zhou X, Gordon SA, Kim YM, Hoffman RA, Chen Y, Zhang XR, Simmons RL, Ford HR. Nitric oxide induces thymocyte apoptosis via a caspase-1-dependent mechanism. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:1252-8. [PMID: 10903723 DOI: 10.4049/jimmunol.165.3.1252] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We previously showed that NO induces apoptosis in thymocytes via a p53-dependent pathway. In the present study, we investigated the role of caspases in this process. The pan-caspase inhibitor, ZVAD-fmk, and the caspase-1 inhibitor, Ac-YVAD-cho, both inhibited NO-induced thymocyte apoptosis in a dose-dependent manner, whereas the caspase-3 inhibitor, Ac-DEVD-cho, had little effect even at concentrations up to 500 microM. ZVAD-fmk and Ac-YVAD-cho were able to inhibit apoptosis when added up to 12 h, but not 16 h, after treatment with the NO donor S-nitroso-N-acetyl penicillamine (SNAP). Caspase-1 activity was up-regulated at 4 h and 8 h and returned to baseline by 24 h; caspase-3 activity was not detected. Cytosolic fractions from SNAP-treated thymocytes cleaved the inhibitor of caspase-activated deoxyribonuclease. Such cleavage was completely blocked by Ac-YVAD-cho, but not by Ac-DEVD-cho or DEVD-fmk. Poly(ADP-ribose) polymerase (PARP) was also cleaved in thymocytes 8 h and 12 h after SNAP treatment; addition of Ac-YVAD-cho to the cultures blocked PARP cleavage. Furthermore, SNAP induced apoptosis in 44% of thymocytes from wild-type mice; thymocytes from caspase-1 knockout mice were more resistant to NO-induced apoptosis. These data suggest that NO induces apoptosis in thymocytes via a caspase-1-dependent but not caspase-3-dependent pathway. Caspase-1 alone can cleave inhibitor of caspase-activated deoxyribonuclease and lead to DNA fragmentation, thus providing a novel pathway for NO-induced thymocyte apoptosis.
Collapse
|
162
|
Jung YJ, Lee JS, Kim YM. Synthesis and in vitro/in vivo evaluation of 5-aminosalicyl-glycine as a colon-specific prodrug of 5-aminosalicylic acid. J Pharm Sci 2000. [PMID: 10756325 DOI: 10.1002/(sici)1520-6017(200005)89:53.0.co;2-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A simple synthetic route for the preparation of amino acid conjugate of 5-aminosalicylic acid (5-ASA) was exploited and prepared 5-aminosalicyl-glycine (5-ASA-Gly) in good yield. In vitro and in vivo properties of 5-ASA-Gly as a colon-specific prodrug of 5-ASA were investigated using rats as the test animal. Incubation of 5-ASA-Gly with cecal or colonic contents at 37 degrees C released 5-ASA in 65 or 27% of the dose in 8 h, respectively. No 5-ASA was detected from the incubation of 5-ASA-Gly with the homogenates of stomach or small intestine. Plasma concentration of 5-ASA-Gly decreased rapidly after intravenous administration of 5-ASA-Gly, and no 5-ASA was detected in the blood, which indicated 5-ASA-Gly was not degraded in the plasma. After oral administration of 5-ASA-Gly, about 50% of the administered dose was recovered as 5-ASA and N-acetyl-ASA and 3% as 5-ASA-Gly from feces and 14% as 5-ASA-Gly and 28% as 5-ASA and N-acetyl-ASA from urine in 24 h. These results suggested that a large fraction of 5-ASA-Gly was delivered to the large intestine and activated to liberate 5-ASA. For comparison, total recovery of 5-ASA and N-acetyl-5-ASA from feces after oral administration of 5-ASA-Gly was greater than that from sulfasalazine, which is one of the most commonly prescribed prodrugs of 5-ASA.
Collapse
|
163
|
Kwon TW, Kim YM, Song SJ, Kwon YU, Chung SK. Synthesis of thiophenyl substituted cyclohexa-2,4-dien-1-one and its photocleavage coupling reaction with amines. Bioorg Med Chem Lett 2000; 10:1551-3. [PMID: 10915048 DOI: 10.1016/s0960-894x(00)00291-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Thiophenyl substituted cyclohexa-2,4-dien-1-ones were synthesized and photolyzed in the presence of various amines to afford the amides containing diene moeties via the ketene intermediate under visible light irradiation at 38 degrees C.
Collapse
|
164
|
Bönig H, Laws HJ, Wundes A, Verheyen J, Hannen M, Kim YM, Banning U, Nürnberger W, Körholz D. In vivo cytokine responses to interleukin-2 immunotherapy after autologous stem cell transplantation in children with solid tumors. Bone Marrow Transplant 2000; 26:91-6. [PMID: 10918410 DOI: 10.1038/sj.bmt.1702431] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The potent immunostimulatory cytokine interleukin-2 (IL-2) has been extensively investigated for its potential to induce anti-tumor immunity in a number of tumor models. Only recently the complex interplay of mutually suppressive or supportive cytokines of the IL-2-induced network of cytokines has been better characterized. The aim of this study was to assess which of these in vitro findings are reproducible in vivo in recipients of stem cell transplants (SCT), since in these patients long- lasting impairments in cytokine inducibility have been described. We have therefore studied the kinetics of putative modulators and mediators of IL-2-induced immune activation, namely IL-1beta, IL-4, IL-5, IL-10, IL-12, soluble Fas ligand (sFasL), and GM-CSF during IL-2 therapy. All patients were children or adolescents suffering from solid tumors with poor prognosis who received three 5-day courses of high-dose intravenous IL-2 as an adjuvant to their radio-chemotherapy and autologous SCT. While IL-1beta, IL-4 and IL-12 were not, and sFasL was only mildly affected by the IL-2 therapy, we observed a consistent and early rise of IL-10, IL-5, and GM-CSF. These increases were rapidly reversible after discontinuation of IL-2 therapy. The inducibility of IL-10, IL-5 and GM-CSF was more pronounced with increasing time from the SCT, and in the third cycle reached an order of magnitude as in high-dose IL-2 patients without SCT. Together with the abundant in vitro data, these findings may help devise a combination immunotherapy permitting stronger anti-tumor effects, but lesser adverse effects.
Collapse
|
165
|
Abstract
Imaging algorithms in congenital heart disease, as in the patient with acquired heart diseases continue to evolve, with more and more information gleaned noninvasively. The emphasis will be on the newer aspects of imaging, not cross sectional echocardiography with color Doppler.
Collapse
|
166
|
Ryu YS, Lee JH, Seok JH, Hong JH, Lee YS, Lim JH, Kim YM, Hur GM. Acetaminophen inhibits iNOS gene expression in RAW 264.7 macrophages: differential regulation of NF-kappaB by acetaminophen and salicylates. Biochem Biophys Res Commun 2000; 272:758-64. [PMID: 10860828 DOI: 10.1006/bbrc.2000.2863] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Acetaminophen is a widely used analgesic and anti-inflammatory drug that is considered a good alternative to salicylates for individuals who cannot tolerate salicylates. Nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation. Recent evidence suggests that anti-inflammatory effect of salicylates lies in the inhibition of iNOS, but nothing has been reported about the direct effect of iNOS expression by acetaminophen. The present study was designed to elucidate sequentially the action mechanisms of acetaminophen and salicylates (aspirin and sodium salicylate) on lipopolysaccharide (LPS) plus interferon-gamma (IFN-gamma)-induced iNOS expression in RAW 264.7 macrophages. Both acetaminophen and salicylates inhibited NO production and iNOS protein expression in a dose dependent manner. Acetaminophen inhibited iNOS mRNA expression, promoter activity of iNOS gene and nuclear factor-kappa B (NF-kappaB) binding activity induced by LPS plus IFN-gamma, whereas salicylates did not show any effect on them. In addition, salicylates did not affect on iNOS mRNA stability induced by LPS plus IFN-gamma. Furthermore, the inhibition of iNOS protein expression and NO production by salicylates was disappeared when salicylates were added for only 5 h to inhibit the early event of iNOS expression. Aspirin also dose dependently inhibited iNOS enzyme activity in cell-free extracts, whereas no significant differences were observed in extracts treated with sodium salicylate or acetaminophen. These findings suggest that acetaminophen may exert analgesic or anti-inflammatory effect by inhibiting iNOS expression induced by LPS plus IFN-gamma at transcriptional level by suppression of NF-kappaB binding activity, whereas salicylates exert its effect by inhibiting iNOS expression at the translational or posttranslational level.
Collapse
|
167
|
Cho D, Song H, Kim YM, Houh D, Hur DY, Park H, Yoon D, Pyun KH, Lee WJ, Kurimoto M, Kim YB, Kim YS, Choi I. Endogenous interleukin-18 modulates immune escape of murine melanoma cells by regulating the expression of Fas ligand and reactive oxygen intermediates. Cancer Res 2000; 60:2703-9. [PMID: 10825144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
It has been known that melanoma cells can suppress the immune system by the Fas ligand. The present study investigated whether interleukin (IL)-18, which can enhance Fas ligand expression, is produced by B16F10 melanoma cells and is involved in immune escape of tumor cells. Immunohistology, reverse transcription-PCR, intracellular fluorescence-activated cell-sorting analysis, and immunoblotting demonstrated that melanoma cells express IL-18. C57BL/6 splenocytes cultured with culture supernatants of B16F10 melanoma cells enhanced IFN-gamma production, which was blocked by anti-IL-18 antibody, indicating that IL-18 in the culture supernatants is functional. In addition to IL-18, the IL-18 receptor was also detected in B16F10 melanoma cells, suggesting a role of this cytokine in regulating the functions of B16F10 melanoma cells. The functional effect of IL-18 on B16F10 melanoma cells was shown by reduction of Fas ligand expression in cells treated with anti-IL-18 antibody or transfected with IL-18 antisense cDNA. In addition, the same treatments decreased intracellular reactive oxygen intermediate levels in B16F10 melanoma cells, indicating that IL-18 regulates reactive oxygen intermediate production, which is involved in Fas ligand expression. Furthermore, transfection of IL-18 antisense cDNA into melanoma cells increased the susceptibility of tumor cells to natural killer cells in vitro. When IL-18 antisense transfectants were implanted into syngeneic mice, severe reduction of tumor cell growth was observed with concomitant infiltrated natural killer cells in the tumor area. Taken together, these results demonstrate that IL-18 has a critical role as a survival factor for B16F10 melanoma cells.
Collapse
|
168
|
Jung YJ, Lee JS, Kim YM. Synthesis and in vitro/in vivo evaluation of 5-aminosalicyl-glycine as a colon-specific prodrug of 5-aminosalicylic acid. J Pharm Sci 2000; 89:594-602. [PMID: 10756325 DOI: 10.1002/(sici)1520-6017(200005)89:5<594::aid-jps5>3.0.co;2-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A simple synthetic route for the preparation of amino acid conjugate of 5-aminosalicylic acid (5-ASA) was exploited and prepared 5-aminosalicyl-glycine (5-ASA-Gly) in good yield. In vitro and in vivo properties of 5-ASA-Gly as a colon-specific prodrug of 5-ASA were investigated using rats as the test animal. Incubation of 5-ASA-Gly with cecal or colonic contents at 37 degrees C released 5-ASA in 65 or 27% of the dose in 8 h, respectively. No 5-ASA was detected from the incubation of 5-ASA-Gly with the homogenates of stomach or small intestine. Plasma concentration of 5-ASA-Gly decreased rapidly after intravenous administration of 5-ASA-Gly, and no 5-ASA was detected in the blood, which indicated 5-ASA-Gly was not degraded in the plasma. After oral administration of 5-ASA-Gly, about 50% of the administered dose was recovered as 5-ASA and N-acetyl-ASA and 3% as 5-ASA-Gly from feces and 14% as 5-ASA-Gly and 28% as 5-ASA and N-acetyl-ASA from urine in 24 h. These results suggested that a large fraction of 5-ASA-Gly was delivered to the large intestine and activated to liberate 5-ASA. For comparison, total recovery of 5-ASA and N-acetyl-5-ASA from feces after oral administration of 5-ASA-Gly was greater than that from sulfasalazine, which is one of the most commonly prescribed prodrugs of 5-ASA.
Collapse
|
169
|
Kim YM, Chung HT, Simmons RL, Billiar TR. Cellular non-heme iron content is a determinant of nitric oxide-mediated apoptosis, necrosis, and caspase inhibition. J Biol Chem 2000; 275:10954-61. [PMID: 10753895 DOI: 10.1074/jbc.275.15.10954] [Citation(s) in RCA: 170] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In this report, we tested the hypothesis that cellular content of non-heme iron determined whether cytotoxic levels of nitric oxide (NO) resulted in apoptosis versus necrosis. The consequences of NO exposure on cell viability were tested in RAW264.7 cells (a cell type with low non-heme iron levels) and hepatocytes (cells with high non-heme iron content). Whereas micromolar concentrations of the NO donor S-nitroso-N-acetyl-DL-penicillamine induced apoptosis in RAW264.7 cells, millimolar concentrations were required to induce necrosis in hepatocytes. Caspase-3 activation and cytochrome c release were evident in RAW264.7 cells, but only cytochrome c release was detectable in hepatocytes following high dose S-nitroso-N-acetyl-DL-penicillamine exposure. Pretreating RAW264.7 cells with FeSO(4) increased intracellular non-heme iron to levels similar to those measured in hepatocytes and delayed NO-induced cell death, which then occurred in the absence of caspase-3 activation. Iron loading was also associated with the formation of intracellular dinitrosyl-iron complexes (DNIC) upon NO exposure. Cytosolic preparations containing DNIC as well as pure preparations of DNIC suppressed caspase activity. These data suggest that non-heme iron content is a key factor in determining the consequence of NO on cell viability by regulating the chemical fate of NO.
Collapse
|
170
|
Kim H, Lee MJ, Kim MR, Chung IP, Kim YM, Lee JY, Jang JJ. Expression of cyclin D1, cyclin E, cdk4 and loss of heterozygosity of 8p, 13q, 17p in hepatocellular carcinoma: comparison study of childhood and adult hepatocellular carcinoma. LIVER 2000; 20:173-8. [PMID: 10847487 DOI: 10.1034/j.1600-0676.2000.020002173.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
AIMS/BACKGROUND In hepatitis B virus-related hepatocellular carcinoma (HCC), at least 20-40 years of continuous necro-inflammation is necessary for the hepato-carcinogenesis to occur. However, HCC in childhood shows an unusually short latent period and rapid progression. In our previous report, mutation of c-met was found only in childhood HCC, but not in adult HCC. In order to determine the specific biological tumorous features of childhood HCC, a comparison study of childhood and adult HCC was performed. METHODS Eighteen cases of HBV positive HCC (nine children and nine adults aged more than 40 years) were selected. The expression of G1 phase regulatory proteins (cyclin D1, cyclin E and cdk4) was studied using immunohistochemical methods. Loss of heterozygosity (LOH) on chromosomal arms 8p, 13q and 17p was analyzed. RESULTS Cyclin D1 expression was significantly lower in childhood HCC than in adult HCC (cases of cyclin D1 expression under 3+: childhood 5/9 vs. adult 1/9, p=0.046). No difference in cyclin E and cdk4 expression was found between childhood and adult HCC. LOH frequency on 13q was relatively higher in childhood than in adult HCC (66.7% vs. 22.2%, p=0.058). LOH frequency on 8p and 17p was 44.4% and 33.3% in childhood HCC and 44.4% and 75% in adult HCC with no statistical significance between the two groups. CONCLUSION Our data suggest that childhood HCC may be less dependent on cyclin D1 protein for tumor growth and progression than adult HCC, and that the LOH on 13q may be an important feature of childhood HCC.
Collapse
MESH Headings
- Adolescent
- Adult
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/pathology
- Carcinoma, Hepatocellular/virology
- Cell Cycle Proteins/metabolism
- Child
- Chromosomes, Human/genetics
- Chromosomes, Human, Pair 13/genetics
- Chromosomes, Human, Pair 17/genetics
- Chromosomes, Human, Pair 8/genetics
- Cyclin D1/metabolism
- Cyclin E/metabolism
- Cyclin-Dependent Kinase 4
- Cyclin-Dependent Kinases/metabolism
- DNA, Neoplasm/analysis
- Fluorescent Antibody Technique, Indirect
- Hepatitis B virus/isolation & purification
- Humans
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/pathology
- Liver Neoplasms/virology
- Loss of Heterozygosity
- Middle Aged
- Polymerase Chain Reaction
- Proto-Oncogene Proteins
Collapse
|
171
|
Kim YM, Lee KK, Oh HS, Park SK, Won JH, Hong DS, Park HS, Park JS, Lee DW. Myelomatous effusion with poor response to chemotherapy. J Korean Med Sci 2000; 15:243-6. [PMID: 10803706 PMCID: PMC3054621 DOI: 10.3346/jkms.2000.15.2.243] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
While pleural effusion in multiple myeloma is relatively infrequent, myelomatous pleural effusion is extremely rare. We experienced a 61-year-old woman with IgD-lambda multiple myeloma and pleural effusion. The diagnosis was made originally by pleural biopsy, pleural fluid cytology and immunoelectropheresis of pleural fluid. Transient improvement of the pleural effusion was observed after administration of combination chemotherapy of vincristine, melphalan, cyclophosphamide, prednisone (VMCP)/vincristine, cyclophosphamide, adriamycin, prednisone (VCAP). Two months later, myelomatous pleural effusion recurred and no response to salvage therapy was observed. We reviewed the clinical feature of this case and literature concerning myelomatous pleural effusion.
Collapse
|
172
|
Kim JW, Cho EH, Kim YM, Kim JM, Han JY, Park SY. Detection of cryptic Y chromosome mosaicism by coamplification PCR with archived cytogenetic slides of suspected Turner syndrome. Exp Mol Med 2000; 32:38-41. [PMID: 10762060 DOI: 10.1038/emm.2000.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Turner syndrome is one of the most common cytogenetic abnormalities. It is known that the Y chromosome or Y derived material is present in 6-9% of TS patient and it may develop a high risk of gonadoblastoma in 15-25%. So it is crucial to carry out cyto genetic analysis and Y-specific probe studies for all persons with gonadal dysgenesis to rule out mosaicism with Y-bearing cell line; eg 45,X/46,XY. In this study, 26 archival slides previously analyzed cytogenetically as 45,X, 45,X/46,X,i(X), 45,X/46,X,r(X), and 45,X/46,XX were examined. Coamplification PCR, having the advantage of providing rapid result and confirming PCR failure, was performed with the slide samples in the regions of dystrophin gene in Xp21and DYZ3 in the Y centromeric region. All of archived slides were positive for X-specific gene and one slide of 45,X was found to have the cryptic Y chromosome material. Our result suggests that the archived cytogenetic slides could be applied for the detection of Y chromosome rapidly and efficiently in TS patients.
Collapse
|
173
|
Pae HO, Kim HG, Paik YS, Paik SG, Kim YM, Oh GS, Chung HT. Nitric oxide protects murine embryonic liver cells (BNL CL.2) from cytotoxicity induced by glucose deprivation. PHARMACOLOGY & TOXICOLOGY 2000; 86:140-4. [PMID: 10752673 DOI: 10.1034/j.1600-0773.2000.d01-26.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We investigated the protective effects of nitric oxide on cell death of murine embryonic liver cells (BNL CL.2) after glucose deprivation. Endogenous nitric oxide production by BNL CL.2 cells was induced by 6 hr pretreatment with interferon-gamma and lipopolysaccharide. We used sodium nitroprusside and S-nitroso-L-glutathione as exogenous nitric oxide-generating compounds. All agents were used at doses that did not show direct cytotoxicity as measured by crystal violet staining assay. In the BNL CL.2 cells, the viability dropped very steeply after 24 hr incubation with glucose-free media. Endogenous nitric oxide produced by treatment of the cells with interferon-gamma and lipopolysaccharide protected the cells from glucose deprivation-induced cytotoxicity, but did not protect them in the presence of the nitric oxide synthesis inhibitor, N(G)-monomethyl-L-arginine. Exogenous nitric oxide protected the cells from glucose deprivation-induced cytotoxicity in a concentration-dependent manner. Cytoprotection by nitric oxide donors was abolished by the use of nitric oxide scavenger, 2-phenyl-4,4,5,5,-tetramethylimidazole, but not by the soluble guanosine cyclase inhibitor, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one. In addition, cytoprotective effects comparable to endogenous or exogenous nitric oxide were not observed when the cells were incubated with dibutyl guanosine 3',5'-cyclic monophosphate. Based upon these results, we suggest that nitric oxide may enhance the cell survival of BNL CL.2 cells after glucose deprivation via a guanosine 3',5'-cyclic monophosphate-independent pathway.
Collapse
|
174
|
Lee OH, Lee DJ, Kim YM, Kim YS, Kwon HJ, Kim KW, Kwon YG. Sphingosine 1-phosphate stimulates tyrosine phosphorylation of focal adhesion kinase and chemotactic motility of endothelial cells via the G(i) protein-linked phospholipase C pathway. Biochem Biophys Res Commun 2000; 268:47-53. [PMID: 10652210 DOI: 10.1006/bbrc.2000.2087] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously shown that sphingosine 1-phosphate (S1P) stimulates motility of human umbilical vein endothelial cells (HUVECs) (O.-H. Lee et al., Biochem. Biophys. Res. Commun. 264, 743-750, 1999). To investigate the molecular mechanisms by which S1P stimulates HUVEC motility, we examined tyrosine phosphorylation of p125 focal adhesion kinase (p125(FAK)) which is important for cell migration. S1P induces a rapid increase in tyrosine phosphorylation of p125(FAK). Compared with other structurally related lipid metabolites such as sphingosine, C2-ceramide, and lysophosphatidic acid, S1P uniquely stimulated p125(FAK) tyrosine phosphorylation and migration of HUVECs. The effect of S1P on p125(FAK) tyrosine phosphorylation was markedly reduced by treatment with pertussis toxin or U73122, a phospholipase C (PLC) inhibitor. As a downstream signal of PLC, p125(FAK) tyrosine phosphorylation in response to S1P was totally blocked by depletion of the intracellular calcium pool. However, protein kinase C (PKC) inhibitor had no effect on the response to S1P. Finally, chemotaxis assays revealed that inhibition of PLC but not PKC significantly abrogated S1P-stimulated HUVEC migration. These results suggest that the G(i)-coupled receptor-mediated PLC-Ca(2+) signaling pathway may be importantly involved in S1P-stimulated focal adhesion formation and migration of endothelial cells.
Collapse
|
175
|
Choi BM, Park R, Pae HO, Yoo JC, Kim YC, Jun CD, Jung BH, Oh GS, So HS, Kim YM, Chung HT. Cyclic adenosine monophosphate inhibits ursolic acid-induced apoptosis via activation of protein kinase A in human leukaemic HL-60 cells. PHARMACOLOGY & TOXICOLOGY 2000; 86:53-8. [PMID: 10728914 DOI: 10.1034/j.1600-0773.2000.d01-10.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This study was designed to investigate the effect of cAMP on ursolic acid-induced apoptosis of HL-60 cells. Ursolic acid decreased the viability of the cells in a dose-dependent manner, which was revealed as an apototic process characterized by ladder-pattern DNA fragmentation in agarose gel electrophoresis and segmented nuclei in DAPI-sulpharhodamin 101 staining. Ursolic acid-induced apoptosis of the cells was markedly inhibited by the addition of cAMP-elevating agents including DB-cAMP, CPT-cAMP, 8-Br-cAMP and forskolin. These results were further evidenced by the fact that inhibitors of cAMP-dependent protein kinase including H89 and KT5720 completely inhibited the cAMP-mediated rescue of HL-60 cells from ursolic acid-induced apoptosis. In addition, differentiating agents of the cells such as dimethyl sulfoxide and retinoic acid did not affect the ursolic acid-induced apoptosis of HL-60 cells. These results suggest that signaling pathway of cAMP-dependent activation of protein kinase A may affect the responsiveness of tumor cells upon ursolic acid.
Collapse
|