Transcriptional Regulation of the Estrogen Receptor alpha Gene by Testosterone in Cultures of Primary Rat Sertoli Cells / 대한내분비학회지

BACKGROUND: We wanted to identify the presence of the estrogen receptor (ER) alpha in Sertoli cells and gain insight on the regulation of the ER alpha gene expression by testosterone in Sertoli cells. The transcriptional regulation of the ER alpha gene was investigated in primary Sertoli cell cultures by in situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR). METHODS: Primary Sertoli cell culture was performed. The expression levels of ER alpha and ER beta mRNA in Sertoli cells were detected by Northern blot, RT-PCR, immunocytochemistry and in situ hybridization. RESULTS: The ovary, testis and epididymis showed a moderate to high expression of ER alpha while the prostate, ovary and LNCap cells showed the ER beta expression. ER alpha mRNA and protein were detected in the germ cells and Sertoli cells by in situ hybridization and immunocytochemistry. The level of ER alpha mRNA was gradually decreased in a time-dependent manner after testosterone treatment, and the changes of ER alpha mRNA were dependent on the concentration of testosterone. Androgen binding protein and testosterone-repressive prostate message-2 (TRPM-2) mRNA were reduced at 24 hour by estradiol, while the transferrin mRNA was not affected. ER alpha mRNA was strongly detectable in the testes of 7 days-old-rats, but it was gradually decreased from 14 to 21 days of age. The primary Sertoli cells also showed the same pattern. The ER alpha gene expression was also regulated by testosterone in the Sertoli cells prepared from the 14- and 21-day old rats. CONCLUSIONS: These results suggest that ER alpha is transcriptionally regulated by testosterone and it may play some role in the Sertoli cells.

Mechanism of Castration-induced Apoptosis of Ventral Prostate in Rat / 대한내분비학회지

BACKGROUNDS: Castration-induced androgen deprivation triggers a sequence of events, which activates apoptotic cell death of the androgen-dependent epithelial cells within the rat ventral prostate. To investigate the mechanism of castration-dependent apoptosis in the rat ventral prostate, the regulation of apoptosis-related genes was been investigated. METHODS: Azaline B was subcutaneously injected into Sprague-Dawley rat. The Fas receptor (Fas), Fas ligand (FasL) and bcl-2 mRNA, as well as the protein levels were detected by RT-PCR and Western blot analyses. Azaline B-dependent apoptosis was determined using TUNEL and a DNA fragmentation assay. The transacting factor of the FasL promoter was identified by DNA footprinting and a DNA mobility shift assay. RESULTS: The rat prostate was regressed after castration, with and the involuted ventral prostate regenerated by testosterone pretreatment, but not by that with FSH. Apoptosis of the ventral prostate was detected, after castration, using toluidine blue staining, a TUNEL assay and an apoptotic DNA fragmentation assay. The levels of Fas, FasL mRNA and protein were increased after castration. In the DNase I footprinting assay, using the FasL promoter and a nuclear extract prepared from a control prostate, at least two sites were protected: the SP-1 binding site at -283 bp and the prostate-unidentified factor(P-UF) binding site at -247 bp. The SP-1 binding activity vanished in the nuclear extract prepared from castrated rats. In the DNA mobility shift assay, the SP-1 binding activity was slightly decreased after castration. Both the Bcl-2 mRNA and Bcl-2 protein were downregulated after castration. CONCLUSION: These results suggest that the Fas/FasL system and Bcl-2 may be important to castrationdependent apoptosis in the rat ventral prostate, with SP-1 related to the castration-dependent regulation of the FasL gene

Mechanism of Castration-induced Apoptosis of Ventral Prostate in Rat / 대한내분비학회지

BACKGROUNDS: Castration-induced androgen deprivation triggers a sequence of events, which activates apoptotic cell death of the androgen-dependent epithelial cells within the rat ventral prostate. To investigate the mechanism of castration-dependent apoptosis in the rat ventral prostate, the regulation of apoptosis-related genes was been investigated. METHODS: Azaline B was subcutaneously injected into Sprague-Dawley rat. The Fas receptor (Fas), Fas ligand (FasL) and bcl-2 mRNA, as well as the protein levels were detected by RT-PCR and Western blot analyses. Azaline B-dependent apoptosis was determined using TUNEL and a DNA fragmentation assay. The transacting factor of the FasL promoter was identified by DNA footprinting and a DNA mobility shift assay. RESULTS: The rat prostate was regressed after castration, with and the involuted ventral prostate regenerated by testosterone pretreatment, but not by that with FSH. Apoptosis of the ventral prostate was detected, after castration, using toluidine blue staining, a TUNEL assay and an apoptotic DNA fragmentation assay. The levels of Fas, FasL mRNA and protein were increased after castration. In the DNase I footprinting assay, using the FasL promoter and a nuclear extract prepared from a control prostate, at least two sites were protected: the SP-1 binding site at -283 bp and the prostate-unidentified factor(P-UF) binding site at -247 bp. The SP-1 binding activity vanished in the nuclear extract prepared from castrated rats. In the DNA mobility shift assay, the SP-1 binding activity was slightly decreased after castration. Both the Bcl-2 mRNA and Bcl-2 protein were downregulated after castration. CONCLUSION: These results suggest that the Fas/FasL system and Bcl-2 may be important to castrationdependent apoptosis in the rat ventral prostate, with SP-1 related to the castration-dependent regulation of the FasL gene

Mechanism of Azaline B-induced Apoptosis in Rat Testis / 대한비뇨기과학회지

PURPOSE: To identify the mechanism of azaline B-dependent apoptosis, the regulation of Fas and FasL genes has been investigated. MATERIALS AND METHODS: Azaline B was subcutaneously injected into Sprague-Dawley rats. The levels of Fas receptor (Fas) and Fas ligand (FasL) were detected by reverse transcription-polymerase chain reaction (RT- PCR). Azaline B-dependent apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling (TUNEL) and DNA fragmentation assay. Transacting factor of FasL promoter was identified by DNase I footprinting and DNA mobility shift assay. RESULTS: The azaline B-treated testis (250microgram/kg body wt/day) had decreased to 70+/-2.5% and 38+/-1.8% of the normal testis weight at 3 and 5 days after the injection, respectively, but the weights of the testis were not changed after pretreatment of follicle-stimulating hormone (FSH) and testosterone. Apoptosis of the testis was detected by DNA fragmentation assay and TUNEL assay after the azaline B treatment. The levels of Fas and FasL mRNA were increased by the treatment of azaline B in both time- and dose-dependent manners. In DNase I footprinting assay with FasL promoter, the nuclear factor prepared from control was bound with at least four sites: SP-1 binding site at 283, NF-kappa B binding site at 219, TATA at 132 and the gamma-interferon response element (gamma-IRE) at 78. gamma-IRE was completely protected by the nuclear extract prepared from azaline B-treated rat testis. In DNA mobility shift assay, the binding activity of gamma-IRE binding protein was increased after azaline B treatment. CONCLUSIONS: These results suggest that Fas-FasL system may be important to azaline B-dependent apoptosis in rat testis and that gamma-IRE binding protein is related to the azaline B-dependent regulation of FasL gene.

Specialized Functions and Hormonal Regulation of Sertoli Cell / 대한내분비학회지

No abstract available.

Activation of epidermal growth factor receptor is responsible for pervanadate-induced phospholipase D activation

Pervanadate, a complex of vanadate and H2O2, has an insulin mimetic effect, and acts as an inhibitor of protein tyrosine phosphatase. Pervanadate-induced phospholipase D (PLD) activation is known to be dependent on the tyrosine phosphorylation of cellular proteins and protein kinase C (PKC) activation, and yet underlying molecular mechanisms are not clearly understood. Here, we investigated the signaling pathway of pervanadate-induced PLD activation in Rat2 fibroblasts. Pervanadate increased PLD activity in dose- and time- dependent manner. Protein tyrosine kinase inhibitor, genistein, blocked PLD activation. Interestingly, AG-1478, a specific inhibitor of the tyrosine kinase activity of epidermal growth factor receptor (EGFR) blocked not only the PLD activation completely but also phosphorylation of p38 mitogen- activated protein kinase (MAPK). However, AG-1295, an inhibitor specific for the tyrosine kinase activity of pletlet drived growth factor receptor (PDGFR) did not show any effect on the PLD activation by pervanadate. We further found that pervanadate increased phosphorylation levels of p38, extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK). SB203580, a p38 MAPK inhibitor, blocked the PLD activation completely. However, the inhibitions of ERK by the treatment of PD98059 or of JNK by the overexpression of JNK interacting peptide JBD did not show any effect on pervanadate-induced PLD activation. Inhibition or down-regulation of PKC did not alter the pervanadate-induced PLD activation in Rat2 cells. Thus, these results suggest that pervanadate-induced PLD activation is coupled to the transactivation of EGFR by pervanadate resulting in the activation of p38 MAP kinase.

Mechanism of Azaline B-induced Apoptosis of Ventral Prostate in Rat / 대한비뇨기과학회지

PURPOSE: Androgen deprivation triggers a sequence of events that activates apoptotic cell death of the androgen-dependent epithelial cells within the rat ventral prostate, ultimately resulting in the involution of the gland. To investigate the mechanism of azaline B-dependent apoptosis in the rat ventral prostate, the regulation of apoptosis-related genes were examined. MATERIALS AND METHODS: Azaline B was subcutaneously injected in Sprague-Dawley rat. Fas receptor(Fas), Fas ligand(FasL), bcl-2 mRNA, and protein levels were detected by RT-PCR and Western blot. Azaline B-dependent apoptosis was determined by TUNEL and DNA fragmentation assay. Transacting factor of FasL promoter was identified by DNA footprinting and DNA mobility shift assay. RESULTS: The prostate regressed after azaline B treatment in rat, and the involuted ventral prostate regenerated after testosterone pretreatment. Apoptosis of the ventral prostate was detected by TUNEL assay and apoptotic DNA fragmentation assay after azaline B treatment. The levels of Fas and FasL mRNA and protein increased after azaline B treatment. In DNase I footprinting assay with FasL promoter using nuclear extract prepared from control prostate, at least two sites were protected: SP-1 binding site at -283bp and prostate-unidentified factor(P-UF) binding site at -247bp. SP-1 binding activity vanished in the nuclear extract prepared from azaline B-treated rats. In the DNA mobility shift assay, SP-1 binding activity decreased after azaline B treatment. Bcl-2 mRNA and protein were downregulated after azaline B treatment. CONCLUSIONS: These results suggest that Fas/FasL system and Bcl-2 are important to azaline B-dependent apoptosis in rat ventral prostate and that SP-1 is related to azaline B-dependent regulation of the FasL gene.

Epidermal Growth Factor Dependent Expression of Plasminogen Activator and Plasminogen Activator Inhibitor in Rat Hepatocytes in Primary Culture

PURPOSE: In order to clarify the the role of epidermal growth factor (EGF) in the regulation of plasminogen activator (PA) and plasminogen activator inhibitor (PAI) during liver regeneration, we investigated the EGF-dependent gene expression of PA and PAI-1 in rat hepatocytes in primary culture. METHODS: Hepatocytes were isolated from rats using a two step perfusion technique and cultivated in dishes precoated with rat tail collagen. DNA synthesis of the hepatocytes by EGF treatment was measured with (3)H-thymidine incorporation. Gene expression for PAI-1, uPA and tPA was examined using Northern blot hybridization analysis. RESULTS: EGF treatment increased the (3)H-thymidine incorporation of the hepatocytes up to 36 hours and normal polygonal hepatocyte morphology was achieved simultaneously. tPA and PAI-1 mRNA were detected in the control hepatocytes. With the EGF treatment, the tPA mRNA level increased with time up to 48 hours, however the PAI-1 mRNA level rapidly increased to 1 hour and then decreased quickly to the control level. On the contrary, uPA mRNA was not detected in hepatocytes with or without treatment of EGF. The EGF-dependent induction of tPA and PAI-1 mRNA was a protein synthesis independent process. CONCLUSION: These results suggest that differential expression of tPA and PAI-1 mRNA by EGF in hepatocytes may play an important role in the regulation of liver regeneration. Among PAs, tPA seemed to be more important in EGF dependent growth or regeneration of primary hepatocytes in the rat since uPA mRNA was not induced in primary hepatocyte cultures in spite of EGF treatment.

Transcriptional Regulation of H2B Histone Gene Expression by Nocodazole in HL-60 Cells / 대한암학회지

PURPOSE: Nocodazole, a microtubule disrupting reagent, is known to arrest cells in the M phase, To gain insight on the regulatory mechanism of H2B histone gene expression by nocodazole in HL-60 cell, the binding pattern of nuclear proteins to cis element in the human H2B histone gene promoter has been investigated with DNase I footprinting and DNA mobility shift assay. MATERIALS AND METHODS: Northern blot hybridization was performed by the method of Virca et al. A Hinc II-Sac I fragment of pSPH28 was used as probe for Northern blot analysis of H2B histone mRNA. DNase I footprinting and DNA mobility shift assay were performed by the method of Lim et al. End labeled DNA oligomer (upper strand, 5'-CTTCACCTTATTTGCATAA GCGATTC-3') for octamer binding activity was mixed with nuclear extracts in a 20 ul reaction volume containing 60 mM KC1, 12 mM HEPES, pH 7.9, 5 mM MgCl2, 0.2 mM EDTA, 0.2 mM DTT, 12% glycerol, and 2 ug of poly [dI-dC]. RESULTS: The level of H2B histone mRNA rapidly was reduced at 24 hours in nocodazole-treated HL-60 cells and the mRNA was repressed in proportion to the concentration of nocodazole. Nocodazole-dependent repression of H2B histone gene was restored by replacement with nocodazole-free media. In DNase I footprinting analysis, one nuclear factor bound at 42 bp site (octamer motif) in the absence of nocodazole. In the presence of nocodazole, the binding of nuclear factor on octamer motif partially vanished. In DNA mobility shift assay, one DNA-protein complex (Octl) was formed when octamer motif was incubated with nuclear extract of HL-60 cell. After nocodazole treatment, Octl binding activity was reduced by time dependent manner. CONCLUSION: These results suggest that nocodazole-dependent repression of H2B histone gene is correlated with reduction of Octl binding activity in HL-60 cell.

Association of castration-dependent early induction of c-myc expression with a cell proliferation of the ventral prostate gland in rat

The protooncogene c-myc is known to be associated with both cell proliferation and apoptosis. The possible cellular affects of castration on the ventral prostate gland of rat as well as the relationship to a castration induced c-myc expression were examined. Levels of c-myc mRNA in the ventral prostate gland peaked at 6 h (early induction) and 48 h (late induction) after castration, respectively. Castration-induced DNA fragmentation was not observed at an early induction of c-myc mRNA. DNA fragmentation appeared to be testosterone-dependent. On the other hand, cellular DNA synthesis measured by [3H]thymidine uptake in the ventral prostate gland was increased to maximum at 6 h after castration. These results suggest that an early induction of c-myc mRNA in ventral prostate gland after castration is closely associated with cell proliferation of the gland.

Role of ATF on Transcriptional Regulation of DNA Topoisomerase II a Gene in HL - 60 Arrested to G2 / M and M Phase / 대한암학회지

PURPOSE: To gain insight on transcriptional repression of Topo II a in HL-60 cells arrested to G2/M and M phase, the levels of Topo IIa mRNA and the binding activity of ATF have been investigated with Northern blot hybridization and DNA mobility shift assay, respectively. MATERIALS AND METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-mactivated fetal bovine serum and antibiotics in a humidified 5% CO2 at 37C degree. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. A Xho I-Mlu I fragment of phTOP2 was used as probe for Northern blot analysis of Topo II a mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA oligomer (upper strand, 5-TCTCCGCTATGACGCCGAGTGGTG-3) for ATF binding activity was mixed with nuclear extracts in a 20 pl reaction volume containing 60 mM KC1, 12 mM HEPES, pH 7.9, 5 mM MgCl2, 0.2 mM EDTA, 0.2 mM DTT, 12% glycerol, and 2 ug of poly [dI-dC]. RESULTS: HL-60 cells were arrested at G2/M phase and M phase after taxol or nocodazole treatment. The levels of Topo II a mRNA were reduced at 24 hours after exposure with nocodazole or taxol but the unknotting activities were not changed. DNA mobility shift assay using oligonucleotide containing the ATF binding site showed that ATF binding activity was reduced after pretreatment of nododazole or taxol. CONCLUSIONS: These results suggest that the reduction of ATF binding activity may be important to transcriptional repression of Topo II a gene by nocodazole and taxol in HL- 60 cells.

Study of Pro-inflammatory Cytokines in Endotoxin Induced Uveitis

Cytokines are produced during the effector phases of natural and specific immunity and serve to mediate and regulate immune and inflammatory responses. In natural immunity,endotoxin directly stimulates mononuclear phagocytes to secrete their cytokines and cytokines which were produced by one cell type often regulate the synthesis of cytokined by other cells. To gain effects on the role of pro-inflammatoy cytokines(TNF, IL-1, IL-6) in the endotoxin induced uveitis, author investigated the cell counts of infilterating inflammatory cells, IL-6 bioassay in aqueous humor, mRNA analysis in the transgenic endotoxin induced uveitic mice(TNF-R(-), IL-1R(-), TNF-R(-)/IL-1R(-)). In this study, there was no significant difference in the number of infiltering cells in TNF-R(-) mice compared to congenic controls, but significant diffetence in the unmber of infiltering cells was found in IL-1R(-) and TNF-R(-)/IL-1R(-) mice. IL-6(-) levels in aqueous humor were reduced in IL-1R(-) and TNF-R(-)/IL-1R(-) mice. TNF-alpha, IL-1alpha, IL-6 mRNA were detected in all experimental mice after endotoxin injection. IL-1alpha and IL-1Ralpha mRNA were detected in noninjected TNR-R(-) mice. IL-1beta mRNA was not detected in all experimental mice without or with endotoxin injection. In conlclusion, IL-1 appears to have a more important role in endotoxin induced uveits than TNF. Though IL-6 is detected in endotoxin induced uveitis, it is not an indicator for the enhenceing inflammation and may not be essential for the endotoxin induced uveitis.

The Effects of NMDA Antagonists and Sympathectomy on the c-Fos mRNA Expression in the Neuropathic Rat / 대한마취과학회지

BACKGROUND: Neuropathic pain produced by nerve injury has the characteristics of enhanced pain responses - allodynia. To understand the pathophysiology of the neuropathic pain, We evaluated the effect of NMDA antagonists and chemical sympathectomy on the c-fos mRNA expression. METHODS: We have divided rats(Sprague-Dawley, N=24) that their left L5 and L6 nerve were tightly ligated into two groups. In NMDA antagonist group(N=17), We injected 10 g MK801 and 10 g 5-amino-phosphonovalerate in three ways, intrathecally before the ligation, after ligation and subcutaneous continuously. Then behavioral tests for mechanical allodynia and cold allodynia were performed. After the test of allodynia,the expression of c-fos were assessed by Northern blot hybridization. In chemical sympathectomy group(N=7), We injected 70 mg/kg guanethidine into the peritoneum in two ways, before the ligation and after ligation. Then same methods were performed in NMDA antagonist group as well. RESULTS: Intrathecal NMDA antagonists before the ligation supressed the elevation of c-fos mRNA expression. Intrathecal NMDA antagonists on the 7 days after the ligation reduced the c-fos mRNA expression and neuropathic pain. Continuous treatment of subcutaneous NMDA antagonists supressed the development of neuropathic pain and the elevation of c-fos mRNA expression. Chemical sympathectomy before the ligation did not supress the elevation of c-fos mRNA expression. Chemical sympathectomy on the 7 days after the ligation reduced neuropathic pain and the elevation of c-fos mRNA expression. CONCLUSIONS: NMDA receptor is related to the induction and maitenance of neuropatic pain, and sympathetic nervous system has a main role in the already induced neuropathic pain.

Transcriptional REpression of Vimentin Gene During All-TTrans Retinoic Acid-Induced Differentiation of HL-60 Cells / 대한내분비학회지

BACKGROUND: Vimentin is the major intermediate-size filament in the cytoplasm of cells from mesenchymal origin. The HL-60 cell is a unique human leukemic cell line capable of terminal differentiation with several chemical inducers, and then the cell line becomes a fre#quently described model system for cell differentiation in vitro. Vimentin mRNA is reduced during all-trans retinoic acid (retinoic acid) -dependent differentication but increased by 12-0-tetradecanoylphorbol-13-acetate (TPA). In this paper, we have investigated on the mechanism of transcriptional repression of vimentin gene during retinoic acid-dependent differentication of HL-60 cell. METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-inactivated fetal bovine serum and antibiotics in a humidified 5% CO at 37C. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. EcoRI fragment of pVIM-GEM was used as probe for vimentin mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA probe (Upper strand, 5-CGCITGATGAGTCAGCCG-3) for AP-1 binding activity was mixed with nuclear extracts in a 20 pL reaction volume containing 300 mM KCI, 60 mM HEPES, pH 7.9, 25mM MgC1, 1mM EDTA, 1mM DTT, 60% glycerol, and 2 pg of poly[dI-dC]. RESULTS: The level of vimentin mRNA was decreased at 12 hours after retinoic acid treatment, and not detected at 48 hours. The level of vimentin mRNA was reduced in proportion to concentration of retinoic acid, Retinoic acid-reduced vimentin mRNA was no change in cells treated with cycloheximide. Retinoic acid-dependent decrease of vimentin mRNA was partially recovered by staurosporin pretreatment. In DNA mobility shift assay, AP-1 binding activity was reduced at 48 hr during retinoic acid-induced differentiation. CONCLUSION: These results suggest that the transcriptional repression of vimentin gene during retinoic acid-induced differentiation in HL-60 cells is correlated with reduction of DNA binding activity of AP-1.

Role of AP-1 Transcriptional Regulation of Vimentin Gene during 12-O-Tetradecanoylphorbol-13-Acetate Differentiation of HL-60 Cells / 대한암학회지

PURPOSE: To gain insight on the role of AP-1 in transcriptional regulation of vimentin gene during differentiation of HL-60 cells by 12-0-tetradecanoylphorbol-13-acetate (TPA), the levels of vimentin mRNA and AP-1 have been investigated with Northern blot hybridization and DNA mobility shift assay. MATERIALS AND METHODS: HL-60 cells were grown in RPMI 1640 medium supplemented with 10% heat-inactivated fetal calf serum and antibiotics in a humidified 5% CO2 at 37 degree C. Total RNA was prepared by a modification of the method of Karlinsey et al. Northern blot hybridization was performed by the method of Virca et al. EcoRI fragment of pVIM-GEM was used as probe for vimentin mRNA. DNA mobility shift assay was performed by the method of Lim et al. End labeled DNA probe(Upper strand, 5'-CGCTTGATGAGTCAGCCG- 3') for AP-1 binding activity was mixed with nuclear extracts in a 20 microliter reaction volume containing 300 mM KC1, 60 mM HEPES, pH 7.9, 25 mM MgCl2, 1 mM EDTA, 1 mM DTT, 60% glycerol, and 2 microgram of poly[dI-dC]. RESULTS: TPA increased vimentin mRNA levels, with maxima1 stimulation reached at 24 hr. The level of vimentin mRNA was induced in proportion to the concentration of TPA. TPA-induced vimentin mRNA was almost reduced by actinomycin-D pretreatment. TPA- induced stimulation of vimentin gene was completely reduced by staurosporin pretreatment. In DNA mobility shift assay, AP-I newly appeared at 24 hr during TPA- induced differentiation and was almost not detected after the pretreatment of staurosporin. CONCLUSIONS: These results suggest that the induction of vimentin mRNA during TPA- dependent differentiation in HL-60 cells may be mediated by protein kinases C signal transduction and AP-1 is important to transcriptional regulation.

Role of Cell Surface Mucin on Invasion and Metastasis of HM7 Colon Cancer Cells / 대한암학회지

PURPOSE: Mucinous colorectal cancers have a poorer prognosis than which colorectal cancer produce low amount of mucin, but the exact mechanism is not well understood. The present study was undertaken to elucidate the exact mechanism of invasion and metastasis of high mucin producing colon cancer cells using mucin glycosylation inhibitor, benzyl-alpha-N-acetylgalactosamine. MATERIALS AND METHODS: To evaluate the effect of glycosylated mucin on invasion and metastasis, in vitro invasion, metalloproteinases (MMPs) activity, cell-matrix protein binding, cell-cell aggregation, as well as endothelial leukocyte adhesion molecule (ELAM-1) binding and cell surface expression of various mucin related antigens were analyzed. RESULTS: MMPs activity in conditioned medium and invasion of ECM-coated porous filters by benzyl-alpha-GalNAc treated HM7 cells were decreased. There was no difference between control and treated HM7 cells in terms of matrix protein binding assay, but treated HM7 cells showed higher homotypic cell adhesion. The binding activity of treated HM7 cells to ELAM-1 was significantly decreased and fixed cell binding of MoAb SNH-3, 19-9 (specific for sialyl-Lewis X and sialyl-Lewis A) were also significantly decreased. CONCLUSION: These results suggest that glycosylated mucin modulates ELAM-1 binding, MMPs activity and homotypic cell adhesion, therefore enhance invasive and metastatic properties of human colon cancer cells.

The Gene Expression of Dynorphin, Enkephalin, c-Fos in the Neuropathic Rat / 대한마취과학회지

BACKGROUND: We studied the time course of gene expression of dynorphin, enkephalin, c-fos, and the changes of allodynia, and the effect of chemical sympathectomy on the gene expression and allodynia in neuropathic rat. METHODS: In two groups of rat (Sprague-Dawley), the left L5 and L6 spinal nerves were tight ligated. In gene expression group (N=25), behavioral tests for mechanical allodynia and cold allodynia were perfomed for the next two weeks. After the test of allodynia, the expression of dynorphin, enkephalin, c-fos were assessed by Northern blot hybridization. In chemical sympathectomy group (N=16), after chemical sympathectomy (guanethidine 70 mg/kg intraperitoneally, from postoperative 7 days to 9 days), the changes of allodynia and the gene expression of enkephalin, c-fos were tested. RESULTS: Mechanical allodynia and cold allodynia was developed on the postoperative 3, 5, 7, 14 days. Preprodynorphin mRNA expression was reached peak level at the postoperative 8 hrs, sustained increase by the postoperative 3 days, but preproenkephalin mRNA expression increased slightly after operation. c-Fos mRNA expression was increased immediately at the postoperative 30 min, 1 hr, returned to normal level thereafter, and increased again on the postoperative 3, 5, 7 days that neuropathic pain was developed. Mechanical allodynia and cold allodynia were decreased by chemical sympathectomy. The increased c-fos mRNA expression and pain at postoperative 7 days was reduced by chemical sympathectomy. CONCLUSION: These results suggest that the transient gene expression of dynorphin and c-fos after tight ligation of L5 and L6 spinal nerves induces the development neuropathic pain, and late c-fos expression is related to neuropathic pain.

Studies on expression of DNA topoisomerases genes and protooncogene c-Myc during hepatocarcinogenesis / 대한암학회지

No abstract available.