bluuebunny/crossref_metadata_2025_split huggingface dataset:
PKC‐ζ is required for angiotensin II‐induced activation of ERK and synthesis of C‐FOS in MCF‐7 cells
Authors: Muscella Antonella , Greco Simona , Elia Maria Giovanna , Storelli Carlo , Marsigliante Santo 
Published: August 2003

AbstractWe examined the signalling pathways responsible for the Ang II induction of growth in MCF‐7 human breast cancer cells. Ang II in MCF‐7 cells induced: (a) the translocation from the cytosol to membrane and nucleus of atypical protein kinase C‐ζ (PKC‐ζ) but not of PKC‐α, ‐δ, ‐ε and ‐η; (b) the expression of c‐fos mRNA and protein; (c) the phosphorylation of the extracellular signal‐regulated protein kinases 1 and 2 (ERK1/2). All these effects were due to the activation of the Ang II type I receptor (AT1) since they were blocked by the AT1 antagonist losartan. The Ang II‐stimulated ERK1/2 phosphorylation was blocked by (a) high doses of staurosporine, inhibitor of PKC‐ζ, and by a synthetic myristoylated peptide with sequences based on the endogenous PKC‐ζ pseudosubstrate region (ζ‐PS); (b) PD098059, a mitogen‐activated protein kinase kinase inhibitor (MAPKK/MEK); and, moreover, (c) the inhibitors of phosphoinositide 3‐kinases (PI3K), LY294002 and wortmannin, thus indicating that PI3K may act upstream of ERK1/2. The Ang II‐evoked c‐fos induction was blocked only by high doses of staurosporine and by ζ‐PS whilst PD098059, LY294002 and wortmannin were ineffective, thus indicating that c‐fos induction is not due to ERK1/2 activity. When the epidermal growth factor‐receptor (EGFR) tyrosine kinase activity was inhibited by the use of its inhibitor AG1478, Ang II was still able to induce ERK1/2 phosphorylation and c‐fos expression, therefore proving that the transactivation of EGFR was not required for these Ang II effects in MCF‐7 cells. The previously reported proliferation of MCF‐7 cells induced by Ang II was blocked by PD098059 and by wortmannin in a dose‐dependent manner, thereby indicating that in MCF‐7 cells the PI3K and ERK pathways mediate the mitogenic signalling of AT1. Our results suggest that in MCF‐7 cells Ang II activates multiple signalling pathways involving PKC‐ζ, PI3K and MAPK; of these pathways only PKC‐ζ appears responsible for the induction of c‐fos. J. Cell. Physiol. 197: 61–68, 2003© 2003 Wiley‐Liss, Inc.
Kaempferol‐induced growth inhibition and apoptosis in A549 lung cancer cells is mediated by activation of MEK‐MAPK
Authors: Nguyen T.T.T. , Tran E. , Ong C.K. , Lee S.K. , Do P.T. , Huynh T.T. , Nguyen T.H. , Lee J.J. , Tan Y. , Ong C.S. , Huynh H. 
Published: August 2003

AbstractA vast variety of naturally occurring substances have been shown to protect against experimental carcinogenesis and an increasing amount of evidence suggests that kaempferol may have cancer chemopreventative properties. However, the precise underlying protective mechanisms are poorly understood. To elucidate these mechanisms, we challenged human lung cancer cell line A549 with kaempferol and investigated its effects upon cellular growth and signal transduction pathways. Treatment of A549 cells with kaempferol resulted in a dose‐ and time‐dependent reduction in cell viability and DNA synthesis with the rate of apoptosis equivalent to 0.9 ± 0.5, 5.2 ± 1.5, 16.8 ± 2.0, 25.4 ± 2.6, and 37.8 ± 4.5% on treatment with 0, 17.5, 35.0, 52.5, and 70.0 μM kaempferol, respectively. Concomitantly, kaempferol treatments led to a 1.2‐, 2.7‐, 3.3‐, and 3.4‐fold increase in Bax. Similar elevations were also observed in Bad which increased 1.2‐, 3.3‐, 3.7‐, and 4.7‐fold, respectively, as compared to control. Bcl‐2 and Bcl‐xL expression were inhibited in a dose‐dependent fashion. While the Akt‐1 and phosphorylated Akt‐1 were inhibited, the mitogen‐activated protein kinase (MAPK) was activated upon kaempferol treatment. Kaempferol induced apoptosis was associated with the cleavage of caspase‐7 and poly ADP‐ribose polymerase (PARP). Inhibition of MEK1/2 but not PI‐3 kinase blocked kaempferol‐induced cleavage of caspase‐7, PARP cleavage, and apoptosis. The results suggest that inactivation of Akt‐1 and alteration of Bcl‐2 family of proteins are not sufficient for kaempferol to induce apoptosis and activation of MEK‐MAPK is a requirement for kaempferol‐induced cell death machinery in A549 cells. J. Cell. Physiol. 197: 110–121, 2003© 2003 Wiley‐Liss, Inc.
Downregulation of a rheumatoid arthritis‐related antigen (RA‐A47) by ra‐a47 antisense oligonucleotides induces inflammatory factors in chondrocytes
Authors: Hattori Takako , Kawaki Harumi , Kubota Satoshi , Yutani Yasutaka , Crombrugghe Benoit de , Mark Klaus von der , Takigawa Masaharu 
Published: August 2003

AbstractPreviously we have shown that the expression of RA‐A47 (rheumatoid arthritis‐related antigen) which is identical to HSP47, a collagen‐binding chaperon, is downregulated in chondrocytes by tumor necrosis factor α (TNFα). RA‐A47 was also found on the surface of chondrocytes where it is recognized as an antigen in the serum of rheumatoid arthritis (RA) patients. Its translocation to the cell surface from endoplasmic reticulum membrane where it is normally located was also enhanced by TNFα. To understand the significance of RA‐A47 downregulation in chondrocytes independent from other effects of TNFα, we used an antisense oligonucleotide approach and investigated the effect of this treatment on the expression of molecules related to matrix degradation and production of growth factors for chondrocytic, endothelial, and synovial cells. Here we show that treatment of rabbit chondrocyes and human chondrosarcoma cells HCS‐2/8 by ra‐a47 antisense S‐oligonucleotides significantly reduced the expression of ra‐a47 both at mRNA and protein level. Interestingly, this TNFα‐independent RA‐A47 downregulation was associated with a strong induction of matrix metalloproteinase (MMP)‐9 mRNA and inducible NO synthase (iNOS) mRNA. The induction of active‐type MMP‐9 was further detected by gelatin zymography. Under the same conditions, the release of basic fibroblast growth factor (bFGF) and connective tissue growth factor (CTGF) from HCS‐2/8 cells into the conditioned medium (CM) was strongly enhanced. These effects were not a result of TNFα upregulation, since the ra‐a47 antisense oligonucleotide treatment did not enhance TNFα synthesis. These observations indicate that downregulation of RA‐A47 induces TNFα‐independent cartilage‐degrading pathways involving iNOS and MMP‐9. Furthermore, the stimulation of bFGF and CTGF release from chondrocytes may stimulate the proliferation of adjacent endothelial and/or synovial cells. J. Cell. Physiol. 197: 94–102, 2003© 2003 Wiley‐Liss, Inc.
Phenotypic change regulates monocyte chemoattractant protein‐1 (MCP‐1) gene expression in human retinal pigment epithelial cells
Authors: Uetama Tomoko , Ohno‐Matsui Kyoko , Nakahama Ken‐ichi , Morita Ikuo , Mochizuki Manabu 
Published: August 2003

AbstractWe investigated the expression profile of monocyte chemoattractant protein‐1 (MCP‐1) in human retinal pigment epithelial (RPE) cells under different culture conditions and evaluated the molecular mechanism responsible for MCP‐1 gene expression in RPE cells. After cellular confluence, total RNA was extracted and used for RT‐PCR. Medium conditioned by RPE was used for ELISA and Western blotting. The result showed that RPE cells cultured on plastic expressed MCP‐1 constitutively in the absence of any stimuli. On the other hand, growing human RPE on laminin‐coated flasks instead of plastic reduced the production of MCP‐1. In the RPE cells cultured on plastic, IκB was degraded and A20 protein increased concomitantly. MCP‐1 upregulation in RPE cells on plastic was attenuated by the addition of MG‐132, a proteasome inhibitor. Also, the addition of pyrolidine dithiocarbonate (PDTC) and hypoxic conditions (0.5% O2) decreased MCP‐1 production in these cells. These findings suggested that the expression profile of MCP‐1 is regulated by phenotypic alterations of the RPE cells. And the increased MCP‐1 expression in RPE cells cultured on plastic is caused via spontaneous activation of NFκB induced by susceptibility to oxidative stress. J. Cell. Physiol. 197: 77–85, 2003© 2003 Wiley‐Liss, Inc.
Rat brain pericyte cell lines expressing β2‐adrenergic receptor, angiotensin II receptor type 1A, klotho, and CXCR4 mRNAs despite having endothelial cell markers
Authors: Asashima Tomoko , Iizasa Hisashi , Terasaki Tetsuya , Nakashima Emi 
Published: August 2003

AbstractPericytes are an integral component of blood capillaries, but their involvement in a variety of conditions and diseases, including hypertension and multiple sclerosis, is poorly understood. In order to analyze the mRNA expression of markers related to hypertension and multiple sclerosis in rat brain pericytes, we have established brain capillary pericyte cell lines from temperature‐sensitive SV40 large T antigen transgenic rats. The newly established clones showed similar biochemical and morphological properties to primary pericytes. The expression of endothelial cell‐related markers Flt‐1, Flk‐1, Tie‐1, and Tie‐2 was evaluated by RT‐PCR analysis. β2‐Adrenergic receptor (β2‐AR), angiotensin II receptor type1A (AT1A), and klotho were also evaluated as markers related to hypertension and multiple sclerosis. All of the isolated clones expressed β2‐AR, AT1A and klotho genes. They also stably expressed Flt‐1 and Tie‐2, while Flk‐1, Tie‐1 and CXCR4 were expressed only at low levels in some of the clones. The expressions of AT1 in TR‐PCT1 were determined by Western blotting. Angiotensin II stimulated migration of pericytes. This effect was blocked by an AT1 antagonist. The pericyte cell lines established here are pluripotent, and should be useful for analysis of the reactivity and biological roles of pericytes. J. Cell. Physiol. 197: 69–76, 2003© 2003 Wiley‐Liss, Inc.
IGF‐1 enhances a store‐operated Ca2+ channel in skeletal muscle myoblasts: Involvement of a CD20‐like protein
Authors: Ju Yue‐Kun , Wu Ming‐Jie , Chaulet Herve , Marciniec Tadeusz , Graham Robert M. , Allen David G. 
Published: August 2003

AbstractOverexpression of IGF‐1 in C2C12 myoblasts causes hypertrophy when myoblasts fuse to form myotubes, a response that requires elevated intracellular calcium. We show that myoblasts contain a store‐operated Ca2+ channel (SOCC) whose activity is enhanced with IGF‐1 overexpression. A membrane protein, CD20, can cause Ca2+ entry, which is increased by IGF‐1. We therefore tested whether CD20 mediates the SOCC activity in myoblasts. An antibody to the extracellular loop of CD20 detected a protein in myoblasts and this antibody also inhibited Ca2+ entry through SOCC. Overexpression of CD20 in myoblasts increased SOCC activity. However, we could not detect mRNA for CD20 in myoblasts and an antibody to the intracellular C‐terminus of CD20 was unable to detect CD20 in these cells. These studies demonstrate that CD20 is a novel SOCC or modulates SOCC activity. However, the SOCC activity observed in C2C12 myoblasts is mediated not by CD20, but by a CD20‐like protein. Activation of this SOCC may contribute to IGF‐1‐induced hypertrophy in these cells. J. Cell. Physiol. 197: 53–60, 2003© 2003 Wiley‐Liss, Inc.
Gicerin, an Ig‐superfamily cell adhesion molecule, promotes the invasive and metastatic activities of a mouse fibroblast cell line
Authors: Tsukamoto Yasuhiro , Egawa Michiko , Hiroi Satoshi , Furuya Masaru , Tsuchiya Seiichiro , Sasaki Fumihiko , Miki Naomasa , Taira Eiichi 
Published: August 2003

AbstractGicerin is a cell adhesion molecule in the immunoglobulin (Ig) superfamily and plays an important role during development through its adhesive properties. Gicerin has two isoforms that differ in their cytoplasmic domains; s‐gicerin is the shorter and l‐gicerin the longer form of the protein. Gicerin is over‐expressed in some sporadic tumors as well as in developing tissues. To provide direct evidence that gicerin has the potential to participate in malignant aspects of tumor cell behavior, a gicerin cDNA was introduced into L‐929 cells, an endogenous gicerin‐negative mouse fibroblast and subsequently analyzed for changes in their invasive and metastatic potential by implantation into nude mice and chick embryos. Compared with parental cells, both gicerin isoform transfectants showed an enhanced cell growth and invaded deeply into surrounding tissues from implanted sites in both animal models. Furthermore, l‐gicerin transfectants markedly enhanced metastasis to the lung. These findings suggest that gicerin promotes the tumor growth and invasion, and the isoform bearing the longer cytoplasmic domain may play a role in metastasis. J. Cell. Physiol. 197: 103–109, 2003© 2003 Wiley‐Liss, Inc.
Regulation of the pro‐angiogenic microenvironment by carboxyamido‐triazole
Authors: Oliver Vyta Kulpa , Patton Angela M. , Desai Sudhen , Lorang Dominique , Libutti Steven K. , Kohn Elise C. 
Published: August 2003

AbstractAnti‐angiogenic agents regulate tumor growth by inhibiting endothelial cell proliferation and invasion. Carboxyamido‐triazole (CAI), an inhibitor of non‐voltage‐operated calcium entry and calcium influx‐mediated pathways, has angiogenesis and invasion inhibitory activity. We hypothesized that CAI may express its anti‐angiogenic effects through negative regulation of pro‐angiogenic cytokine production and/or function. In vivo, orally administered CAI prevented A2058 human melanoma xenograft growth and concomitantly resulted in a marked reduction in circulating vascular endothelial growth factor (VEGF) and interleukin‐8 (IL‐8). In vitro, A2058 cell secretion of VEGF was inhibited by CAI treatment under limiting micronutrient conditions that approximate the tumor microenvironment, media restriction, and acidification to pH 6.8 (P = 0.0003 and P = 0.0006, respectively). VEGF and HIF‐1α message and protein were also reduced by CAI treatment. Oral CAI treatment reduced vascular ingrowth in vivo into VEGF‐containing Matrigel plugs. Commensurate with those findings, human umbilical vein endothelial cell (HUVEC) migration towards VEGF was reduced below background by exposure to CAI in the migration chamber (P < 0.0001). An 88% reduction in circulating IL‐8 concentration was measured in CAI‐treated animals. However, IL‐8 protein secretion and gene expression were increased by CAI treatment in culture (P ≤ 0.01), where CAI caused a dose‐dependent acidification of the culture milieu (P ≤ 0.005). This paradox suggests that IL‐8 production in vitro may be more sensitive to ambient pH than cytosolic calcium. These observations suggest that CAI inhibition of tumor cell VEGF production and endothelial cell response to VEGF results in disruption of signaling between the tumor and its microenvironment, causing a net anti‐angiogenic effect. J. Cell. Physiol. 197: 139–148, 2003© 2003 Wiley‐Liss, Inc.
Acute and chronic leptin treatment mediate contrasting effects on signaling, glucose uptake, and GLUT4 translocation in L6‐GLUT4myc myotubes
Authors: Tajmir Panteha , Kwan Jamie Jun‐Mae , Kessas Mona , Mozammel Shehzin , Sweeney Gary 
Published: August 2003

AbstractWe have previously shown that in L6‐GLUT4myc rat skeletal muscle cells, acute treatment with leptin reduced insulin‐stimulated glucose uptake without altering insulin‐stimulated GLUT4 translocation. In contrast, we show here that the ability of leptin to increase phosphorylation of its receptor and to reduce insulin‐stimulated glucose uptake was lost in cells that were continuously exposed to leptin for 24 h. This desensitization correlated with an increase in expression of suppressor of cytokine signaling‐3 (SOCS‐3). Time course analysis demonstrated that the transition from acute to chronic effects of leptin occurs after 2 h. The desensitization of leptin action at 24 h was not reversed by 30 min washout period prior to re‐exposing cells to leptin. However, despite insulin‐stimulated glucose uptake being unaffected upon 24 h preincubation with leptin, a small but significant decrease (37%) in insulin‐stimulated GLUT4 translocation and phosphorylation of Akt on T308 was detected. Insulin‐stimulated phosphorylation of Akt on S473 or of p38 MAPK were unaffected. These results suggest that the chronic leptin treatment leads to desensitization of leptin signaling yet can simultaneously decrease the ability of insulin to phosphorylate Akt on T308 and translocate GLUT4. However, this does not manifest as a reduction in total glucose uptake into L6 myotubes. J. Cell. Physiol. 197: 122–130, 2003© 2003 Wiley‐Liss, Inc.
Urokinase type plasminogen activator receptor is involved in insulin‐like growth factor‐induced migration of rhabdomyosarcoma cells in vitro
Authors: Gallicchio Marisa A. , Kaun Christoph , Wojta Johann , Binder Bernd , Bach Leon A. 
Published: August 2003

AbstractUrokinase‐type plasminogen activator (uPA) binds to its receptor, uPAR, on the surface of cancer cells, leading to the formation of plasmin. Rhabdomyosarcoma (RMS) cell lines secrete high levels of insulin‐like growth factor II (IGF‐II), suggesting autocrine IGFs play a major role in the unregulated growth and metastasis of RMS. In vitro, IGF‐II and IGF‐I increased migration of RD cells to 124 ± 9% (P < 0.01) and 131 ± 8% (P < 0.05) of control, respectively. IGF‐II‐induced migration was abolished by insulin‐like growth factor binding protein‐6 (IGFBP‐6) (P < 0.01), a relatively specific inhibitor of IGF‐II, and by plasminogen activator inhibitor type 1 (PAI‐1) (P < 0.05). Aprotinin, a plasmin inhibitor, and mannosamine, which inhibits the synthesis of glycosylphosphatidylinositol (GPI), thereby preventing anchorage of GPI‐linked proteins such as uPAR to the cell membrane, also decreased IGF‐II‐ (P < 0.05 for both) but not IGF‐I‐induced migration. [Arg54,Arg55]IGF‐II and [Leu27]IGF‐II, which preferentially bind to the IGF‐I and IGF‐II/mannose‐6‐phosphate receptors (IGF‐II/M6PR), respectively, both induced RD cell migration to 146 ± 8% (P < 0.01) and 120 ± 7% (P < 0.05) of control, respectively. An anti‐uPAR anti‐serum reduced IGF‐II‐ and IGF‐I‐induced migration (P < 0.05 for both). An anti‐low density lipoprotein‐related protein (LRP) anti‐serum reduced IGF‐I‐induced migration (P < 0.05). IGF‐I and ‐II both increased specific 125I‐single chain uPA (scuPA) binding to RD cells in a dose‐dependent manner (P < 0.01). These results suggest involvement of the PA/plasmin system in IGF‐induced migration and indicate important roles these systems may have in RMS metastasis. J. Cell. Physiol. 197: 131–138, 2003© 2003 Wiley‐Liss, Inc.
Glutathione mediates LPS‐stimulated COX‐2 expression via early transient p42/44 MAPK activation
Authors: Chen Jian‐Xiong , Berry Leonard C. , Christman Brian W. , Meyrick Barbara 
Published: August 2003

AbstractThis study examines whether endotoxin (LPS)‐stimulated COX‐2 is modulated by an interaction between mitogen activated protein kinases (MAPK) and intracellular glutathione. Bovine pulmonary artery endothelial cells (BPAEC) were pretreated for 30 min with the following prior to addition of 0.1 μg/ml endotoxin in 2% FBS in medium 199: 5 mM N‐acetylcysteine (NAC) or 5 mM glutathione ethyl ester (GSE) (modulators of intracellular glutathione); 10 μM SB203580 or 25 μM PD98059 (inhibitors of p38 and p42/44 MAPKs, respectively). End‐points included assessment of COX‐1 and COX‐2 gene expression by reverse transcription polymerase chain reaction (RT‐PCR); COX‐1, COX‐2, p38, and p42/44 protein by Western analysis; and measurement of PGE2 and 6‐keto‐PGF1α releases by GC/MS. Both GSE and NAC resulted in significant exacerbation of the LPS‐stimulated increase in COX‐2 gene and protein expression and prostaglandin release, and suppressed the LPS‐induced decrease in COX‐1. LPS caused a biphasic activation of p42/44 MAPKs, an early increase peaking at 30 min and a second sustained phase, lasting up to 24 h; LPS also caused an early and sustained increase p38 MAPK activity. Pretreatment of cells with either GSE or NAC increased the early LPS‐stimulated activation of p42/44 but had little effect on the sustained phase. Inhibition of either p38 or p42/44 MAPKs suppressed LPS‐stimulated COX‐2 gene and protein expression, and prostaglandin release (P < 0.05) but had little effect on COX‐1. We conclude that intracellular glutathione modulates LPS‐stimulated COX‐2 gene expression and prostaglandin synthesis in BPAEC via early activation of p42/44 MAPKs. J. Cell. Physiol. 197: 86–93, 2003© 2003 Wiley‐Liss, Inc.
Sorsby fundus dystrophy mutation Timp3S156C affects the morphological and biochemical phenotype but not metalloproteinase homeostasis
Authors: Soboleva Galina , Geis Birgit , Schrewe Heinrich , Weber Bernhard H.F. 
Published: August 2003

AbstractThe tissue inhibitor of metalloproteinases‐3 (TIMP3) is a multifunctional protein tightly associated with the extracellular matrix (ECM). A specific type of mutation in TIMP3 which results in potentially unpaired cysteine residues at the C‐terminus of the protein has been shown to cause Sorsby fundus dystrophy (SFD), an autosomal dominant retinopathy of late onset. An early finding in SFD is a striking accumulation of protein and lipid material in Bruch's membrane, a multilayered ECM structure located between the choroid and the RPE. To study the molecular mechanisms underlying SFD pathology, we recently generated two mouse lines, one deficient in Timp3 (Timp3−/−) and one carrying an SFD‐related mutation in the orthologous murine Timp3 gene (Timp3S156C/S156C). We now established immortalized fibroblast cells from the mutant mouse strains and provide evidence that the various cell lines display distinct morphological and physiological features that are dependent on the mutational status of the Timp3 protein in the secreted ECM. We show that matrix metalloproteinase (MMP) activity and inhibitory properties of Timp3 are not affected by the SFD‐associated mutation. We further demonstrate that Timp3S156C protein accumulates in the ECM of the mutant fibroblast cells and that this accumulation is not due to a prolonged turnover rate of mutant vs. normal Timp3. We also show that the relative abundance of mutant and normal Timp3 in the ECM has no measurable effects on cellular phenotypes. Together, these findings suggest (i) a functional role of normal Timp3 in pathways determining cellular morphology and (ii) a loss of this particular function as a consequence of the Ser156Cys mutation. We therefore hypothesize that SFD pathogenesis is due to a loss‐of‐function mutation in TIMP3. J. Cell. Physiol. 197: 149–156, 2003© 2003 Wiley‐Liss, Inc.
Catalytic activity of Cdk9 is required for nuclear co‐localization of the Cdk9/cyclin T1 (P‐TEFb) complex
Authors: Napolitano Giuliana , Majello Barbara , Lania Luigi 
Published: August 2003

AbstractCdk9 and its binding partner cyclin T1 comprise the positive elongation factor b (P‐TEFb). P‐TEFb phosphorylates the RNA polymerase II carboxyl‐terminal‐domain (CTD) allowing efficient transcription elongation. Recent studies showed that Cdk9 is a predominant nuclear protein, and here we investigated the functional requirement for nuclear localization of Cdk9. We found that the catalytic inactive kinase mutant (Cdk9dn) fails to accumulate in the nucleus showing a diffuse sub‐cellular localization. In addition to the catalityc activity, nuclear localization of Cdk9 protein requires the presence of the phospho‐acceptor sites at the C‐terminus tail. Finally, enforced expression of wild‐type cyclinT1, which enhances nuclear localization of Cdk9wt, fails to direct the Cdk9 mutants to the nucleus. Collectively, these findings implicate that nuclear localization of Cdk9 requires auto‐phosphorylation of the kinase, and highlight the presence of a regulatory mechanism underlying the nuclear localization of the P‐TEFb complex. J. Cell. Physiol. 197: 1–7, 2003© 2003 Wiley‐Liss, Inc.