Biomedical subjects

M Noda

Publications and source records attributed to M Noda.

At least 55 records · Page 3Linked to original sources

PubMed2002

[Catamenial pneumothorax long-term monitored by serum levels of CA 125; report of a case].

A 46-year-old woman was admitted to our hospital because of the repeating right chest pain. Chest X-ray showed a right pneumothorax. This symptom corresponded with her mensturations and elevated serum levels of CA 125. We diagnosed catamenial pneumothorax. Hormones therapy was not performed because severe side effects. For that reason we performed thoracoscopic surgery. We found many little sized fistulas on diaphragm and blue berry spots on right upper lobe during the operation. She didn't recurrence for 2 years after that operation.

CA-125 Antigen↗

PubMed2002

[Pleomorphic adenoma of the lung; report of a case].

A 67-year-old woman was admitted because of an abnormal shadow on the chest X-ray film. Chest computed tomography (CT) film revealed a peripheral mass in the middle lower lobe of the lung. We performed open lung biopsy and diagnosed as a benign epithelial adenoma but not ruled out adenocarcinoma completely by intraoperative examination of frozen sections. We operated right middle lobectomy and mediastinal lymph nodes dissections. Histological examination confirmed pleomorphic adenoma. We examined salivary glands, but didn't find the focus of that. The patient had been well for three years postoperatively.

Adenoma, Pleomorphic↗

PubMed2001

The membrane-anchored MMP inhibitor RECK is a key regulator of extracellular matrix integrity and angiogenesis.

Matrix metalloproteinases (MMPs) are essential for proper extracellular matrix remodeling. We previously found that a membrane-anchored glycoprotein, RECK, negatively regulates MMP-9 and inhibits tumor invasion and metastasis. Here we show that RECK regulates two other MMPs, MMP-2 and MT1-MMP, known to be involved in cancer progression, that mice lacking a functional RECK gene die around E10.5 with defects in collagen fibrils, the basal lamina, and vascular development, and that this phenotype is partially suppressed by MMP-2 null mutation. Also, vascular sprouting is dramatically suppressed in tumors derived from RECK-expressing fibrosarcoma cells grown in nude mice. These results support a role for RECK in the regulation of MMP-2 in vivo and implicate RECK downregulation in tumor angiogenesis.

Animals↗

PubMed2001

Haematopoietic cell-specific CDM family protein DOCK2 is essential for lymphocyte migration.

Cell migration is a fundamental biological process involving membrane polarization and cytoskeletal dynamics, both of which are regulated by Rho family GTPases. Among these molecules, Rac is crucial for generating the actin-rich lamellipodial protrusion, a principal part of the driving force for movement. The CDM family proteins, Caenorhabditis elegans CED-5, human DOCK180 and Drosophila melanogaster Myoblast City (MBC), are implicated to mediate membrane extension by functioning upstream of Rac. Although genetic analysis has shown that CED-5 and Myoblast City are crucial for migration of particular types of cells, physiological relevance of the CDM family proteins in mammals remains unknown. Here we show that DOCK2, a haematopoietic cell-specific CDM family protein, is indispensable for lymphocyte chemotaxis. DOCK2-deficient mice (DOCK2-/-) exhibited migration defects of T and B lymphocytes, but not of monocytes, in response to chemokines, resulting in several abnormalities including T lymphocytopenia, atrophy of lymphoid follicles and loss of marginal-zone B cells. In DOCK2-/- lymphocytes, chemokine-induced Rac activation and actin polymerization were almost totally abolished. Thus, in lymphocyte migration DOCK2 functions as a central regulator that mediates cytoskeletal reorganization through Rac activation.

Animals↗

PubMed2001

Ventroptin: a BMP-4 antagonist expressed in a double-gradient pattern in the retina.

In the visual system, the establishment of the anteroposterior and dorsoventral axes in the retina and tectum during development is important for topographic retinotectal projection. We identified chick Ventroptin, an antagonist of bone morphogenetic protein 4 (BMP-4), which is mainly expressed in the ventral retina, not only with a ventral high-dorsal low gradient but also with a nasal high-temporal low gradient at later stages. Misexpression of Ventroptin altered expression patterns of several topographic genes in the retina and projection of the retinal axons to the tectum along both axes. Thus, the topographic retinotectal projection appears to be specified by the double-gradient molecule Ventroptin along the two axes.

Alternative Splicing↗

PubMed2001

Identification of human endomucin-1 and -2 as membrane-bound O-sialoglycoproteins with anti-adhesive activity.

Using a signal sequence trap method and database search, we identified a series of human cDNAs encoding two structurally related type I membrane proteins of approximately 25 kDa with multiple glycosylation motifs. These genes, termed endomucin-1/-2, are expressed in several human tissues including heart, kidney, and lung. Exogenously expressed human endomucin-1/-2 proteins were modified into 80-120 kDa glycoproteins, which were susceptible to O-sialoglycoprotein endopeptidase digestion. Transient overexpression of endomucin-1/-2 reduced the number of adhesion plaques and reduced cell attachment to the substrate. This phenotype was suppressed by laminin or the protein kinase inhibitor staurosporine. Our findings suggest that human endomucin-1/-2 negatively regulate cell adhesion to the extracellular matrix.

Amino Acid Sequence↗

PubMed2001

Identification of GIT1/Cat-1 as a substrate molecule of protein tyrosine phosphatase zeta /beta by the yeast substrate-trapping system.

We used a genetic method, the yeast substrate-trapping system, to identify substrates for protein tyrosine phosphatases zeta (PTPzeta/RPTPbeta). This method is based on the yeast two-hybrid system, with two essential modifications: conditional expression of protein tyrosine kinase v-src (active src) to tyrosine-phosphorylate the prey proteins and screening by using a substrate-trap mutant of PTPzeta (PTPzeta-D1902A) as bait. By using this system, several substrate candidates for PTPzeta were isolated. Among them, GIT1/Cat-1 (G protein-coupled receptor kinase-interactor 1/Cool-associated, tyrosine-phosphorylated 1) was examined further. GIT1/Cat-1 bound to PTPzeta-D1902A dependent on the substrate tyrosine phosphorylation. Tyrosine-phosphorylated GIT1/Cat-1 was dephosphorylated by PTPzeta in vitro. Immunoprecipitation experiments indicated that PTPzeta-D1902A and GIT1/Cat-1 form a stable complex also in mammalian cells. Immunohistochemical analyses revealed that PTPzeta and GIT1/Cat-1 were colocalized in the processes of pyramidal cells in the hippocampus and neocortex in rat brain. Subcellular colocalization was further verified in the growth cones of mossy fibers from pontine explants and in the ruffling membranes and processes of B103 neuroblastoma cells. Moreover, pleiotrophin, a ligand for PTPzeta, increased tyrosine phosphorylation of GIT1/Cat-1 in B103 cells. All these results indicate that GIT1/Cat-1 is a substrate molecule of PTPzeta.

Animals↗

PubMed2001

Vitamin D(3) enhances the expression of I-mfa, an inhibitor of the MyoD family, in osteoblasts.

I-mfa (inhibitor of the MyoD family) is a transcription modulator that binds to and suppresses the transcriptional activity of MyoD family members. I-mfa transcripts are expressed in sclerotome, suggesting a role of I-mfa in skeletogenesis. The aim of this study was to examine the expression and regulation of I-mfa in osteoblasts. We found that I-mfa is expressed at a low level in an osteoblast-like cell line, MC3T3E1, and a pluripotent differentiation modulator, 1,25-dihydroxyvitamin D(3), specifically enhanced I-mfa mRNA expression. This effect was completely blocked by the presence of an RNA polymerase inhibitor, but not by a protein synthesis inhibitor, suggesting that 1,25-dihydroxyvitamin D(3) upregulates transcription of the I-mfa gene without requirement for new protein synthesis. Western blot analysis indicated that 1,25-dihydroxyvitamin D(3) increased the I-mfa protein levels severalfold in MC3T3E1 cells. I-mfa expression was also observed in primary mouse calvaria cells and ROS17/2.8 cells and 1,25-dihydroxyvitamin D(3) enhanced I-mfa expression in these cells. These data indicate that I-mfa is a novel transcriptional regulator gene expressed in osteoblasts and that its level is under the control of 1,25-dihydroxyvitamin D(3).

Animals↗

PubMed2001

A missense mutation of the Na+ channel alpha II subunit gene Na(v)1.2 in a patient with febrile and afebrile seizures causes channel dysfunction.

Generalized epilepsy with febrile seizures plus (GEFS+), a clinical subset of febrile seizures (FS), is characterized by frequent episodes beyond 6 years of age (FS+) and various types of subsequent epilepsy. Mutations in beta1 and alpha(I)-subunit genes of voltage-gated Na(+) channels have been associated with GEFS+1 and 2, respectively. Here, we report a mutation resulting in an amino acid exchange (R188W) [corrected] in the gene encoding the alpha-subunit of neuronal voltage-gated Na(+) channel type II (Na(v)1.2) in a patient with FS associated with afebrile seizures. The mutation R188W [corrected] occurring on Arg(187), a highly conserved residue among voltage-gated Na(+) channels, was not found in 224 alleles of unaffected individuals. Whole-cell patch clamp recordings on human embryonic kidney (HEK) cells expressing a rat wild-type (rNa(v)1.2) and the corresponding mutant channels showed that the mutant channel inactivated more slowly than wild-type whereas the Na(+) channel conductance was not affected. Prolonged residence in the open state of the R188W [corrected] mutant channel may augment Na(+) influx and thereby underlie the neuronal hyperexcitability that induces seizure activity. Even though a small pedigree could not show clear cosegregation with the disease phenotype, these findings strongly suggest the involvement of Na(v)1.2 in a human disease and propose the R188W [corrected] mutation as the genetic defect responsible for febrile seizures associated with afebrile seizures.

Amino Acid Substitution↗

PubMed2001

Haptotactic migration induced by midkine. Involvement of protein-tyrosine phosphatase zeta. Mitogen-activated protein kinase, and phosphatidylinositol 3-kinase.

Midkine, a heparin-binding growth factor, plays a critical role in cell migration causing suppression of neointima formation in midkine-deficient mice. Here we have determined the molecules essential for midkine-induced migration. Midkine induced haptotaxis of osteoblast-like cells, which was abrogated by the soluble form of midkine or pleiotrophin, a midkine-homologous protein. Chondroitin sulfate B, E, chondroitinase ABC, B, and orthovanadate, an inhibitor of protein-tyrosine phosphatase, suppressed the migration. Supporting these data, the cells examined expressed PTPzeta, a receptor-type protein-tyrosine phosphatase that exhibits high affinity to both midkine and pleiotrophin and harbors chondroitin sulfate chains. Furthermore, strong synergism between midkine and platelet-derived growth factor in migration was detected. The use of specific inhibitors demonstrated that mitogen-activated protein (MAP) kinase and protein-tyrosine phosphatase were involved in midkine-induced haptotaxis but not PDGF-induced chemotaxis, whereas phosphatidylinositol 3 (PI3)-kinase and protein kinase C were involved in both functions. Midkine activated both PI3-kinase and MAP kinases, the latter activation was blocked by a PI3-kinase inhibitor. Midkine further recruited PTPzeta and PI3-kinase. These results indicate that PTPzeta and concerted signaling involving PI3-kinase and MAP kinase are required for midkine-induced migration and demonstrate for the first time the synergism between midkine and platelet-derived growth factor in cell migration.

Animals↗

PubMed2001

Involvement of ADP-ribosylation factor 1 in cholera toxin-induced morphological changes of Chinese hamster ovary cells.

ADP-ribosylation factor 1 (ARF1) was originally found as a cofactor in CT-catalyzed ADP-ribosylation of Galpha(s) but is now known to participate in vesicle trafficking. We asked whether ARF1 function in vesicular trafficking is necessary for CT-induced morphological changes in Chinese hamster ovary (CHO) cells, which result from increased intracellular cAMP. Brefeldin A treatment of cells suppressed CT action, confirming a requirement for Golgi integrity. Overexpression of a GFP-ARF1 fusion protein did not affect the morphological changes induced by CT, but changes were reduced in cells overexpressing guanine nucleotide exchange-defective ARF1(T31N) or GTP hydrolysis-deficient ARF1(Q71L) mutants. In cells expressing these mutants, 8-bromo-cAMP induced changes similar to those seen in cells transfected with ARF1 or vector. Inhibition of CT action was specific for mutants of ARF1 and not reproduced by analogous mutants of ARF5 or ARF6. ARF1(Q71L) was mostly colocalized with betaCOP, but ARF5(Q71L) less so. ARF6(Q67L) did not colocalize with betaCOP and was partially associated with the plasma membrane. These data are consistent with the conclusion that ARF1 influenced CT action in cells by its specific function in the vesicular transport pathway used by CT to travel from plasma membrane to Golgi to ER.

8-Bromo Cyclic Adenosine Monophosphate↗

PubMed2001

c-IAP2 is induced by ionizing radiation through NF-kappaB binding sites.

Transcriptional promoters responsive to low doses of X-irradiation may be useful in developing a new strategy in gene therapy combined with conventional radiotherapy. The retrovirus-mediated gene trap screening identified c-IAP2 as one of genes possessing such promoters. The analysis of the cis-elements responsive to X-irradiation in c-IAP2 promoter revealed that the NF-kappaB binding sites were necessary and sufficient for the X-ray-responsiveness. We constructed the plasmid p4NFB-BAX, which had four tandem repeats of the NF-kappaB binding sites of c-IAP2 promoter (4NFB) and a suicide gene BAX under the control of 4NFB. The human tumor cells transfected with p4NFB-BAX significantly reduced the number of cells that survived 2 Gy irradiation.

Adenocarcinoma↗

PubMed2001

Enhancement of osteoclastic bone resorption and suppression of osteoblastic bone formation in response to reduced mechanical stress do not occur in the absence of osteopontin.

Reduced mechanical stress to bone in bedridden patients and astronauts leads to bone loss and increase in fracture risk which is one of the major medical and health issues in modern aging society and space medicine. However, no molecule involved in the mechanisms underlying this phenomenon has been identified to date. Osteopontin (OPN) is one of the major noncollagenous proteins in bone matrix, but its function in mediating physical-force effects on bone in vivo has not been known. To investigate the possible requirement for OPN in the transduction of mechanical signaling in bone metabolism in vivo, we examined the effect of unloading on the bones of OPN(-/-) mice using a tail suspension model. In contrast to the tail suspension-induced bone loss in wild-type mice, OPN(-/-) mice did not lose bone. Elevation of urinary deoxypyridinoline levels due to unloading was observed in wild-type but not in OPN(-/-) mice. Analysis of the mechanisms of OPN deficiency-dependent reduction in bone on the cellular basis resulted in two unexpected findings. First, osteoclasts, which were increased by unloading in wild-type mice, were not increased by tail suspension in OPN(-/-) mice. Second, measures of osteoblastic bone formation, which were decreased in wild-type mice by unloading, were not altered in OPN(-/-) mice. These observations indicate that the presence of OPN is a prerequisite for the activation of osteoclastic bone resorption and for the reduction in osteoblastic bone formation in unloaded mice. Thus, OPN is a molecule required for the bone loss induced by mechanical stress that regulates the functions of osteoblasts and osteoclasts.

Amino Acids↗

PubMed2001

Dual antitumor effects of 5-fluorouracil on the cell cycle in colorectal carcinoma cells: a novel target mechanism concept for pharmacokinetic modulating chemotherapy.

5-Fluorouracil (5-FU) is one of the most widely used anticancer agents for advanced colorectal carcinoma, but its response rate is only 15%. The "pharmacokinetic modulating chemotherapy" (PMC) regimen that we have advocated has proved to be highly effective in treating colorectal carcinoma. PMC consists of a continuous i.v. infusion of 5-FU over 24 h for 1day a week at 600 mg/m2/day, and an oral dose of uracil-tegafur (UFT), a 5-FU derivative, at 400 mg/day for 5-7 days per week, repeated every week for more than 6 months. Assays of 5-FU in 23 patients receiving this treatment showed serum concentrations ranging from 88 to 1,323 ng/ml. We then analyzed the effects of clinically relevant concentrations of 5-FU found in colorectal cancer patients treated with the PMC regimen on the growth of three human colorectal adenocarcinoma cell lines, SW480 and COLO320DM (mutant p53) and HCT116 (wild-type p53). Exposure of these three cell lines to 5-FU resulted in growth inhibition in a dose-dependent manner. Exposure to 100 ng/ml of 5-FU in SW480 and COLO320DM caused G1 arrest after 24 h and G2 arrest after 72-144 h, and only a minority of the cell population showed apoptotic features, which indicated that most of the cells were killed through mitotic catastrophe, nonapoptotic cell death. On the contrary, exposure to 1000 ng/ml of 5-FU in SW480 and COLO320DM resulted in G1-S-phase arrest and the induction of apoptosis throughout the experimental period. Nuclear cyclin B1 expression was markedly induced with exposure to 100 ng/ml of 5-FU in SW480 and COLO320DM; and expression of 14-3-3sigma protein, a cell cycle inhibitor in the GG phase, was induced in SW480. ICT116 responded to lower concentrations of 5-FU more rapidly: G2 arrest was seen after 24-72 h of exposure to 10 ng/ml of 5-FU, and G,1rrest was seen after 12-24 h of exposure to 100 ng/ml. These results show that 5-FU acts via two different pathways, depending on dose: (a) G,1S-phase cell cycle arrest and apoptosis at 1,000 ng/ml in SW480 and COLO320DM, and 100 ng/ml in HCT116; and (b) G2-M-phase cell cycle arrest and mitotic catastrophe at 100 ng/ll in SW480 and COLO320DM, and 10 ng/ml in HCT116. These results suggest that the efficacy of our PMC regimen is based on targeting at least two different phases of the cell cycle. In our clinical trial, we showed efficacy independent of p53 status, ascertained by cell kinetic analysis in vitro, which may lead to a novel concept of schedule-oriented biochemical modulation of this drug.

Adenocarcinoma↗

PubMed2001

Parathyroid hormone-induced bone resorption does not occur in the absence of osteopontin.

Osteopontin is an RGDS-containing protein that acts as a ligand for the alpha(v)beta(3) integrin, which is abundantly expressed in osteoclasts, cells responsible for bone resorption in osteopenic diseases such as osteoporosis and hyperparathyroidism. However, the role of osteopontin in the process of bone resorption has not yet been fully understood. Therefore, we investigated the direct function of osteopontin in bone resorption using an organ culture system. The amount of (45)Ca released from the osteopontin-deficient bones was not significantly different from the basal release from wild type bones. However, in contrast to the parathyroid hormone (PTH) enhancement of the (45)Ca release from wild type bones, PTH had no effect on (45)Ca release from organ cultures of osteopontin-deficient bones. Because PTH is located upstream of receptor activator of NF-kappaB ligand (RANKL), that directly promotes bone resorption, we also examined the effect of RANKL. Soluble RANKL with macrophage-colony stimulating factor enhanced (45)Ca release from the bones of wild type fetal mice but not from the bones of osteopontin-deficient mice. To obtain insight into the cellular mechanism underlying the phenomena observed in osteopontin-deficient bone, we investigated the number of tartrate-resistant acid phosphatase (TRAP)-positive cells in the bones subjected to PTH treatment in cultures. The number of TRAP-positive cells was increased significantly by PTH in wild type bone; however, no such PTH-induced increase in TRAP-positive cells was observed in osteopontin-deficient bones. These results indicate that the absence of osteopontin suppressed PTH-induced increase in bone resorption via preventing the increase in the number of osteoclasts in the local milieu of bone.

Animals↗

PubMed2001

Identification of a novel thioredoxin-related transmembrane protein.

We recently identified a series of transforming growth factor-beta-responsive genes in A549 human adenocarcinoma cell line by a gene trap screening method. Here we report the molecular cloning and characterization of one of these genes, designated TMX, that encodes a novel protein of 280 amino acid residues. The TMX protein possesses an N-terminal signal peptide followed by one thioredoxin (Trx)-like domain with a unique active site sequence, Cys-Pro-Ala-Cys, and a potential transmembrane domain. There are putative TMX homologs with identical active site sequences in the Caenorhabditis elegans and Drosophila genomes. Using recombinant proteins expressed in Escherichia coli, we demonstrated the activity of the Trx domain of TMX to cleave the interchain disulfide bridges in insulin in vitro. The TMX transcript is widely expressed in normal human tissues, and subcellular fractionation and immunostaining for an epitope-tagged TMX protein suggest that TMX is predominantly localized in the endoplasmic reticulum (ER). When TMX was expressed in HEK293 cells, it significantly suppressed the apoptosis induced by brefeldin A, an inhibitor of ER-Golgi transport. This activity was abolished when two Cys residues in the active site sequence were mutated to Ser, suggesting that the Trx-like activity of TMX may help relieve ER stress caused by brefeldin A.

Adenocarcinoma↗

PubMed2001

Spontaneous mutation in Mitf gene causes osteopetrosis in silver homozygote quail.

Silver homozygous quail was recently reported to have mutations in Mitf gene. Although numerous mutations in Mitf gene have been reported in mice, no mutations corresponding to the mutation in the homozygous silver (B/B) quail in Mitf gene have been reported to cause defects in pigmentation and bone. Therefore, we investigated the bones of the B/B homozygotes. Comparison of the bones of the B/B homozygotes with those of wild-type by X-ray examination revealed osteopetrosis in the long bones of B/B homozygotes. However, osteopetrosis in B/B homozygotes was less severe than that observed in mi/mi mice. Histological examination showed that there were less TRAP-positive multinucleated cells in the trabecular bones in B/B homozygote tibia than in the wild type. In vitro osteoclastogenesis study also suggested that formation of TRAP-positive multinucleated cell was suppressed in the marrow cells of the long bones of the B/B homozygotes. Furthermore, overexpression of chicken Mitf via retroviral transfection into B/B homozygote bone marrow cells in cultures increased the number of TRAP-positive cells 2-3 fold more than that in control. These results indicated that in addition to the previously reported defect in melanogenesis, osteoclastogenesis was inhibited in B/B homozygotes. These results indicate that the novel mutations in Mitf gene observed in the B/B homozygote quail impair osteoclastic bone resorption.

Aging↗

PubMed2001

Transcriptional suppression of Sox9 expression in chondrocytes by retinoic acid.

SOX9 is a transcription factor that is expressed in chondrocytes and regulates expression of chondrocyte phenotype related genes. Expression of these genes is known to be suppressed by retinoic acid (RA). We, therefore, examined whether the Sox9 gene expression is regulated by RA in chondrocytes. RA treatment suppressed Sox9 mRNA expression in primary chondrocytes prepared from newborn mouse rib cartilage within 12 h and this suppression lasted at least up to 24 h. The RA suppression of Sox9 mRNA levels was dose-dependent starting at 0.5 microM with a maximum at 1 microM. Nuclear run-on assays revealed that RA reduced the rate of transcription of Sox9 gene. Finally, Western blot analysis indicated that RA suppressed SOX9 protein levels in these chondrocytes. Furthermore, overexpression of SOX9 reversed RA suppression of Col2a1 enhancer activity. These observations indicate that RA suppresses Sox9 gene expression in chondrocytes at least in part through transcriptional events. J. Cell. Biochem. Suppl. 36: 71-78, 2001.

Animals↗