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1.
Clin Transl Oncol ; 18(6): 625-31, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26459257

ABSTRACT

PURPOSE: To analyze the expression of c-Met, and to investigate correlations between the expression of c-Met, clinicopathologic variables, and survival in patients undergoing curative surgery followed by adjuvant chemoradiotherapy for extrahepatic bile duct (EHBD) cancer. METHODS: Ninety EHBD cancer patients who underwent curative resection followed by adjuvant chemoradiotherapy were enrolled. Expression of c-Met was assessed with immunohistochemical staining on tissue microarray. The correlation between clinicopathologic variables and survival outcomes was evaluated using Kaplan-Meier method and Cox proportional hazard model. RESULTS: On univariate analysis, 66 patients (76.7 %) showed c-Met expression. c-Met expression had a significant impact on 5-year overall survival (OS) (43.0 % in c-Met(+) vs. 25.0 % in c-Met(-), p = 0.0324), but not on loco-regional relapse-free survival or distant metastasis-free survival (DMFS). However, on multivariate analysis incorporating tumor location and nodal involvement, survival difference was not maintained (p = 0.2940). Tumor location was the only independent prognostic factor predicting OS (p = 0.0089). Hilar location tumors, nodal involvement, and poorly differentiated tumors were all identified as independent prognostic factors predicting inferior DMFS (p = 0.0030, 0.0013, and 0.0037, respectively). CONCLUSIONS: This study showed that c-Met expression was not associated with survival outcomes in EHBD cancer patients undergoing curative resection followed by adjuvant chemoradiotherapy. Further studies are needed to fully elucidate the prognostic value of c-Met expression in these patients.


Subject(s)
Bile Duct Neoplasms/pathology , Biomarkers, Tumor/analysis , Proto-Oncogene Proteins c-met/biosynthesis , Adult , Aged , Bile Duct Neoplasms/mortality , Bile Duct Neoplasms/therapy , Bile Ducts, Extrahepatic/pathology , Chemoradiotherapy, Adjuvant , Digestive System Surgical Procedures , Disease-Free Survival , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Prognosis , Proto-Oncogene Proteins c-met/analysis , Tissue Array Analysis , Young Adult
2.
J Steroid Biochem Mol Biol ; 164: 337-343, 2016 11.
Article in English | MEDLINE | ID: mdl-26232637

ABSTRACT

The differentiation of embryonic mesenchymal cells into chondrocytes and the subsequent formation of a cartilaginous scaffold that enables the formation of long bones are hallmarks of endochondral ossification. During this process, chondrocytes undergo a remarkable sequence of events involving proliferation, differentiation, hypertrophy and eventually apoptosis. Forkhead Box O (FoxO) transcription factors (TFs) are well-known regulators of such cellular processes. Although FoxO3a was previously shown to be regulated by 1,25-dihydroxyvitamin D3 in osteoblasts, a possible role for this family of TFs in chondrocytes during endochondral ossification remains largely unstudied. By crossing Collagen2-Cre mice with FoxO1lox/lox;FoxO3alox/lox;FoxO4lox/lox mice, we generated mice in which the three main FoxO isoforms were deleted in growth plate chondrocytes (chondrocyte triple knock-out; CTKO). Intriguingly, CTKO neonates showed a distinct elongation of the hypertrophic zone of the growth plate. CTKO mice had increased overall body and tail length at eight weeks of age and suffered from severe skeletal deformities at older ages. CTKO chondrocytes displayed decreased expression of genes involved in redox homeostasis. These observations illustrate the importance of FoxO signaling in chondrocytes during endochondral ossification.


Subject(s)
Bone and Bones/metabolism , Chondrocytes/metabolism , Forkhead Box Protein O1/genetics , Forkhead Box Protein O3/genetics , Forkhead Transcription Factors/genetics , Osteogenesis/genetics , Animals , Bone and Bones/cytology , Cell Cycle Proteins , Cell Differentiation , Cell Proliferation , Chondrocytes/cytology , Collagen Type II/genetics , Collagen Type II/metabolism , Crosses, Genetic , Female , Forkhead Box Protein O1/deficiency , Forkhead Box Protein O3/deficiency , Forkhead Transcription Factors/deficiency , Gene Expression Profiling , Gene Expression Regulation, Developmental , Integrases/genetics , Integrases/metabolism , Male , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Mice , Mice, Transgenic , Oxidoreductases/genetics , Oxidoreductases/metabolism , Primary Cell Culture , Signal Transduction
3.
Cell Death Differ ; 22(12): 2034-45, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26470727

ABSTRACT

Forkhead transcription factor family O (FoxO) maintains adult stem cell reserves by supporting their long-term proliferative potential. MicroRNAs (miRs) regulate neuronal stem/progenitor cell (NSPC) proliferation and differentiation during neural development by controlling the expression of a specific set of target genes. In the neurogenic subventricular zone, FoxO1 is specifically expressed in NSPCs and is no longer detected during the transition to neuroblast stage, forming an inverse correlation with miR-9 expression. The 3'-untranslated region of FoxO1 contains a conserved target sequence of miR-9 and FoxO1 expression is coordinated in concert with miR-9 during neuronal differentiation. Our study demonstrates that FoxO1 contributes to NSPC fate decision through its cooperation with the Notch signaling pathway.


Subject(s)
Forkhead Transcription Factors/metabolism , 3' Untranslated Regions , Animals , Base Sequence , Cell Differentiation , Cells, Cultured , Doublecortin Domain Proteins , Forkhead Box Protein O1 , Forkhead Transcription Factors/chemistry , Forkhead Transcription Factors/genetics , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Microtubule-Associated Proteins/genetics , Microtubule-Associated Proteins/metabolism , Nestin/genetics , Nestin/metabolism , Neural Stem Cells/cytology , Neural Stem Cells/metabolism , Neuropeptides/genetics , Neuropeptides/metabolism , Receptors, Notch/genetics , Receptors, Notch/metabolism , Sequence Alignment , Signal Transduction , Tubulin/genetics , Tubulin/metabolism
4.
Br J Cancer ; 110(11): 2688-99, 2014 May 27.
Article in English | MEDLINE | ID: mdl-24809777

ABSTRACT

BACKGROUND: c-MYC copy number gain (c-MYC gain) has been associated with aggressive behaviour in several cancers. However, the role of c-MYC gain has not yet been determined in lung adenocarcinomas classified by genetic alterations in epidermal growth factor receptor (EGFR), KRAS, and anaplastic lymphoma kinase (ALK) genes. We investigated the clinicopathologic and prognostic significance of c-MYC gain for disease-free survival (DFS) and overall survival (OS) according to EGFR, KRAS, and ALK gene status and stages in lung adenocarcinomas. METHODS: In 255 adenocarcinomas resected in Seoul National University Bundang Hospital from 2003 to 2009, fluorescence in situ hybridisation (FISH) with c-MYC probe and centromeric enumeration probe 8 (CEP8) was analysed using tissue microarray containing single representative core per each case. EGFR (codon 18 to 21) and KRAS (codon 12, 13, and 61) mutations were analysed by polymerase chain reaction and direct sequencing method from formalin-fixed, paraffin-embedded tissue sections. ALK rearrangement was determined by FISH method. c-MYC gain was defined as >2 copies per nucleus, chromosome 8 gain as ⩾3 copies per nucleus, and gain of c-MYC:CEP8 ratio (hereafter, c-MYC amplification) as ⩾2. RESULTS: We observed c-MYC gain in 20% (51 out of 255), chromosome 8 gain in 5.5% (14 out of 255), c-MYC amplification in 2.4% (6 out of 255), EGFR mutation in 49.4% (118 out of 239), KRAS mutation in 5.7% (7 out of 123), and ALK rearrangement in 4.9% (10 out of 205) of lung adenocarcinomas. c-MYC gain was observed in 19% (22 out of 118) of patients with lung adenocarcinomas with an EGFR mutation, but not in any patients with a KRAS mutation, or an ALK rearrangement. c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor in the full cohort of lung adenocarcinoma (P=0.022, hazard ratio (HR)=1.71, 95% confidence interval (CI), 1.08-2.69 for DFS; P=0.032, HR=2.04, 95% CI, 1.06-3.91 for OS), as well as in stage I subgroup (P=0.023, HR=4.70, 95% CI, 1.24-17.78 for DFS; P=0.031, HR=4.65, 95% CI, 1.15-18.81 for OS), and in EGFR-mutant subgroup (P=0.022; HR=2.14; 95% CI, 1.11-4.10 for DFS). CONCLUSIONS: c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor for DFS and OS in lung adenocarcinomas, both in full cohort and stage I cancer, and possibly for DFS in EGFR-mutant adenocarcinomas. Additional studies are required to determine if patients with lung adenocarcinoma with c-MYC gain are candidates for additional first-line treatment to mitigate their increased risk for disease progression and death.


Subject(s)
Adenocarcinoma/genetics , Gene Amplification , Lung Neoplasms/genetics , Proto-Oncogene Proteins c-myc/genetics , Adenocarcinoma/mortality , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Anaplastic Lymphoma Kinase , Chromosomes, Human, Pair 8/genetics , DNA Copy Number Variations , Disease-Free Survival , ErbB Receptors/genetics , Female , Gene Dosage , Genetic Association Studies , Humans , Kaplan-Meier Estimate , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Prognosis , Proportional Hazards Models , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins p21(ras) , ROC Curve , Receptor Protein-Tyrosine Kinases/genetics , Tissue Array Analysis , ras Proteins/genetics
5.
Clin Nephrol ; 75(2): 165-70, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21255547

ABSTRACT

Thrombotic microangiopathy (TMA) is a rare renal complication accompanied with Castleman's disease. We report the first case of TMA combined plasma cell type multicentric Castleman's disease (MCD) which was successfully treated with rituximab and corticosteroid. A previously healthy 60-year-old Korean man was admitted due to acute renal failure, thrombocytopenia, and multiple lymphadenopathies. The result of lymph node biopsy was plasma cell type Castleman's disease and TMA was revealed by kidney biopsy. After treatment with rituximab, prednisolone and temporary hemodialysis, complete remission was achieved. The combination of corticosteroid and rituximab was associated with improvement for this patient.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , Antibodies, Monoclonal, Murine-Derived/therapeutic use , Castleman Disease/drug therapy , Immunologic Factors/therapeutic use , Kidney Diseases/drug therapy , Thrombotic Microangiopathies/drug therapy , Biopsy , Castleman Disease/complications , Castleman Disease/diagnosis , Drug Therapy, Combination , Humans , Kidney/pathology , Kidney Diseases/diagnosis , Kidney Diseases/etiology , Lymph Nodes/pathology , Male , Middle Aged , Renal Dialysis , Rituximab , Severity of Illness Index , Thrombotic Microangiopathies/diagnosis , Thrombotic Microangiopathies/etiology , Tomography, X-Ray Computed , Treatment Outcome
7.
Histopathology ; 53(2): 205-17, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18752503

ABSTRACT

AIMS: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with various genetic alterations. The aim was to investigate MYC, Bcl-2 and Bcl-6 translocations and copy number changes in adult DLBCLs to evaluate their clinicopathological features and prognostic implications. METHODS AND RESULTS: Gene status was examined using fluorescence in situ hybridization (FISH), and the results were analysed in the context of germinal centre B-cell (GCB) and non-GCB type of DLBCL based on immunohistochemistry. MYC translocation was observed in 9% (14 of 156), and an increased copy number (ICN) in 7.1% (11 of 156). MYC translocation was more common in GCB type (22%) than in non-GCB type (4.9%), and associated with advanced International Prognostic Index (IPI). MYC aberration, i.e. translocation or increased copy number (ICN), was significantly associated with shorter overall survival, especially for the GCB type. Bcl-2 translocation was rare (3.4%, five of 145), and ICN was observed in 11.7% (17 of 145), more frequently in non-GCB type (16%) than in GCB type (2.5%). Bcl-2 aberration tended to have an adverse effect on survival. In multivariate analysis, MYC ICN was an independent poor prognostic factor. CONCLUSIONS: Analyses of MYC and Bcl-2 status, i.e. translocation and ICN, in the context of DLBCL phenotype might help predict prognosis and determine therapeutic strategies.


Subject(s)
Gene Dosage , Germinal Center/pathology , Lymphoma, Large B-Cell, Diffuse/diagnosis , Lymphoma, Large B-Cell, Diffuse/genetics , Proto-Oncogene Proteins c-myc/genetics , Translocation, Genetic , Adult , Aged , Aged, 80 and over , B-Lymphocytes/pathology , Female , Humans , In Situ Hybridization, Fluorescence , Lymphoma, Large B-Cell, Diffuse/mortality , Lymphoma, Large B-Cell, Diffuse/pathology , Male , Middle Aged , Predictive Value of Tests , Prognosis , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-6/genetics
8.
J Pathol ; 213(2): 170-9, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17768706

ABSTRACT

NK/T-cell lymphoma (NKTL) is strongly associated with latent Epstein-Barr virus (EBV) infection. Recently, latent membrane protein 1 (LMP1), an EBV oncoprotein, was reported to activate the phosphatidylinositol-3 kinase (PI3K)/Akt pathway for cell survival. Because geldanamycin (GA) and its derivative, 17-allylamino-17-demethoxygeldanamycin (17-AAG), exhibit anti-tumour activity by degrading HSP90 client proteins, including Akt, we investigated the effect of GA and 17-AAG on the survival of NKTL cell lines. EBV-positive NKTL cell lines, Hank-1 and NK-YS, and an EBV-negative NK leukaemia cell line, NK-L, were treated with PI3K and Akt inhibitors, GA, and 17-AAG, and were subjected to apoptosis and cell viability assays, and immunoblot analysis. EBV-positive B-lymphoblastoid cell lines IM9 and LMP1-transfected IM9 (IM9-LMP1) were also included. Hank-1 and NK-YS cell viability was compromised and apoptosis was induced by LY294002 (PI3K inhibitor) or Akt inhibitor II. GA or 17-AAG administration resulted in the apoptosis of NKTL cells, accompanied by Akt and pAkt down-regulation, caspase 3 activation, and mitochondrial membrane potential disruption. The intrinsic level of pAkt was higher in EBV-positive NKTL cells than in EBV-negative NK-L, and GA or 17-AAG decreased the viability of NKTL cells more efficiently than NK-L. Moreover, IM9-LMP1 was more sensitive to Akt inhibitor II or HSP90 inhibitors than IM9. Importantly, GA showed little effect on the viability of normal peripheral NK cells as non-neoplastic counterparts for comparison. In conclusion, this study suggests that the PI3K/Akt pathway is frequently activated in EBV-positive NKTL and that therapeutic modalities based on targeting the PI3K/Akt pathway with HSP90 inhibitors could be useful for achieving NKTL control.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Apoptosis/drug effects , Benzoquinones/pharmacology , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Herpesvirus 4, Human/isolation & purification , Lactams, Macrocyclic/pharmacology , Lymphoma, Extranodal NK-T-Cell/pathology , Cell Survival , Down-Regulation/drug effects , Drug Evaluation, Preclinical , Humans , Lymphoma, B-Cell/metabolism , Lymphoma, B-Cell/pathology , Lymphoma, B-Cell/virology , Lymphoma, Extranodal NK-T-Cell/metabolism , Membrane Potential, Mitochondrial/physiology , Oncogene Protein v-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Tumor Cells, Cultured
9.
Biochem Soc Trans ; 34(Pt 5): 731-4, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17052184

ABSTRACT

The mammalian FoxO (forkhead box O) transcription factors FoxO1, FoxO3 and FoxO4 represent one of several effector arms of the PI3K (phosphoinositide 3-kinase)-Akt signalling network that has been linked to cancer, metabolism and aging. Specific roles of the FoxOs in the vascular cell types have been investigated to reveal that they play redundant yet critical roles in the proliferation and survival of ECs (endothelial cells). Somatic deletions of all FoxOs engendered progressive, widespread and highly penetrant haemangiomas associated with altered proliferative/survival dynamics of ECs in our genetic model. Related work by Akt-FoxO manipulation reported differentially regulated genes in ECs that may represent novel FoxO targets, controlling EC growth and morphogenesis and mediating many of the consequences of FoxO inactivation in the endothelium. Further studies on the action of these surrogate genes may provide important new insights into how the PI3K-Akt-FoxO pathway could be exploited clinically to treat vascular diseases and lead to the invention of novel therapeutic approaches. Here recent studies elucidating the role of FoxOs in the maintenance of vascular homoeostasis and supporting that the mammalian FoxO family serves essential roles in the maintenance of vascular stability and the suppression of aberrant vascular outgrowth are discussed.


Subject(s)
Blood Vessels/physiology , Forkhead Transcription Factors/physiology , Phosphatidylinositol 3-Kinases/metabolism , Animals , Cell Cycle , Forkhead Transcription Factors/deficiency , Forkhead Transcription Factors/genetics , Gene Deletion , Homeostasis , Humans , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/physiology , Proto-Oncogene Proteins c-akt/metabolism
10.
Histopathology ; 47(3): 281-91, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16115229

ABSTRACT

AIMS: To evaluate the different expression patterns and the prognostic significance of cell cycle regulatory molecules in diffuse large B-cell lymphomas (DLBCLs) of germinal centre (GC) and non-GC phenotypes. METHODS AND RESULTS: Tissue microarray slides composed of 126 extranodal and 88 nodal DLBCLs were immunostained for p16, p21, p27, p14 and p53. DLBCLs were classified into GC and non-GC phenotype according to the immunohistochemical expression of bcl-6, CD10, and MUM1. Aberrant expression of p53 was more frequent in the GC phenotype in nodal cases (P = 0.038), and the loss of p16, p21 and p14 expression was significantly more common in the non-GC phenotype (P = 0.004, P = 0.001, P < 0.001). Concurrent disruptions of the p16-Rb and p14-p53 pathways as represented by the immunoprofile of p16/p14/p53 (-/-/+) were associated with a poor prognosis in the GC phenotype [mean survival 31 months in the p16/p14/p53 (-/-/+) group versus 62 months in the other groups, P =0.0485]. CONCLUSIONS: The expression and prognostic implications of cell cycle regulatory molecules differ between GC and non-GC phenotypes in DLBCLs. The immunoprofile of p16/p14/p53 (-/-/+) within the GC phenotype of DLBCLs can be defined as a poor prognostic subgroup.


Subject(s)
Cell Cycle Proteins/biosynthesis , Germinal Center/pathology , Lymphoma, B-Cell/pathology , Lymphoma, Large B-Cell, Diffuse/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cyclin-Dependent Kinase Inhibitor p16/biosynthesis , Cyclin-Dependent Kinase Inhibitor p21 , Cyclin-Dependent Kinase Inhibitor p27 , Female , Germinal Center/chemistry , Humans , Immunohistochemistry , Lymphoma, B-Cell/metabolism , Lymphoma, Large B-Cell, Diffuse/metabolism , Male , Middle Aged , Prognosis , Survival Analysis , Tumor Suppressor Protein p14ARF/biosynthesis , Tumor Suppressor Protein p53/biosynthesis , Tumor Suppressor Proteins/biosynthesis
11.
J Clin Pathol ; 57(10): 1052-6, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15452159

ABSTRACT

BACKGROUND: Adult onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown aetiology, frequently accompanying multiple lymphadenopathy. It often mimics malignant lymphoma, and immunohistochemical and molecular studies are needed for definite diagnosis. AIMS: To aid in diagnosis and understand the pathogenesis of the disease by clarifying lymph node (LN) pathology in AOSD. METHODS: Thirteen biopsies (one follow up biopsy) and medical records of 12 patients were reviewed. Immunohistochemistry, polymerase chain reaction for T cell receptor gamma chain (TCRgamma) and immunoglobulin heavy chain gene rearrangement, and Epstein-Barr virus in situ hybridisation were performed. RESULTS: Histologically, LN lesions were classified into four patterns. The most common (six biopsies) showed paracortical hyperplasia, with prominent vascular proliferation, scattered large B/T immunoblasts, and infiltration by reactive lymphocytes and inflammatory cells. In the second pattern (two biopsies), paracortical hyperplasia was accompanied by massive sinus histiocytosis and S-100 positive histiocyte aggregates. The third pattern (three patients) showed an exuberant immunoblastic reaction, in the form of patchy/diffuse infiltration of large T immunoblasts with high mitotic activity, although clonal rearrangement of the TCRgamma gene was not detected. The fourth pattern showed distinct follicular hyperplasia (two cases). One patient with a follow up biopsy showed a pattern change from pronounced follicular hyperplasia to atypical paracortical hyperplasia. CONCLUSIONS: AOSD LN lesions show a dynamic histological spectrum, including atypical paracortical hyperplasia, burnt out histiocytic reaction, exuberant immunoblastic reaction, and follicular hyperplasia. During the course of disease, LN reactivity changes and mixed B and T cells are involved in the pathogenesis.


Subject(s)
Lymph Nodes/pathology , Still's Disease, Adult-Onset/pathology , Adolescent , Adult , Antigens, Viral/analysis , B-Lymphocytes/immunology , Female , Gene Rearrangement, B-Lymphocyte, Heavy Chain , Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/immunology , Humans , Immunohistochemistry/methods , In Situ Hybridization/methods , Lymph Nodes/immunology , Male , Polymerase Chain Reaction/methods , RNA, Viral/analysis , Still's Disease, Adult-Onset/immunology , T-Lymphocytes/immunology
12.
Science ; 294(5548): 1875-8, 2001 Nov 30.
Article in English | MEDLINE | ID: mdl-11729304

ABSTRACT

Upon cell activation, membrane phospholipids are metabolized into potent lysophospholipid (LP) mediators, such as sphingosine 1-phosphate and lysophosphatidic acid. LPs fulfill signaling roles in organisms as diverse as yeast and humans. The recent discovery of G protein-coupled receptors for LPs in higher eukaryotes, and their involvement in regulating diverse processes such as angiogenesis, cardiac development, neuronal survival, and immunity, has stimulated growing interest in these lipid mediators. LP receptor biology has generated insights into fundamental cellular mechanisms and may provide therapeutic targets for drug development.


Subject(s)
Lysophospholipids/metabolism , Receptors, Cell Surface/metabolism , Receptors, G-Protein-Coupled , Sphingosine/analogs & derivatives , Sphingosine/metabolism , Animals , Heterotrimeric GTP-Binding Proteins/antagonists & inhibitors , Heterotrimeric GTP-Binding Proteins/metabolism , Humans , Lysophospholipids/antagonists & inhibitors , Phylogeny , Receptors, Cell Surface/antagonists & inhibitors , Receptors, Lysophosphatidic Acid , Receptors, Lysophospholipid , Signal Transduction , Sphingosine/antagonists & inhibitors
13.
Mol Cell ; 8(3): 693-704, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11583630

ABSTRACT

The role of the protein kinase Akt in cell migration is incompletely understood. Here we show that sphingosine-1-phosphate (S1P)-induced endothelial cell migration requires the Akt-mediated phosphorylation of the G protein-coupled receptor (GPCR) EDG-1. Activated Akt binds to EDG-1 and phosphorylates the third intracellular loop at the T(236) residue. Transactivation of EDG-1 by Akt is not required for G(i)-dependent signaling but is indispensable for Rac activation, cortical actin assembly, and chemotaxis. Indeed, T236AEDG-1 mutant sequestered Akt and acted as a dominant-negative GPCR to inhibit S1P-induced Rac activation, chemotaxis, and angiogenesis. Transactivation of GPCRs by Akt may constitute a specificity switch to integrate rapid G protein-dependent signals into long-term cellular phenomena such as cell migration.


Subject(s)
Chemotaxis/physiology , Endothelium, Vascular/cytology , Immediate-Early Proteins/metabolism , Lysophospholipids , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins/metabolism , Receptors, G-Protein-Coupled , Signal Transduction/physiology , Actins/metabolism , Animals , Cell Line , Endothelium, Vascular/drug effects , Enzyme Activation/physiology , Humans , Models, Biological , Neovascularization, Physiologic/physiology , Phosphorylation , Protein Binding , Protein Structure, Tertiary , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins c-akt , Receptors, Cell Surface , Receptors, Lysophospholipid , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sphingosine/analogs & derivatives , Sphingosine/pharmacology , rac GTP-Binding Proteins/genetics , rac GTP-Binding Proteins/metabolism
14.
Br J Dermatol ; 145(1): 95-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11453914

ABSTRACT

BACKGROUND: There are racial differences in the prevalence and types of androgenetic alopecia (AGA). There have been several reports on the prevalence and types of AGA in the general population of caucasians, but few studies on Koreans with samples of sufficient numbers have been reported. OBJECTIVES: To obtain a more precise estimate of the prevalence and types of AGA in Korean men and women and to compare the results with those in caucasians. METHODS: The prevalence and types of AGA were analysed in 10,132 Koreans (5531 men and 4601 women) who had visited the Health Examination Centre at Kyung Hee University Hospital for regular health examinations between December 1997 and July 1999. To classify the degree of hair loss for each subject, the Norwood classification was used in men and the Ludwig classification in women. For AGA in men, 'female pattern' was added to the Norwood classification. RESULTS: In Korean men, the prevalence of AGA (Norwood III or above) at all ages was 14.1%. It increased steadily with advancing age, but was lower than that of caucasians: 2.3% in the third decade, 4.0% in the fourth decade, 10.8% in the fifth decade, 24.5% in the sixth decade, 34.3% in the seventh decade and 46.9% over 70 years. Type III vertex involvement was the most common type in the third decade to the seventh decade; over 70 years, type VI was most common. A 'female pattern' was observed in 11.1% of cases. In Korean women, the prevalence of AGA (Ludwig I or above) at all ages was 5.6%. It also increased steadily with advancing age: 0.2% in the third decade, 2.3% in the fourth decade, 3.8% in the fifth decade, 7.4% in the sixth decade, 11.7% in the seventh decade and 24.7% over 70 years. Grade I was the most common type up to the sixth decade; over 60 years, grade I and II were similar in prevalence. Grade III (total baldness) was not observed. A family history of baldness was present in 48.5% of men and 45.2% of women with AGA. CONCLUSIONS: The prevalence of AGA in Korean men and women was lower than that in caucasians, as recorded in the literature. Korean men tend to have more frontal hairline preservation and show a more 'female pattern' of hair thinning than caucasians. Therefore, 'female pattern' should be added to the classification of AGA.


Subject(s)
Alopecia/ethnology , Adult , Age Distribution , Aged , Alopecia/genetics , Alopecia/pathology , Female , Humans , Korea/epidemiology , Male , Middle Aged , Prevalence , Severity of Illness Index , Sex Factors
15.
Pediatr Dermatol ; 18(1): 31-3, 2001.
Article in English | MEDLINE | ID: mdl-11207967

ABSTRACT

We report periorbital congenital melanocytic nevus associated with ankyloblepharon in a 2-month-old boy. This unusual presentation may be explained by the assumption that the development of the congenital melanocytic nevus (CMN) in utero was related to the failure of normal eyelid separation, which occurs around the 20th week of gestation.


Subject(s)
Eyelids/abnormalities , Nevus, Pigmented/diagnosis , Skin Neoplasms/diagnosis , Diagnosis, Differential , Eyelids/surgery , Humans , Infant , Male , Nevus, Pigmented/complications , Nevus, Pigmented/congenital , Nevus, Pigmented/pathology , Skin Neoplasms/complications , Skin Neoplasms/congenital , Skin Neoplasms/pathology
16.
J Biol Chem ; 276(15): 11830-7, 2001 Apr 13.
Article in English | MEDLINE | ID: mdl-11150298

ABSTRACT

Sphingosine 1-phosphate (SPP), a platelet-derived bioactive lysophospholipid, is a regulator of angiogenesis. However, molecular mechanisms involved in SPP-induced angiogenic responses are not fully defined. Here we report the molecular mechanisms involved in SPP-induced human umbilical vein endothelial cell (HUVEC) adhesion and migration. SPP-induced HUVEC migration is potently inhibited by antisense phosphothioate oligonucleotides against EDG-1 as well as EDG-3 receptors. In addition, C3 exotoxin blocked SPP-induced cell attachment, spreading and migration on fibronectin-, vitronectin- and Matrigel-coated surfaces, suggesting that endothelial differentiation gene receptor signaling via the Rho pathway is critical for SPP-induced cell migration. Indeed, SPP induced Rho activation in an adherence-independent manner, whereas Rac activation was dispensible for cell attachment and focal contact formation. Interestingly, both EDG-1 and -3 receptors were required for Rho activation. Since integrins are critical for cell adhesion, migration, and angiogenesis, we examined the effects of blocking antibodies against alpha(v)beta(3), beta(1), or beta(3) integrins. SPP induced Rho-dependent integrin clustering into focal contact sites, which was essential for cell adhesion, spreading and migration. Blockage of alpha(v)beta(3)- or beta(1)-containing integrins inhibited SPP-induced HUVEC migration. Together our results suggest that endothelial differentiation gene receptor-mediated Rho signaling is required for the activation of integrin alpha(v)beta(3) as well as beta(1)-containing integrins, leading to the formation of initial focal contacts and endothelial cell migration.


Subject(s)
DNA-Binding Proteins/metabolism , Endothelium, Vascular/cytology , I-kappa B Proteins , Immediate-Early Proteins/metabolism , Integrin beta1/metabolism , Lysophospholipids , Receptors, Cell Surface , Receptors, G-Protein-Coupled , Receptors, Vitronectin/metabolism , Sphingosine/physiology , Base Sequence , Cells, Cultured , DNA Primers , Endothelium, Vascular/metabolism , Enzyme Activation , Fibrin/metabolism , GTP Phosphohydrolases/metabolism , Humans , Immunohistochemistry , NF-KappaB Inhibitor alpha , Receptors, Lysophospholipid , Sphingosine/analogs & derivatives
17.
J Biol Chem ; 275(36): 28173-9, 2000 Sep 08.
Article in English | MEDLINE | ID: mdl-10866999

ABSTRACT

The efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) is considered to be a result of their inhibitory effect on cyclooxygenase (COX) activity. Here, we report that flufenamic acid shows two opposing effects on COX-2 expression; it induces COX-2 expression in the colon cancer cell line (HT-29) and macrophage cell line (RAW 264.7); conversely, it inhibits tumor necrosis factor alpha (TNFalpha)- or lipopolysaccharide (LPS)-induced COX-2 expression. This inhibition correlates with the suppression of TNFalpha- or LPS-induced NFkappaB activation by flufenamic acid. The inhibitor of extracellular signal-regulated protein kinase, p38, or NFkappaB does not affect the NSAID-induced COX-2 expression. These results suggest that the NSAID-induced COX-2 expression is not mediated through activation of NFkappaB and mitogen-activated protein kinases. An activator of peroxisome proliferator-activated receptor gamma, 15-deoxy-Delta(12,14)-prostaglandin J(2), also induces COX-2 expression and inhibits TNFalpha-induced NFkappaB activation and COX-2 expression. Flufenamic acid and 15-deoxy-Delta(12,14)-prostaglandin J(2) also inhibit LPS-induced expression of inducible form of nitric-oxide synthase and interleukin-1alpha in RAW 264.7 cells. Together, these results indicate that the NSAIDs inhibit mitogen-induced COX-2 expression while they induce COX-2 expression. Furthermore, the results suggest that the anti-inflammatory effects of flufenamic acid and some other NSAIDs are due to their inhibitory action on the mitogen-induced expression of COX-2 and downstream markers of inflammation in addition to their inhibitory effect on COX enzyme activity.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Flufenamic Acid/pharmacology , Gene Expression Regulation, Enzymologic/drug effects , Isoenzymes/genetics , Lipopolysaccharides/pharmacology , Prostaglandin-Endoperoxide Synthases/genetics , Tumor Necrosis Factor-alpha/pharmacology , Adenocarcinoma , Animals , Colonic Neoplasms , Cyclooxygenase 2 , Enzyme Induction , Humans , Isoenzymes/biosynthesis , Lipopolysaccharides/antagonists & inhibitors , Macrophages/enzymology , Membrane Proteins , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type II , Prostaglandin D2/analogs & derivatives , Prostaglandin D2/pharmacology , Prostaglandin-Endoperoxide Synthases/biosynthesis , Receptors, Cytoplasmic and Nuclear/drug effects , Receptors, Cytoplasmic and Nuclear/physiology , Sulindac/analogs & derivatives , Sulindac/pharmacology , Transcription Factors/drug effects , Transcription Factors/physiology , Tumor Cells, Cultured , Tumor Necrosis Factor-alpha/antagonists & inhibitors
18.
J Dermatol ; 26(10): 677-81, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10554435

ABSTRACT

Pachyonchia congenita (PC) is an uncommon autosomal dominant genodermatosis affecting the nails and other ectodermal tissues. The most striking features are symmetrically thickened dysmorphic nails and hyperkeratotic skin lesions. We report a case of pachyonychia congenita in a 30-year-old male patient who had thickening and gray-brown discoloration of all nails and many nodules on his back and neck. He also had hyperkeratotic skin lesions on both feet. His tongue had irregularly-shaped, whitish plaques. Histology of these nodules revealed the characteristic features of steatocystoma multiplex. After treatment with oral retinoic acid, his hyperkeratotic skin lesions improved.


Subject(s)
Ectodermal Dysplasia/complications , Epidermal Cyst/complications , Keratoderma, Palmoplantar/complications , Leukoplakia, Oral/complications , Adult , Ectodermal Dysplasia/diagnosis , Ectodermal Dysplasia/genetics , Epidermal Cyst/diagnosis , Epidermal Cyst/genetics , Humans , Keratoderma, Palmoplantar/diagnosis , Keratoderma, Palmoplantar/genetics , Leukoplakia, Oral/diagnosis , Male , Nails, Malformed/complications , Nails, Malformed/diagnosis , Prognosis , Tretinoin/therapeutic use
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