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1.
Radiol Case Rep ; 19(3): 1106-1109, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38229607

ABSTRACT

Endovascular treatment of aneurysmal subarachnoid hemorrhage during pregnancy involves a risk of intraoperative radiation exposure to the fetus. The transradial approach does not require fluoroscopy of the maternal abdominopelvic region, which reduces fetal radiation exposure. We report a case of a female at 21 gestation weeks who developed subarachnoid hemorrhage due to a ruptured right posterior communicating artery aneurysm. The patient underwent balloon-assisted coil embolization via the transradial approach, which achieved aneurysmal obliteration with minimal fetal radiation exposure and without puncture site complications. The patient was free from neurological sequelae. Further, the patient delivered a healthy newborn through an elective cesarean section at 37 gestation weeks without any complications. The transradial approach allows endovascular treatment of ruptured intracranial aneurysms during pregnancy, with minimal risks of fetal radiation exposure.

2.
Sci Rep ; 13(1): 20746, 2023 11 25.
Article in English | MEDLINE | ID: mdl-38007576

ABSTRACT

Vicia sepium (bush vetch) is a perennial legume widely distributed throughout the Eurasian continent. However, its distribution in Japan is limited to Mt. Ibuki and small parts of central and southern Hokkaido. Therefore, each Japanese V. sepium lineage has been considered to have been introduced separately from Europe. Here, we examined whether the species was introduced or not on the basis of cpDNA sequences and genome-wide SNPs from Japanese and overseas samples. Both the cpDNA haplotype network and the nuclear DNA phylogenetic tree showed that Japanese V. sepium is monophyletic. Furthermore, although the nuclear DNA phylogenetic tree also showed that each lineage is clearly monophyletic, genetic admixture of the genetic cluster dominated in the Hokkaido lineage was also detected in the Mt. Ibuki lineage. Population divergence analysis showed that the two lineages diverged during the last glacial period. The Mt. Ibuki lineage showed a sudden population decline 300-400 years ago, indicating that some anthropogenic activity might be involved, while the Hokkaido lineage showed a gradual population decline from 5000 years ago. Consequently, these two lineages show low current genetic diversity compared with overseas lineages. These results show that the Japanese V. sepium is not introduced but is native.


Subject(s)
Vicia , Animals , Phylogeny , Japan , Vicia/genetics , DNA, Chloroplast , Haplotypes , Demography , Genetic Variation , DNA, Mitochondrial/genetics
3.
J Artif Organs ; 25(4): 305-313, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35254539

ABSTRACT

Two equations have been developed from multi-frequency measurements of blood impedance Zb for a simultaneous electrical online estimation of changes in blood hematocrit ΔH [%] and temperatures ΔT [K] in cardiopulmonary bypass (CPB). Zb of fixed blood volumes at varying H and T were measured by an impedance analyzer and changes in blood conductivity σb and relative permittivity εb computed. Correlation analysis were based on changes in σb with H or T at f = 1 MHz while H and T equations were developed by correlating changes in εb with H and T at dual frequencies of f = 1 MHz and f = 10 MHz which best capture blood plasma Zp and red blood cell cytoplasm Zcyt impedances respectively. Results show high correlations between σb and H (R2 = 0.987) or σb and T (R2 = 0.9959) indicating dependence of the electrical parameters of blood on its H and T. Based on computed εb, changes in blood hematocrit ΔH and temperature ΔT at a given time t are estimated as ΔH(t) = 1.7298Δεb (f = 1 MHz) - 1.0669Δεb (f = 10 MHz) and ΔT(t) = -2.186Δεb (f = 1 MHz) + 2.13Δεb (f = 10 MHz). When applied to a CPB during a canine mitral valve plasty, ΔH and ΔT had correlations of R2 = 0.9992 and R2 = 0.966 against H and T respectively as measured by conventional devices.


Subject(s)
Cardiopulmonary Bypass , Animals , Dogs , Cardiopulmonary Bypass/methods , Hematocrit , Temperature , Electric Impedance
4.
Biochemistry ; 61(7): 523-534, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35230084

ABSTRACT

Heme binds selectively to the 3'-terminal G-quartet of all parallel G-quadruplex DNAs to form stable heme-DNA complexes. Interestingly, the heme-DNA complexes exhibit various spectroscopic and functional properties similar to those of hemoproteins. Since the nature of the axial ligands is crucial in determining the physicochemical properties of heme, identification and characterization of the axial ligands in a heme-DNA complex are essential to elucidate the structure-function relationship in the complex. NMR studies of a complex possessing a low-spin ferric heme with a water molecule (H2O) and cyanide ion (CN-) as the axial ligands allowed detailed characterization of the physicochemical nature of the axial H2O ligand. We found that the in-plane asymmetry of the heme electronic structure of the complex is not largely affected by the axial H2O coordination, indicating that the H2O confined in the hydrophobic interface between the heme and G-quartet planes of the complex rotates about the coordination bond with respect to the heme. The effect of the hydrogen(H)/deuterium(D) isotope replacement of the axial H2O on the heme electronic structure was manifested in the isotope shifts of paramagnetically shifted heme methyl proton signals of the complex in such a manner that three resolved peaks associated with axial H2O, HDO, and D2O were observed for each of the heme methyl proton signals. These findings provide not only the basis for an understanding of the nature of the unique axial H2O but also an insight into the molecular mechanism responsible for the control of the heme reactivity in the heme-DNA complex.


Subject(s)
G-Quadruplexes , Hemeproteins , DNA/chemistry , Heme/chemistry , Ligands
5.
Nihon Hinyokika Gakkai Zasshi ; 113(2): 73-77, 2022.
Article in Japanese | MEDLINE | ID: mdl-37081656

ABSTRACT

We report a case of open surgical hemostasis following transarterial embolization (TAE) that failed to stabilize the hemodynamics for renal injury after extracorporeal shock wave lithotripsy (ESWL). A 48-year-old man presented with severe left renal colic pain 1 day after ESWL for a left renal stone. Computed tomography revealed arterial bleeding from the lower pole of the left kidney and retroperitoneal hematoma. TAE was successfully performed for the lower poler bleeding. However, we were unable to complete the procedure for bleeding from an aberrant artery to the lower pole of the kidney that was supplied directly from the aorta. Therefore, an emergency laparotomy was performed and the injury in the aberrant artery was manually ligated. Hemostasis was obtained after the direct surgical ligation and he had a good postoperative recovery. Open surgical hemostasis is a treatment modality that should be considered following TAE that fails to control arterial bleeding after ESWL.


Subject(s)
Embolization, Therapeutic , Kidney Calculi , Lithotripsy , Male , Humans , Middle Aged , Hemostasis, Surgical , Kidney , Kidney Calculi/surgery , Lithotripsy/adverse effects , Lithotripsy/methods
6.
NMC Case Rep J ; 8(1): 247-252, 2021.
Article in English | MEDLINE | ID: mdl-35079471

ABSTRACT

Tremor associated with encephalitis is usually transient and rarely becomes chronic and refractory. Treatment for such tremor using deep brain stimulation (DBS) has not yet been reported. We report an uncommon case of chronic tremor after encephalitis of unknown etiology and its outcome treated with thalamic DBS. A 47-year-old man presented with a 6-month history of medically refractory tremor after non-infectious and probable autoimmune encephalitis. The patient showed an atypical mixture of resting, postural, kinetic, and intention tremor. The tremor significantly disabled the patient's activities of daily life (ADL). The patient underwent bilateral thalamic DBS surgery. DBS leads were placed to cross the border between the ventralis oralis posterior (Vop) nucleus and ventralis intermedius (Vim) nucleus of the thalamus. Stimulation of both the Vop and Vim using the bipolar contacts controlled the mixed occurrence of tremor. The ADL and performance scores on The Essential Tremor Rating Assessment Scale (TETRAS) improved from 47 to 0 and from 44 to 9, respectively. The therapeutic effects have lasted for 24 months. Administration of combined Vop and Vim DBS may control uncommon tremor of atypical etiology and phenomenology.

7.
Polymers (Basel) ; 12(1)2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31952267

ABSTRACT

Cell Separation is important in various biomedical fields. We have prepared gold nanoparticle (AuNP)-embedded collagen gels as a visible-light-responsive cell scaffold in which photoinduced single cell detachment occurs through local thermal denaturation of the collagen gel via the photothermal effect of AuNP. Physicochemical properties of collagen materials depend on the origin of the collagen and the presence of telopeptides. In this study, we prepared various AuNP-embedded collagen gels by using different collagen materials with and without the telopeptides to compare their thermal denaturation properties and photoinduced single cell detachment behaviors. Cellmatrix type I-C without telopeptides exhibited a lower denaturation temperature than Cellmatrix type I-A and Atelocell IAC, as examined by Fourier transform infrared (FTIR) spectroscopy, rheological analysis, and sol-gel transition observation. Three-dimensional (3D) laser microscopic imaging revealed that collagen fibers shrank in Cellmatrix type I-A upon heating, but collagen fibers disappeared in Cellmatrix type I-C upon heating. Cells cultured on the Cellmatrix type I-C-based AuNP-embedded collagen gel detached with shorter photoirradiation than on the Cellmatrix type I-A-based AuNP-embedded collagen gel, suggesting that collagen gels without telopeptides are suitable for a photoinduced single cell detachment system.

8.
Sports (Basel) ; 7(1)2019 Jan 18.
Article in English | MEDLINE | ID: mdl-30669254

ABSTRACT

Stair climbing provides a feasible opportunity for increasing physical activity (PA) in daily living. The purpose of this study was to examine the daily walking and stair-climbing steps among healthy older adults (age: 74.0 ± 4.9 years; Body Mass Index (BMI): 22.3 ± 2.5 kg/m²). Participants (34 females and 15 males) attended a weekly 6-month community-based PA program. During the entire program period, daily walking and stair-climbing steps were recorded using a pedometer (Omron, HJA-403C, Kyoto, Japan). Before and after the 6-month program, height, body weight and leg muscle strength were assessed. After the 6-month program, the mean walking and stair-climbing steps in both women and men increased significantly (p ≤ 0.01). Daily stair-climbing steps increased about 36 steps in women and 47 steps in men. At the end of 6 months, only male participants had significant correlation between the number of stair steps and leg muscle strength (r = 0.428, p = 0.037). This study reported that healthy older adults attending the community-based PA program had regular stair-climbing steps during daily living. Promoting stair climbing as an exercise routine was feasible to increase their walking and stair-climbing steps.

9.
ACS Biomater Sci Eng ; 5(11): 5698-5704, 2019 Nov 11.
Article in English | MEDLINE | ID: mdl-33405701

ABSTRACT

Ovalbumin (OVA) is the most abundant protein in egg whites that is unnecessary in the egg yolk-based food industry. The development of OVA-based functional materials is of great interest. Collagen is a major component of the extracellular matrix. In this study, an OVA fragment, the OVA secretory signal peptide (OVA SP), was loaded in collagen gels, which were used as a cell scaffold for various types of cells. We examined the effect of OVA SP loaded in collagen gels to cell properties. The peptide was initially bound to the collagen fibers and then released from the gel. Our results indicate that the released OVA SP suppressed the integrin-mediated cell adhesion and focal adhesion formation. However, the adhesion of NIH3T3 cells was not suppressed by treatment with a chelating agent and an anti-ß1 antibody. Our results suggest that OVA SP nonspecifically interacts with cell surface proteins. The adhesion of various cell types on collagen gels were changed by the addition of OVA SP, depending on their integrin expression pattern. Additionally, the differentiation of MC3T3-E1 osteoblastic cells was promoted on the OVA SP-loaded collagen gels. This suggests that OVA SP may modulate both the differentiation and the adhesion of cells cultured on the collagen gels.

10.
J Exp Bot ; 68(13): 3441-3456, 2017 06 15.
Article in English | MEDLINE | ID: mdl-28633373

ABSTRACT

The direction of auxin transport changes in gravistimulated roots, causing auxin accumulation in the lower side of horizontally reoriented roots. This study found that auxin was similarly involved in hydrotropism and gravitropism in rice and pea roots, but hydrotropism in Lotus japonicus roots was independent of both auxin transport and response. Application of either auxin transport inhibitors or an auxin response inhibitor decreased both hydrotropism and gravitropism in rice roots, and reduced hydrotropism in pea roots. However, Lotus roots treated with these inhibitors showed reduced gravitropism but an unaltered or an enhanced hydrotropic response. Inhibiting auxin biosynthesis substantially reduced both tropisms in rice and Lotus roots. Removing the final 0.2 mm (including the root cap) from the root tip inhibited gravitropism but not hydrotropism in rice seedling roots. These results suggested that modes of auxin involvement in hydrotropism differed between plant species. In rice roots, although auxin transport and responses were required for both gravitropism and hydrotropism, the root cap was involved in the auxin regulation of gravitropism but not hydrotropism. Hydrotropism in Lotus roots, however, may be regulated by a novel mechanism that is independent of both auxin transport and the TIR1/AFBs auxin response pathway.


Subject(s)
Gravitropism , Indoleacetic Acids/metabolism , Lotus/physiology , Oryza/physiology , Pisum sativum/physiology , Biological Transport , Plant Roots/physiology , Seedlings/physiology , Species Specificity
11.
Macromol Biosci ; 17(5)2017 05.
Article in English | MEDLINE | ID: mdl-27910289

ABSTRACT

Cell sorting is important for cell biology and regenerative medicine. A visible light-responsive cell scaffold is produced using gold nanoparticles and collagen gel. Various kinds of cells are cultured on the visible light-responsive cell scaffold, and the target cells are selectively detached by photoirradiation without any cytotoxicity. This is a new image-guided cell sorting system.


Subject(s)
Cell Adhesion/radiation effects , Collagen/chemistry , Gold/chemistry , Lasers , Metal Nanoparticles/chemistry , Animals , Cells, Cultured , Dogs , Gels , Humans
12.
Stem Cells Dev ; 25(11): 815-25, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27059007

ABSTRACT

Cell replacement therapy holds great promise for Parkinson's disease (PD), but residual undifferentiated cells and immature neural progenitors in the therapy may cause tumor formation. Although cell sorting could effectively exclude these proliferative cells, from the viewpoint of clinical application, there exists no adequate coping strategy in the case of their contamination. In this study, we analyzed a component of proliferative cells in the grafts of human-induced pluripotent stem cell-derived neural progenitors and investigated the effect of radiation therapy on tumor formation. In our differentiating protocol, analyses of neural progenitors (day 19) revealed that the proliferating cells expressed early neural markers (SOX1, PAX6) or a dopaminergic neuron progenitor marker (FOXA2). When grafted into the rat striatum, these immature neurons gradually became postmitotic in the brain, and the rosette structures disappeared at 14 weeks. However, at 4-8 weeks, the SOX1(+)PAX6(+) cells formed rosette structures in the grafts, suggesting their tumorigenic potential. Therefore, to develop a fail-safe therapy against tumor formation, we investigated the effect of radiation therapy. At 4 weeks posttransplantation, when KI67(+) cells comprised the highest ratio, radiation therapy with (137)Cs Gammacell Exactor for tumor-bearing immunodeficient rats showed a significant decrease in graft volume and percentage of SOX1(+)KI67(+) cells in the graft, thus demonstrating the preventive effect of gamma-ray irradiation against tumorigenicity. These results give us critical criteria for the safety of future cell replacement therapy for PD.


Subject(s)
Carcinogenesis/pathology , Carcinogenesis/radiation effects , Gamma Rays , Induced Pluripotent Stem Cells/pathology , Neural Stem Cells/pathology , Cell Differentiation/radiation effects , Cell Line , Cell Proliferation/radiation effects , Dopaminergic Neurons/cytology , Dopaminergic Neurons/radiation effects , Humans , Immunohistochemistry , Induced Pluripotent Stem Cells/radiation effects , Mesencephalon/cytology , Neural Stem Cells/radiation effects , Spheroids, Cellular/cytology , Spheroids, Cellular/radiation effects , Stem Cell Transplantation
13.
Cancer Med ; 3(2): 349-61, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24515895

ABSTRACT

Treatment of advanced oral squamous cell carcinoma (OSCC) requires the integration of multimodal approaches. The aim of this study was to identify predictors of tumor sensitivity to preoperative radiotherapy/chemotherapy for OSCC in order to allow oncologists to determine optimum therapeutic strategies without the associated adverse effects. Here, the protein expression profiles of formalin-fixed paraffin-embedded (FFPE) tissue samples from 18 OSCC patients, termed learning cases, who received preoperative chemotherapy and/or radiotherapy followed by surgery were analyzed by quantitative proteomics and validated by immunohistochemistry in 68 test cases as well as in the 18 learning cases. We identified galectin-7 as a potential predictive marker of chemotherapy and/or radiotherapy resistance, and the sensitivity and specificity of the galectin-7 prediction score (G7PS) in predicting this resistance was of 96.0% and 39.5%, respectively, in the 68 test cases. The cumulative 5-year disease-specific survival rate was 75.2% in patients with resistant prediction using G7PS and 100% in patients with sensitive prediction. In vitro overexpression of galectin-7 significantly decreased cell viability in OSCC cell line. Therefore, our findings suggest that galectin-7 is a potential predictive marker of chemotherapy and/or radiotherapy resistance in patients with OSCC.


Subject(s)
Biomarkers, Tumor/analysis , Carcinoma, Squamous Cell/chemistry , Galectins/analysis , Mouth Neoplasms/chemistry , Aged , Aged, 80 and over , Biomarkers, Tumor/biosynthesis , Biopsy , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/radiotherapy , Chromatography, Liquid , Female , Galectins/biosynthesis , Humans , Male , Middle Aged , Mouth Neoplasms/drug therapy , Mouth Neoplasms/metabolism , Mouth Neoplasms/radiotherapy , Predictive Value of Tests , Proteomics/methods , Retrospective Studies , Tandem Mass Spectrometry
14.
Stem Cells Dev ; 22(3): 374-82, 2013 Feb 01.
Article in English | MEDLINE | ID: mdl-23020188

ABSTRACT

Although transplanted pluripotent stem cell-derived neurons can contribute to functional recovery in animal models of Parkinson's disease, the risk of tumor formation hinders clinical applications of this approach. Removing undifferentiated cells from the donor population is critical to reduce tumorigenesis. Moreover, immature neural progenitors in transplants can proliferate unpredictably, resulting in neural overgrowth and long-term risks of compressing the surrounding host tissue. Because Notch signaling plays a role in maintaining the multipotency and proliferative capacity of neural progenitors, we used γ-secretase inhibitors (GSIs) to dampen Notch signaling in human-induced pluripotent stem cell-derived neural progenitors before transplantation and examined the effects on the growth of proliferative grafts. We observed a marked reduction in the percentage of dividing cells and increased neuronal maturation in GSI-treated samples in vitro. Next, grafts were transplanted into the striata of nonobese diabetic/severe combined immune deficiency mice. Histological analyses performed 8 weeks after the operation showed that grafts pretreated with GSIs--N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester or compound E--were significantly smaller than control samples. Immunohistologic analyses revealed that briefly treating the donor population with GSIs not only reduced the graft volume, but also altered the composition of the graft; control grafts showed neural overgrowth with numerous PAX6+ and Ki67+ neural rosettes, whereas GSI-treated samples developed into mature neuronal grafts containing primarily Tubß3+ cells. These results suggest that pretreating potentially proliferative progenitors with GSIs may improve the safety of cell replacement therapies using pluripotent stem cells.


Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Cell Proliferation/drug effects , Cell Transformation, Neoplastic/drug effects , Induced Pluripotent Stem Cells/physiology , Neural Stem Cells/drug effects , Animals , Benzodiazepinones/pharmacology , Cell Differentiation , Cell Line , Dipeptides/pharmacology , Dopaminergic Neurons/drug effects , Dopaminergic Neurons/enzymology , Dopaminergic Neurons/transplantation , Humans , Mice , Mice, Inbred NOD , Mice, SCID , Neural Stem Cells/enzymology , Neural Stem Cells/transplantation
15.
Water Environ Res ; 84(2): 120-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22515061

ABSTRACT

In this study, a method for removing water from biosolids that uses dimethyl ether (DME) as an extractant was considered. This study evaluates the applicability of the DME dewatering method to biosolid cakes by using a DME flow-type experimental apparatus. It was found that a high dewatering ratio is clearly achieved by increasing the liquefied DME/biosolid ratio and lowering the liquefied DME linear velocity. As the liquefied DME/biosolid ratio was increased, the carbon content in dewatered biosolid showed a slight decrease and the TOC concentration in separated liquid increased significantly. Finally, the input energy Es to remove 1 kg of water from the biosolid cake, using both the DME dewatering method and the conventional drying method was estimated. The calculation shows that Es for the DME dewatering process is approximately a third of Es for the conventional thermal drying process.


Subject(s)
Methyl Ethers/chemistry , Sewage/chemistry , Waste Disposal, Fluid/methods , Water/chemistry
16.
Odontology ; 100(2): 156-63, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21607591

ABSTRACT

Overexpression of epidermal growth factor receptor (EGFR) is associated with resistance to chemotherapy and radiotherapy, advanced tumor stage, invasion, metastasis and poor prognosis in malignant tumors. EGFR, therefore, has been an attractive molecular target for chemotherapy. However, the results of clinical studies using inhibitors of its kinase activity have not been promising because the response rates were at most 20%. Sodium-glucose co-transporter 1 (SGLT1) is a membrane protein that mediates the transport of glucose across cellular membranes. EGFR physically associates with and stabilizes SGLT1 to promote glucose uptake into cancer cells through a kinase-independent process. The purpose of this study was to investigate the coexpression of SGLT1 and EGFR and its relationships with clinicopathological features in oral squamous cell carcinoma (OSCC). SGLT1 and EGFR were detected in all OSCC cell lines, and the expression levels of SGLT1 were significantly correlated with those of EGFR. Pearson product-moment correlation coefficient of SGLT1 and EGFR was 0.89 (P = 0.016). The immunohistochemical study using the surgical specimens in 52 patients with tongue SCC also showed a significant correlation between SGLT1 and EGFR. Moreover, SGLT1/EGFR expression was inversely related to tumor differentiation among the 5 clinicopathological factors (P = 0.004). SGLT1/EGFR coexpression might be required in the de-differentiation of OSCC, but further study is needed to clarify the implication of these proteins in the manifestation of malignancy and clinical significance.


Subject(s)
Carcinoma, Squamous Cell/pathology , Cell Transformation, Neoplastic/pathology , ErbB Receptors/analysis , Mouth Neoplasms/pathology , Sodium-Glucose Transporter 1/analysis , Adult , Aged , Aged, 80 and over , Blotting, Western , Carcinoma, Squamous Cell/secondary , Cell Differentiation/physiology , Cell Line, Tumor , ErbB Receptors/physiology , Female , HeLa Cells , Humans , Immunohistochemistry , Lymphatic Metastasis/pathology , Male , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Neoplasm Staging , Protein Processing, Post-Translational/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sodium-Glucose Transporter 1/physiology , Tongue Neoplasms/pathology , Transfection , Up-Regulation , Young Adult
17.
J Oral Pathol Med ; 39(7): 525-32, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20040024

ABSTRACT

BACKGROUND: The Fas-associated death domain-containing protein, FADD, is an adaptor for relaying apoptotic signals. However, recent studies have shown that FADD also plays an important role in the growth and regulation of the cell cycle. The purpose of this study was to elucidate the role of FADD in oral squamous cell carcinoma (SCC). METHODS: The DNA amplification of FADD from 30 samples of tongue SCC was analyzed using real-time PCR and the protein expression of FADD from 60 samples of tongue SCC was analyzed using immunohistochemistry. RESULTS: The DNA amplifications of FADD were observed in 13 cases (44.3%) and were significantly correlated with the histopathological differentiation grade of SCCs (P = 0.009). FADD expression levels compared with the matched adjacent epithelium increased significantly (P = 0.000). Additionally, the positive expressions of FADD were significantly correlated with lymph node metastasis of SCCs (P = 0.029) and the 5-year disease-specific survival rates (P = 0.049). A positive association between FADD expression level and the histopathological differentiation grade was found to be limited to T1 SCCs (P = 0.019). DNA amplification was moderately correlated (correlation coefficient = 0.406, P = 0.026) with expression of FADD in 30 samples of tongue SCC. CONCLUSION: In tongue SCCs, the expression of FADD was higher when compared with that of adjacent areas, which might be determined via genomic amplification in 11q13.3. Thus, SCC cells with the expression of FADD are possibly more likely to become metastatic and to worsen survival rates.


Subject(s)
Carcinoma, Squamous Cell/genetics , Fas-Associated Death Domain Protein/genetics , Gene Amplification/genetics , Gene Expression Regulation, Neoplastic/genetics , Tongue Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Apoptosis/genetics , Biomarkers, Tumor/analysis , Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/pathology , Cell Cycle/genetics , Cell Line, Tumor , Chromosomes, Human, Pair 11/genetics , Epithelium/pathology , Female , Humans , Immunohistochemistry , Lymphatic Metastasis/genetics , Lymphatic Metastasis/pathology , Male , Middle Aged , Neoplasm Staging , Polymerase Chain Reaction/methods , Survival Rate , Tongue/pathology , Tongue Neoplasms/pathology
18.
Biochem Biophys Res Commun ; 364(4): 1050-5, 2007 Dec 28.
Article in English | MEDLINE | ID: mdl-17976373

ABSTRACT

Cell cycle-dependent transcriptional repression of the E2F1 and B-myb promoters is mediated through E2F-binding sites and adjacent corepressor site (cell cycle gene homology region (CHR)/downstream repression site (DRS)). Here, we show that a factor binding to the B-myb CHR is co-purified with E2F DNA-binding activity, and coimmunoprecipitated with components of E2F/Rb-family repressor complexes, E2F4 and retinoblastoma (Rb) family proteins. In spite of structural and functional similarities, however, the E2F1 and B-myb CHRs exhibited distinct factor-binding specificities. Furthermore, substitution of E2F1 CHR with the B-myb CHR in the E2F1 promoter revealed that the B-myb CHR was unable to repress the E2F1 promoter completely in the G0 phase. These results suggest that transcriptional repression of the E2F1 and B-myb promoters is mediated by physical interaction of E2F/Rb-family repressor complexes with promoter-specific corepressors.


Subject(s)
E2F Transcription Factors/metabolism , Fibroblasts/metabolism , Repressor Proteins/metabolism , Retinoblastoma Protein/metabolism , Transcriptional Activation/physiology , Animals , Binding Sites , Cell Line , Mice , Protein Binding
19.
Nat Cell Biol ; 8(12): 1359-68, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17115032

ABSTRACT

The proliferating cell nuclear antigen (PCNA) is an essential protein for DNA replication and damage repair. How its function is controlled remains an important question. Here, we show that the chromatin-bound PCNA protein is phosphorylated on Tyr 211, which is required for maintaining its function on chromatin and is dependent on the tyrosine kinase activity of EGF receptor (EGFR) in the nucleus. Phosphorylation on Tyr 211 by EGFR stabilizes chromatin-bound PCNA protein and associated functions. Consistently, increased PCNA Tyr 211 phosphorylation coincides with pronounced cell proliferation, and is better correlated with poor survival of breast cancer patients, as well as nuclear EGFR in tumours, than is the total PCNA level. These results identify a novel nuclear mechanism linking tyrosine kinase receptor function with the regulation of the PCNA sliding clamp.


Subject(s)
Phosphotyrosine/metabolism , Proliferating Cell Nuclear Antigen/chemistry , Proliferating Cell Nuclear Antigen/metabolism , Cell Nucleus/metabolism , Cell Proliferation , Chromatin/metabolism , DNA Repair , DNA Replication , ErbB Receptors/metabolism , HeLa Cells , Humans , Phosphorylation , Protein Binding , Thermodynamics
20.
Mol Carcinog ; 45(1): 10-7, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16299810

ABSTRACT

Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is frequently over-expressed in human cancers and is associated with tumorigenesis, and increased tumor proliferation and progression. Also found in breast tumors with high levels is B-Myb, a transcription factor whose expression is activated by E2F1/3 at the late G1 phase and the level is sustained through the S phase. Recent reports suggest a casual correlation between EGFR and B-Myb expression in primary breast carcinomas. However, the mechanism for such co-expression remains un-investigated. Here, we report that EGFR is important for B-Myb expression and the underlying mechanism involves cooperated effects from EGFR and E2F1. EGF stimulation and forced expression of EGFR significantly increase B-Myb gene activity and such increase occurs in the G1 phase. EGF-induced B-Myb expression was not significantly suppressed following inhibition of PI-3K and ERK, two major EGFR downstream pathways. In contrast, we observed EGF-induced in vivo association of nuclear EGFR to the B-Myb promoter and the association is only detected at the G1/S phase and is abolished by EGFR kinase inhibitor. As EGFR lacks DNA-binding domain but contains transactivational activity and E2F1 activates B-Myb expression in the G1/S phase, we further reasoned that nuclear EGFR might cooperate with E2F1 leading to activation of B-Myb. Indeed, we found that EGFR co-immunoprecipitated with E2F1 in an EGF-dependent manner and that EGF activated in vivo binding of E2F1 to the B-Myb promoter. Consistently, forced expression of both EGFR and E2F1 in EGFR-null CHO cells greatly enhanced B-Myb promoter activity, compared to the vector control and expression of EGFR or E2F1 alone. Promoter mutagenesis studies showed that EGF-induced activation of B-Myb promoter required both E2F and EGFR target sites. In summary, our data suggest that deregulated EGFR signaling pathway facilitate tumor cell proliferation partly via EGFR interaction with E2F1 and subsequent activation of B-Myb gene expression.


Subject(s)
Cell Cycle Proteins/genetics , DNA-Binding Proteins/genetics , E2F1 Transcription Factor/physiology , ErbB Receptors/physiology , Gene Expression Regulation/physiology , Trans-Activators/genetics , Animals , Base Sequence , Cell Cycle , Cell Line , Chromatin Immunoprecipitation , Cricetinae , DNA Primers , Humans , Mice , Promoter Regions, Genetic
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