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1.
Sci Adv ; 6(19): eaat9488, 2020 May.
Article in English | MEDLINE | ID: mdl-32494692

ABSTRACT

The existence of nontrivial Berry phases associated with two inequivalent valleys in graphene provides interesting opportunities for investigating the valley-projected topological states. Examples of such studies include observation of anomalous quantum Hall effect in monolayer graphene, demonstration of topological zero modes in "molecular graphene" assembled by scanning tunneling microscopy, and detection of topological valley transport either in graphene superlattices or at bilayer graphene domain walls. However, all aforementioned experiments involved nonscalable approaches of either mechanically exfoliated flakes or atom-by-atom constructions. Here, we report an approach to manipulating the topological states in monolayer graphene via nanoscale strain engineering at room temperature. By placing strain-free monolayer graphene on architected nanostructures to induce global inversion symmetry breaking, we demonstrate the development of giant pseudo-magnetic fields (up to ~800 T), valley polarization, and periodic one-dimensional topological channels for protected propagation of chiral modes in strained graphene, thus paving a pathway toward scalable graphene-based valleytronics.

2.
Nanoscale ; 9(48): 19227-19235, 2017 Dec 14.
Article in English | MEDLINE | ID: mdl-29188264

ABSTRACT

We report the long-term stability of water-sensitive hybrid perovskites CH3NH3PbI3 that were protected with monolayer graphene. This successful passivation was enabled by our development of a new water-free and polymer-free graphene transfer method. Monolayer graphene samples grown by plasma-enhanced chemical vapor deposition and transferred onto different substrates with the water/polymer-free method were found to preserve their high-quality characteristics after the transfer, as manifested by the studies of Raman, X-ray and ultraviolet photoemission spectroscopy (XPS and UPS), optical absorption, and sheet resistance. Additionally, XPS, UPS and optical absorption studies of fully graphene-covered CH3NH3PbI3 thin films showed spectral invariance even after 3 months, which was in sharp contrast to the drastic spectral changes after merely one week in control CH3NH3PbI3 samples without graphene protection. This successful demonstration of the graphene-enabled passivation and long-term stability of CH3NH3PbI3 thin films therefore opens up a new pathway towards realistic photovoltaic applications of hybrid perovskites.

3.
Public Health ; 138: 50-6, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27091437

ABSTRACT

OBJECTIVES: Current guidelines support the use of screening for early detection in breast, prostate, colorectal and cervical cancer. The purpose of this study was to evaluate whether insurance status predicts for more advanced disease in these four currently screened cancers. STUDY DESIGN: The Surveillance, Epidemiology, and End Results (SEER) database was queried for breast, prostate, colorectal and cervix in patients aged 18-64 years. The database was queried from 2007 to 2011, with 425,614 patients with known insurance status included. METHODS: Multinomial logistic regression was used to evaluate insurance status and cancer presentation. RESULTS: Under multivariate analysis for breast cancer, uninsured patients more often had invasive disease (odds ratio [OR]: 1.55), T- (OR: 2.00), N- (OR: 1.59) stage, and metastatic disease (OR: 3.48), and were more often high-grade (OR: 1.21). For prostate cancer, uninsured patients again presented more commonly with higher T-stage (OR: 1.45), nodal (OR: 2.90) and metastatic (OR: 4.98) disease, in addition to higher prostate-specific antigen (OR: 2.85) and Gleason score (OR: 1.65). Colorectal cancer had similar findings with uninsured individuals presenting with more invasive disease (OR: 1.78), higher T (OR: 1.86), N (OR: 1.22), and M (OR: 1.58) stage, in addition to higher carcinoembryonic antigen levels (OR: 1.66). Similar results were seen for cervical cancer with uninsured having higher T (OR: 2.03), N (OR: 1.21), and M (OR: 1.45) stage. CONCLUSION: In the four cancers detected by screening exams, those without health insurance present with more advanced disease, with higher stage and grade, and more elevated tumour markers.


Subject(s)
Early Detection of Cancer , Health Status Disparities , Insurance Coverage/statistics & numerical data , Insurance, Health/statistics & numerical data , Neoplasms/pathology , Adolescent , Adult , Breast Neoplasms/pathology , Colorectal Neoplasms/pathology , Databases, Factual , Female , Humans , Male , Medically Uninsured/statistics & numerical data , Middle Aged , Neoplasm Staging , Prostatic Neoplasms/pathology , United States , Uterine Cervical Neoplasms/pathology , Young Adult
4.
Ann Oncol ; 27(5): 818-27, 2016 05.
Article in English | MEDLINE | ID: mdl-26861597

ABSTRACT

BACKGROUND: Following neoadjuvant chemotherapy (NAC), the optimal strategies for postmastectomy radiotherapy (PMRT) and regional nodal irradiation (RNI) after breast-conserving surgery (BCS) are controversial. In this analysis, we evaluate the impact of these radiotherapy (RT) approaches for women with clinically node-positive breast cancer treated with NAC in the National Cancer Database (NCDB). PATIENTS AND METHODS: Women with cT1-3 cN1 M0 breast cancer treated with NAC were divided into four cohorts by surgery [Mastectomy (Mast) versus BCS] and post-chemotherapy pathologic nodal status (ypN0 versus ypN+). Overall survival (OS) was estimated using the Kaplan-Meier method and RT approaches were analyzed using the log-rank test, multivariate Cox models, and propensity score-matched analyses. RESULTS: From 2003 to 2011, 15 315 cases were identified including 3040 Mast-ypN0, 7243 Mast-ypN+, 2070 BCS-ypN0, and 2962 BCS-ypN+ patients. On univariate analysis, PMRT was associated with improved OS for both Mast-ypN0 (P = 0.019) and Mast-ypN+ (P < 0.001) patients. On multivariate analyses adjusted for factors including age, comorbidity score, cT stage, in-breast pathologic complete response, axillary surgery, ypN stage, estrogen receptor status and hormone therapy, PMRT remained independently associated with improved OS among Mast-ypN0 [hazard ratio (HR) = 0.729, 95% confidence interval (CI) 0.566-0.939, P = 0.015] and Mast-ypN+ patients (HR = 0.772, 95% CI 0.689-0.866, P < 0.001). No differences in OS were observed with the addition of RNI to breast RT for BCS-ypN0 or BCS-ypN+ patients. Propensity score-matched analyses demonstrated identical patterns of significance. On subset analysis, OS was improved with PMRT in each pathologic nodal subgroup (ypN0, ypN1, and ypN2-3) (all P < 0.05). CONCLUSIONS: In the largest reported analysis of RT for cN1 patients treated with NAC, PMRT was associated with improved OS for all pathologic nodal subgroups. No OS differences were observed with the addition of RNI to breast RT.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Neoadjuvant Therapy , Radiotherapy, Adjuvant , Adult , Aged , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Lymph Nodes/drug effects , Lymph Nodes/pathology , Lymph Nodes/radiation effects , Mastectomy , Mastectomy, Segmental , Middle Aged , Proportional Hazards Models
5.
Nat Commun ; 6: 6620, 2015 Mar 18.
Article in English | MEDLINE | ID: mdl-25782977

ABSTRACT

Current methods of chemical vapour deposition (CVD) of graphene on copper are complicated by multiple processing steps and by high temperatures required in both preparing the copper and inducing subsequent film growth. Here we demonstrate a plasma-enhanced CVD chemistry that enables the entire process to take place in a single step, at reduced temperatures (<420 °C), and in a matter of minutes. Growth on copper foils is found to nucleate from arrays of well-aligned domains, and the ensuing films possess sub-nanometre smoothness, excellent crystalline quality, low strain, few defects and room-temperature electrical mobility up to (6.0±1.0) × 10(4) cm(2) V(-1) s(-1), better than that of large, single-crystalline graphene derived from thermal CVD growth. These results indicate that elevated temperatures and crystalline substrates are not necessary for synthesizing high-quality graphene.

6.
Cell Death Dis ; 5: e1158, 2014 Apr 10.
Article in English | MEDLINE | ID: mdl-24722283

ABSTRACT

Human diseases of impaired ribosome biogenesis resulting from disruption of rRNA biosynthesis or loss of ribosomal components are collectively described as 'ribosomopathies'. Treacher Collins syndrome (TCS), a representative human ribosomopathy with craniofacial abnormalities, is attributed to mutations in the tcof1 gene that has a homologous gene called nopp140. Previous studies demonstrated that the dao-5 (dauer and aged animal overexpression gene 5) of Caenorhabditis elegans is a member of nopp140 gene family and plays a role in nucleogenesis in the early embryo. Here, we established a C. elegans model for studying Nopp140-associated ribosomopathy. A null dao-5 mutant ok542 with a semi-infertile phenotype showed a delay in gonadogenesis, as well as a higher incidence of germline apoptosis. These phenotypes in dao-5(ok542) are likely resulted from inefficient rDNA transcription that was observed by run-on analyses and chromatin immunoprecipitation (ChIP) assays measuring the RNA Pol I occupancy on the rDNA promoter. ChIP assays further showed that the modifications of acetylated histone 4 (H4Ac) and dimethylation at the lysine 9 of histone 3 (H3K9me2) around the rDNA promoter were altered in dao-5 mutants compared with the N2 wild type. In addition, activated CEP-1 (a C. elegans p53 homolog) activity was also linked to the loss of DAO-5 in terms of the transcriptional upregulation of two CEP-1 downstream effectors, EGL-1 and CED-13. We propose that the dao-5 mutant of C. elegans can be a valuable model for studying human Nopp140-associated ribosomopathy at the cellular and molecular levels.


Subject(s)
Apoptosis , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans/genetics , DNA, Ribosomal/genetics , DNA-Binding Proteins/genetics , Germ Cells/cytology , Mutation/genetics , Transcription, Genetic , Amino Acid Sequence , Animals , Caenorhabditis elegans/cytology , Caenorhabditis elegans Proteins/chemistry , Caenorhabditis elegans Proteins/metabolism , Cell Nucleolus/metabolism , Chromatin/metabolism , Chromosomal Proteins, Non-Histone/metabolism , Conserved Sequence , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Genes, Helminth , Germ Cells/metabolism , Gonads/abnormalities , Gonads/metabolism , Histones/metabolism , Humans , Models, Biological , Molecular Sequence Data , Promoter Regions, Genetic/genetics , Protein Structure, Tertiary , RNA Polymerase I/metabolism , Transcriptional Activation , Tumor Suppressor Protein p53/metabolism
7.
Oncogene ; 33(3): 308-15, 2014 Jan 16.
Article in English | MEDLINE | ID: mdl-23318451

ABSTRACT

The TRIM family of genes is largely studied because of their roles in development, differentiation and host cell antiviral defenses; however, roles in cancer biology are emerging. Loss of heterozygosity of the TRIM3 locus in ∼20% of human glioblastomas raised the possibility that this NHL-domain containing member of the TRIM gene family might be a mammalian tumor suppressor. Consistent with this, reducing TRIM3 expression increased the incidence of and accelerated the development of platelet-derived growth factor -induced glioma in mice. Furthermore, TRIM3 can bind to the cdk inhibitor p21(WAF1/CIP1). Thus, we conclude that TRIM3 is a tumor suppressor mapping to chromosome 11p15.5 and that it might block tumor growth by sequestering p21 and preventing it from facilitating the accumulation of cyclin D1-cdk4.


Subject(s)
Carrier Proteins/metabolism , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Glioblastoma/metabolism , Tumor Suppressor Proteins/metabolism , Animals , Carrier Proteins/genetics , Cell Line , Cell Line, Transformed , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p21/genetics , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Glioblastoma/pathology , Humans , Immunoblotting , Loss of Heterozygosity , Mice , Mice, Knockout , Mutation , Protein Binding , RNA Interference , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Suppressor Proteins/genetics
8.
Exp Clin Endocrinol Diabetes ; 121(7): 402-6, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23616188

ABSTRACT

AIM: Thyroid hormones regulate the rate of metabolism and affect the differentiation and growth of many tissues in the body. We investigated the association between hyperthyroidism and cancer risk in Taiwan. PATIENTS AND METHODS: A random sample of 1 000 000 individuals from Taiwan's National Health Insurance database was enrolled. We found 17 033 patients to have newly diagnosed hyperthyroidism between 2000 and 2005. These patients were recruited along with a match cohort of 34 066 patients without hyperthyroidism. Starting from index date, we followed up all patients for 4 years to identify those who developed cancer. RESULTS: During the 4-year follow-up study, cancer was diagnosed in 1.23% of patients with hyperthyroidism and 1.02% of the member of the comparison cohort. Regression analysis showed that patients with hyperthyroidism were at greater risk of cancer incidence, especially thyroid cancer, compared the comparison cohort (HR: 1.213; 95% CI: 1.022-1.440; p<0.05 and HR: 7.355; 95% CI: 3.885-13.92; p<0.05, respectively). After adjusting for age, gender, diabetes mellitus, hypertension, hyperlipidemia, gout, geographic region, and income, patients with hyperthyroidism remained at increased risk of cancer incidence and thyroid cancer (Adjusted HR: 1.206; 95% CI: 1.015-1.433 and 6.803; 95% CI: 3.584-12.91, respectively) (both p<0.05). The longer the duration of hyperthyroidism, the greater the risk of thyroid cancer. CONCLUSIONS: This 4-year follow up study suggests that patients with hyperthyroidism are at increased risk of cancer, especially thyroid cancer.


Subject(s)
Hyperthyroidism/complications , Hyperthyroidism/epidemiology , Thyroid Neoplasms/epidemiology , Adult , Aged , Female , Follow-Up Studies , Humans , Hyperthyroidism/pathology , Incidence , Male , Middle Aged , Retrospective Studies , Risk Factors , Taiwan/epidemiology , Thyroid Neoplasms/pathology , Time Factors
9.
Hum Reprod ; 28(4): 1023-30, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23300200

ABSTRACT

STUDY QUESTION: Why are female mice that lack a functional p27 protein infertile? SUMMARY ANSWER: The absence of a functional p27 leads to a dramatic increase in the number of multi-oocyte follicles (MOFs) in juvenile female mice; p27 would promote the individualization of follicles favoring the development of fertile eggs. WHAT IS KNOWN ALREADY: p27-/- female mice are infertile. p27 suppresses excessive follicular endowment and activation and promotes follicular atresia in mice. MATERIALS AND METHODS: Ovaries from wild type (WT) and p27Kip1 mutant mice aged 2, 4 and 12 weeks were subjected to immunohistochemistry/immunofluorescence. The slides with whole organs serially sectioned were scanned and examined by image analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Compared with WT, p27Kip1 mutant pre-pubertal mice had a greater number of oocytes, a greater number of growing follicles and a greater number of MOFs. These differences were statistically significant (P < 0.05), particularly in the case of MOFs (P > 0.001). The unusually large number of MOFs in juvenile p27-deficient mice is a novel observation. In WT mice p27 protein remains present in the oocyte nucleus but gradually decreases in the ooplasm during follicular growth, while granulosa cells show dynamic, follicle stage-related changes. LIMITATIONS, REASONS FOR CAUTION: These results have been obtained in mice and they cannot be directly extrapolated to humans. WIDER IMPLICATIONS OF THE FINDINGS: The dramatic increase in the numbers of MOFs in juvenile p27 mutants has not been previously reported. The number of MOFs declines sharply as the mice become sexually mature, pointing to their negative selection. These findings open a new approach to the study of sterility. STUDY FUNDING/COMPETING INTERESTS: This study has been funded by the Basque Government, Dept. of Health grant 2007111063 and Dept. of Industry (Saiotek) grant S-PC11UN008. Jairo Perez-Sanz was the recipient of a grant from Fundación Jesús de Gangoiti Barrera. The authors have no conflicts of interest to declare.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p27/genetics , Granulosa Cells/physiology , Mutation , Ovarian Follicle/pathology , Animals , Cyclin-Dependent Kinase Inhibitor p27/analysis , Female , Granulosa Cells/metabolism , Granulosa Cells/pathology , Immunohistochemistry , Infertility/genetics , Mice , Ovarian Follicle/growth & development , Ovarian Follicle/metabolism , Sexual Maturation
10.
Phys Rev Lett ; 106(8): 087004, 2011 Feb 25.
Article in English | MEDLINE | ID: mdl-21405593

ABSTRACT

Scanning tunneling spectroscopic studies of Ba(Fe(1-x)Co(x))(2)As(2) (x=0.06, 0.12) single crystals reveal direct evidence for predominantly two-gap superconductivity. These gaps decrease with increasing temperature and vanish above the superconducting transition T(c). The two-gap nature and the slightly doping- and energy-dependent quasiparticle scattering interferences near the wave vectors (±π, 0) and (0, ±π) are consistent with sign-changing s-wave superconductivity. The excess zero-bias conductance and the large gap-to-T(c) ratios suggest dominant unitary impurity scattering.

11.
Nano Lett ; 9(7): 2542-6, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19534500

ABSTRACT

Graphene has emerged as an electronic material that is promising for device applications and for studying two-dimensional electron gases with relativistic dispersion near two Dirac points. Nonetheless, deviations from Dirac-like spectroscopy have been widely reported with varying interpretations. Here we show evidence for strain-induced spatial modulations in the local conductance of single-layer graphene on SiO(2) substrates from scanning tunneling microscopic (STM) studies. We find that strained graphene exhibits parabolic, U-shaped conductance vs bias voltage spectra rather than the V-shaped spectra expected for Dirac fermions, whereas V-shaped spectra are recovered in regions of relaxed graphene. Strain maps derived from the STM studies further reveal direct correlation with the local tunneling conductance. These results are attributed to a strain-induced frequency increase in the out-of-plane phonon mode that mediates the low-energy inelastic charge tunneling into graphene.


Subject(s)
Electronics , Electrons , Graphite/chemistry , Silicon Dioxide/chemistry , Electric Conductivity , Gases , Materials Testing , Microscopy, Electron, Scanning , Surface Properties
12.
Phys Rev Lett ; 88(22): 227002, 2002 Jun 03.
Article in English | MEDLINE | ID: mdl-12059447

ABSTRACT

Quasiparticle tunneling spectra of the electron-doped ( n-type) infinite-layer cuprate Sr0.9La0.1CuO2 reveal characteristics that counter a number of common phenomena in the hole-doped ( p-type) cuprates. The optimally doped Sr0.9La0.1CuO2 with T(c) = 43 K exhibits a momentum-independent superconducting gap Delta = 13.0+/-1.0 meV that substantially exceeds the BCS value, and the spectral characteristics indicate insignificant quasiparticle damping by spin fluctuations and the absence of pseudogap. The response to quantum impurities in the Cu sites also differs fundamentally from that of the p-type cuprates with d(x(2)-y(2))-wave pairing symmetry.

13.
Phys Rev Lett ; 87(8): 087003, 2001 Aug 20.
Article in English | MEDLINE | ID: mdl-11497973

ABSTRACT

Scanning tunneling spectroscopy studies reveal long-range spatial homogeneity and predominantly d(x(2)-y(2))-pairing spectral characteristics in under- and optimally doped YBa2Cu 3O (7-delta) superconductors, whereas STS on YBa2(Cu 0.9934Zn 0.0026Mg (0.004))3O (6.9) exhibits microscopic spatial modulations and strong scattering near the Zn or Mg impurity sites, together with global suppression of the pairing potential. In contrast, in overdoped (Y 0.7Ca (0.3))Ba 2Cu 3O (7-delta), (d(x(2)-y(2))+s)-pairing symmetry is found, suggesting significant changes in the superconducting ground state at a critical doping value.

14.
Cancer Res ; 61(15): 5911-8, 2001 Aug 01.
Article in English | MEDLINE | ID: mdl-11479233

ABSTRACT

The proangiogenic activity of hepatocyte growth factor (HGF)/scatter factor has been closely associated with its ability to stimulate endothelial cell chemotaxis, migration, proliferation, and capillary formation. However, the potential of HGF as a paracrine factor in regulating the expression of angiogenesis factors by tumor cells is not widely appreciated. We observed that increased HGF was correlated with higher levels of angiogenesis factors interleukin (IL)-8 and vascular endothelial growth factor (VEGF) in serum of patients with head and neck squamous cell carcinoma (HNSCC) as compared with that in normal volunteers and hypothesized that HGF may regulate angiogenesis factor production by tumor cells through the activation of its receptor c-Met, which is expressed by HNSCC cells. To test this hypothesis, we examined the effect of HGF treatment on IL-8 and VEGF expression by a panel of primary keratinocytes and HNSCC lines. HGF induced a significant dose-dependent increase in IL-8 and/or VEGF cytokine production in eight HNSCC lines tested, which is not observed in normal keratinocytes. In addition, HGF increased mRNA expression of IL-8 in 3 of 6 and VEGF in 5 of 6 HNSCC lines. The increase in induction of these factors by HGF corresponded to an increase in phosphorylation of c-Met in HNSCC. HGF-induced phosphorylation of mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) pathway substrate p42/p44(erk) and phosphatidylinositol 3'-kinase (PI3K) pathway substrate Akt provided evidence for downstream activation of MEK and PI3K pathways in HNSCC. Inhibitors of MEK (U0126) and PI3K (LY294002) blocked p42/p44(erk) and Akt, respectively, and partially blocked HGF-induced production of IL-8 and VEGF, whereas the combination of U0126 and LY294002 completely inhibited expression of IL-8 and VEGF by UMSCC-11A. Our results demonstrate that HGF can promote expression of angiogenesis factors in tumor cells through both MEK- and PI3K-dependent pathways. Understanding HGF/Met paracrine regulatory mechanisms between tumor and host cells may provide critical information for targeting of therapies against angiogenesis.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Endothelial Growth Factors/biosynthesis , Head and Neck Neoplasms/metabolism , Hepatocyte Growth Factor/pharmacology , Interleukin-8/biosynthesis , Lymphokines/biosynthesis , MAP Kinase Kinase Kinase 1 , MAP Kinase Signaling System/physiology , Phosphatidylinositol 3-Kinases/metabolism , Protein Serine-Threonine Kinases/metabolism , Carcinoma, Squamous Cell/blood , Endothelial Growth Factors/blood , Endothelial Growth Factors/genetics , Enzyme Activation , Head and Neck Neoplasms/blood , Hepatocyte Growth Factor/blood , Hepatocyte Growth Factor/physiology , Humans , Interleukin-8/blood , Interleukin-8/genetics , Keratinocytes/drug effects , Keratinocytes/metabolism , Lymphokines/blood , Lymphokines/genetics , MAP Kinase Signaling System/drug effects , Phosphorylation/drug effects , Proto-Oncogene Proteins c-met/metabolism , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
15.
Clin Cancer Res ; 7(6): 1812-20, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11410524

ABSTRACT

Interleukin 1alpha (IL-1alpha) is an important regulatory cytokine, the release of which after an injury can induce activation of transcription factors nuclear factor (NF)kappaB and activator protein (AP-1), which promote expression of genes involved in cell survival, proliferation, and angiogenesis. IL-1alpha is expressed autonomously by head and neck squamous cell carcinomas (HNSCCs) and a variety of other cancers, raising the possibility that IL-1alpha may serve as an autocrine factor that stimulates the activation of prosurvival transcription factors and target genes in cancer. In this study, we examined the role of IL-1alpha in the activation of NFkappaB and AP-1, the expression of proangiogenic cytokine IL-8, and in the survival and proliferation of HNSCC cell lines. HNSCCs were found to secrete and respond to functional IL-1alpha, in that culture supernatant from a high IL-1alpha-secreting line, UM-SCC-11B, could induce secretion of cytokine IL-8 by a low IL-1alpha-secreting line, UM-SCC-9; and the induction of IL-8 secretion could be blocked by the anti-IL-1alpha-neutralizing antibody or the IL-1 receptor antagonist (IL-1RA). Furthermore, IL-1alpha could induce the expression of IL-8 through an autocrine mechanism, in that transfection of UM-SCC-9 cells with a plasmid encoding IL-1alpha resulted in the increased coexpression of IL-1alpha and IL-8; whereas transfection with a plasmid encoding IL-1RA lacking the secretory leader sequence led to the decreased coexpression of IL-1alpha and IL-8. IL-1alpha was found to induce coexpression of IL-8 through the activation of NFkappaB and AP-1, in that mutation of the NFkappaB site within the IL-8 promoter abolished autocrine- and recombinant IL-1alpha-induced IL-8 reporter gene activity, whereas mutation in AP-1 partially decreased IL-8 reporter gene activity in UM-SCC-9 cells. Intracellular expression of IL-1RA decreased NFkappaB reporter gene activity, indicating that endogenously expressed IL-1alpha contributes to constitutive NFkappaB activation in this HNSCC line. Expression of IL-1alpha affected survival of UM-SCC-9, inasmuch as transfection of cells with plasmid encoding IL-1alpha or IL-1RA led to the increased or decreased survival of cells cotransfected with a beta-galactosidase reporter gene, respectively. IL-1alpha was also found to promote the increased growth of UM-SCC-9 cells in vitro. We demonstrate that exogenous and endogenous IL-1alpha contributes to the transcriptional activation of NFkappaB and AP-1, to the expression of IL-8, and to cell survival and the growth of HNSCC in vitro.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Head and Neck Neoplasms/metabolism , Interleukin-1/metabolism , Interleukin-8/metabolism , NF-kappa B/metabolism , Transcription Factor AP-1/metabolism , Cell Division/drug effects , Cell Survival , Coloring Agents/pharmacology , Enzyme-Linked Immunosorbent Assay , Genes, Reporter , Genetic Vectors , Humans , Interleukin-8/biosynthesis , Mutation , Plasmids/metabolism , Recombinant Proteins/metabolism , Tetrazolium Salts/pharmacology , Thiazoles/pharmacology , Time Factors , Transcriptional Activation , Transfection , Tumor Cells, Cultured
16.
Clin Cancer Res ; 7(5): 1419-28, 2001 May.
Article in English | MEDLINE | ID: mdl-11350913

ABSTRACT

We have shown that activation of nuclear factor-kappa B (NF-kappa B) promotes cell survival and expression of cytokines such as growth-regulated oncogene-alpha, which can modulate angiogenesis, growth, and metastasis of squamous cell carcinoma (SCC). Activation of NF-kappa B and cytoprotective genes in cancer may result from signal-induced phosphorylation and proteasome-dependent degradation of inhibitor-kappa B. In this study, we examined the effects of the novel proteasome inhibitor PS-341 on activation of NF-kappa B and cell survival, growth, and angiogenesis in murine and human SCC cell lines. PS-341 inhibited activation of NF-kappa B DNA binding and functional reporter activity at concentrations between 10(-8) and 10(-7) M. Cytotoxicity was observed at 10(-7) M in four murine and two human SCC lines, and followed early cleavage of poly(ADP-ribose) polymerase, a marker of caspase-mediated apoptosis. In vivo, PS-341 inhibited growth of murine and human SCC in mice at doses of 1--2 mg/kg given three times weekly, and dose-limiting toxicity was encountered at 2 mg/kg. Tumor growth inhibition was associated with a marked decrease in vessel density. PS-341 inhibited expression of the proangiogenic cytokines growth-regulated oncogene-alpha and vascular endothelial growth factor by SCC in the range at which PS-341 inhibits NF-kappa B. We conclude that PS-341 inhibits activation of NF-kappa B pathway components related to cell survival, tumor growth, and angiogenesis in SCC.


Subject(s)
Antineoplastic Agents/pharmacology , Boronic Acids/pharmacology , Multienzyme Complexes/antagonists & inhibitors , NF-kappa B/antagonists & inhibitors , Pyrazines/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Blood Vessels/drug effects , Boronic Acids/therapeutic use , Bortezomib , Carcinoma, Squamous Cell , Cell Division/drug effects , Cell Survival/drug effects , Cysteine Endopeptidases , Cytokines/biosynthesis , Disease Models, Animal , Gene Expression/drug effects , Humans , Mice , Mice, Inbred BALB C , Mice, SCID , NF-kappa B/metabolism , Neoplasm Transplantation , Neoplasms, Experimental/drug therapy , Neovascularization, Pathologic/metabolism , Proteasome Endopeptidase Complex , Pyrazines/therapeutic use , Treatment Outcome , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
17.
Clin Cancer Res ; 7(2): 435-42, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11234901

ABSTRACT

Interleukin 8 (IL-8) and vascular endothelial growth factor (VEGF) promote tumor angiogenesis, growth, and metastasis and are coexpressed by human head and neck squamous cell carcinomas (HNSCCs) and a variety of other cancers. The promoters of the IL-8 and VEGF genes contain different recognition sites for transcription factors nuclear factor (NF)-kappaB and activator protein-1 (AP-1), which we showed previously are coactivated in HNSCCs. NF-kappaB and AP-1 may be modulated by the inhibitor kappaB kinase (IKK) and mitogen-activated protein kinase (MAPK) signal pathways, but the contribution of these pathways to expression of IL-8 and VEGF and as potential targets for antiangiogenesis therapy in HNSCC is not known. In this study, we examined the effects of modulation of the MAPK and IKK pathways on expression of IL-8 and VEGF by UM-SCC-9 and UM-SCC-11B cell lines. Interruption of IKK-mediated activation of NF-kappaB by expression of an inhibitor kappaB alpha mutant (IkappaB alphaM) in UM-SCC-9 cells resulted in partial inhibition of expression of IL-8 but not VEGF. Analysis of possible alternative pathways for induction of these genes revealed activation of the MAPK extracellular signal-regulated kinase (ERK1/2) in cell lines UM-SCC-9 and UM-SCC-11B. Basal and tumor necrosis factor-alpha-inducible phosphorylation of ERK1/2 and secretion of IL-8 and VEGF could be specifically inhibited by a MEK inhibitor, U0126. Expression of IL-8 and VEGF in the cell lines was associated with coactivation of both NF-kappaB and AP-1, and U0126 inhibited both NF-kappaB and AP-1 reporter activity in UM-SCC-9 and UM-SCC-11B cells. The ERK pathway appears to contribute to expression of IL-8 and VEGF and transactivation of NF-kappaB as well as AP-1 in HNSCC. Combined inhibition of both MAPK and IKK pathways may be needed for suppression of the signal transduction mechanism(s) regulating VEGF and IL-8 secretion and angiogenesis by human HNSCC.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Endothelial Growth Factors/metabolism , Head and Neck Neoplasms/metabolism , Interleukin-8/metabolism , Lymphokines/metabolism , MAP Kinase Kinase Kinase 1 , Mitogen-Activated Protein Kinase Kinases/metabolism , NF-kappa B/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , Butadienes/pharmacology , Carcinoma, Squamous Cell/genetics , Enzyme Inhibitors/pharmacology , Head and Neck Neoplasms/genetics , Humans , I-kappa B Kinase , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/metabolism , Nitriles/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Transcription Factor AP-1/metabolism , Transfection , Tumor Cells, Cultured , Tumor Necrosis Factor-alpha/pharmacology , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
18.
Mol Cell Biol ; 19(12): 8536-46, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10567578

ABSTRACT

Nopp140 is thought to shuttle between nucleolus and cytoplasm. However, the predominant nucleolar localization of Nopp140 homologues from different species suggests that Nopp140 is also involved in events occurring within the nucleolus. In this study, we demonstrated that the largest subunit of RNA polymerase I, RPA194, was coimmunoprecipitated with the human Nopp140 (hNopp140). Such an interaction is mediated through amino acids 204 to 382 of hNopp140. By double immunofluorescence, hNopp140 was colocalized with RNA polymerase I at the rDNA (rRNA genes) transcription active foci in the nucleolus. These results suggest that Nopp140 can interact with RNA polymerase I in vivo. Transfected cells expressing the amino-terminal half of hNopp140, hNopp140N382 (amino acids 1 to 382), displayed altered nucleoli with crescent-shaped structures. This phenotype is reminiscent of the segregated nucleoli induced by actinomycin D treatment, which is known to inhibit rRNA synthesis. Consistently, the hNopp140N382 protein mislocalized the endogenous RNA polymerase I and shut off cellular rRNA gene transcription as revealed by an in situ run-on assay. These dominant negative effects of the mutant hNopp140N382 suggest that Nopp140 plays an essential role in rDNA transcription. Interestingly, ectopic expression of hNopp140 to a very high level caused the formation of a transcriptionally inactive spherical structure occupying the entire nucleolar area which trapped the RNA polymerase I, fibrillarin, and hNopp140 but excluded the nucleolin. The mislocalizations of these nucleolar proteins after hNopp140 overexpression imply that Nopp140 may also play roles in maintenance of nucleolar integrity.


Subject(s)
Cell Nucleolus/metabolism , Nuclear Proteins/metabolism , Nucleolus Organizer Region , Phosphoproteins/metabolism , RNA, Ribosomal , Transcription, Genetic , Animals , Binding Sites , COS Cells , Casein Kinase II , Gene Expression , HeLa Cells , Humans , Nuclear Proteins/genetics , Phosphoproteins/genetics , Precipitin Tests , Protein Serine-Threonine Kinases/metabolism , RNA Polymerase I/metabolism , Sequence Deletion , Tumor Cells, Cultured
19.
Clin Cancer Res ; 5(6): 1369-79, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10389921

ABSTRACT

Altered immune, inflammatory, and angiogenesis responses are observed in patients with head and neck squamous cell carcinoma (HNSCC), and many of these responses have been linked with aggressive malignant behavior and a decrease in prognosis. In this study, we examined the hypothesis that HNSCC cells produce cytokines that regulate immune, inflammatory, and angiogenesis responses. We identified important regulatory cytokines in supernatants of well-defined and freshly cultured HNSCC cell lines by ELISA and determined whether these cytokines are detected in tumor cell lines and tissue specimens by immunohistochemistry. The serum concentration of the cytokines and cytokine-dependent acute phase inflammatory responses (i.e., fibrinogen, C-reactive protein, and erythrocyte sedimentation rate) from patients with HNSCC was determined, and the potential relationship of serum cytokine levels to tumor volume was analyzed. Cytokines interleukin (IL)-1alpha, IL-6, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor were detected in similar concentration ranges in the supernatants of a panel of established University of Michigan squamous cell carcinoma (UM-SCC) cell lines and supernatants of freshly isolated primary HNSCC cultures. Evidence for the expression of IL-1alpha, IL-6, IL-8, granulocyte-macrophage colony-stimulating factor, and VEGF in HNSCC cells within tumor specimens in situ was obtained by immunohistochemistry. In a prospective comparison of the cytokine level and cytokine-inducible acute-phase proteins in serum, we report that cytokines IL-6, IL-8, and VEGF were detected at higher concentrations in the serum of patients with HNSCC compared with patients with laryngeal papilloma or age-matched control subjects (at P < 0.05). The serum concentrations of IL-8 and VEGF were found to be weakly correlated with large primary tumor volume (R2 = 0.2 and 0.4, respectively). Elevated IL-1- and IL-6-inducible acute-phase responses were also detected in cancer patients but not in patients with papilloma or control subjects (at P < 0.05). We therefore conclude that cytokines important in proinflammatory and proangiogenic responses are detectable in cell lines, tissue specimens, and serum from patients with HNSCC. These cytokines may increase the pathogenicity of HNSCC and prove useful as biomarkers or targets for therapy.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Cytokines/metabolism , Head and Neck Neoplasms/metabolism , Acute-Phase Reaction/immunology , Adult , Aged , Endothelial Growth Factors/metabolism , Enzyme-Linked Immunosorbent Assay , Female , Fibroblast Growth Factor 2/metabolism , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Humans , Immunohistochemistry , Inflammation/metabolism , Interleukin-1/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Lymphokines/metabolism , Male , Middle Aged , Prospective Studies , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
20.
J Urol ; 159(3): 754-7, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9474141

ABSTRACT

PURPOSE: With the patient standing and supine we determine the differences in dynamic changes of the bladder neck and directions of dynamic bladder neck displacement. MATERIALS AND METHODS: To evaluate the dynamic movement of the bladder neck we recruited into the study 78 consecutive women 27 to 69 years old with various urogynecological complaints. The anatomical changes of the bladder neck from rest to maximal straining and from rest to holding were evaluated and compared with the patients supine and standing. RESULTS: Except for bladder neck rotational angle with the patient standing, all parameters were significantly different from corresponding measurements with the patient supine. Mean rotational angle of rest to maximal straining plus or minus standard deviation was 39.4 +/- 18.9 degrees when standing versus 39.8 +/- 23.4 degrees when supine (p > 0.05). The distances between the bladder neck and symphysis pubis at rest, and during maximal straining and holding the bladder neck in the supine position were significantly longer than those in the standing position. The direction of bladder neck displacement from rest to maximal straining was more caudad and ventral when standing. The bladder neck moved cephalad and ventral when the patient was standing, and cephalad and dorsal with the patient supine and holding the bladder neck. CONCLUSIONS: The anatomical locations and dynamic displacements of the bladder neck at rest, and during maximal straining and holding were significantly different in the supine and standing positions. While evaluating the dynamic motion of the bladder neck to determine bladder neck mobility, patient position must be considered and specified in accordance with diagnostic standards.


Subject(s)
Posture , Urinary Bladder/anatomy & histology , Adult , Aged , Female , Humans , Male , Middle Aged , Posture/physiology , Prospective Studies , Urinary Bladder/physiology , Urination , Urodynamics
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