| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Cell, Tumor, and Stem Cell Biology |
1 Vascular Biology Program, Institute for Cell Engineering; Departments of Pediatrics, Medicine, Oncology, and Radiation Oncology; and McKusick-Nathans Institute for Genetic Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; and 2 Microvascular and Molecular Neuro-Oncology Laboratory, Departments of Pathology and Neurosurgery, New York University Cancer Institute of New York University School of Medicine, New York, New York
Requests for reprints: Gregg L. Semenza, Johns Hopkins University School of Medicine, Broadway Research Building, 733 North Broadway, Suite 671, Baltimore, MD 21205. Fax: 443-287-5618; E-mail: gsemenza{at}jhmi.edu.
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResults and DiscussionReferences |
|---|
mutant, or a short hairpin RNA directed against HIF-1. In human RCC biopsies, expression of E-cadherin and HIF-1 was mutually exclusive. The expression of mRNAs encoding TCF3, ZFHX1A, and ZFHX1B, which repress E-cadherin gene transcription, was increased in VHL-null RCC4 cells in a HIF-1–dependent manner. Thus, HIF-1 contributes to the epithelial-mesenchymal transition in VHL-null RCC by indirect repression of E-cadherin. (Cancer Res 2006; 66(5): 2725-31) |
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResults and DiscussionReferences |
|---|
E-cadherin loss of function occurs via a variety of molecular mechanisms in different human cancers (4), including mutations in the CDH1 gene that encodes E-cadherin (5, 6), increased E-cadherin degradation (7), and decreased CDH1 mRNA expression associated with CDH1 hypermethylation indicating transcriptional silencing (8, 9). The repressors SLUG, SNAIL, TCF3 (also known as E12/E47), ZFHX1A (also known as 
EF1 or ZEB1), and ZFHX1B (also known as SIP1 or ZEB2) have been shown to bind to the proximal promoter of CDH1, repress its transcription, and induce the epithelial-mesenchymal transition (10–16). Increased expression of one or more of these repressors has been correlated with decreased CDH1 mRNA expression in human cancers, but the molecular basis for these observations has not been determined.
The conventional clear cell type of renal cell carcinoma (RCC) is associated with loss of function of the von Hippel-Lindau tumor suppressor (VHL) protein as a result of VHL gene mutation or hypermethylation (17). A principal function of VHL is to negatively regulate hypoxia-inducible factor-1 (HIF-1), a transcriptional activator of genes that play key roles in angiogenesis, cell proliferation/survival, energy metabolism, invasion, and resistance to radiation and chemotherapy (18–23). The constitutively expressed HIF-1ß subunit forms functional heterodimers with either HIF-1 or HIF-2 (24, 25). VHL binds to HIF-1 and HIF-2 and targets them for ubiquitination and proteasomal degradation (26). VHL binding is dependent upon the O2-dependent hydroxylation of specific proline residues in HIF-1 and HIF-2 (27, 28).
VHL loss of function leading to HIF-1 gain of function is the earliest detectable molecular event in the pathogenesis of RCC (29). However, the molecular basis for the epithelial-mesenchymal transition in RCC has not been determined, and the identification of proteins regulated by VHL in addition to HIF-1 has raised the possibility that key steps in RCC pathogenesis are independent of HIF-1 (17). In this study, we investigated whether dysregulated HIF-1 activity contributes to down-regulation of E-cadherin expression, loss of cell-cell adhesion, and the epithelial-mesenchymal transition in RCC.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResults and DiscussionReferences |
|---|
DN retroviral shuttle vectors. Enhanced green fluorescent protein (EGFP) sequences were amplified using pEGFP-N (Clontech, Palo Alto, CA) as template and inserted into retroviral vector pQCXIH (Clontech). The open reading frame from pCEP-4-HIF-1DN (30) was amplified by PCR and inserted into retroviral vector pQCXIN (Clontech).
Retrovirus production and generation of stable cell lines. 293-T cells were seeded at 7 x 106 per 10-cm dish. Retroviral vector DNA (12 µg) encoding EGFP or HIF-1DN was cotransfected with plasmids encoding gag/pol (6 µg) and VSVG (1.5 µg) using LipofectAMINE 2000. Viral supernatant was collected 48 hours after transfection and added to RCC4 cells in the presence of polybrene (8 µg/mL; Sigma, St. Louis, MO). The procedure was repeated at 60 and 72 hours after transfection. Hygromycin (400 µg/mL) or G418 (800 µg/mL) was added to the culture media, starting at 96 hours after transfection of pQCXIH-EGFP or pQCXIN-HIF-1DN, respectively. Pooled clones of resistant cells were cultured in DMEM (Mediatech, Herndon, VA) with 10% fetal bovine serum (FBS; Gemini, Calabasas, CA) and 1% penicillin/streptomycin starting 24 hours before all studies.
RNA isolation and quantitative real-time reverse-transcription PCR. Total RNA was isolated from cells using QIAshredder and RNeasy Mini Kits (Qiagen, Chatsworth, CA). cDNA was prepared using the iScript cDNA Synthesis kit (Bio-Rad, Richmond, CA). cDNA samples were diluted 1:15, and real-time PCR was performed using IQ SYBR Green Supermix and specific primers in the iCycler Real-time PCR detection system (Bio-Rad). Primers were designed using Beacon Designer 2.1 software (sequences available on request). Annealing temperature was optimized for each primer pair. The expression of each target mRNA relative to 18S rRNA (R) was calculated based on the threshold cycle (Ct) as R = 2–
(Ct), where Ct = Ct, target – Ct, 18s and (Ct) = Ct, RCC4 – Ct, RCC4-VHL or Ct, RCC4-GFP – Ct, RCC4-DN or Ct, GFP-EV – Ct, GFP-shr2265.
Immunoblot assays. Cells were lysed in radioimmunoprecipitation assay buffer supplemented with protease inhibitors; 60-µg aliquots of protein were resolved by 7% PAGE and transferred to a nitrocellulose membrane. A monoclonal antibody (mAb) directed against the extracellular domain (clone HECD1, Zymed Laboratories, South San Francisco, CA; 1:3,000 dilution) or intracellular domain (clone 36, BD Biosciences, San Jose, CA; 1:3,000 dilution) of E-cadherin was used. Immunoblot assays of HIF-1 (mAb H167) and HIF-2 (rabbit polyclonal antibody, NB-100-122, Novus Biologicals, Littleton, CO) were performed using 100-µg aliquots of lysate. Horseradish peroxidase (HRP)–conjugated secondary antibody against mouse (goat anti-mouse, Santa Cruz Biotechnology, Santa Cruz, CA) or rabbit (donkey anti-rabbit, Amersham, Arlington Heights, IL) immunoglobulin was used for detection. ß-Actin was detected using a goat polyclonal antibody against ß-actin and HRP-conjugated donkey anti-goat secondary antibody (Santa Cruz Biotechnology). Immunoblots were developed using enhanced chemiluminescence (Amersham Biosciences, Piscataway, NJ).
Transepithelial resistance assays. In a modified Boyden chamber (BD Biosciences), 1 x 104 cells resuspended in 2.5 mL of media were added to the upper chamber, and 3.5 mL of media were added to the lower chamber, in triplicate. Resistance was measured using an epithelial voltohmmeter (EVOM, World Precision Instruments, Sarasota, FL). A blank with no cells was maintained, and the average resistance from the blank was subtracted from the sample. Resistance (R) per unit area was calculated as (Rsample – Rblank) x 
d2/4, where d = diameter (in cm) of the chamber.
Immunocytochemistry. Cells (5 x 103 per well) were seeded into an eight-well chamber slide precoated with poly-D-lysine. Cells were fixed with 4% paraformaldehyde for 10 minutes and washed with 0.5% bovine serum albumin (BSA) in PBS. Blocking was carried out at room temperature for 30 minutes using normal goat serum. Upon permeabilization with 0.1% Triton X-100 in 0.5% BSA/PBS, cells were incubated with primary antibody against E-cadherin (clone 36, BD Biosciences) overnight. Cells were incubated with phycoerythrin-conjugated secondary antibody (BD Biosciences) at 1:500 dilution for 1 hour at room temperature. Before mounting the slide, 4',6-diamidino-2-phenylindole (Molecular Probes, Eugene, OR) was added to 300 nmol/L. Phycoerythrin-conjugated IgG2A (R&D Systems, Inc., Minneapolis, MN) was used as an isotype-matched control. The sections were photographed under fluorescent microscopy (Olympus BX51 mounted with Olympus DP70 camera).
Retroviral expression of short hairpin RNA in RCC4 cells. Short hairpin RNA (shRNA) specific for HIF-1 was identified using the manufacturer's design tool (OligoEngine, Seattle, WA). Oligonucleotides meeting the standards was annealed and cloned into BglII- and HindIII-digested pSUPER-Retro-neo-GFP (OligoEngine). In this vector, shRNA and GFP mRNA expression are driven by H1 and phosphoglycerate kinase promoter sequences, respectively. Retrovirus was generated by cotransfecting 293T cells with the shRNA vector and a second vector encoding gag/pol and VSVG using LipofectAMINE 2000 (Invitrogen, San Diego, CA). The supernatant was collected 48 hours after transfection, centrifuged, and directly used for infection of 1 x 105 RCC4 cells per well in a six-well plate, using 2 mL of viral supernatant and polybrene at a final concentration of 8 µg/mL. Three rounds of retroviral infection were performed at 24-hour intervals. A pool of cells was selected by treatment with G418 at a concentration of 800 µg/mL. Cells were maintained in DMEM containing 10% FBS, 1% penicillin/streptomycin, and 600 µg/mL G418.
Immunohistochemistry. Formalin-fixed, 6-µm-thick sections were stained for HIF-1 using Catalyzed Signal Amplification (DAKO, Carpinteria, CA) and mAb H167 (1 mg/mL, Novus Biologicals; 1:10,000 dilution) as previously described (31). Nuclei were counterstained with hematoxylin. As a negative control, nonimmune serum was used in lieu of the primary antibody. Immunohistochemistry for E-cadherin was performed using mouse anti-human E-cadherin clone 4A2C7 (Invitrogen). Epitope retrieval was performed in 10 mmol/L citrate buffer (pH 6) for 20 minutes in a 1,200-W microwave oven at 90% power. Antibody incubation and detection were carried out on a NEXes instrument (Ventana Medical Systems, Tucson, AZ). Endogenous peroxidase activity was blocked with hydrogen peroxide. E-cadherin antibody was diluted 1:100 in PBS, applied, and incubated overnight at room temperature. Primary antibody was detected using biotinylated goat anti-mouse antibody followed by streptavidin-HRP conjugate and visualized with 3,3-diaminobenzidene enhanced with copper sulfate. Slides were washed in distilled water, counterstained with hematoxylin, dehydrated, and mounted.
Statistical analysis. Student's t test and ANOVA were performed using Excel (Microsoft, Redmond, WA).
|
Results and Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResults and DiscussionReferences |
|---|
and HIF-2 protein under nonhypoxic conditions, as previously described (32), showing loss of physiologic regulation in the absence of VHL, which was corrected by restoration of VHL expression (Fig. 1A). In contrast, levels of the HIF-1ß subunit and ß-actin were unaffected by the presence or absence of VHL. E-cadherin protein was not detected in lysates of VHL-null RCC4 cells using antibodies directed against either the extracellular domain, which is the site of homophilic interactions, or the intracellular domain, which interacts with catenins that link E-cadherin to the cytoskeleton. Upon restoration of VHL expression, increased levels of E-cadherin protein were detected with both antibodies (Fig. 1A). Immunocytochemistry confirmed the low levels of E-cadherin protein in RCC4 cells and the markedly increased E-cadherin levels in RCC4-VHL cells (Fig. 2).
|
|
Expression of E-cadherin in RCC4 cells is negatively regulated by HIF-1. To determine whether the dysregulated expression of HIF-1 and HIF-2 in RCC4 cells contributed to the loss of E-cadherin expression, the RCC4-DN subclone was established by stable transfection of RCC4 cells with a retroviral expression vector encoding a dominant-negative form of HIF-1 that competes with endogenous HIF-1 and HIF-2 for binding to HIF-1ß, resulting in the formation of HIF-1DN:HIF-1ß heterodimers that cannot bind to DNA or activate transcription (30). In addition, the dominant-negative form of HIF-1 unexpectedly inhibited HIF-2 protein expression (Fig. 1C). RCC4-DN cells showed increased expression of E-cadherin protein relative to RCC4-GFP cells, which were stably transfected with a retroviral expression vector encoding GFP.
Loss of HIF-1 activity was associated with 4.2-fold decreased VEGF mRNA expression in RCC4-DN cells compared with RCC-GFP cells (Fig. 1D). RCC4-DN cells showed 9.8-fold increased expression of E-cadherin mRNA relative to RCC4-GFP cells (Fig. 1D). Increased E-cadherin protein expression in RCC4-DN cells relative to RCC-GFP cells was also shown by immunocytochemistry (Fig. 2). Thus, in RCC4 cells, the loss of E-cadherin expression that is associated with VHL loss of function is mediated by HIF-1.
Evidence of epithelial-mesenchymal transformation of VHL-null RCC4 cells. To investigate the functional consequences associated with the presence or absence of E-cadherin expression in RCC4 cells, we analyzed transepithelial resistance as a measure of cell-cell adhesion in RCC4 and RCC4-VHL cells over 6 days in culture. VHL loss of function was associated with a highly significant reduction in transepithelial resistance at all time points (Fig. 3A). Comparison of RCC4-GFP and RCC4-DN cells revealed that expression of the dominant-negative form of HIF-1, which was associated with a derepression of E-cadherin expression, also resulted in an increase in transepithelial resistance at all time points relative to RCC4-GFP cells (Fig. 3C). The rate of RCC4 and RCC4-GFP cell proliferation was increased compared with RCC4-VHL and RCC4-DN, respectively (Fig. 3B and D). Thus, the transepithelial resistance measurements, which were not corrected for cell number, understate the differences between subclones. From these results, we conclude that VHL loss of function in RCC4 cells is associated with a HIF-1–dependent loss of transepithelial resistance, which is consistent with a loss of adherens junctions due to reduced E-cadherin expression.
|
is specifically required for E-cadherin repression in RCC4 cells. HIF-1DN competes with both HIF-1 and HIF-2 for dimerization with HIF-1ß. HIF-1 heterodimers containing HIF-1 or HIF-2 have an overlapping but distinct set of transcriptional targets (32, 33). To determine whether HIF-1 was specifically required for the loss of E-cadherin expression in VHL-null RCC4 cells, we established by retroviral infection stable RCC4 subclones expressing GFP alone (RCC4-GFP-EV) or GFP and a shRNA (RCC4-GFP-shr2265), which modestly reduced the levels of HIF-1 protein (Fig. 4A) and mRNA (Fig. 4B) and the levels of VEGF mRNA. Despite the modest level of inhibition, E-cadherin protein and mRNA levels were increased significantly in RCC4-GFP-shr2265 compared with RCC4-GFP-EV cells. Immunocytochemistry revealed that compared with RCC4-GFP-EV cells, E-cadherin expression in RCC4-GFP-shr2265 cells was markedly increased (Fig. 4C). The increase in E-cadherin expression was associated with a significant increase in the transepithelial resistance of RCC4-GFP-shr2265 cells compared with RCC4-GFP-EV cells (Fig. 4D). Thus, interference with HIF-1 expression in RCC4 cells is sufficient for derepression of E-cadherin and increased cell-cell adhesion.
|
and E-cadherin in human RCC biopsies. To investigate whether the relationship between VHL, HIF-1, and E-cadherin that we have shown in RCC4 cells is clinically relevant, we analyzed E-cadherin expression by immunohistochemistry. In sections of normal kidney, E-cadherin was specifically detected within the distal convoluted tubules but not in proximal tubules (Fig. 5, top). Next, 13 RCC biopsies were analyzed. Eleven of these biopsies were classic clear cell renal carcinomas, in which HIF-1 was strongly expressed in the nuclei of all tumor cells, and E-cadherin expression was not detected (Fig. 5, middle). These data are difficult to interpret because it is not possible to determine whether the tumors arose from proximal or distal tubules. The most informative cases were two RCCs with mixed clear cell and granular morphology, both of which manifested the following pattern of HIF-1 and E-cadherin expression. In the areas of clear cell morphology, nuclear HIF-1 overexpression was detected, and E-cadherin expression was absent (Fig. 5, bottom). In contrast, the contiguous areas of granular morphology lacked detectable HIF-1 expression and manifested strong E-cadherin expression. Thus, within individual human RCC biopsies, expression of HIF-1 and E-cadherin was mutually exclusive.
|
EF1/ZEB1), and ZFHX1B (SIP1/ZEB2) mRNAs in RCC4 compared with RCC4-VHL cells (Fig. 6A, top) and in RCC4-GFP compared with RCC4-DN cells (Fig. 6A, bottom). Among these three repressors, ZFHX1B showed the greatest loss of expression in response to VHL or HIF-1DN and was the only repressor whose expression was decreased in response to shr2265 (data not shown), which may reflect the more modest reduction in HIF-1 transcriptional activity achieved in RCC4-GFP-shr2265 cells compared with RCC4-VHL or RCC4-DN cells.
|
The demonstration of a reciprocal relationship between HIF-1 and E-cadherin expression in human RCC biopsies suggests that the mechanism deduced from molecular analysis of RCC4 subclones may have clinical relevance. VHL loss of function leading to HIF-1 gain of function is the earliest detectable molecular event in the pathogenesis of RCC (29), but the key HIF-1–mediated changes in gene expression that induce RCC transformation were previously undetermined. Our data implicate HIF-1–mediated loss of E-cadherin expression as a critical event underlying the epithelial-to-mesenchymal transition in RCC. However, as described in the Introduction, multiple mechanisms resulting in E-cadherin loss of function have been reported in other cancers, and there is no reason to suppose that these may not also occur in some cases of RCC. In support of this hypothesis, the VHL-null RCC line 786-0 does not express E-cadherin after VHL rescue (data not shown). Further studies are required to determine the extent to which this mechanism is responsible for loss of E-cadherin expression in other human cancers.
|
Acknowledgments |
|---|
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
We thank Linzhao Cheng (Johns Hopkins University, Baltimore, MD) for providing retroviral packaging vectors and advice on viral production: Luis Chiriboga (New York University, New York, NY) for technical assistance, Garry Cutting (Johns Hopkins University) for use of his voltohmmeter, Karen Padgett (Novus Biologicals, Littleton, CO) for providing anti-HIF-2 antibodies, and Celeste Simon (University of Pennsylvania, Philadelphia, PA) for providing RCC4 and RCC4-VHL cells.
Received 10/13/05. Revised 10/14/05. Accepted 12/29/05.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResults and DiscussionReferences |
|---|
EF1 is a transcriptional repressor of E-cadherin and regulates epithelial plasticity in breast cancer cells. Oncogene 2005;24:2375–85.[CrossRef][Medline] targeted for VHL-mediated destruction by proline hydroxylation: implications for O2 sensing. Science 2001;292:464–8. to the von Hippel-Lindau ubiquitylation complex by O2-regulated prolyl hydroxylation. Science 2001;292:468–72. in common human cancers and their metastases. Cancer Res 1999;59:5830–5. (HIF-1) and HIF-2 in hypoxic gene regulation. Mol Cell Biol 2003;23:9361–74.This article has been cited by other articles:
|
|
 |
|
  T. Liu, C. P. Masamha, S. Chengedza, K. D. Berlin, S. Lightfoot, F. He, and D. M. Benbrook Development of flexible-heteroarotinoids for kidney cancer Mol. Cancer Ther., May 1, 2009; 8(5): 1227 - 1238. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. Wacker, M. Sachs, K. Knaup, M. Wiesener, J. Weiske, O. Huber, Z. Akcetin, and J. Behrens Key Role for Activin B in Cellular Transformation after Loss of the von Hippel-Lindau Tumor Suppressor Mol. Cell. Biol., April 1, 2009; 29(7): 1707 - 1718. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Scortegagna, R. J. Martin, R. D. Kladney, R. G. Neumann, and J. M. Arbeit Hypoxia-Inducible Factor-1{alpha} Suppresses Squamous Carcinogenic Progression and Epithelial-Mesenchymal Transition Cancer Res., March 15, 2009; 69(6): 2638 - 2646. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. K. Harten, D. Shukla, R. Barod, A. Hergovich, M. S. Balda, K. Matter, M. A. Esteban, and P. H. Maxwell Regulation of Renal Epithelial Tight Junctions by the von Hippel-Lindau Tumor Suppressor Gene Involves Occludin and Claudin 1 and Is Independent of E-Cadherin Mol. Biol. Cell, February 1, 2009; 20(3): 1089 - 1101. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Zheng, J. Kuhlicke, K. Jackel, H. K. Eltzschig, A. Singh, M. Sjoblom, B. Riederer, C. Weinhold, U. Seidler, S. P. Colgan, et al. Hypoxia inducible factor-1 (HIF-1)-mediated repression of cystic fibrosis transmembrane conductance regulator (CFTR) in the intestinal epithelium FASEB J, January 1, 2009; 23(1): 204 - 213. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. L. Semenza Does Loss of CD151 Expression Promote the Metastasis of Hypoxic Colon Cancer Cells? Clin. Cancer Res., December 15, 2008; 14(24): 7969 - 7970. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Feijoo-Cuaresma, F. Mendez, A. Maqueda, M. A. Esteban, S. Naranjo-Suarez, M. C. Castellanos, M. H. del Cerro, S. N. Vazquez, A. Garcia-Pardo, M. O. Landazuri, et al. Inadequate Activation of the GTPase RhoA Contributes to the Lack of Fibronectin Matrix Assembly in von Hippel-Lindau Protein-defective Renal Cancer Cells J. Biol. Chem., September 5, 2008; 283(36): 24982 - 24990. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. J. Frew and W. Krek pVHL: A Multipurpose Adaptor Protein Sci. Signal., June 17, 2008; 1(24): pe30 - pe30. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Beltran, I. Puig, C. Pena, J. M. Garcia, A. B. Alvarez, R. Pena, F. Bonilla, and A. G. de Herreros A natural antisense transcript regulates Zeb2/Sip1 gene expression during Snail1-induced epithelial-mesenchymal transition Genes & Dev., March 15, 2008; 22(6): 756 - 769. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. L. Semenza Hypoxia-inducible Factor 1 and Human Cancer ASCO Educational Book, January 1, 2008; 2008(1): 548 - 551. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Scheel, T. Onder, A. Karnoub, R. A. Weinberg, and J. E. Talmadge Adaptation versus Selection: The Origins of Metastatic Behavior Cancer Res., December 15, 2007; 67(24): 11476 - 11480. [Full Text] [PDF]
|
|
|
|
 |
|
 X. Xia, T. Rasmussen, X. Alvarez, T. Taguchi, M. Li, and V. F. La Russa Fluorescence In Situ Hybridization Using an Old World Monkey Y Chromosome specific Probe Combined With Immunofluorescence Staining on Rhesus Monkey Tissues J. Histochem. Cytochem., November 1, 2007; 55(11): 1115 - 1121. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-w. Kim, P. Gao, Y.-C. Liu, G. L. Semenza, and C. V. Dang Hypoxia-Inducible Factor 1 and Dysregulated c-Myc Cooperatively Induce Vascular Endothelial Growth Factor and Metabolic Switches Hexokinase 2 and Pyruvate Dehydrogenase Kinase 1 Mol. Cell. Biol., November 1, 2007; 27(21): 7381 - 7393. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Mejlvang, M. Kriajevska, C. Vandewalle, T. Chernova, A. E. Sayan, G. Berx, J. K. Mellon, and E. Tulchinsky Direct Repression of Cyclin D1 by SIP1 Attenuates Cell Cycle Progression in Cells Undergoing an Epithelial Mesenchymal Transition Mol. Biol. Cell, November 1, 2007; 18(11): 4615 - 4624. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Wang, C. Sloss, X. Zhang, S. W. Lee, and J. C. Cusack Membrane-Bound Heparin-Binding Epidermal Growth Factor Like Growth Factor Regulates E-Cadherin Expression in Pancreatic Carcinoma Cells Cancer Res., September 15, 2007; 67(18): 8486 - 8493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Li, L. Zhang, X. Zhang, Q. Yan, Y. A. Minamishima, A. F. Olumi, M. Mao, S. Bartz, and W. G. Kaelin Jr. Hypoxia-Inducible Factor Linked to Differential Kidney Cancer Risk Seen with Type 2A and Type 2B VHL Mutations Mol. Cell. Biol., August 1, 2007; 27(15): 5381 - 5392. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. D. Lester, M. Jo, V. Montel, S. Takimoto, and S. L. Gonias uPAR induces epithelial mesenchymal transition in hypoxic breast cancer cells J. Cell Biol., July 24, 2007; 178(3): 425 - 436. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. G. Kaelin Jr. The von Hippel-Lindau Tumor Suppressor Protein and Clear Cell Renal Carcinoma Clin. Cancer Res., January 15, 2007; 13(2): 680s - 684s. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. Evans, R. C. Russell, O. Roche, T. N. Burry, J. E. Fish, V. W. K. Chow, W. Y. Kim, A. Saravanan, M. A. Maynard, M. L. Gervais, et al. VHL Promotes E2 Box-Dependent E-Cadherin Transcription by HIF-Mediated Regulation of SIP1 and Snail Mol. Cell. Biol., January 1, 2007; 27(1): 157 - 169. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. L. Semenza Baffled by Bafilomycin: An Anticancer Agent That Induces Hypoxia-Inducible Factor-1{alpha} Expression Mol. Pharmacol., December 1, 2006; 70(6): 1841 - 1843. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Q. Zhang, S.-Y. Wang, A. C. Nottke, J. V. Rocheleau, D. W. Piston, and R. H. Goodman Redox sensor CtBP mediates hypoxia-induced tumor cell migration PNAS, June 13, 2006; 103(24): 9029 - 9033. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Garcia HIFing the Brakes: Therapeutic Opportunities for Treatment of Human Malignancies Sci. Signal., May 30, 2006; 2006(337): pe25 - pe25. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Melillo and G. L. Semenza Meeting Report: Exploiting the Tumor Microenvironment for Therapeutics. Cancer Res., May 1, 2006; 66(9): 4558 - 4560. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Cancer Research | Clinical Cancer Research |
| Cancer Epidemiology Biomarkers & Prevention | Molecular Cancer Therapeutics |
| Molecular Cancer Research | Cancer Prevention Research |
| Cancer Prevention Journals Portal | Cancer Reviews Online |
| Annual Meeting Education Book | Meeting Abstracts Online |
