| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biochemistry and Biophysics |
Departments of Obstetrics & Gynecology and Cell & Molecular Biology, Northwestern University Medical School, Chicago, Illinois 60611 [S. M. E., M. S. S.]; Program in Toxicology, College of Pharmacy and Department of Cell Biology & Physiology, School of Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131 [J. M. H., M. B., L. G. H.]; and Division of Environmental and Occupational Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota 55455 [J. K. W., E. V. W., L. G. H.]
 |
ABSTRACT |
|---|
 Top ABSTRACT INTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
|
INTRODUCTION |
|---|
|
TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
The mechanisms by which EGF receptor-dependent signaling contributes to ovarian cancer metastatic potential are poorly understood. Ovarian epithelial tumor cell metastasis often involves dissociation of tumor cells from the primary lesions, dissemination and attachment to the peritoneal mesothelial cell wall, and modification of the underlying connective tissue barrier through proteolysis to promote invasion and growth (11, 12, 13) . Serine protease and MMP activity generated or used by ovarian cancer cells appears to contribute to many, if not all, of these metastatic steps (13) . Several lines of evidence suggest that MMP-9 is involved in tumor metastasis. Experimental findings indicate a relationship between elevated MMP-9 expression and metastatic potential in vivo for melanoma (14) and prostate tumors (15) , and experimental metastasis is suppressed in MMP-9-deficient mice (16) . In ovarian tumors, the ratio of MMP-9:MMP-2 is elevated in tumor tissue compared with normal ovaries (17) , and elevated levels of MMP-9 protein have been detected in invasive epithelial ovarian carcinoma patient specimens (18) . Moreover, primary ovarian tumor cells in short-term culture produce MMP-9; however, expression is lost with time in culture, indicating that extracellular factors, such as EGF, regulate ovarian cancer cell production of proteolytic activity in a paracrine fashion (19) .
In support of this hypothesis, we demonstrated previously that EGF stimulates production of both urokinase-type plasminogen activator and MMP-9 in several ovarian tumor cell lines (12) . Cell lines that display EGF-stimulated MMP-9 protein expression are more invasive than non-MMP-9-producing cell lines, and anticatalytic antibodies to MMP-9 strongly inhibit EGF-stimulated invasion. In this work, we investigate the contributions of several EGF receptor-mediated signaling pathways to the regulation of MMP-9 production and localization, junctional dissolution, cell migration, and in vitro invasion of OVCA 429 ovarian tumor cells. Our results demonstrate that MMP-9 binding to the cell surface is regulated by intracellular PI3K activity and provide mechanistic insight into the downstream effectors of EGF-stimulated ovarian tumor cell migration and invasion.
|
MATERIALS AND METHODS |
|---|
|
TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
-32P]ATP was acquired from New England Nuclear (Boston, MA). The construct pGEX-2T-c-Jun (1–79 amino acids) was the kind gift of Dr. Daniel Mueller (Department of Medicine, University of Minnesota). PGEX-3X-ATF-2 was the generous gift of Dr. Benoit Dérijard (Center de Biochimie, Nice, France). GST fusion proteins were expressed and purified as described previously (20)
.
Cell Culture and Treatment.
Ovarian carcinoma cell line OVCA 429 was generously provided by Dr. Robert Bast, Jr. (M. D. Anderson Cancer Center, Houston, TX) and grown as described previously (12)
. For experiments using pharmacological inhibitors, cells were pretreated for the indicated times, and every treatment condition received an equal concentration of DMSO (not in excess of 0.25% for any experiment). Incubation with inhibitors did not compromise cell viability, as determined by trypan blue exclusion. For experiments involving growth factor addition, OVCA 429 cells were placed into MEM containing 0.1% (w/v) BSA for 24 h prior to growth factor addition (12)
.
Western Blot Analysis and Kinase Assays.
Control and treated cells were washed with ice-cold PBS and harvested in lysis buffer [62.5 mM Tris-HCl (pH 6.8), 2% SDS, 10% glycerol, 50 mM DTT, and 0.1% w/v bromphenol blue]. Cell lysates were clarified at (10,000 x g at 4°C for 10 min), and 10 µg of total cell lysate were resolved by electrophoresis through 10% SDS-polyacrylamide gel, transferred to polyvinylidene difluoride membranes (Millipore Corp., Bedford, MA), and probed with the indicated antibodies according to the vendor’s instructions and as described previously (20
, 21)
. JNK and p38 activity was measured by the immunocomplex assay described previously (20)
. Substrate phosphorylation was detected by autoradiography and quantified using a Bio-Rad Model GS-700 imaging densitometer.
In Vitro Invasion and Cell Motility.
Cells were plated onto Matrigel-coated well inserts (11 µg/filter; 8 µm pore size; Becton Dickinson, Bedford, MA) in serum-free medium and incubated at 37°C for 4 h to allow for cellular adherence and spreading on the filter. The inhibitors LY294002 (10 µM), SB202190 (10 µM), PD98059 (50 µM), or DMSO vehicle control (0.25%) were then added directly to wells and incubated for an additional hour before administration of EGF (100 nM). Cells were allowed to invade through the Matrigel over a period of 72 h at 37°C under standard culture conditions. Noninvading cells were removed from the top of the wells with a cotton swab tip, followed by fixation and staining with the Diff-Quick staining kit (Fisher Scientific). All experiments were completed in triplicate, and at least 20 fields/filter were counted. Evaluation of colony dispersion (cell scattering) was performed as described previously (20)
. Results shown are representative of at least three independent experiments.
Zymogram Analysis.
OVCA 429 cells were serum deprived for 24 h prior to growth factor treatment in fresh serum-free medium. Samples of conditioned medium collected from control and growth factor-treated cell cultures were analyzed for proteinase activity by substrate-gel zymography as described previously (12)
. Briefly, equal total protein from experimental samples was resolved on 8 or 10% SDS-polyacrylamide gels containing 0.1% gelatin. After electrophoresis, gels were washed with 2.5% Triton X-100 for 30 min at room temperature and then incubated with substrate buffer (50 mM Tris, 0.2 M NaCl, 5 mM CaCl2, and 0.02% Brij, pH 7.6) 24–48 h at 37°C. Proteinase activity is visualized as zones of clearance in a Coomassie blue-stained gel. Results shown are representative of a minimum of three independent experiments.
TIMP-1 ELISA.
TIMP-1 ELISA kits were obtained from Amersham (Arlington Heights, IL) and performed according to the manufacturer’s protocol. Fifty µg of protein were tested to estimate the concentration of TIMP-1 in cell lysates.
Analysis of MMP Cell Surface Association.
Cells were grown to 80–90% confluency on 10-cm tissue culture dishes before switching to fresh serum-free medium. Cells were washed with PBS and given 5 ml of fresh serum-free medium containing LY294002 (10 µM), SB202190 (10 µM), PD98059 (50 µM), or DMSO vehicle control (0.25% v/v). After a 1-h incubation, EGF (100 nM) was added directly to cells. In some experiments, purified human MMP-9 (80 ng/ml) was added. After a 36-h incubation, cells were washed two times with 5 ml of PBS, and then surface proteins were labeled with 2.5 ml of 500 µg/ml sulfo-NHS Biotin (Pierce) in PBS under gentle shaking at 4°C for 30 min. Cells were washed two times in 5 ml of PBS and then incubated with 5 ml of 100 mM glycine/PBS (pH 7.2) for an additional 20 min under gentle shaking at 4°C. Cells were washed three times in 5 ml of PBS and then lysed with 1 ml of buffered detergent [50 mM sodium phosphate (pH 8.0), 300 mM NaCl, 1% NP40, 1 µg/ml aprotinin, 1 µM pepstatin, 10 µM leupeptin, and 10 µM E64]. Lysates were collected with a cell scraper and clarified (10,000 x g at 4°C for 10 min). Protein concentrations were calculated using the Bio-Rad DC protein assay kit and diluted to a concentration of 750 µg/ml. One ml of diluted lysate was added to 40 µl of ImmunoPure immobilized monomeric avidin gel (Pierce) in a 1.5-ml screw cap tube and incubated overnight at 4°C on a rotator. Gels were washed by centrifugation (10,000 x g at 4°C for 30 s), followed by aspiration of supernatant and addition of 1 ml of fresh lysis buffer. Washes were repeated for a total of five times. Forty µl of 10 mM free D-Biotin/PBS (Pierce) were added to compete bound protein overnight at 4°C. Thirty-µl aliquots were analyzed by gelatin substrate zymography as described above.
Immunofluorescence.
OVCA 429 cells were seeded in a Lab Tek II chamber slide system (Nalge Nunc International, Naperville, IL). After 1 day of growth, cultures were switched to serum-free medium. Cell chambers received 350 µl of 10 µM LY294002, 50 µM PD98059, or 10 µM SB202190 in fresh serum-free medium or DMSO load control. After 2 h, EGF was administered to chamber wells at the concentrations and times indicated in the figure legends. For detection of desmosomal junctions, cells were fixed for 2 min in ice-cold, dehydrated methanol and then blocked in 1.5% BSA in PBS containing calcium and magnesium overnight at 4°C. A chicken anti-plakoglobin antibody (ab1407; generous gift of Dr. K. Green, Northwestern University) was added at a 1:200 dilution for 1 h at 37°C. Cells were washed four times in PBS containing calcium and magnesium and then incubated with FITC-labeled goat antichicken antibody (AVES Labs, Inc., Tigard, OR) at 1:500 dilution for 1 h at 37°C. For detection of adherens junctions, cells were fixed for 2 min in ice-cold methanol, incubated at 37°C for 2 h with a 1:5 dilution (PBS) of hybridoma supernatant containing anti-ß catenin primary antibody clone 5H10 (generous gift of Dr. M. Wheelock, University of Toledo, Toledo, OH), washed three times with PBS, and then incubated with a 1:500 dilution of sheep antimouse secondary antibody tagged with fluorescein (Boehringer Mannheim, Indianapolis, IN) for 1 h at 37°C. For detection of cell surface-associated MMP-9, cells were fixed with 3.7% formaldehyde/PBS for 7 min and then washed two times for 5 min in PBS in a Coplin jar. Cell chambers were incubated with 100 µl of rabbit IgG or anti-MMP-9 AB805 rabbit polyclonal (1:150) for 
4 h at 37°C and then washed three times for 5 min with PBS. Chambers were incubated with 100 µl of a 1:250 dilution of donkey antirabbit fluorescein conjugate secondary antibody (Chemicon) for 1 h at 37°C before washing three times for 5 min with PBS. Slides were set under coverslip using fresh gelvatol (Sigma) and analyzed using a Zeiss Photomicroscope (Thornwood, NY). Images were digitized using Zeiss imaging software and compiled using Adobe Photoshop Software.
|
RESULTS |
|---|
|
TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
. EGF-stimulated ERK activation in OVCA 429 cells is sustained for an extended period of time (>4 h), as has been reported in other epithelial models, including human keratinocytes (20
, 22)
and mammary epithelial tumor cells (23)
. In contrast, EGF-dependent stimulation of JNK and p38 in OVCA 429 cells is transient and maximal at 15 min after EGF addition (Fig. 1, B and C)
.
|
. Both basal and EGF-dependent AKT/PKB activation was ablated by two mechanistically distinct pharmacological inhibitors of PI3K catalytic activity, LY294002 and wortmannin (Fig. 2A
; data not shown). PI3K has been reported to be an upstream activator of both JNK and ERK in fibroblasts (24, 25, 26)
, thereby providing a potential mechanism for EGF-dependent JNK activation in OVCA 429 cells. To determine whether PI3K activity is involved in EGF-stimulated MAPK activation, cells were treated with LY294002 or wortmannin prior to EGF treatment. Exposure to LY294002 or wortmannin did not interfere with EGF stimulation of the ERK, JNK, or p38 MAPK cascades (Fig. 2, B–D
; data not shown). This demonstrates that LY294002 is an effective and selective inhibitor of PI3K activity, as reported previously (27)
, and that the following observations of PI3K-dependent responses in OVCA 429 cells are not attributable to indirect disruption of the MAPK signaling cascades.
|
. PD98059 prevents activation of MEK1, thereby selectively inhibiting the ERK pathway (28)
, and SB202190 is a direct inhibitor of p38 catalytic activity (29)
. Inhibition of PI3K by LY294002 or wortmannin, p38 by SB202190, or ERK activation by PD98059 was sufficient to reduce invasion to near basal levels, indicating that multiple EGF-stimulated signal transduction pathways contribute to an invasive response in ovarian cancer cells.
|
, a response that represents both increased cell migration and disruption of cell:cell adhesive junctions. Consistent with the in vitro invasion assay, administration of the PI3K inhibitor LY294002 or the MAPK inhibitors SB202190 or PD98059 effectively impeded cell scattering (Fig. 4, F–H)
. In contrast, divergence in EGF-dependent signaling requirements was observed for disruption of desmosomal and adherens junctions (Fig. 5)
. EGF treatment promotes redistribution of plakoglobin (-catenin; Fig. 5B
) and ß-catenin (Fig. 5G)
from the cell periphery to the cytoplasm. Inhibition of PI3K activity by LY294002 prior to ligand stimulation did not alter EGF-dependent disruption of either desmosomal junctions (Fig. 5C)
or adherens junctions (Fig. 5H)
. In contrast, inhibition of EGF-stimulated ERK and p38 activation by PD98059 or SB202190, respectively, eliminated EGF-dependent disruption of desmosomal (Fig. 5, D and E)
and adherens (Fig. 5, I and J)
junctions. These data strongly implicate MAPK activity in EGF-induced junctional dissolution, whereas PI3K activity appears to play a role in other aspects of migration and invasion.
|
|
. These data indicate that multiple kinase pathways converge to regulate MMP-9 expression. In contrast, MMP-2 expression was refractory to EGF stimulation of OVCA 429 cells (12)
; however, inhibition of p38 activity in control or stimulated cells consistently depressed MMP-2 levels in CM, suggesting a role for this MAPK in basal MMP-2 production.
|
. In contrast, inhibition of PI3K and p38 activation minimally disrupted EGF-stimulated TIMP-1 expression. These results illustrate differences in the EGF-dependent signaling requirements for MMP-9 and TIMP-1 induction.
|
, Lanes 2 and 4). Although inhibition of ERK activation by PD98059 and p38 activity by SB202190 reduces EGF-stimulated MMP-9 expression to near control levels in CM (Fig. 7B
, upper panel, Lanes 1, 4, and 5), considerable pro-MMP-9 binding to the cell surface was retained under these conditions (Fig. 7B
, lower panel, Lanes 1, 4, and 5). In contrast, inhibition of EGF-induced PI3K signaling abolished pro-MMP-9 association with the cell surface (Fig. 7B
, Lane 3), indicating that PI3K activity is an important regulator of gelatinase association with the cell surface. The doublet of cell surface gelatinase activity (Fig. 7B
, bracket) was not inhibited by the zinc(2+) chelating agent 1,10-phenanthrolene, suggesting that it is likely a cell surface serine protease (i.e., plasmin; data not shown). EGF stimulation of MMP-9 cell surface association was confirmed by immunofluorescence (Fig. 8B)
, and MMP-9 binding was not detected on the surface of cells treated with PI3K inhibitors (Fig. 8C)
.
|
|
, Lanes 5 and 6) was as effective as exposure to inhibitors before EGF addition (Fig. 9A
, Lane 4) with regard to disruption of cell surface gelatinase association. However, addition of LY294002 2 h prior to collection of surface proteins had no effect on cell surface MMP-9 levels (Fig. 9A
, Lane 7). To address whether pro-MMP-9 binding is regulated by extracellular concentrations of the enzyme, an excess of exogenous purified human MMP-9 was added to cells under different treatment conditions (Fig. 9B)
. Addition of pro-MMP-9 to control cells did not promote enzyme binding to the cell surface (Fig. 9B
, Lane 2) or recover binding to cells stimulated with EGF and concurrently treated with LY294002 (Fig. 9B
, Lane 4). Together, these data indicate that EGF stimulated pro-MMP-9 membrane association involves a PI3K-sensitive pathway.
|
|
DISCUSSION |
|---|
|
TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
In this study, we identified divergence in the signaling requirements for specific elements of a migratory or invasive response. EGF-induced motility as assayed by colony dispersion and in vitro invasion through a reconstituted basement membrane was suppressed by selective inhibitors of PI3K, p38, and the ERK activating kinase MEK1 (Figs. 3
and 4
), confirming the reported involvement of MAPKs and PI3K in cell migration. In contrast, PI3K activity was not required for disruption of cell:cell junctions (Fig. 5)
or EGF-stimulated TIMP-1 induction (Table 1)
. The signaling requirements for junctional dissolution may be cell type and growth factor specific. For example, Potempa and Ridley (35)
reported that Ras-dependent activation of MAPK and PI3K was required for hepatocyte growth factor-stimulated disruption of adherens junctions in Madin-Darby canine kidney cells, whereas dissolution of desmosomes and tight junctions occurred through a Ras-independent signaling pathway. In findings similar to our own, breakdown of VE-cadherin-mediated adhesion by vascular endothelial growth factor in endothelial cell monolayers requires MAPK, but not PI3K, activity (36)
, and EGF-induced morphological changes involving disruption of adherens junctions was reported to be independent of PI3K activity in colon carcinoma cells (37)
. The findings illustrated in Fig. 5
indicate that PI3K activity is not required for EGF-dependent dissolution of either adherens or desmosomal junctions in OVCA 429 cells but identifies a requirement for MAPK activity.
Although the role of ERK and p38 MAPKs in MMP-9 gene expression has been well documented (20, 21, 22
, 38, 39, 40)
, involvement of PI3K in EGF-stimulated MMP-9 production has not been studied extensively. Reddy et al. (40)
reported recently that PI3K inhibition only partially blocks EGF induction of MMP-9 expression in breast epithelial cells, whereas both invasion and MMP-9 production are significantly dependent on MEK signaling. Once expressed, recent evidence suggests that (pro)MMP-9 can bind to the cell surface through interactions the 
2 chain of type IV collagen, the putative tumor suppressor RECK, or the transmembrane matrix receptor CD44 (30
, 32
, 41)
. However, little is known of mechanisms that regulate MMP-9 surface binding, including cell surface association in response to growth factor stimulation.
Our work provides insight into growth factor regulation of MMP-9 expression and cell surface association. We found that basal and EGF-induced MMP-9 protein expression involves both PI3K and MAPK signaling (Fig. 6)
, whereas EGF-induced expression of the inhibitor, TIMP-1, is regulated predominantly by MEK/ERK signaling (Table 1)
. In contrast, EGF-dependent cell surface association of MMP-9 is highly PI3K dependent (Figs. 7
8
9)
. pro-MMP-9 membrane association appears to be a directed event; addition of exogenous pro-MMP-9 does not induce pro-MMP-9 binding to membranes from control or PI3K-inhibited cells (Fig. 9B
, Lanes 2 and 4). These data suggest that EGF stimulation promotes the cell surface expression of an unidentified pro-MMP-9 binding component(s). As PI3K has been implicated in intracellular membrane and protein trafficking events (42)
, PI3K-mediated trafficking of pro-MMP-9 or its binding component to the cell surface may be a potential mechanism of gelatinase association. Investigations are currently under way to address the identity of the EGF-regulated pro-MMP-9 binding component(s) and the potential role of PI3K regulation of posttranslational trafficking events.
|
FOOTNOTES |
|---|
1 This study was supported by NIH Grants CA86985 (to M. S. S.), GM08061 (to S. M. E.), and CA72498 (to E. V. W.) and in part by Grants AR42989 and DE12458 (to L. G. H.). 
2 To whom requests for reprints should be addressed, at University of New Mexico Health Sciences Center, 2502 Marble NE, NRPH B-80, Albuquerque, NM 87131. Phone: (505) 272-2482; Fax: (505) 272-6749; E-mail: lghudson{at}unm.edu
3 The abbreviations used are: EGF, epidermal growth factor; ERK, extracellular signal-regulated kinase; GST, glutathione S-transferase; JNK, c-jun NH2-terminal kinase; MAPK, mitogen-activated protein kinase; MEK, mitogen-activated protein kinase kinase; MMP, matrix metalloproteinase; PI3K, phosphatidylinositol 3-kinase; TIMP, tissue inhibitor of metalloproteinase; CM, conditioned medium.
Received 7/31/00. Accepted 12/29/00.
|
REFERENCES |
|---|
|
TopABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
and progesterone in urine of ovarian cancer patients. Anticancer Res., 14: 2119-123, 1994.[Medline]
This article has been cited by other articles:
|
|
 |
|
  K. D. Cowden Dahl, J. Symowicz, Y. Ning, E. Gutierrez, D. A. Fishman, B. P. Adley, M. S. Stack, and L. G. Hudson Matrix Metalloproteinase 9 Is a Mediator of Epidermal Growth Factor-Dependent E-Cadherin Loss in Ovarian Carcinoma Cells Cancer Res., June 15, 2008; 68(12): 4606 - 4613. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Tran, P. Rousselle, P. Nokelainen, S. Tallapragada, N. T. Nguyen, E. F. Fincher, and M. P. Marinkovich Targeting a Tumor-Specific Laminin Domain Critical for Human Carcinogenesis Cancer Res., April 15, 2008; 68(8): 2885 - 2894. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. R. Radjabi, K. Sawada, S. Jagadeeswaran, A. Eichbichler, H. A. Kenny, A. Montag, K. Bruno, and E. Lengyel Thrombin Induces Tumor Invasion through the Induction and Association of Matrix Metalloproteinase-9 and {beta}1-Integrin on the Cell Surface J. Biol. Chem., February 1, 2008; 283(5): 2822 - 2834. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Okawa, C. Z. Michaylira, J. Kalabis, D. B. Stairs, H. Nakagawa, C. Andl, C. N. Johnstone, A. J. Klein-Szanto, W. S. El-Deiry, E. Cukierman, et al. The functional interplay between EGFR overexpression, hTERT activation, and p53 mutation in esophageal epithelial cells with activation of stromal fibroblasts induces tumor development, invasion, and differentiation Genes & Dev., November 1, 2007; 21(21): 2788 - 2803. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Y. Zhou, Y. L. Pon, and A. S. T. Wong Synergistic Effects of Epidermal Growth Factor and Hepatocyte Growth Factor on Human Ovarian Cancer Cell Invasion and Migration: Role of Extracellular Signal-Regulated Kinase 1/2 and p38 Mitogen-Activated Protein Kinase Endocrinology, November 1, 2007; 148(11): 5195 - 5208. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H.-W. Lo, S.-C. Hsu, W. Xia, X. Cao, J.-Y. Shih, Y. Wei, J. L. Abbruzzese, G. N. Hortobagyi, and M.-C. Hung Epidermal Growth Factor Receptor Cooperates with Signal Transducer and Activator of Transcription 3 to Induce Epithelial-Mesenchymal Transition in Cancer Cells via Up-regulation of TWIST Gene Expression Cancer Res., October 1, 2007; 67(19): 9066 - 9076. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Pu, C. D. McCaig, L. Cao, Z. Zhao, J. E. Segall, and M. Zhao EGF receptor signalling is essential for electric-field-directed migration of breast cancer cells J. Cell Sci., October 1, 2007; 120(19): 3395 - 3403. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A.R.M. Ruhul Amin, M. H. Uddin Biswas, T. Senga, G.-S. Feng, R. Kannagi, M. L. Agarwal, and M. Hamaguchi A role for SHPS-1/SIRP{alpha} in Concanavalin A-dependent production of MMP-9 Genes Cells, September 1, 2007; 12(9): 1023 - 1033. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. D. Cowden Dahl, R. Zeineldin, and L. G. Hudson PEA3 Is Necessary for Optimal Epidermal Growth Factor Receptor-Stimulated Matrix Metalloproteinase Expression and Invasion of Ovarian Tumor Cells Mol. Cancer Res., May 1, 2007; 5(5): 413 - 421. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Symowicz, B. P. Adley, K. J. Gleason, J. J. Johnson, S. Ghosh, D. A. Fishman, L. G. Hudson, and M. S. Stack Engagement of Collagen-Binding Integrins Promotes Matrix Metalloproteinase-9-Dependent E-Cadherin Ectodomain Shedding in Ovarian Carcinoma Cells Cancer Res., March 1, 2007; 67(5): 2030 - 2039. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S.-S. Liau, A. Jazag, and E. E. Whang HMGA1 Is a Determinant of Cellular Invasiveness and In vivo Metastatic Potential in Pancreatic Adenocarcinoma Cancer Res., December 15, 2006; 66(24): 11613 - 11622. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Morgillo, J. K. Woo, E. S. Kim, W. K. Hong, and H.-Y. Lee Heterodimerization of Insulin-like Growth Factor Receptor/Epidermal Growth Factor Receptor and Induction of Survivin Expression Counteract the Antitumor Action of Erlotinib. Cancer Res., October 15, 2006; 66(20): 10100 - 10111. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. N. Mon, H. Hasegawa, A. A. Thant, P. Huang, Y. Tanimura, T. Senga, and M. Hamaguchi A Role for Focal Adhesion Kinase Signaling in Tumor Necrosis Factor-{alpha}-Dependent Matrix Metalloproteinase-9 Production in a Cholangiocarcinoma Cell Line, CCKS1. Cancer Res., July 1, 2006; 66(13): 6778 - 6784. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Ahmed, S. Maines-Bandiera, M. A. Quinn, W. G. Unger, S. Dedhar, and N. Auersperg Molecular pathways regulating EGF-induced epithelio-mesenchymal transition in human ovarian surface epithelium Am J Physiol Cell Physiol, June 1, 2006; 290(6): C1532 - C1542. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Oku, E. Sasabe, E. Ueta, T. Yamamoto, and T. Osaki Tight Junction Protein Claudin-1 Enhances the Invasive Activity of Oral Squamous Cell Carcinoma Cells by Promoting Cleavage of Laminin-5 {gamma}2 Chain via Matrix Metalloproteinase (MMP)-2 and Membrane-Type MMP-1. Cancer Res., May 15, 2006; 66(10): 5251 - 5257. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Shukla, T. F. Barrett, K. I. Nakayama, K. Nakayama, B. T. Mossman, and K. M. Lounsbury Transcriptional up-regulation of MMP12 and MMP13 by asbestos occurs via a PKC{delta}-dependent pathway in murine lung FASEB J, May 1, 2006; 20(7): 997 - 999. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-H. Choi, K.-C. Choi, N. Auersperg, and P. C.K. Leung Gonadotropins Activate Proteolysis and Increase Invasion through Protein Kinase A and Phosphatidylinositol 3-Kinase Pathways in Human Epithelial Ovarian Cancer Cells. Cancer Res., April 1, 2006; 66(7): 3912 - 3920. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Ning, R. Zeineldin, Y. Liu, M. Rosenberg, M. S. Stack, and L. G. Hudson Down-regulation of Integrin {alpha}2 Surface Expression by Mutant Epidermal Growth Factor Receptor (EGFRvIII) Induces Aberrant Cell Spreading and Focal Adhesion Formation Cancer Res., October 15, 2005; 65(20): 9280 - 9286. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Jorda, D. Olmeda, A. Vinyals, E. Valero, E. Cubillo, A. Llorens, A. Cano, and A. Fabra Upregulation of MMP-9 in MDCK epithelial cell line in response to expression of the Snail transcription factor J. Cell Sci., August 1, 2005; 118(15): 3371 - 3385. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. H. Thaker, S. Yazici, M. B. Nilsson, K. Yokoi, R. Z. Tsan, J. He, S.-J. Kim, I. J. Fidler, and A. K. Sood Antivascular Therapy for Orthotopic Human Ovarian Carcinoma through Blockade of the Vascular Endothelial Growth Factor and Epidermal Growth Factor Receptors Clin. Cancer Res., July 1, 2005; 11(13): 4923 - 4933. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Zahradka, G. Harding, B. Litchie, S. Thomas, J. P. Werner, D. P. Wilson, and N. Yurkova Activation of MMP-2 in response to vascular injury is mediated by phosphatidylinositol 3-kinase-dependent expression of MT1-MMP Am J Physiol Heart Circ Physiol, December 1, 2004; 287(6): H2861 - H2870. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y.-A. Choi, H.-K. Lim, J.-R. Kim, C.-H. Lee, Y.-J. Kim, S.-S. Kang, and S.-H. Baek Group IB Secretory Phospholipase A2 Promotes Matrix Metalloproteinase-2-mediated Cell Migration via the Phosphatidylinositol 3-Kinase and Akt Pathway J. Biol. Chem., August 27, 2004; 279(35): 36579 - 36585. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Miyata, T. Sato, M. Yano, and A. Ito Activation of protein kinase C {beta}II/{varepsilon}-c-Jun NH2-terminal kinase pathway and inhibition of mitogen-activated protein/extracellular signal-regulated kinase 1/2 phosphorylation in antitumor invasive activity induced by the polymethoxy flavonoid, nobiletin Mol. Cancer Ther., July 1, 2004; 3(7): 839 - 847. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. S. Herbst and P. A. Bunn Jr. Targeting the Epidermal Growth Factor Receptor in Non-Small Cell Lung Cancer Clin. Cancer Res., December 1, 2003; 9(16): 5813 - 5824. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M.-S. Kim, E.-J. Lee, H.-R. C. Kim, and A. Moon p38 Kinase Is a Key Signaling Molecule for H-Ras-induced Cell Motility and Invasive Phenotype in Human Breast Epithelial Cells Cancer Res., September 1, 2003; 63(17): 5454 - 5461. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X.-Q. Wang, P. Sun, and A. S. Paller Ganglioside GM3 Inhibits Matrix Metalloproteinase-9 Activation and Disrupts Its Association with Integrin J. Biol. Chem., July 3, 2003; 278(28): 25591 - 25599. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. A. Ward, L. Huang, H. Guo, S. Ghatak, and B. P. Toole Perturbation of Hyaluronan Interactions Inhibits Malignant Properties of Glioma Cells Am. J. Pathol., May 1, 2003; 162(5): 1403 - 1409. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. D. Andl, T. Mizushima, H. Nakagawa, K. Oyama, H. Harada, K. Chruma, M. Herlyn, and A. K. Rustgi Epidermal Growth Factor Receptor Mediates Increased Cell Proliferation, Migration, and Aggregation in Esophageal Keratinocytes in Vitro and in Vivo J. Biol. Chem., January 10, 2003; 278(3): 1824 - 1830. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Choe, J. K. Park, L. Jouben-Steele, T. J. Kremen, L. M. Liau, H. V. Vinters, T. F. Cloughesy, and P. S. Mischel Active Matrix Metalloproteinase 9 Expression Is Associated with Primary Glioblastoma Subtype Clin. Cancer Res., September 1, 2002; 8(9): 2894 - 2901. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Salcedo, M. Martins-Green, B. Gertz, J. J. Oppenheim, and W. J. Murphy Combined Administration of Antibodies to Human Interleukin 8 and Epidermal Growth Factor Receptor Results in Increased Antimetastatic Effects on Human Breast Carcinoma Xenografts Clin. Cancer Res., August 1, 2002; 8(8): 2655 - 2665. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Edme, J. Downward, J.-P. Thiery, and B. Boyer Ras induces NBT-II epithelial cell scattering through the coordinate activities of Rac and MAPK pathways J. Cell Sci., June 15, 2002; 115(12): 2591 - 2601. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 O. Alper, E. S. Bergmann-Leitner, T. A. Bennett, N. F. Hacker, K. Stromberg, and W. G. Stetler-Stevenson Epidermal Growth Factor Receptor Signaling and the Invasive Phenotype of Ovarian Carcinoma Cells J Natl Cancer Inst, September 19, 2001; 93(18): 1375 - 1384. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Sun, L. Wenger, C. E. Brinckerhoff, R. R. Misra, and H. S. Cheung Basic Calcium Phosphate Crystals Induce Matrix Metalloproteinase-1 through the Ras/Mitogen-activated Protein Kinase/c-Fos/AP-1/Metalloproteinase 1 Pathway. INVOLVEMENT OF TRANSCRIPTION FACTOR BINDING SITES AP-1 AND PEA-3 J. Biol. Chem., January 4, 2002; 277(2): 1544 - 1552. [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 |
