| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
ARTICLES |
Department of Pharmacology and Therapeutics, Grace Center Drug Center, Roswell Park Cancer Institute (P.-P.H.L., M.M.I.), Buffalo, New York 14263; Institute of Physiology, National Yang-Ming University (J.J.H.), Taipei, Taiwan; and School of Biological Sciences, University of East Anglia (G.M.), Norwich, Norfolk, United Kingdom
Address all correspondence and requests for reprints to: Dr. Margot M. Ip, Grace Cancer Drug Center, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, New York 14263. E-mail: margot.ip{at}RoswellPark.org
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
|
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Two gelatinases, MMP-2 (72-kDa gelatinase) and MMP-9 (92-kDa
gelatinase), are key proteinases governing the degradation of basement
membrane collagen types IV and V, as well as different types of gelatin
(7). These two gelatinases share structural and catalytic
similarities; however, their gene expression is differentially
regulated, partly due to the distinct structure of the regulatory
elements and promoters in their genes (11, 12, 13). Both MMP-2
and MMP-9 are produced by many cell types, and each is involved in
several cellular events (14, 15, 16, 17, 18, 19, 20, 21, 22). However, in contrast to
MMP-9, whose expression has been implicated in renal development,
macrophage differentiation, atherosclerosis, inflammation, rheumatoid
arthritis, and tumor invasion (15, 16, 17, 18, 19, 20, 21, 22), MMP-2 usually is
expressed constitutively. The production of MMP-9 can be induced by
many factors including the inflammatory cytokine, tumor necrosis
factor-
(TNF) (17, 19, 20, 21, 22, 23). In osteosarcoma-derived OST
cells implanted in nude mice (20) and human myeloblastic
leukemia cells (ML-1) (21), TNFinduced MMP-9 is
associated with invasion. TNF also serves as an autocrine regulator of
PMA-induced expression of MMP-9 and differentiation of HL-60 myeloid
leukemia cells (22). In rheumatoid arthritis, TNF is a key
mediator in stimulating MMP-9 and other inflammatory cytokines
(19, 23, 24) because TNF neutralizing antibodies, or
inhibition of TNF-induced MMP activity using MMP inhibitors, is
effective in its treatment (25, 26, 27, 28).
TNF, which is a multifunctional cytokine, is produced mainly by macrophages but can also be produced by many other cell types in response to physiological or pathological stimuli (29). The original interest in TNF was based on its antitumoral activity in transformed cell types including breast cancer cells (30). In general, nontransfomed cells are resistant to the cytotoxic or cytostatic effects of TNF, but there are some exceptions (31). Our laboratory has demonstrated that TNF, as well as each of its receptors, are differentially expressed throughout mammary gland development (32). TNF also stimulates the growth and branching morphogenesis of normal mammary epithelial cells (MEC) in primary culture (32, 33, 34), and these functions are mediated through the p55 (proliferation, morphogenesis) and p75 (morphogenesis) TNF receptors (32). However, the underlying regulatory mechanism is not known. Because our previous studies suggested a role for gelatinases (MMP-9 and MMP-2)2 and TNF (32, 33, 34, 35) in the proliferation and branching morphogenesis of MEC, we undertook studies to determine whether MMPs might mediate the effects of TNF. First, we examined the effect of TNF on MMP production in MEC. We then used a peptide, which contains the conserved prodomain sequence of MMP, as well as MMP inhibitors (BB-94 and CGS 27023A), to show the involvement of MMPs in TNF-induced growth and branching morphogenesis of MEC. Finally, using a neutralizing antibody against MMP-9, we demonstrated that MMP-9 plays a functionally significant role in tissue remodeling in TNF-induced proliferation and branching morphogenesis in MEC.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
(5 x 106
U/mg) was a gift from Asahi Chemical Industry Co. (Fuji,
Shizuoka, Japan). The prodomain peptide (TMRKPRCGNPDVAN) and control
peptide (TMPKPRSGNPDVAN) were synthesized in the Biopolymer Facility,
Roswell Park Cancer Institute (Buffalo, NY). CGS 30553 (BB-94) and CGS
27023A were provided by Novartis Pharmaceuticals
(Summit, NJ). The MMP-9 antibody used was a previously described
sheep antimouse IgG (15). Normal sheep IgG and goat
antisheep secondary antibody were purchased from Jackson ImmunoResearch Laboratories, Inc. (West Grove, PA).
Nitrocellulose membrane was obtained from Bio-Rad Laboratories, Inc. (Hercules, CA), and ECL Western blotting detection reagents
(RPN 2016 and 2132) were obtained from Amersham Pharmacia Biotech (Arlington Heights, IL).
Animals
Virgin, 50- to 55-day-old, female Sprague Dawley CD rats
(Crl:CDBR), purchased from Charles River Laboratories, Inc. (Wilmington, MA), were used as the source of mammary glands
in all experiments. Female CD2F1 mice, purchased from NCI-Frederick
Cancer Research Facility, Biological Testing Branch (Frederick, MD),
were used to carry the Englebreth-Holm-Swarm sarcoma (EHS) from which
the reconstituted basement membrane (RBM) was prepared
(36). Animals were fed rat or mouse chow diets (Teklad,
Madison, WI), respectively, ad libitum and had free access
to water. Animal rooms were air conditioned and humidity controlled,
with light cycles of 14 h on, 10 h off (rats) or 12 h
on, 12 h off (mice). The care and use of the animals was in
accordance with NIH guidelines and institute animal care and use
committee regulations.
Primary MEC isolation and culture
The procedures for isolation of primary MEC have been described
previously (36). Isolated mammary organoids were
resuspended in ice-cold RBM matrix at a concentration of 1.5 x
106 cells/ml matrix. For each experiment, 200
µl of this cell-RBM suspension were plated on top of 200 µl
solidified RBM in 15.5-mm Falcon plastic multiwell tissue culture
plates (Falcon, Oxnard, CA) and incubated at 37 C for 3 h. After
solidification of the cell-RBM suspension, 1 ml serum-free medium (SFM)
was added to each well. The SFM used in these studies consisted of
phenol red-free DMEM-Ham’s F-12 (1:1, vol:vol) containing 10 µg/ml
insulin, 1 µg/ml progesterone, 1 µg/ml hydrocortisone, 1 µg/ml
PRL, 5 µg/ml transferrin, 5 µM ascorbic acid, 1 mg/ml
fatty acid-free BSA, and 50 µg/ml gentamycin. EGF (0.1 ng/ml) or TNF
(30 or 40 ng/ml) was added where indicated in the text. Cells were
refed with fresh medium twice per week. BB-94, and CGS 27023A were
prepared as stock solutions in dimethyl sulfoxide, and aliquots were
stored at -80 C. Peptides, anti-MMP-9 antibody, normal sheep IgG, and
MMP inhibitors, BB-94 and CGS 27023A, were added to the media
immediately before each feeding. Viable cell number was quantitated in
triplicate wells by the modification of the MTT assay that we described
previously (36). A standard curve was set up using the
newly isolated rat MEC before each experiment. Each experiment was
repeated at least two or three times with cells isolated from different
groups of rats.
Morphological analysis
Morphological development of the MEC organoids was quantitated
by light microscopic observation. Six colony types were classified, as
described previously (33) and as shown in Fig. 2B
: 1)
squamous; 2) end bud (EB)–like lobular; 3) end bud–like multilobular;
4) alveolar (alv)–multilobular; 5) multilobular-ductal; 6) simple
ductal. Squamous colonies are characterized by their concentric swirl
appearance and rust-coloring. End bud-like colonies are rust in color
with either a spherical (lobular) or multilobular appearance and are
composed primarily of immature epithelial cells that show little or no
evidence of functional differentiation. Alveolar colonies are black and
translucent and appear as multilobular colonies without ductal
projections, or as complex colonies with multilobular regions
interconnected by extensive ductal branching. MEC within the alveolar
colonies are composed of morphologically and functionally
differentiated cells organized into a classical alveolar arrangement.
Simple ductal colonies are morphologically differentiated, with ducts
projecting from a small single lobular or multilobular colony. It
should be noted that when MEC are grown in the absence of EGF,
morphological development may vary depending on the batch of RBM that
is used to grow the cells; importantly, however, responsiveness to TNF,
or to other hormones or growth factors, is independent of RBM batch. An
Olympus Corp. CK2 microscope (Olympus Corp.,
New Hyde Park, NY) mounted with a Nikon Fx-35A camera was
used for photography of individual colonies.
|
Western immunoblotting
Samples of media were subjected to electrophoresis on 12%
SDS-polyacrylamide gels, according to the procedure of Laemmli
(38). After electrophoresis, the samples were transferred
to nitrocellulose membrane. The membrane was blocked, washed, and
incubated either with the mouse monoclonal or sheep antimouse MMP-9
antibodies (1:200, vol:vol). After washing, the membrane was incubated
with secondary antibody (1:5000, vol:vol) and subsequently incubated
with streptavidin-peroxidase. Finally, the membrane was incubated with
the ECL detection reagents and then exposed to Kodak x-ray
film (Eastman Kodak Co., Rochester, NY).
Statistics
Data are presented as mean ± SEM. Statistical
significance was evaluated using a one-way ANOVA with the
Student-Newman-Keuls test for pairwise multiple comparisons.
P < 0.05 was judged to be statistically
significant.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
, low levels of a 97-kDa
gelatinase were detected in the control samples. TNF stimulated
secretion of a slightly smaller 95-kDa gelatinase at each time point
tested (Fig. 1A). Both the 97 and 95 kDa gelatinases were identified as
MMP-9 by Western blotting using anti-MMP antibodies. (Fig. 1B). In
other studies, we found that the stimulatory effect of TNF on MMP-9
secretion could be seen as early as day 1 in culture, and both in the
absence or presence of EGF (data not shown). These data indicate that
TNF-induced MMP-9 is an early and continuous event and suggests that
MMP-9 may be involved in TNF-induced proliferation and branching
morphogenesis of MEC. In the presence of TNF, secretion of the 95-kDa
gelatinase was stimulated 2- to 4-fold at each time point examined
(Fig. 1A). MMP-2 activity was also detected in the media (Fig. 1A);
however, TNF had no effect or a slightly inhibitory effect on
MMP-2.
|
Effects of prodomain and control peptides. As shown in Fig. 2A
, TNF increased MEC cell number by
approximately 2-fold, and this increase was completely blocked by the
highest concentration of prodomain peptide. The control peptide, in
which a serine residue was substituted for the cysteine, had no effect
on growth. The prodomain peptide, but not the control peptide, also
blocked TNF-induced morphological differentiation. As seen in Fig. 2, C
and D, TNF stimulated differentiation of end bud colonies to alveolar
colonies, as well as to the complex three dimensional branched
multilobular-ductal alveolar colonies (Figs. 2B and 3); however, this increase was
specifically blocked by the two highest concentrations of the prodomain
peptide. In addition, these concentrations of prodomain peptide
inhibited TNF-induced ductal elongation (Fig. 3, top panel).
Concurrently, TNF suppression of squamous outgrowth was also blocked
(Fig. 2C). These observed effects are consistent with the inhibitory
effect of the prodomain peptide, but not the control peptide on MMP
activity in MEC conditioned medium1.
|
), although BB-94 was considerably more
potent. BB-94, at a concentration of 10-8
–10-5 M, also inhibited
TNF-induced differentiation to alveolar multilobular and
multilobular-ductal colonies (Fig. 4B), as well as ductal elongation
(Fig. 3, middle panel). Although CGS 27023A also inhibited
TNF-induced morphogenesis (Fig. 4C), as well as ductal elongation (data
not shown), it was approximately 100 times less potent than BB-94. In
contrast to the dramatic stimulatory effect of BB-94 and CGS 27023A on
abnormal squamous development observed when MEC organoids were cultured
in medium lacking hydrocortisone1, these drugs did not
suppress the TNF inhibition of abnormal squamous development (Fig. 4, B
and C). Finally, similar to what we found in previous
studies1, after 17 days of culture of MEC with BB-94, this
drug stimulated secretion of MMP-2, MMP-9 and other MMPs in a
concentration-dependent manner (Fig. 5A).
CGS 27023A, however, slightly inhibited MMP secretion at the
concentrations tested (Fig. 5B).
|
|
, anti-MMP-9 antibody (120
µg/ml) modestly inhibited TNF-induced proliferation. At this
concentration, the MMP-9 antibody also inhibited the ability of
TNF to induce differentiation of end bud to alveolar-multilobular
colonies and prevented the TNFinduced formation of the highly
branched multilobular-ductal colonies (Figs. 3, lower panel,
and 6B). MMP-9 antibody at a concentration of 60 µg/ml was also
partly effective in inhibiting TNF-induced morphogenesis (Fig. 6B). In
contrast to the neutralizing MMP-9 antibodies, normal sheep IgG had no
effect on TNF-induced proliferation nor on branching morphogenesis
(Fig. 6, A and C), even at a concentration as high as 200 µg/ml (data
not shown). This result strongly demonstrates that MMP-9 is an
important determinant of TNF-induced proliferation and branching
morphogenesis.
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
), suggesting it may be an activated species.
Similar to our studies, the induction of MMP-9 by TNF was also found in
other cell types (17, 19, 20, 21, 22, 23). In MEC, the induction is an
early event, and demonstrates that the increased MMP-9 messenger RNA,
which is seen within 8 h of addition of TNF to MEC at day 7 of
primary culture (Shea-Eaton, W., P.-P.H. Lee, and M. M. Ip,
unpublished data) is rapidly translated to functional protein. The
highest fold induction of MMP-9 by TNF occurred at a time when MEC were
actively proliferating (day 5) (36) and declined
thereafter; however, TNF stimulation of MMP-9 was observed at all time
points tested. TNF had no or a slightly inhibitory effect on the
secretion of MMP-2, demonstrating the selectivity and specificity of
the response. This result is consistent with other studies (20, 44, 45). Using the prodomain peptide (TMRKPRCGNPDVAN) that was shown to inhibit MMP-2 and MMP-9 activities in MEC1, we found that this prodomain peptide, but not the control peptide1, inhibited TNF-induced proliferation and ductal branching morphogenesis in these cells. This prodomain peptide has also been shown to inhibit cell invasion in other studies (39, 40). These results thus suggest that MMPs are involved in the proliferation and branching morphogenesis stimulated by TNF, although the IC50 of the prodomain peptide was high (5 x 10-4–10-3 M), which may reflect the high MMP activities in our culture, or result from the binding of the peptide to components of the RBM and/or the weak activity of this MMP inhibitor. Park et al. previously demonstrated that this peptide was a relatively weak inhibitor of MMPs (43).
MMP activity in tumor cells and in surrounding stromal tissues is implicated in angiogenesis and tumor progression, invasion, and metastasis (5, 6, 7). Therapeutic intervention via MMP inhibition has shown promise in a number of in vitro and in vivo tumor models, as well as in clinical trials (46, 47, 48, 49, 50, 51, 52). One of the drugs used in our studies, BB-94, is a potent MMP inhibitor that has been shown to block the growth and/or metastases of a number of human and murine cell lines; it also delayed the growth of primary human breast tumors (47, 48, 49, 50, 51, 52). BB-94 inhibited TNF-induced proliferation and ductal branching in MEC, and was much more potent than the prodomain peptide. This result is consistent with our enzyme inhibition assay, which demonstrated that BB-94 is a more potent inhibitor of MMPs than the prodomain peptide1. Although CGS 27023A, another MMP inhibitor, had similar effects as BB-94, it was about 100 times less potent. Finally, in previous studies1, we found that in the absence of hydrocortisone in the culture medium, both BB-94 and CGS 27023A stimulated the formation of abnormal squamous colonies, suggesting the importance of MMP activity in normal mammary alveolar development. The current studies demonstrate that TNF can overcome this abnormal differentiation pathway in an MMP-independent manner. Although the mechanism for this effect is not known, it is possible that TNF-induced changes in cytoskeletal reorganization may play an important role.
MMP inhibitors have also been found to be effective in the treatment of
rheumatoid arthritis, in which TNF plays a major role in the pathology
of this chronic inflammatory disease (7, 28, 53). The
mechanism of this effect, at least in part, is due to the ability of
this class of drugs to inhibit TNF-converting enzyme (TACE), the
enzyme that cleaves membrane TNF, thus blocking secretion of the 17 kDa
soluble pro-inflammatory TNF (53, 54, 55, 56). This beneficial
effect, however, may be negated because MMP inhibitors also inhibit TNF
receptor shedding, resulting in an increased level of both TNF
receptors on the cell surface, with consequent up-regulation of TNF
signaling (53, 57). Thus, a neutralizing anti-TNF antibody
therapy in conjunction with a MMP inhibitor has been suggested in the
treatment of arthritis (53). Importantly, it is unlikely
that the inhibition of TNF-induced proliferation and branching
morphogenesis of MEC by MMP inhibitors as observed in the current study
is due to inhibition of either TNF receptor shedding or secretion of
TNF by any of the drugs tested. First, inhibition of TNF receptor
shedding would be expected to up-regulate, not down-regulate TNF
signaling. Second, although it is possible that BB-94 could inhibit
proliferation and branching morphogenesis by blocking TNF secretion,
the fact that the activity of exogenous TNF was inhibited in our
studies suggests that the biological changes are a direct result of
MMP-9 inhibition, rather than an indirect result of changes in TNF
processing or signaling.
MMP-9 is produced by a variety of normal cells, including mesenchymal, epithelial, endothelial, and inflammatory cells, as well as by tumor cells. Its expression has been correlated with both physiological and pathological processes including renal organogenesis, inflammation, arthritis, atherosclerosis, and tumor cell invasion and metastasis (15, 16, 17, 18, 19, 20, 21, 22). Using a neutralizing antibody against MMP-9 (15), the current studies demonstrate that MMP-9 is required for branching of mammary epithelial organoids in primary culture. MMP-9, but not MMP-2, has also been implicated in in vitro branching morphogenesis of the ureter bud (15). The mechanisms for this effect of MMP-9 remain speculative. In addition to being involved in the degradation of extracellular matrix, MMP-9 may also be implicated in the processing of precusor forms of growth factors and cytokines as well as their receptors, and/or may regulate the release of matrix-associated growth factors. Finally, the formation of branching ducts requires a tightly regulated ratio of tissue inhibitors of metalloproteinases (TIMPs) and MMPs.
In summary, based on the TNF inhibitory effects of synthetic MMP
inhibitors, as well as a specific MMP-9 neutralizing antibody, it can
be concluded that MMP-9 is a major determinant of TNF-induced branching
morphogenesis in MEC. Because recent data in our laboratory demonstrate
that mammary epithelial branching is inhibited in TNF null mice during
puberty (35), it can be proposed that MMP-9 may play a
role in the controlled invasion of the fat pad that occurs during
normal mammary gland development. Furthermore, disruption of MMP-9
regulation may contribute to the invasiveness of breast cancer. Thus,
drugs that can inhibit MMP-9 synthesis and/or activation may show
therapeutic efficacy in breast cancer, although the positive feedback
regulation wherein inhibition of MMP activity by BB-94, but not CGS
27023A results in increased synthesis and/or secretion of MMPs (Fig. 5)
demonstrates that caution is necessary in their application to the
clinic.
|
Acknowledgments |
|---|
|
Footnotes |
|---|
2 Lee PP-H, Hwang J-J, Mead L, Ip MM,
The functional role of matrix metalloproteinases (MMPs) in mammary
epithelial cell development. Manuscript submitted.
Received April 3, 2000.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
and
IL-1 ß selectively induce expression of 92-kDa gelatinase by human
macrophages. J Immunol 157:4159–4165[Abstract]
.
Biochem Biophys Res Commun 171:610–617[CrossRef][Medline]
via
5ß1 integrin in HL-60
cells. J Biol Chem 273:11583–11588 antibodies on synovial cell
IL-1 production in rheumatoid arthritis. Lancet 2:244–247[CrossRef][Medline]
. Eur J Immunol 21:2575–2579[Medline]
(cA2) versus placebo in rheumatoid
arthritis. Lancet 344:1105–1110[CrossRef][Medline]
is cytotoxic to normal, untransformed
mouse and rat embryo fibroblast-like cells. Anticancer Res 9:167–172[Medline]
: a
multifunctional regulator of mammary gland development. Endocrinology 137:4915–4924[Abstract]
. Endocrinology 130:2833–2844[Abstract]
action in normal mammary epithelial cells. Endocrinology 138:3891–3900 knockout mice. Proc Am Assoc Cancer Res 40:161
contributes to increased microvascular
endothelial permeability. Am J Physiol 265:L438–L447
processing in RA synovial membrane cell cultures.
J Clin Invest 97:2833–2841[Medline]
precursor by metalloproteinases. Nature 370:555–557[CrossRef][Medline]
processing by a metalloproteinase inhibitor. Nature 370:558–561[CrossRef][Medline]
receptors in a
human colon adenocarcinoma (Colo 205) cell line. Cancer Res 58:4001–4007This article has been cited by other articles:
 |
|
 |
|
  H.-I. Kwak, T. Gustafson, R. P. Metz, B. Laffin, P. Schedin, and W. W. Porter Inhibition of breast cancer growth and invasion by single-minded 2s Carcinogenesis, February 1, 2007; 28(2): 259 - 266. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Zhang, M. A. Warren, S. F. Shoemaker, and M. M. Ip NF{kappa}B1/p50 Is Not Required for Tumor Necrosis Factor-Stimulated Growth of Primary Mammary Epithelial Cells: Implications for NF{kappa}B2/p52 and RelB Endocrinology, January 1, 2007; 148(1): 268 - 278. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. D. Sternlicht, S. W. Sunnarborg, H. Kouros-Mehr, Y. Yu, D. C. Lee, and Z. Werb Mammary ductal morphogenesis requires paracrine activation of stromal EGFR via ADAM17-dependent shedding of epithelial amphiregulin Development, September 1, 2005; 132(17): 3923 - 3933. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Montesano, P. Soulie, J. A. Eble, and F. Carrozzino Tumour necrosis factor {alpha} confers an invasive, transformed phenotype on mammary epithelial cells J. Cell Sci., August 1, 2005; 118(15): 3487 - 3500. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. B. Lee, J. M. Song, J. E. Lee, J. H. Park, S. J. Kim, S. M. Kang, J. N. Kwon, M. K. Kim, S. I. Roh, and H. S. Yoon Available human feeder cells for the maintenance of human embryonic stem cells Reproduction, December 1, 2004; 128(6): 727 - 735. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Zhang, H. Zhang, L. Lee, and M. M. Ip The Liver-Enriched Inhibitory Protein Isoform of CCAAT/Enhancer-Binding Protein {beta}, But Not Nuclear Factor-{kappa}B, Mediates the Transcriptional Inhibition of {beta}-Casein by Tumor Necrosis Factor-{alpha} Endocrinology, June 1, 2004; 145(6): 2833 - 2844. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W.-N. U. Chen, R. L. Woodbury, L. E. Kathmann, L. K. Opresko, R. C. Zangar, H. S. Wiley, and B. D. Thrall Induced Autocrine Signaling through the Epidermal Growth Factor Receptor Contributes to the Response of Mammary Epithelial Cells to Tumor Necrosis Factor {alpha} J. Biol. Chem., April 30, 2004; 279(18): 18488 - 18496. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.-H. Woo, J.-W. Park, S.-H. Lee, Y.-H. Kim, I. K. Lee, E. Gabrielson, S.-H. Lee, H.-J. Lee, Y.-H. Kho, and T. K. Kwon Dykellic Acid Inhibits Phorbol Myristate Acetate-induced Matrix Metalloproteinase-9 Expression by Inhibiting Nuclear Factor {kappa}B Transcriptional Activity Cancer Res., June 15, 2003; 63(12): 3430 - 3434. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Oya, A. Horiguchi, R. Mizuno, K. Marumo, and M. Murai Increased Activation of CCAAT/Enhancer Binding Protein-{beta} Correlates with the Invasiveness of Renal Cell Carcinoma Clin. Cancer Res., March 1, 2003; 9(3): 1021 - 1027. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Medina, S. Videla, A. Radomski, M. W. Radomski, M. Antolin, F. Guarner, J. Vilaseca, A. Salas, and J.-R. Malagelada Increased activity and expression of matrix metalloproteinase-9 in a rat model of distal colitis Am J Physiol Gastrointest Liver Physiol, January 1, 2003; 284(1): G116 - G122. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Muller, A. Morotti, and C. Ponzetto Activation of NF-{kappa}B Is Essential for Hepatocyte Growth Factor-Mediated Proliferation and Tubulogenesis Mol. Cell. Biol., February 15, 2002; 22(4): 1060 - 1072. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. S. Berleth, P. A. Masso-Welch, L. A. Kazim, M. M. Ip, E. Mihich, and M. J. Ehrke Expression, tissue distribution, and cellular localization of the antiapoptotic TIP-B1 protein J. Leukoc. Biol., June 1, 2001; 69(6): 995 - 1005. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. K. Shea-Eaton, P.-P. H. Lee, and M. M. Ip Regulation of Milk Protein Gene Expression in Normal Mammary Epithelial Cells by Tumor Necrosis Factor Endocrinology, June 1, 2001; 142(6): 2558 - 2568. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||
