Previous Article | Next Article 
Molecular and Cellular Biology, March 2003, p. 1581-1589, Vol. 23, No. 5
0270-7306/03/$08.00+0 DOI: 10.1128/MCB.23.5.1581-1589.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.
Distinct Mechanisms of Receptor and Nonreceptor Tyrosine Kinase Activation by Reactive Oxygen Species in Vascular Smooth Muscle Cells: Role of Metalloprotease and Protein Kinase C-
Gerald D. Frank,1 Mizuo Mifune,1 Tadashi Inagami,1 Motoi Ohba,2 Terukatsu Sasaki,3 Shigeki Higashiyama,4 Peter J. Dempsey,5 and Satoru Eguchi1*
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232,1
Institute of Molecular Oncology, Showa University, Tokyo 142-8555,2
Department of Biochemistry, Sapporo Medical University, Sapporo 060-8556,3
Department of Biochemistry, School of Allied Health Science, Osaka University Faculty of Medicine, Osaka 565-0871, Japan,4
Pacific Northwest Research Institute, Seattle, Washington 981225
Received 24 July 2002/
Returned for modification 4 September 2002/
Accepted 2 December 2002

ABSTRACT
Reactive oxygen species (ROS) are implicated in cardiovascular
diseases. ROS, such as H
2O
2, act as second messengers to activate
diverse signaling pathways. Although H
2O
2 activates several
tyrosine kinases, including the epidermal growth factor (EGF)
receptor, JAK2, and PYK2, in vascular smooth muscle cells (VSMCs),
the intracellular mechanism by which ROS activate these tyrosine
kinases remains unclear. Here, we identified two distinct signaling
pathways required for receptor and nonreceptor tyrosine kinase
activation by H
2O
2 involving a metalloprotease-dependent generation
of heparin-binding EGF-like growth factor (HB-EGF) and protein
kinase C (PKC)-

activation, respectively. H
2O
2-induced EGF receptor
tyrosine phosphorylation was inhibited by a metalloprotease
inhibitor, whereas the inhibitor had no effect on H
2O
2-induced
JAK2 tyrosine phosphorylation. HB-EGF neutralizing antibody
inhibited H
2O
2-induced EGF receptor phosphorylation. In COS-7
cells expressing an HB-EGF construct tagged with alkaline phosphatase,
H
2O
2 stimulates HB-EGF production through metalloprotease activation.
By contrast, dominant negative PKC-

transfection inhibited H
2O
2-induced
JAK2 phosphorylation but not EGF receptor phosphorylation. Dominant
negative PYK2 inhibited H
2O
2-induced JAK2 activation but not
EGF receptor activation, whereas dominant negative PKC-

inhibited
PYK2 activation by H
2O
2. These data demonstrate the presence
of distinct tyrosine kinase activation pathways (PKC-

/PYK2/JAK2
and metalloprotease/HB-EGF/EGF receptor) utilized by H
2O
2 in
VSMCs, thus providing unique therapeutic targets for cardiovascular
diseases.

INTRODUCTION
Reactive oxygen species (ROS), including superoxide anion and
hydrogen peroxide (H
2O
2), are known to act as second messengers
(
21,
41). ROS activate a wide variety of serine-threonine and
tyrosine kinases, which are key regulatory proteins of signal
transduction pathways important in mediating cellular growth,
apoptosis, survival, migration, and aging (
22,
35). An increasing
body of evidence suggests that ROS and tyrosine kinase play
prominent roles in the development and progression of the cardiovascular
remodeling associated with hypertension, atherosclerosis, and
restenosis after balloon angioplasty (
2,
29).
ROS activate nonreceptor tyrosine kinases JAK2 (1, 59), PYK2/CAKß (25), and Src (11, 67) and receptor tyrosine kinases epidermal growth factor (EGF) receptor (23, 53, 67) and platelet-derived growth factor receptor (34) in vascular smooth muscle cells (VSMCs) as well as other cell lines. A few studies have shown an inhibition of ligand-stimulated receptor tyrosine kinase induced by ROS (33), suggesting a dominant role for ROS as a tyrosine kinase activator. Among tyrosine kinases activated by ROS, the EGF receptor and JAK2 are of particular interest in VSMCs. A G-protein-coupled receptor (GPCR) agonist, angiotensin II (AngII), has been shown to utilize ROS to activate the EGF receptor in VSMCs (23, 66). The activation of the EGF receptor by AngII or thrombin appears to be required for extracellular signal-regulated kinase (ERK) activation and the subsequent growth of VSMCs (15, 17, 19, 38). By contrast, ROS-dependent JAK2 activation is required for AngII-induced cytokine induction (56) and thrombin-induced heat shock protein induction (47) in VSMCs. Thus, ROS-dependent activation of the EGF receptor and JAK2 could mediate two distinct functions in VSMCs, such as growth and inflammatory responses, respectively. However, whether ROS activate the EGF receptor and JAK2 through distinct mechanisms remains unknown.
Recently, it has become apparent that the EGF receptor is also a part of the signaling networks activated by stimuli that do not directly interact with this receptor. These stimuli include agonists that specifically bind to other membrane receptors and environmental stressors (6). Collectively, EGF receptor transactivation by these factors is employed in a wide array of biological signaling responses (32, 45), which may participate in several disease processes (4, 42, 50). In this regard, EGF receptor transactivation is a current topic of signal transduction research.
ROS have been proposed to exert their effects through targeting the cysteine regions of the active sites of tyrosine phosphatases, which in turn activates tyrosine kinases (21). In fact, H2O2 has been shown to inhibit the dephosphorylation of the EGF receptor through the inhibition of a tyrosine phosphatase (39). Protein kinase C-
(PKC-
) is also implicated in ROS-dependent activation of tyrosine kinases, such as c-Abl and Src. H2O2 stimulates binding between PKC-
and c-Abl where the activation of c-Abl is dependent on PKC-
activation (61). Interestingly, H2O2-induced activation of PKC-
is reported to be independent from tyrosine phosphatase inhibition (68). Alternatively, ROS may activate a tyrosine kinase by generating growth factors, such as heparin-binding EGF-like growth factor (HB-EGF), through metalloprotease cleavage. ROS production and metalloprotease-dependent HB-EGF generation are implicated in EGF receptor transactivation initiated through several GPCRs (9, 52). Our group has shown that both mechanisms are indispensable for EGF receptor transactivation induced by AngII in VSMCs (14, 23). In addition, a metalloprotease, ADAM17 (TACE), was reported to require PKC-
activation to generate HB-EGF (37).
In this study, we examined the hypothesis that the activation of receptor and nonreceptor protein tyrosine kinases by ROS utilizes distinct signal transduction mechanisms involving a metalloprotease or PKC-
. We found that a metalloprotease-dependent shedding of HB-EGF is required for H2O2-induced EGF receptor transactivation but not for JAK2 activation. By contrast, PKC-
is required for H2O2-induced JAK2 activation but not for EGF receptor transactivation. The activation of JAK2 but not of the EGF receptor also requires PYK2 activation. Taken together, our findings provide a unique example of two distinct signaling pathways that mediate ROS-dependent tyrosine kinase activation in vascular cells.

MATERIALS AND METHODS
Reagents.
BB2116 was kindly provided by Helen Mills (British Biotech).
CGS27023, GM6001, AG1478, and rottlerin were purchased from
Calbiochem. H
2O
2, AngII,
N-acetylcysteine, and poly[Glu
80-Tyr
20]
were purchased from Sigma. Antibodies were purchased from the
following sources: phospho-JAK2, phospho-EGF receptor, and phospho-PYK2,
BioSource International; JAK2, Upstate Biotechnology; EGF receptor,
PKC-

, PKC-

, and PKC-ß1, Santa Cruz Biotechnology;
PYK2, Transduction Laboratories; and neutralizing human HB-EGF,
R & D Systems.
Cell culture.
VSMCs were prepared from thoracic aortas of Sprague-Dawley rats (18). Subcultured cells from passages 3 to 12 were used and showed 99% positive immunostaining with smooth muscle
-actin antibody (Sigma). Human aortic VSMCs were obtained from Clonetics and subcultured according to the manufacturer's manual. For experiments, VSMCs at 80 to 90% confluency were used after serum depletion for 3 days.
Adenovirus transfection.
The generation of kinase-inactive PKC-
, PKC-
, PKC-ß1, and PYK2/CAKß mutant-encoded adenovirus constructs is described in detail elsewhere (36, 48). VSMCs were infected with adenovirus for 2 days as previously described (17).
Immunoprecipitation and immunoblotting.
After stimulation, cells were lysed with ice-cold immunoprecipitation buffer (150 mM NaCl, 20 mM Tris [pH 7.5], 1% Triton X-100, 5 mM EDTA, 50 mM NaF, 10% [vol/vol] glycerol, 10 mg of leupeptin, 10 µg of aprotinin, and 10 µg of phenylmethylsulfonyl fluoride). The lysates were centrifuged, and the supernatant was immunoprecipitated with antibody and protein A/G agarose at 4°C for 16 h (19). Cell or immunoprecipitation lysates were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to a nitrocellulose membrane, and immunoblotted as described previously (19).
HB-EGF shedding assay.
To examine the release of soluble HB-EGF, COS-7 cells were transfected with the alkaline phosphatase (AP)-tagged HB-EGF (HB-EGF-AP) plasmid (63) by a transferrin receptor-operated transfer (8, 58) with TransFast transfection reagent (Promega). Forty-eight hours after transfection, the medium was changed to Dulbecco modified Eagle medium without phenol red and cells were stimulated with H2O2. HB-EGF-AP secreted into the medium was assessed by measuring AP activity (63).
PKC-
kinase assay.
Kinase activity of PKC-
was measured by an immune complex kinase assay as described previously (26, 61). After stimulation, cells were lysed with a buffer containing 50 mM HEPES (pH 7.5), 0.5% NP-40, 150 mM NaCl, 1 mM EDTA, 1 mM EGTA, 1 mM sodium orthovanadate, 1 mM dithiothreitol, 1 mM NaF, 2 mM phenylmethylsulfonyl fluoride, and 10 µg each of pepstatin and leupeptin/ml. Cell lysates were centrifuged, and the supernatant was immunoprecipitated with anti-PKC-
antibody for 2.5 h. The kinase assay was performed with a kinase assay buffer (20 mM Tris-HCl [pH 7.5], 10 mM MgCl2, 2.5 µCi of [
-32P]ATP, and a substrate, 200 µg of histone H1/ml) incubated for 15 min at 30°C.
PYK2 kinase assay.
PYK2 kinase activity was measured by an immune complex kinase assay as described previously (25). In brief, the cell lysates were centrifuged and the supernatant was immunoprecipitated with anti-PYK2 antibody for 2.5 h at 4°C. After being washed, the immune complexes were incubated with or without H2O2 for 10 min at room temperature in the kinase buffer (100 mM sodium HEPES [pH 7.6], 60 mM MgCl2, 2 mM MnCl2, 0.2 mM Na3VO4, 0.2% Triton X-100). Afterwards, the lysates were incubated at room temperature in kinase buffer containing 0.25 mg of poly[Glu80-Tyr20] and 2.5 µCi of [
-32P]ATP for 15 min. The reaction mixture was spotted onto Whatman 3MM paper, washed, and then measured by liquid scintillation counting.

RESULTS
H2O2 stimulates EGF receptor activation and JAK2 activation.
The activation of the EGF receptor by H
2O
2 was assessed by a
phospho-specific antibody. This antibody selectively recognizes
the EGF receptor only when Tyr
1068 (a Grb2 binding site) is
autophosphorylated. Also, the activation of JAK2 was assessed
by a phospho-specific antibody that selectively recognizes Tyr
1007/1008 dually phosphorylated JAK2. These tyrosine residues are believed
to be autophosphorylation sites, with Tyr
1007 phosphorylation
being essential for JAK2 kinase activity (
57). The specificities
of these antibodies have been established previously (
23). As
shown in Fig.
1A, H
2O
2 time-dependently stimulated the phosphorylation
of the EGF receptor and JAK2, with maximal phosphorylation occurring
at 10 min. As shown in Fig.
1B, H
2O
2 concentration-dependently
stimulated the phosphorylation of the EGF receptor and JAK2,
with maximal phosphorylation occurring at H
2O
2 concentrations
of 2 to 20 µM. These data suggest that the EGF receptor
and JAK2 represent ROS-sensitive tyrosine kinases in VSMCs.
Involvement of metalloprotease-dependent HB-EGF generation in H2O2-induced EGF receptor activation.
To determine whether EGF receptor transactivation by H
2O
2 requires
metalloprotease-dependent generation of an EGF receptor ligand,
VSMCs were pretreated with a metalloprotease inhibitor (BB2116)
and stimulated with H
2O
2. BB2116 and a structurally related
compound, batimastat, have been shown to selectively inhibit
the processing of several EGF receptor ligand precursors (
5,
12,
13). It has previously been shown that BB2116 has no nonspecific
effect on EGF receptor signals stimulated by EGF (
14). As shown
in Fig.
2, H
2O
2-induced EGF receptor activation was concentration-dependently
inhibited by BB2116 but JAK2 activation by H
2O
2 was unaffected
by BB2116. Other metalloprotease inhibitors, CGS27023 and GM6001
(10 µM each, 30-min pretreatments), also inhibited H
2O
2-induced
EGF receptor activation but had no effect on JAK2 activation
(data not shown).
It has previously been shown that an HB-EGF neutralizing antibody
effectively antagonizes AngII-induced EGF receptor transactivation
in VSMCs (
14). As shown in Fig.
3A, H
2O
2-induced EGF receptor
activation was markedly inhibited by the HB-EGF neutralizing
antibody. Since the detection of endogenous EGF receptor ligand
generation has proven difficult (
14), we utilized the HB-EGF-AP
expression system, an established assay, to measure the ectodomain
shedding of EGF receptor ligands. H
2O
2 time-dependently stimulated
HB-EGF-AP release into the culture medium at as early as 10
min in COS-7 cells transfected with HB-EGF-AP plasmid, and BB2116
almost completely inhibited HB-EGF-AP generation in response
to H
2O
2 (Fig.
3B). To confirm H
2O
2-induced EGF receptor tyrosine
kinase activation, we examined the effect of AG1478, an EGF
receptor kinase inhibitor (
44). It has previously been shown
that AG1478 specifically inhibits EGF receptor-mediated signal
transduction in VSMCs (
14,
15,
17,
19). AG1478 (250 nM, 30-min
pretreatment) markedly inhibited H
2O
2-induced EGF receptor activation,
whereas this inhibitor had no specific effect on JAK2 activation
by H
2O
2 (data not shown). These data clearly implicate metalloprotease-dependent
HB-EGF generation as a mechanism for H
2O
2-induced EGF receptor
activation.
JAK2 activation but not EGF receptor activation requires PKC-
.
H
2O
2 has been shown to induce PKC-

activation (
40), which may
in turn activate tyrosine kinases (
61). PKC-

is also implicated
in the ectodomain shedding of HB-EGF (
37). Given these findings,
we investigated whether PKC-

was involved in either JAK2 or
EGF receptor activation by H
2O
2. VSMCs were pretreated with
a PKC-

inhibitor, rottlerin (
31). The conditions required for
the inhibition of PKC-

function in VSMCs have been established
previously (
26). As shown in Fig.
4A, rottlerin (1 to 10 µM)
concentration-dependently inhibited JAK2 phosphorylation by
H
2O
2 in VSMCs. Figure
4B and C show that 10 µM rottlerin
markedly inhibited H
2O
2-induced JAK2 activation but not H
2O
2-induced
EGF receptor activation. A potent endogenous ROS inducer, AngII
(
30), produces intracellular H
2O
2 in the 10 to 100 nM range
in VSMCs (
64), which may mimic the exogenous addition of H
2O
2 as shown in Fig.
1A. Our group has previously reported that
AngII-induced JAK2 activation requires PKC-

(
26) and is not
blocked by a metalloprotease inhibitor, BB2116 (
14), in VSMCs.
Another study has shown that AngII-induced JAK2 activation requires
ROS production in VSMCs (
56). As shown in Fig.
4D, AngII-induced
JAK2 activation was markedly inhibited by an antioxidant,
N-acetylcysteine,
in our VSMCs. Also, it has previously been reported that AngII-induced
transactivation of the EGF receptor requires ROS (
23) as well
as HB-EGF production through a metalloprotease (
14) in VSMCs.
As shown in Fig.
4D, rottlerin had no inhibitory effect on AngII-induced
EGF receptor transactivation, confirming that this pathway is
independent from the JAK2 pathway activated by AngII. Taken
together, these data suggest that AngII utilizes these two distinct
pathways through ROS production in VSMCs, supporting the pathophysiological
relevance of our findings.
To further clarify the role of PKC-

in ROS-dependent JAK2 activation,
we transfected VSMCs with adenovirus encoding a kinase-deficient
PKC-

mutant that acts as a dominant negative PKC-

(
48). The
specificity of this mutant has been shown previously (
26). Several
control studies using adenovirus encoding LacZ or vector alone
also showed that the transfection of adenovirus (up to a multiplicity
of infection [MOI] of 100) had no nonspecific effects in VSMCs
(
17,
24,
26). As shown in Fig.
5A and B, dominant negative PKC-
transfection concentration-dependently inhibited H
2O
2-induced
JAK2 activation but not H
2O
2-induced EGF receptor activation.
Moreover, control studies using VSMCs transfected with kinase-inactive
PKC-

and PKC-ß1 revealed no inhibitory effect on H
2O
2-stimulated
JAK2 phosphorylation (Fig.
5C). In addition, H
2O
2 (20 µM,
10-min stimulation) significantly stimulated PKC-

activity in
VSMCs (2.49 [±0.09]-fold increase in activity;
P 
0.05;
n = 4) as measured by an immune complex kinase assay. These
results strongly suggest that PKC-

is required for H
2O
2-induced
JAK2 activation but not for H
2O
2-induced EGF receptor activation.
JAK2 activation but not EGF receptor activation requires PYK2.
PYK2/CAKß is a ROS-sensitive tyrosine kinase (
25),
and our group has recently demonstrated that this kinase is
required for AngII-induced JAK2 activation in VSMCs (
26). PYK2
is also implicated in EGF receptor transactivation by GPCRs
(
3). Therefore, we determined whether PYK2 plays a role in H
2O
2-induced
activation of the EGF receptor and JAK2. VSMCs were transfected
with adenovirus encoding a kinase-deficient PYK2 mutant, K457A
(
36). This mutant acts as a dominant negative PYK2 in VSMCs
(
24). As shown in Fig.
6A, kinase-deficient PYK2 mutant transfection
markedly inhibited H
2O
2-induced JAK2 activation but not EGF
receptor activation. Our group has previously shown that the
treatment of VSMCs with H
2O
2 enhances PYK2 kinase activity (
25).
Thus, we further determined whether H
2O
2 directly activated
PYK2 by measuring in vitro PYK2 kinase activity. However, H
2O
2 did not activate PYK2 kinase activity in vitro (data not shown),
indicating that PYK2 is not a direct target of H
2O
2.
PYK2 Tyr
402 is a major autophosphorylation site of PYK2. Our
group has previously shown that H
2O
2 induces PYK2 Tyr
402 phosphorylation
by using a phospho-specific antibody (
25). To determine whether
PYK2 activation by H
2O
2 is regulated by PKC-

, we examined the
effect of PKC-

inhibitors on PYK2 Tyr
402 phosphorylation. As
shown in Fig.
6B, dominant negative PKC-

transfection markedly
inhibited the phosphorylation of PYK2 induced by H
2O
2. We also
observed similar inhibition by rottlerin (data not shown). These
data suggest that a PKC-

-sensitive tyrosine kinase, PYK2, is
required for the activation of JAK2 by H
2O
2 but not for EGF
receptor activation in VSMCs.

DISCUSSION
The significant finding reported in the present study is that
ROS utilize distinct signaling mechanisms to mediate the activation
of receptor and nonreceptor tyrosine kinases. Specifically,
a metalloprotease-dependent cleavage of HB-EGF is required for
H
2O
2-induced EGF receptor transactivation but not for JAK2 activation
whereas PKC-

is required for H
2O
2-induced PYK2/JAK2 activation
and not for EGF receptor transactivation, as illustrated in
Fig.
7. We believe that this is the first example showing that
ROS activate tyrosine kinases through distinct mechanisms in
the same cell culture system.
Here, we report that H
2O
2 stimulates EGF receptor transactivation
via metalloprotease-dependent HB-EGF cleavage. This observation
uncovers a previously unknown mechanism by which ROS activate
a receptor tyrosine kinase. In support of this notion, our group
has shown that both metalloprotease and ROS are required for
EGF receptor transactivation induced by a GPCR agonist, AngII
(
14,
23). Although the metalloprotease responsible for HB-EGF
generation induced by ROS has not been identified, both matrix
metalloproteases (
62,
69) and ADAM family metalloproteases (
4,
37,
42) are implicated in the ectodomain shedding of HB-EGF
that is stimulated by various agonists. A thiol group from a
cysteine residue in the inhibitory prodomains of these metalloproteases
interacts with zinc in their catalytic domains. ROS may oxidize
electrophilic thiol groups and disrupt the cysteine-zinc bond,
leading to the activation of the metalloproteases. In fact,
H
2O
2 was shown to enhance ADAM17 activity and ADAM17-mediated
ectodomain shedding (
70). Therefore, it is interesting to test
whether ROS activate metalloprotease directly. However, to the
best of our knowledge, no reports have been published of studies
that have directly measured the shedding activity toward proHB-EGF
by using isolated membranes. Thus, to examine the direct activation
of metalloprotease by ROS, further information is required regarding
the identification of the metalloprotease responsible for HB-EGF
generation and/or establishment of the assay to measure metalloprotease
activity toward proHB-EGF in isolated membranes.
Alternatively, ROS may modulate intracellular signals such as c-Src and ERK, which may indirectly activate the metalloprotease responsible for HB-EGF generation. The contribution of the ERK cascade to HB-EGF and transforming growth factor-
generation has been reported previously (20, 27, 65). However, the ERK cascade is unlikely to mediate HB-EGF generation by H2O2 in VSMCs. This is because the ERK cascade exists downstream of EGF receptor transactivation in H2O2-stimulated VSMCs (23). c-Src is involved in EGF receptor transactivation by GPCRs (3, 46, 66), and c-Src appears to exist upstream of HB-EGF release (51). Moreover, H2O2-induced EGF receptor transactivation was inhibited by a selective Src inhibitor, PP2, in endothelial cells (7). The role of c-Src in mediating HB-EGF-dependent EGF receptor transactivation by H2O2 is under current investigation.
Our findings presented here strongly suggest the requirement of PKC-
for JAK2 activation by H2O2. In the present study, we have used rottlerin as a PKC-
inhibitor because it is commonly used as a selective inhibitor of this PKC isoform. In fact, our group has shown that this inhibitor blocks the translocation of PKC-
toward the membrane stimulated by AngII in VSMCs and that it also inhibits the autophosphorylation of human recombinant PKC-
in vitro (26). In contrast, two recent publications reported a failure of PKC-
inhibition by rottlerin in a kinase assay using a synthetic substrate and one of the publications reported that rottlerin showed additional inhibitory effects besides PKC-
inhibition (10, 60). To further evaluate the involvement of PKC-
in JAK2 activation by H2O2, we utilized kinase-inactive PKC mutants and showed that only the PKC-
mutant inhibited JAK2 activation. This is in line with the recent finding that PKC-
is required for JAK2 activation induced by AngII (26), a well-established ROS inducer (30), in VSMCs. In addition, several reports indicate that H2O2 stimulates PKC-
activity in various cell types (40, 49). In this study, we also found that H2O2 could stimulate PKC-
activity in VSMCs. In addition, PKC-
was previously shown to be required for HB-EGF production, possibly through the activation of ADAM9 (37). However, our present findings rather eliminate the role of PKC-
in H2O2-induced EGF receptor activation. This is in good agreement with previous findings by our group that PKC does not mediate EGF receptor transactivation induced by AngII (19).
VSMCs normally express PYK2 that is activated by ROS or AngII through ROS production (16, 25). It has been shown that PYK2 function is indispensable for several AngII-induced signaling pathways and subsequent hypertrophy in VSMCs (24, 54). Specifically, PYK2 is constitutively associated with JAK2 and is required for JAK2 activation by AngII (26). Although PYK2 is implicated in EGF receptor transactivation in fibroblasts (3), this may not be the case for EGF receptor transactivation in VSMCs (66). Here, we found that JAK2 activation but not EGF receptor activation by H2O2 requires PYK2, which appears to be downstream of PKC-
. Interestingly, it was demonstrated that H2O2 stimulates PKC-
and c-Abl association, where c-Abl is activated by a PKC-
-dependent mechanism (61). Thus, the possibility that JAK2 or PYK2 is a substrate with which PKC-
is capable of associating should be considered. PYK2 and its related tyrosine kinase FAK share a common structure with conserved important motifs (43, 55). Recently, FAK was shown to be involved in AngII-induced growth-promoting responses in cultured VSMCs (28). Although our present findings together with previous findings showing an interaction between PYK2 and JAK2 in VSMCs strongly suggest a critical role for PYK2 in mediating ROS-dependent JAK2 activation, it is possible that dominant negative PYK2 may interfere with the FAK function together with PYK2 function. Therefore, further studies are needed to examine the role of FAK in JAK2 activation.
In the present study, we recognized that most approaches that interfered with H2O2-dependent activation did not result in complete inhibition. Thus, both EGF receptor activation and JAK2 activation by ROS could involve additional pathways independent from the pathways identified in this study. In this regard, Src family kinase-dependent pathways have been proposed to mediate JAK2 activation (1) or EGF receptor activation by ROS (7, 66). Also, ROS are believed to stimulate tyrosine phosphorylation by the inhibition of tyrosine phosphatases via the cysteine residues in the active site regions of these enzymes (21). Knebel et al. (39) in fact demonstrated that H2O2 could inhibit the dephosphorylation of the EGF receptor through the inhibition of tyrosine phosphatases. Thus, future research should be conducted to determine whether a tyrosine phosphatase or Src kinase is involved in one or both mechanisms of tyrosine kinase activation by ROS in VSMCs.
In conclusion, we have shown that ROS utilize distinct signal transduction mechanisms to activate nonreceptor and receptor protein tyrosine kinases in VSMCs. This important finding may lead to the selective inhibition of various distinct ROS functions that may sufficiently prevent or attenuate several cardiovascular-related diseases.

ACKNOWLEDGMENTS
We thank Kunie Eguchi and Trinita Fitzgerald for their excellent
technical assistance.
This work was supported by National Institute of Health training grant HL07323 and a United Negro College Fund/Merck postdoctoral science research fellowship (G. Frank), by an American Heart Association Scientist Development Grant and a Vanderbilt University Diabetes Center Pilot & Feasibility Proposal (S. Eguchi), and in part by the research grants HL58205, DK20593, and CA68485 from the National Institute of Health (T. Inagami).

FOOTNOTES
* Corresponding author. Mailing address: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146. Phone: (615) 322-4334. Fax: (615) 322-3201. E-mail:
satoru.eguchi{at}vanderbilt.edu.


REFERENCES
1 - Abe, J., and B. C. Berk. 1999. Fyn and JAK2 mediate Ras activation by reactive oxygen species. J. Biol. Chem. 274:21003-21010.[Abstract/Free Full Text]
2 - Abe, J., and B. C. Berk. 1998. Reactive oxygen species as mediators of signal transduction in cardiovascular disease. Trends Cardiovasc. Med. 8:59-64.[CrossRef]
3 - Andreev, J., M. L. Galisteo, O. Kranenburg, S. K. Logan, E. S. Chiu, M. Okigaki, L. A. Cary, W. H. Moolenaar, and J. Schlessinger. 2001. Src and Pyk2 mediate G-protein-coupled receptor activation of epidermal growth factor receptor (EGFR) but are not required for coupling to the mitogen-activated protein (MAP) kinase signaling cascade. J. Biol. Chem. 276:20130-20135.[Abstract/Free Full Text]
4 - Asakura, M., M. Kitakaze, S. Takashima, Y. Liao, F. Ishikura, T. Yoshinaka, H. Ohmoto, K. Node, K. Yoshino, H. Ishiguro, H. Asanuma, S. Sanada, Y. Matsumura, H. Takeda, S. Beppu, M. Tada, M. Hori, and S. Higashiyama. 2002. Cardiac hypertrophy is inhibited by antagonism of ADAM12 processing of HB-EGF: metalloproteinase inhibitors as a new therapy. Nat. Med. 8:35-40.[CrossRef][Medline]
5 - Brown, C., K. Meise, G. Plowman, R. Coffey, and P. Dempsey. 1998. Cell surface ectodomain cleavage of human amphiregulin precursor is sensitive to a metalloprotease inhibitor. J. Biol. Chem. 273:17258-17268.[Abstract/Free Full Text]
6 - Carpenter, G. 1999. Employment of the epidermal growth factor receptor in growth factor-independent signaling pathways. J. Cell Biol. 146:697-702.[Abstract/Free Full Text]
7 - Chen, K., J. A. Vita, B. C. Berk, and J. F. Keaney. 2001. c-Jun N-terminal kinase activation by hydrogen peroxide in endothelial cells involves SRC-dependent epidermal growth factor receptor transactivation. J. Biol. Chem. 276:16045-16050.[Abstract/Free Full Text]
8 - Cheng, P. 1996. Receptor ligand-facilitated gene transfer: enhancement of liposome-mediated gene transfer and expression by transferrin. Hum. Gene Ther. 7:275-282.[Medline]
9 - Cunnick, J. M., J. F. Dorsey, T. Standley, J. Turkson, A. J. Kraker, D. W. Fry, R. Jove, and J. Wu. 1998. Role of tyrosine kinase activity of epidermal growth factor receptor in the lysophosphatidic acid-stimulated mitogen-activated protein kinase pathway. J. Biol. Chem. 273:14468-14475.[Abstract/Free Full Text]
10 - Davies, S. P., H. Reddy, M. Caivano, and P. Cohen. 2000. Specificity and mechanism of action of some commonly used protein kinase inhibitors. Biochem. J. 351:95-105.[CrossRef][Medline]
11 - Devary, Y., R. A. Gottlieb, T. Smeal, and M. Karin. 1992. The mammalian ultraviolet response is triggered by activation of src tyrosine kinases. Cell 71:1081-1091.[CrossRef][Medline]
12 - Dong, J., L. K. Opresko, P. J. Dempsey, D. A. Lauffenburger, R. J. Coffey, and H. S. Wiley. 1999. Metalloprotease-mediated ligand release regulates autocrine signaling through the epidermal growth factor receptor. Proc. Natl. Acad. Sci. USA 96:6235-6240.[Abstract/Free Full Text]
13 - Dong, J., and H. S. Wiley. 2000. Trafficking and proteolytic release of epidermal growth factor receptor ligands are modulated by their membrane-anchoring domains. J. Biol. Chem. 275:557-564.[Abstract/Free Full Text]
14 - Eguchi, S., P. J. Dempsey, G. D. Frank, E. D. Motley, and T. Inagami. 2001. Activation of MAP kinases by angiotensin II in vascular smooth muscle cells: metalloprotease-dependent EGF receptor activation is required for ERK and p38 MAP kinase, but not for JNK. J. Biol. Chem. 276:7957-7962.[Abstract/Free Full Text]
15 - Eguchi, S., H. Iwasaki, Y. Hirata, J. D. Frank, E. D. Motley, T. Yamakawa, K. Numaguchi, and T. Inagami. 1999. Epidermal growth factor receptor is indispensable for c-Fos expression and protein synthesis by angiotensin II. Eur. J. Pharmacol. 376:203-206.[CrossRef][Medline]
16 - Eguchi, S., H. Iwasaki, T. Inagami, K. Numaguchi, T. Yamakawa, E. D. Motley, K. M. Owada, F. Marumo, and Y. Hirata. 1999. Involvement of PYK2 in angiotensin II signaling of vascular smooth muscle cells. Hypertension 33:201-206.[Abstract/Free Full Text]
17 - Eguchi, S., H. Iwasaki, E. D. Motley, G. D. Frank, H. Ueno, K. Eguchi, F. Marumo, Y. Hirata, and T. Inagami. 1999. Intracellular signaling of angiotensin II-induced p70 S6 kinase phosphorylation at Ser411 in vascular smooth muscle cells: possible requirement of EGF receptor, RAS, ERK, and AKT. J. Biol. Chem. 274:36843-36852.[Abstract/Free Full Text]
18 - Eguchi, S., T. Matsumoto, E. D. Motley, H. Utsunomiya, and T. Inagami. 1996. Identification of an essential signaling cascade for mitogen-activated protein kinase activation by angiotensin II in cultured rat vascular smooth muscle cells. Possible requirement of Gq-mediated p21ras activation coupled to a Ca2+/calmodulin-sensitive tyrosine kinase. J. Biol. Chem. 271:14169-14175.[Abstract/Free Full Text]
19 - Eguchi, S., K. Numaguchi, H. Iwasaki, T. Matsumoto, T. Yamakawa, H. Utsunomiya, E. D. Motley, H. Kawakatsu, K. M. Owada, Y. Hirata, F. Marumo, and T. Inagami. 1998. Calcium-dependent epidermal growth factor receptor transactivation mediates the angiotensin II-induced mitogen-activated protein kinase activation in vascular smooth muscle cells. J. Biol. Chem. 273:8890-8896.[Abstract/Free Full Text]
20 - Fan, H., and R. Derynck. 1999. Ectodomain shedding of TGF-alpha and other transmembrane proteins is induced by receptor tyrosine kinase activation and MAP kinase signaling cascades. EMBO J. 18:6962-6972.[CrossRef][Medline]
21 - Finkel, T. 1998. Oxygen radicals and signaling. Curr. Opin. Cell Biol. 10:248-253.[CrossRef][Medline]
22 - Finkel, T., and N. J. Holbrook. 2000. Oxidants, oxidative stress and the biology of ageing. Nature 408:239-247.[CrossRef][Medline]
23 - Frank, G. D., S. Eguchi, T. Inagami, and E. D. Motley. 2001. N-acetylcysteine inhibits angiotensin II-mediated activation of extracellular signal-regulated kinase and epidermal growth factor receptor. Biochem. Biophys. Res. Commun. 280:1116-1119.[CrossRef][Medline]
24 - Frank, G. D., S. Eguchi, E. D. Motley, T. Sasaki, and T. Inagami. 2001. Unique regulation of c-Jun N-terminal kinase by PYK2/CAK-beta in angiotensin II-stimulated vascular smooth muscle cells. Biochem. Biophys. Res. Commun. 286:692-696.[CrossRef][Medline]
25 - Frank, G. D., E. D. Motley, T. Inagami, and S. Eguchi. 2000. PYK2/CAKbeta represents a redox-sensitive tyrosine kinase in vascular smooth muscle cells. Biochem. Biophys. Res. Commun. 270:761-765.[CrossRef][Medline]
26 - Frank, G. D., S. Saito, E. D. Motley, T. Sasaki, M. Ohba, and T. Inagami. 2002. Requirement of Ca2+ and PKCdelta for Janus kinase 2 activation by angiotensin II: involvement of PYK2. Mol. Endocrinol. 16:367-377.[Abstract/Free Full Text]
27 - Gechtman, Z., J. L. Alonso, G. Raab, D. E. Ingber, and M. Klagsbrun. 1999. The shedding of membrane-anchored heparin-binding epidermal-like growth factor is regulated by the Raf/mitogen-activated protein kinase cascade and by cell adhesion and spreading. J. Biol. Chem. 274:28828-28835.[Abstract/Free Full Text]
28 - Govindarajan, G., D. M. Eble, P. A. Lucchesi, and A. M. Samarel. 2000. Focal adhesion kinase is involved in angiotensin II-mediated protein synthesis in cultured vascular smooth muscle cells. Circ. Res. 87:710-716.[Abstract/Free Full Text]
29 - Griendling, K. K., D. Sorescu, and M. Ushio-Fukai. 2000. NAD(P)H oxidase: role in cardiovascular biology and disease. Circ. Res. 86:494-501.[Abstract/Free Full Text]
30 - Griendling, K. K., F. M. Ushio, B. Lassegue, and R. W. Alexander. 1997. Angiotensin II signaling in vascular smooth muscle. New concepts. Hypertension 29:366-373.
31 - Gschwendt, M., H. J. Muller, K. Kielbassa, R. Zang, W. Kittstein, G. Rincke, and F. Marks. 1994. Rottlerin, a novel protein kinase inhibitor. Biochem. Biophys. Res. Commun. 199:93-98.[CrossRef][Medline]
32 - Gschwind, A., E. Zwick, N. Prenzel, M. Leserer, and A. Ullrich. 2001. Cell communication networks: epidermal growth factor receptor transactivation as the paradigm for interreceptor signal transmission. Oncogene 20:1594-1600.[CrossRef][Medline]
33 - Hansen, L. L., Y. Ikeda, G. S. Olsen, A. K. Busch, and L. Mosthaf. 1999. Insulin signaling is inhibited by micromolar concentrations of H2O2. J. Biol. Chem. 274:25078-25084.[Abstract/Free Full Text]
34 - Heeneman, S., J. Haendeler, Y. Saito, M. Ishida, and B. C. Berk. 2000. Angiotensin II induces transactivation of the platelet-derived growth factor beta receptor. J. Biol. Chem. 275:15926-15932.[Abstract/Free Full Text]
35 - Irani, K. 2000. Oxidant signaling in vascular cell growth, death, and survival: a review of the roles of reactive oxygen species in smooth muscle and endothelial cell mitogenic and apoptotic signaling. Circ. Res. 87:179-183.[Abstract/Free Full Text]
36 - Ishino, M., H. Aoto, H. Sasaski, R. Suzuki, and T. Sasaki. 2000. Phosphorylation of Hic-5 at tyrosine 60 by CAKbeta and Fyn. FEBS Lett. 474:179-183.[CrossRef][Medline]
37 - Izumi, Y., M. Hirata, H. Hasuwa, R. Iwamoto, T. Umata, K. Miyado, Y. Tamai, T. Kurisaki, A. Sehara-Fujisawa, S. Ohno, and E. Mekada. 1998. A metalloprotease-disintegrin, MDC9/meltrin-g/ADAM9 and PKCd are involved in TPA-induced ectodomain shedding of membrane-anchored heparin-binding EGF-like growth factor. EMBO J. 17:7260-7272.[CrossRef][Medline]
38 - Kalmes, A., B. R. Vesti, G. Daum, J. A. Abraham, and A. W. Clowes. 2000. Heparin blockade of thrombin-induced smooth muscle cell migration involves inhibition of epidermal growth factor (EGF) receptor transactivation by heparin-binding EGF-like growth factor. Circ. Res. 87:92-98.[Abstract/Free Full Text]
39 - Knebel, A., H. J. Rahmsdorf, A. Ullrich, and P. Herrlich. 1996. Dephosphorylation of receptor tyrosine kinases as target of regulation by radiation, oxidants or alkylating agents. EMBO J. 15:5314-5325.[Medline]
40 - Konishi, H., M. Tanaka, Y. Takemura, H. Matsuzaki, Y. Ono, U. Kikkawa, and Y. Nishizuka. 1997. Activation of protein kinase C by tyrosine phosphorylation in response to H2O2. Proc. Natl. Acad. Sci. USA 94:11233-11237.[Abstract/Free Full Text]
41 - Lander, H. M. 1997. An essential role for free radicals and derived species in signal transduction. FASEB J. 11:118-124.[Abstract]
42 - Lemjabbar, H., and C. Basbaum. 2002. Platelet-activating factor receptor and ADAM10 mediate responses to Staphylococcus aureus in epithelial cells. Nat. Med. 8:41-46.[CrossRef][Medline]
43 - Lev, S., H. Moreno, R. Martinez, P. Canoll, E. Peles, J. M. Musacchio, G. D. Plowman, B. Rudy, and J. Schlessinger. 1995. Protein tyrosine kinase PYK2 involved in Ca2+-induced regulation of ion channel and MAP kinase functions. Nature 376:737-745.[CrossRef][Medline]
44 - Levitzki, A., and A. Gazit. 1995. Tyrosine kinase inhibition: an approach to drug development. Science 267:1782-1788.[Abstract/Free Full Text]
45 - Luttrell, L. M., Y. Daaka, and R. J. Lefkowitz. 1999. Regulation of tyrosine kinase cascades by G-protein-coupled receptors. Curr. Opin. Cell Biol. 11:177-183.[CrossRef][Medline]
46 - Luttrell, L. M., R. G. Della, T. van Biesen, D. K. Luttrell, and R. J. Lefkowitz. 1997. Gbetagamma subunits mediate Src-dependent phosphorylation of the epidermal growth factor receptor. A scaffold for G protein-coupled receptor-mediated Ras activation. J. Biol. Chem. 272:4637-4644.[Abstract/Free Full Text]
47 - Madamanchi, N. R., S. Li, C. Patterson, and M. S. Runge. 2001. Thrombin regulates vascular smooth muscle cell growth and heat shock proteins via the JAK-STAT pathway. J. Biol. Chem. 276:18915-18924.[Abstract/Free Full Text]
48 - Ohba, M., K. Ishino, M. Kashiwagi, S. Kawabe, K. Chida, N. Huh, and T. Kuroki. 1998. Induction of differentiation in normal human keratinocytes by adenovirus-mediated introduction of the
and
isoforms of protein kinase C. Mol. Cell. Biol. 18:5199-5207.[Abstract/Free Full Text]
49 - Ohmori, S., Y. Shirai, N. Sakai, M. Fujii, H. Konishi, U. Kikkawa, and N. Saito. 1998. Three distinct mechanisms for translocation and activation of the delta subspecies of protein kinase C. Mol. Cell. Biol. 18:5263-5271.[Abstract/Free Full Text]
50 - Pai, R., B. Soreghan, I. L. Szabo, M. Pavelka, D. Baatar, and A. S. Tarnawski. 2002. Prostaglandin E2 transactivates EGF receptor: a novel mechanism for promoting colon cancer growth and gastrointestinal hypertrophy. Nat. Med. 8:289-293.[CrossRef][Medline]
51 - Pierce, K. L., A. Tohgo, S. Ahn, M. E. Field, L. M. Luttrell, and R. J. Lefkowitz. 2001. Epidermal growth factor (EGF) receptor-dependent ERK activation by G protein-coupled receptors: a co-culture system for identifying intermediates upstream and downstream of heparin-binding EGF shedding. J. Biol. Chem. 276:23155-23160.[Abstract/Free Full Text]
52 - Prenzel, N., E. Zwick, H. Daub, M. Leserer, R. Abraham, C. Wallasch, and A. Ullrich. 1999. EGF receptor transactivation by G-protein-coupled receptors requires metalloproteinase cleavage of proHB-EGF. Nature 402:884-888.[Medline]
53 - Rao, G. N. 1996. Hydrogen peroxide induces complex formation of SHC-Grb2-SOS with receptor tyrosine kinase and activates Ras and extracellular signal-regulated protein kinases group of mitogen-activated protein kinases. Oncogene 13:713-719.[Medline]
54 - Rocic, P., and P. A. Lucchesi. 2001. Down-regulation by antisense oligonucleotides establishes a role for the proline-rich tyrosine kinase PYK2 in angiotensin II-induced signaling in vascular smooth muscle. J. Biol. Chem. 276:21902-21906.[Abstract/Free Full Text]
55 - Sasaki, H., K. Nagura, M. Ishino, H. Tobioka, K. Kotani, and T. Sasaki. 1995. Cloning and characterization of cell adhesion kinase beta, a novel protein-tyrosine kinase of the focal adhesion kinase subfamily. J. Biol. Chem. 270:21206-21219.[Abstract/Free Full Text]
56 - Schieffer, B., M. Luchtefeld, S. Braun, A. Hilfiker, D. Hilfiker-Kleiner, and H. Drexler. 2000. Role of NAD(P)H oxidase in angiotensin II-induced JAK/STAT signaling and cytokine induction. Circ. Res. 87:1195-1201.[Abstract/Free Full Text]
57 - Schindler, C., and J. E. Darnell, Jr. 1995. Transcriptional responses to polypeptide ligands: the JAK-STAT pathway. Annu. Rev. Biochem. 64:621-651.[Medline]
58 - Shichiri, M., M. Yokokura, F. Marumo, and Y. Hirata. 2000. Endothelin-1 inhibits apoptosis of vascular smooth muscle cells induced by nitric oxide and serum deprivation via MAP kinase pathway. Arterioscler. Thromb. Vasc. Biol. 20:989-997.[Abstract/Free Full Text]
59 - Simon, A. R., U. Rai, B. L. Fanburg, and B. H. Cochran. 1998. Activation of the JAK-STAT pathway by reactive oxygen species. Am. J. Physiol. 275:C1640-C1652.
60 - Soltoff, S. P. 2001. Rottlerin is a mitochondrial uncoupler that decreases cellular ATP levels and indirectly blocks protein kinase Cdelta tyrosine phosphorylation. J. Biol. Chem. 276:37986-37992.[Abstract/Free Full Text]
61 - Sun, X., W. Frank, R. Datta, S. Kharbanda, and D. Kufe. 2000. Interaction between protein kinase C delta and the c-Abl tyrosine kinase in the cellular response to oxidative stress. J. Biol. Chem. 275:7470-7473.[Abstract/Free Full Text]
62 - Suzuki, M., G. Raab, M. A. Moses, C. A. Fernandez, and M. Klagsbrun. 1997. Matrix metalloproteinase-3 releases active heparin-binding EGF-like growth factor by cleavage at a specific juxtamembrane site. J. Biol. Chem. 272:31730-31737.[Abstract/Free Full Text]
63 - Tokumaru, S., S. Higashiyama, T. Endo, T. Nakagawa, J. I. Miyagawa, K. Yamamori, Y. Hanakawa, H. Ohmoto, K. Yoshino, Y. Shirakata, Y. Matsuzawa, K. Hashimoto, and N. Taniguchi. 2000. Ectodomain shedding of epidermal growth factor receptor ligands is required for keratinocyte migration in cutaneous wound healing. J. Cell Biol. 151:209-220.[Abstract/Free Full Text]
64 - Touyz, R. M., and E. L. Schiffrin. 1999. Ang II-stimulated superoxide production is mediated via phospholipase D in human vascular smooth muscle cells. Hypertension 34:976-982.[Abstract/Free Full Text]
65 - Umata, T., M. Hirata, T. Takahashi, F. Ryu, S. Shida, Y. Takahashi, M. Tsuneoka, Y. Miura, M. Masuda, Y. Horiguchi, and E. Mekada. 2001. A dual signaling cascade that regulates the ectodomain shedding of heparin-binding epidermal growth factor-like growth factor. J. Biol. Chem. 276:30475-30482.[Abstract/Free Full Text]
66 - Ushio-Fukai, M., K. K. Griendling, P. L. Becker, L. Hilenski, S. Halleran, and R. W. Alexander. 2001. Epidermal growth factor receptor transactivation by angiotensin II requires reactive oxygen species in vascular smooth muscle cells. Arterioscler. Thromb. Vasc. Biol. 21:489-495.[Abstract/Free Full Text]
67 - Wang, D., X. Yu, R. A. Cohen, and P. Brecher. 2000. Distinct effects of N-acetylcysteine and nitric oxide on angiotensin II-induced epidermal growth factor receptor phosphorylation and intracellular Ca2+ levels. J. Biol. Chem. 275:12223-12230.[Abstract/Free Full Text]
68 - Yamamoto, T., H. Matsuzaki, H. Konishi, Y. Ono, and U. Kikkawa. 2000. H2O2-induced tyrosine phosphorylation of protein kinase cdelta by a mechanism independent of inhibition of protein-tyrosine phosphatase in CHO and COS-7 cells. Biochem. Biophys. Res. Commun. 273:960-966.[CrossRef][Medline]
69 - Yu, W. H., J. F. Woessner, Jr., J. D. McNeish, and I. Stamenkovic. 2002. CD44 anchors the assembly of matrilysin/MMP-7 with heparin-binding epidermal growth factor precursor and ErbB4 and regulates female reproductive organ remodeling. Genes Dev. 16:307-323.[Abstract/Free Full Text]
70 - Zhang, Z., P. Oliver, J. J. Lancaster, P. O. Schwarzenberger, M. S. Joshi, J. Cork, and J. K. Kolls. 2001. Reactive oxygen species mediate tumor necrosis factor alpha-converting, enzyme-dependent ectodomain shedding induced by phorbol myristate acetate. FASEB J. 15:303-305.[Free Full Text]
Molecular and Cellular Biology, March 2003, p. 1581-1589, Vol. 23, No. 5
0270-7306/03/$08.00+0 DOI: 10.1128/MCB.23.5.1581-1589.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Nakashima, H., Frank, G. D., Shirai, H., Hinoki, A., Higuchi, S., Ohtsu, H., Eguchi, K., Sanjay, A., Reyland, M. E., Dempsey, P. J., Inagami, T., Eguchi, S.
(2008). Novel Role of Protein Kinase C-{delta} Tyr311 Phosphorylation in Vascular Smooth Muscle Cell Hypertrophy by Angiotensin II. Hypertension
51: 232-238
[Abstract]
[Full Text]
-
Wu, W.-S., Tsai, R. K., Chang, C. H., Wang, S., Wu, J.-R., Chang, Y.-X.
(2006). Reactive Oxygen Species Mediated Sustained Activation of Protein Kinase C {alpha} and Extracellular Signal-Regulated Kinase for Migration of Human Hepatoma Cell Hepg2. Mol Cancer Res
4: 747-758
[Abstract]
[Full Text]
-
Ohtsu, H., Dempsey, P. J., Frank, G. D., Brailoiu, E., Higuchi, S., Suzuki, H., Nakashima, H., Eguchi, K., Eguchi, S.
(2006). ADAM17 Mediates Epidermal Growth Factor Receptor Transactivation and Vascular Smooth Muscle Cell Hypertrophy Induced by Angiotensin II. Arterioscler. Thromb. Vasc. Bio.
26: e133-e137
[Abstract]
[Full Text]
-
Paravicini, T. M., Touyz, R. M.
(2006). Redox signaling in hypertension. Cardiovasc Res
71: 247-258
[Abstract]
[Full Text]
-
Zhao, Y., He, D., Saatian, B., Watkins, T., Spannhake, E. Wm., Pyne, N. J., Natarajan, V.
(2006). Regulation of Lysophosphatidic Acid-induced Epidermal Growth Factor Receptor Transactivation and Interleukin-8 Secretion in Human Bronchial Epithelial Cells by Protein Kinase C{delta}, Lyn Kinase, and Matrix Metalloproteinases. J. Biol. Chem.
281: 19501-19511
[Abstract]
[Full Text]
-
Ohtsu, H., Dempsey, P. J., Eguchi, S.
(2006). ADAMs as mediators of EGF receptor transactivation by G protein-coupled receptors. Am. J. Physiol. Cell Physiol.
291: C1-C10
[Abstract]
[Full Text]
-
Chen, C.-H., Cheng, T.-H., Lin, H., Shih, N.-L., Chen, Y.-L., Chen, Y.-S., Cheng, C.-F., Lian, W.-S., Meng, T.-C., Chiu, W.-T., Chen, J.-J.
(2006). Reactive Oxygen Species Generation Is Involved in Epidermal Growth Factor Receptor Transactivation through the Transient Oxidization of Src Homology 2-Containing Tyrosine Phosphatase in Endothelin-1 Signaling Pathway in Rat Cardiac Fibroblasts. Mol. Pharmacol.
69: 1347-1355
[Abstract]
[Full Text]
-
Armant, D. R., Kilburn, B. A., Petkova, A., Edwin, S. S., Duniec-Dmuchowski, Z. M., Edwards, H. J., Romero, R., Leach, R. E.
(2006). Human trophoblast survival at low oxygen concentrations requires metalloproteinase-mediated shedding of heparin-binding EGF-like growth factor. Development
133: 751-759
[Abstract]
[Full Text]
-
Woolfolk, E. A., Eguchi, S., Ohtsu, H., Nakashima, H., Ueno, H., Gerthoffer, W. T., Motley, E. D.
(2005). Angiotensin II-induced activation of p21-activated kinase 1 requires Ca2+ and protein kinase C{delta} in vascular smooth muscle cells. Am. J. Physiol. Cell Physiol.
289: C1286-C1294
[Abstract]
[Full Text]
-
Alblas, J., Honing, H., Renardel de Lavalette, C., Brown, M. H., Dijkstra, C. D., van den Berg, T. K.
(2005). Signal Regulatory Protein {alpha} Ligation Induces Macrophage Nitric Oxide Production through JAK/STAT- and Phosphatidylinositol 3-Kinase/Rac1/NAPDH Oxidase/H2O2-Dependent Pathways. Mol. Cell. Biol.
25: 7181-7192
[Abstract]
[Full Text]
-
Mifune, M., Ohtsu, H., Suzuki, H., Nakashima, H., Brailoiu, E., Dun, N. J., Frank, G. D., Inagami, T., Higashiyama, S., Thomas, W. G., Eckhart, A. D., Dempsey, P. J., Eguchi, S.
(2005). G Protein Coupling and Second Messenger Generation Are Indispensable for Metalloprotease-dependent, Heparin-binding Epidermal Growth Factor Shedding through Angiotensin II Type-1 Receptor. J. Biol. Chem.
280: 26592-26599
[Abstract]
[Full Text]
-
Zhuang, S., Yan, Y., Han, J., Schnellmann, R. G.
(2005). p38 Kinase-mediated Transactivation of the Epidermal Growth Factor Receptor Is Required for Dedifferentiation of Renal Epithelial Cells after Oxidant Injury. J. Biol. Chem.
280: 21036-21042
[Abstract]
[Full Text]
-
Cai, H.
(2005). NAD(P)H Oxidase-Dependent Self-Propagation of Hydrogen Peroxide and Vascular Disease. Circ. Res.
96: 818-822
[Abstract]
[Full Text]
-
Mifune, M., Ohtsu, H., Suzuki, H., Frank, G. D., Inagami, T., Utsunomiya, H., Dempsey, P. J., Eguchi, S.
(2004). Signal transduction of betacellulin in growth and migration of vascular smooth muscle cells. Am. J. Physiol. Cell Physiol.
287: C807-C813
[Abstract]
[Full Text]
-
Sandberg, E. M., Sayeski, P. P.
(2004). Jak2 Tyrosine Kinase Mediates Oxidative Stress-induced Apoptosis in Vascular Smooth Muscle Cells. J. Biol. Chem.
279: 34547-34552
[Abstract]
[Full Text]
-
Konishi, A., Aizawa, T., Mohan, A., Korshunov, V. A., Berk, B. C.
(2004). Hydrogen Peroxide Activates the Gas6-Axl Pathway in Vascular Smooth Muscle Cells. J. Biol. Chem.
279: 28766-28770
[Abstract]
[Full Text]
-
Upadhyay, D., Bundesmann, M., Panduri, V., Correa-Meyer, E., Kamp, D. W.
(2004). Fibroblast Growth Factor-10 Attenuates H2O2-Induced Alveolar Epithelial Cell DNA Damage: Role of MAPK Activation and DNA Repair. Am. J. Respir. Cell Mol. Bio.
31: 107-113
[Abstract]
[Full Text]
-
Fischer, O. M., Hart, S., Gschwind, A., Prenzel, N., Ullrich, A.
(2004). Oxidative and Osmotic Stress Signaling in Tumor Cells Is Mediated by ADAM Proteases and Heparin-Binding Epidermal Growth Factor. Mol. Cell. Biol.
24: 5172-5183
[Abstract]
[Full Text]
-
Zhougang, S., Schnellmann, R. G.
(2004). H2O2-induced transactivation of EGF receptor requires Src and mediates ERK1/2, but not Akt, activation in renal cells. Am. J. Physiol. Renal Physiol.
286: F858-F865
[Abstract]
[Full Text]
-
Shah, B. H., Farshori, M. P., Catt, K. J.
(2004). Neuropeptide-induced Transactivation of a Neuronal Epidermal Growth Factor Receptor Is Mediated by Metalloprotease-dependent Formation of Heparin-binding Epidermal Growth Factor. J. Biol. Chem.
279: 414-420
[Abstract]
[Full Text]
-
Ichiki, T., Tokunou, T., Fukuyama, K., Iino, N., Masuda, S., Takeshita, A.
(2003). Cyclic AMP Response Element-Binding Protein Mediates Reactive Oxygen Species-Induced c-fos Expression. Hypertension
42: 177-183
[Abstract]
[Full Text]