Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.7.10.1 (
ERK
)
95,504
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The granulin-epithelin precursor, progranulin, PC-cell-derived growth factor or acrogranin, is a high molecular weight secreted mitogen. It is abundantly expressed in rapidly cycling epithelial cells, in the immune system and in neurons, such as cerebellar Purkinje cells. Progranulin contributes to tumorigenesis in diverse cancers, including breast cancer, clear cell renal carcinoma, invasive ovarian carcinoma and glioblastoma. It regulates the rate of epithelial cell division in responsive epithelial cells, and confers an invasive phenotype on these cells. It is involved in the wound response. During embryogenesis, progranulin accelerates blastocyst formation, and is a growth factor for trophectodermal cells. In the neonate, progranulin, regulates the hormone-dependent virilization of the hypothalamus. It activates phosphorylation of Shc, and p44/42 MAPK (mitogen activated protein kinase) in the
ERK
(extracellular regulated kinase) signaling pathway; PI3K (phosophatidyl inositol-3-kinase),
AKT
/protein kinase B, and p70S6kinase in the phosophatidyl inositol-3-kinase pathway; and focal adhesion kinase in the adhesion/motility pathway. The signaling properties of progranulin are apparently similar to those of classic growth factors, but the functional properties of progranulin distinguish it from these molecules. Deleting the insulin-like growth factor I receptor from murine embryonic fibroblasts blocks proliferation in response to all classic growth factors, such as epidermal growth factor, or platelet-derived growth factor, whereas progranulin retains mitotic activity on these cells. The defined biological actions of progranulin probably represent a small fraction of its overall functions. Transcriptome analyses show that the progranulin gene is induced in numerous situations that vary from obesity to the transcriptional response of cells to antineoplastic drugs. Here, the biological roles of progranulin will be reviewed, with an emphasis on cancer and cell proliferation.
...
PMID:Progranulin (granulin-epithelin precursor, PC-cell derived growth factor, acrogranin) in proliferation and tumorigenesis. 1297 94
The Met receptor tyrosine kinase has been shown to be overexpressed or mutated in a variety of solid tumors and has, therefore, been identified as a good candidate for molecularly targeted therapy. Activation of the Met tyrosine kinase by the TPR gene was originally described in vitro through carcinogen-induced rearrangement. The TPR-
MET
fusion protein contains constitutively elevated Met tyrosine kinase activity and constitutes an ideal model to study the transforming activity of the Met kinase. We found, when introduced into an interleukin 3-dependent cell line, TPR-
MET
induces factor independence and constitutive tyrosine phosphorylation of several cellular proteins. One major tyrosine phosphorylated protein was identified as the TPR-
MET
oncoprotein itself. Inhibition of the Met kinase activity by the novel small molecule drug SU11274 [(3Z)-N-(3-chlorophenyl)-3-([3,5-dimethyl-4-[(4-methylpiperazin-1-yl)carbonyl]-1H-pyrrol-2-yl]methylene)-N-methyl-2-oxo-2,3-dihydro-1H-indole-5-sulfonamide] led to time- and dose-dependent reduced cell growth. The inhibitor did not affect other tyrosine kinase oncoproteins, including BCR-ABL, TEL-JAK2, TEL-PDGFbetaR, or TEL-ABL. The Met inhibitor induced G(1) cell cycle arrest and apoptosis with increased Annexin V staining and caspase 3 activity. The autophosphorylation of the Met kinase was reduced on sites that have been shown previously to be important for activation of pathways involved in cell growth and survival, especially the phosphatidylinositol-3'-kinase and the Ras pathway. In particular, we found that the inhibitor blocked phosphorylation of
AKT
, GSK-3beta, and the pro-apoptotic transcription factor FKHR. The characterization of SU11274 as an effective inhibitor of Met tyrosine kinase activity illustrates the potential of targeting for Met therapeutic use in cancers associated with activated forms of this kinase.
...
PMID:A novel small molecule met inhibitor induces apoptosis in cells transformed by the oncogenic TPR-MET tyrosine kinase. 1450 Mar 82
Insulin-like growth factor-1 (IGF-I) is a growth and survival factor in human multiple myeloma (MM) cells. Here we examine the effect of IGF-I on MM cell adhesion and migration, and define the role of beta1 integrin in these processes. IGF-I increases adhesion of MM.1S and OPM6 MM cells to fibronectin (FN) in a time- and dose-dependent manner, as a consequence of IGF-IR activation. Conversely, blocking anti-beta1 integrin monoclonal antibody, RGD peptide, and cytochalasin D inhibit IGF-I-induced cell adhesion to FN. IGF-I rapidly and transiently induces association of IGF-IR and beta1 integrin, with phosphorylation of IGF-IR, IRS-1, and p85(PI3-K). IGF-I also triggers phosphorylation of
AKT
and
ERK
significantly. Both IGF-IR and beta1 integrin colocalize to lipid rafts on the plasma membrane after IGF-I stimulation. In addition, IGF-I triggers polymerization of F-actin, induces phosphorylation of p125(FAK) and paxillin, and enhances beta1 integrin interaction with these focal adhesion proteins. Importantly, using pharmacological inhibitors of phosphatidylinositol 3'-kinase (PI3-K) (LY294002 and wortmannin) and extracellular signal-regulated kinase (PD98059), we demonstrate that IGF-I-induced MM cell adhesion to FN is achieved only when PI3-K/
AKT
is activated. IGF-I induces a 1.7-2.2 (MM.1S) and 2-2.5-fold (OPM6) increase in migration, whereas blocking anti-IGF-I and anti-beta1 integrin monoclonal antibodies, PI3-K inhibitors, as well as cytochalasin D abrogate IGF-I-induced MM cell transmigration. Finally, IGF-I induces adhesion of CD138+ patient MM cells. Therefore, these studies suggest a role for IGF-I in trafficking and localization of MM cells in the bone marrow microenvironment. Moreover, they define the functional association of IGF-IR and beta1 integrin in mediating MM cell homing, providing the preclinical rationale for novel treatment strategies targeting IGF-I/IGF-IR in MM.
...
PMID:Insulin-like growth factor-1 induces adhesion and migration in human multiple myeloma cells via activation of beta1-integrin and phosphatidylinositol 3'-kinase/AKT signaling. 1452 9
HSP90 inhibitors such as 17AAG have the major therapeutic advantage that they exert downstream inhibitory effects on multiple oncogenic client proteins. They therefore block several mission critical cancer-causing pathways and have the potential to modulate all of the hallmark biological features of malignancy. Consistent with this combinatorial anti-oncogenic profile, 17AAG exhibits broad-spectrum antitumour activity against cultured cancer cell lines and in vivo animal models. However, there are clear differences in sensitivity between various cancer cell lines and it is quite possible that some tumour types or individual patients will be more responsive in the clinic than others. We describe the methods used to investigate the genes and proteins involved in the mechanism of action of HSP90 inhibitors and discuss the significance of these for cellular sensitivity. Methods used involve the conventional cell and molecular biology techniques, together with the more recent application of high throughput global technologies such as gene expression microarrays and proteomics. Selected examples that seem to play a role in sensitivity to HSP90 inhibitors are highlighted and the potential relevance to the response of cancer patients is discussed. Important determinants of response include: 1) Dependence upon key HSP90 client proteins such as
ERBB2
, steroid hormone receptors and
AKT
/PKB; 2) Levels of HSP90 family members and co-chaperones, such as HSP70 and AHA1; and 3) expression of various cell cycle and apoptotic regulators. In the case of 17AAG, metabolic enzymes such as NQO1 and membrane efflux pumps are also important for sensitivity.
...
PMID:Genes and proteins governing the cellular sensitivity to HSP90 inhibitors: a mechanistic perspective. 1452 85
Mutations in the proto-oncogene c-kit cause constitutive kinase activity of its product, KIT protein, and are associated with human mastocytosis and gastrointestinal stromal tumors (GISTs). Although currently available tyrosine kinase inhibitors are effective in the treatment of GISTs, there has been limited success in the treatment of mastocytosis. 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a benzoquinoid ansamycin antibiotic, which binds to heat shock protein 90 (hsp90) causes destabilization of various hsp90-dependent kinases important in oncogenesis. Treatment with 17-AAG of the mast cell line HMC-1.2, harboring the Asp816Val and Val560Gly
KIT
mutations, and the cell line HMC-1.1, harboring a single Val560Gly mutation, causes both the level and activity of
KIT
and downstream signaling molecules
AKT
and STAT3 to be down-regulated following drug exposure. These data were validated using Cos-7 cells transfected with wild-type and mutated
KIT
. 17-AAG promotes cell death of both HMC mast cell lines. In addition, neoplastic mast cells isolated from patients with mastocytosis, incubated with 17-AAG ex vivo, are selectively sensitive to the drug compared to the mononuclear fraction. These data provide compelling evidence that 17-AAG may be effective in the treatment of c-kit-related diseases including mastocytosis, GISTs, mast cell leukemia, subtypes of acute myelogenous leukemia, and testicular cancer.
...
PMID:17-Allylamino-17-demethoxygeldanamycin (17-AAG) is effective in down-regulating mutated, constitutively activated KIT protein in human mast cells. 1455 Nov 38
Expression of survival p-
AKT
and p-
ERK
signals was examined by immunohistochemistry and Western blotting in the lumbar spinal cord of 12-week-old presymptomatic mice with human mutant G93A SOD1 gene (transgenic, Tg) and their wild-type (Wt) littermates during normoxia, and 0 and 6 h after 2 h of 9% hypoxia. During normoxia, a stronger p-
AKT
signal was detected in the nucleus of the motor neurons of Tg animals. At 0 h of recovery from 2 h of hypoxia, both p-
AKT
and p-
ERK
signals were induced at a slightly lower level in Tg (1.1-1.2-fold) compared to those of Wt (1.2-1.5-fold) animals. At 6 h of recovery, both p-
AKT
and p-
ERK
signals were sustained in the lumbar spinal motor neurons of Tg animals, while those in Wt animals quickly returned to baseline level. As a control, at 6 h of recovery, the hippocampus of Tg animals showed significantly sustained p-
AKT
levels, but not p-
ERK
levels, compared to Wt. The current results suggest that the presence of mutant SOD1 alters survival p-
AKT
and p-
ERK
signals, possibly to compensate for the acquired gain-of-function of the mutant protein.
...
PMID:Sustained induction of survival p-AKT and p-ERK signals after transient hypoxia in mice spinal cord with G93A mutant human SOD1 protein. 1456 29
Accumulating evidence indicates that expression of
anaplastic lymphoma kinase
(
ALK
), typically due to t(2;5) translocation that creates an NPM-
ALK
fusion gene, defines a distinct type of T/null-cell lymphoma (TCL) within a vastly heterogeneous group of anaplastic large cell lymphomas. Through the translocation mechanism or as a full-length apparently intact protein,
ALK
also is expressed by a subset of inflammatory myofibroblastic tumors, glioblastomas, diffuse large B-cell lymphomas, and other malignant neoplasms. Owing to the recent progress in understanding its pathogenesis, ALK+ TCL has become a model malignant neoplasm in which morphology-based diagnosis and classification are gradually shifting toward biology-based diagnosis. Several lines of experimental evidence indicate that the ectopically expressed
ALK
is oncogenic in ALK+ TCL by being constitutively active owing to autophosphorylation and, consequently, by stimulating several critical signal transduction pathways involving phospholipase C-gamma,
AKT
, and STAT3 (signal transducer and activator of transcription 3). Targeting
ALK
and, perhaps, its downstream signaling effector proteins represents a promising novel therapeutic approach to ALK+ TCL. Diagnostic implications of the
ALK
expression in ALK+ TCL and other malignant neoplasms and the related current controversies are discussed.
...
PMID:Expression of anaplastic lymphoma kinase in non-Hodgkin's lymphomas and other malignant neoplasms. Biological, diagnostic, and clinical implications. 1456 15
The role of lysophosphatidylcholine (LPC) in the induction of MCP-1, IL-8 and RANTES, which are chemotactic factors to monocytes, neutrophils and lymphocytes, respectively, by human vascular endothelial cells (EC), was examined. LPC induced the expression of MCP-1 and IL-8 in a concentration- and time-dependent manner in microvascular EC (MVEC) and in large vessel EC from aorta, pulmonary artery and umbilical vein. LPC also induced RANTES in MVEC but not in large vessel EC. Signaling pathways responsible for LPC induction of chemokines were examined in MVEC. LPC and TNFalpha, a cytokine secreted in sites of inflammation, additively stimulated RANTES expression. LPC did not augment TNFalpha induction of MCP-1 or IL-8. A platelet-activating factor receptor antagonist (BN52021) failed to block LPC induction of MVEC chemokines, but the G(i)-protein inhibitor pertussis toxin partially blocked LPC induction of RANTES and IL-8. LPC activated multiple kinases in MVEC; it increased the phosphorylation of ERK1/2,
AKT
and p38 MAP kinase in a time-dependent manner. An inhibitor of the MAPK/
ERK
pathway, PD98059, blocked the phosphorylation of ERK1/2 and RANTES induction by LPC, but augmented IL-8 induction. LY294002, a specific inhibitor of phosphoinositide 3 kinase (PI3 kinase), blunted the phosphorylation of
AKT
and inhibited LPC induction of RANTES more strongly than IL-8. Inhibition of p38 MAP kinase pathway by SB202190 also blocked LPC-induced expression of IL-8 and RANTES. Our results suggest that LPC induction of chemokines in MVEC is distinct from that in large vessel EC, and required the activities of MAP kinases and PI3 kinase for the induction of RANTES and IL-8. We speculate that the presence of LPC, a bioactive lipid product of phospholipase A(2) (PLA(2)) and a constituent of oxidized low-density lipoprotein, can differentially influence the chemotaxis of particular leukocyte subpopulations during inflammation.
...
PMID:Lysophosphatidylcholine regulates human microvascular endothelial cell expression of chemokines. 1459 94
Apigenin is a low toxicity and non-mutagenic phytopolyphenol and protein kinase inhibitor. It exhibits anti-proliferating effects on human breast cancer cells. Here we examined several human breast cancer cell lines having different levels of
HER2
/neu expression and found that apigenin exhibited potent growth-inhibitory activity in
HER2
/neu-overexpressing breast cancer cells but was much less effective for those cells expressing basal levels of
HER2
/neu. Induction of apoptosis was also observed in
HER2
/neu-overexpressing breast cancer cells in a dose- and time-dependent manner. However, the one or more molecular mechanisms of apigenin-induced apoptosis in
HER2
/neu-overexpressing breast cancer cells remained to be elucidated. A cell survival pathway involving phosphatidylinositol 3-kinase (PI3K), and Akt is known to play an important role in inhibiting apoptosis in response to
HER2
/neu-overexpressing breast cancer cells, which prompted us to investigate whether this pathway plays a role in apigenin-induced apoptosis in
HER2
/neu-overexpressing breast cancer cells. Our results showed that apigenin inhibits Akt function in tumor cells in a complex manner. First, apigenin directly inhibited the PI3K activity while indirectly inhibiting the Akt kinase activity. Second, inhibition of
HER2
/neu autophosphorylation and transphosphorylation resulting from depleting
HER2
/neu protein in vivo was also observed. In addition, apigenin inhibited Akt kinase activity by preventing the docking of PI3K to
HER2
/
HER3
heterodimers. Therefore, we proposed that apigenin-induced cellular effects result from loss of
HER2
/neu and
HER3
expression with subsequent inactivation of PI3K and
AKT
in cells that are dependent on this pathway for cell proliferation and inhibition of apoptosis. This implies that the inhibition of the
HER2
/
HER3
heterodimer function provided an especially effective strategy for blocking the
HER2
/neu-mediated transformation of breast cancer cells. Our results also demonstrated that apigenin dissociated the complex of
HER2
/neu and GRP94 that preceded the depletion of
HER2
/neu. Apigenin-induced degradation of mature
HER2
/neu involves polyubiquitination of
HER2
/neu and subsequent hydrolysis by the proteasome.
...
PMID:Apigenin induces apoptosis through proteasomal degradation of HER2/neu in HER2/neu-overexpressing breast cancer cells via the phosphatidylinositol 3-kinase/Akt-dependent pathway. 1460 23
Epidermal growth factor (EGF) receptor (
EGFR
) is commonly amplified and/or mutated in high-grade gliomas. Abnormal signaling from this receptor tyrosine kinase is believed to contribute to the malignant phenotypes seen in these tumors. Highly specific small molecule inhibitors of this receptor tyrosine kinase have been developed and may potentially improve the treatment of these highly aggressive brain tumors. A glioma cell line overexpressing
EGFR
was developed to mimic the situation of a malignant glioma with amplified
EGFR
, and this line was used to characterize the response to specific
EGFR
inhibitors. Treatment of our in vitro glioma model with the
EGFR
kinase inhibitors ZD1839 (Iressa) or PD153035, synthetic anilinoquinazolines with high specificity for
EGFR
, resulted in significant suppression of
EGFR
autophosphorylation even with very low levels of drug. However, significantly higher levels of drug were required to fully inhibit signaling through the phosphatidylinositol 3'-kinase/
AKT
and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (ERK) pathways. Interestingly, not all downstream signaling pathways displayed this resistance to inhibition. EGF-dependent activation of signal transducers and activators of transcription-3 occurred at low doses of
EGFR
inhibitors. The uncoupling of
EGFR
autophosphorylation and signaling through
AKT
and ERK was not dependent on
EGFR
overexpression. In addition, although this response was seen in other glioma and the SK-BR3 breast cancer cell lines, it was not universally present. The SQ20B head and neck squamous carcinoma cell line demonstrated loss of EGF-dependent
AKT
and ERK activation even at low doses of inhibitor. Despite significant loss of EGF-dependent autophosphorylation, the inability of low levels of
EGFR
inhibitor to suppress some downstream signaling pathways in our model glioma cell line permitted continued EGF-responsive decreases in the expression of the cyclin-dependent kinase inhibitor p27KIP and EGF-dependent proliferation/cell cycle progression. Although the mechanism responsible for the differential sensitivity of the various signal transduction pathways to
EGFR
inhibitors remains unclear, signaling through erbB2 does not appear to be involved. The ability of certain tumor cells to maintain signaling through
AKT
and ERK under
EGFR
inhibition may represent a potential mechanism of resistance by which a tumor cell may escape the antiproliferative activity of this new class of drugs.
...
PMID:Resistance to small molecule inhibitors of epidermal growth factor receptor in malignant gliomas. 1461 44
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>