Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.10.1 (ERK)
95,504 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Kringle-1 structure of plasminogen (PGK-1), the Kringle-2 structure of tissue plasminogen activator (PAK-2) and the Kringle structure of prourokinase (UKK) has been modeled on the basis of the three-dimensional structure of Kringle-1 of prothrombin (PTK-1) at 2.8 A resolution. The predicted three-dimensional structure of these Kringles shows that the binding site of PGK-1 is characterized by an apparent dipolar site, the polar parts of which are separated by a hydrophobic region. PAK-2 possesses the anionic center but has not a cationic binding center which might be provided by a guanidinium group from Arg-69 located adjacent to the Arg-71 position. UKK possesses neither the anionic binding center nor the cationic center which are probably the main reason for the poor fibrin specificity of urokinase.
...
PMID:The structural basis of the poor fibrin specificity of urokinase(I)--knowledge-based prediction of kringle structures of urokinase and its related proteins. 158 Oct 2

A transcriptional silencer has been identified in the 5' regulatory region of the human urokinase plasminogen activator (uPA) gene. This region is able to block transcription from the human u-PA as well as the rabbit beta-globin promoters in a cell type specific and orientation independent way. The silencer is enhancer dependent and is active in two cell lines (HeLa and CV-1) which produce little if any uPA, but not in the high uPA producer PC3. Silencing activity and enhancer dependence can be separated: the silencing activity has been localized to the DNA fragment -660 to -536, while the enhancer dependence is located in the -536 to -308 fragment. The DNA sequence of the silencer region contains an element that closely resembles the TGF-beta responsive negative element TIE.
...
PMID:A cell-type specific and enhancer-dependent silencer in the regulation of the expression of the human urokinase plasminogen activator gene. 171 Mar 52

The parent R3230 AC rat mammary carcinoma cell line and the two variant cell lines, R3230 AC MET and R3230 AC LR, differ with respect to their abilities to invade bony matrices and to form lung colonies (experimental metastases). Both the R3230 AC and the R3230 AC MET, a cell line selected in vivo for enhanced metastatic capability, express high potentials for invasiveness and lung colony formation, while the Con A- and WGA-resistant R3230 AC LR cell line grows expansively at the periosseus implantation site and is unable to form lung colonies after intravenous inoculation. The abilities to invade bone and to metastasize to the lung are well correlated with the fibrinolytic activity and the production of urokinase-type plasminogen activators. The contribution of plasminogen activators to invasiveness and metastasis has been ascribed to its role in the fibrinolytic and collagenolytic (i.e., activation of latent collagenase) cascades.
...
PMID:Correlation of fibrinolytic activity with invasion and metastasis of R3230 AC rat mammary carcinoma cell lines. 359 83

The HER2/neu (c-erbB2) protooncogene, which encodes a transmembrane receptor (p185neu), contributes to tumor cell invasion/metastasis through mechanism(s) which are, at present, poorly defined. Since basement membrane degradation is a prerequisite for tumor progression, we undertook a study to determine if the expression of urokinase, a key protease implicated in extracellular matrix proteolysis, was regulated by this oncogene. Stable overexpression of a cDNA encoding HER2/neu in H460 lung cancer cells led to elevated secretion of urokinase which was a consequence of a higher level of protease mRNA. Transfection of the HER2/neu-overexpressing B 104-1 cells with a CAT reporter construct driven by the urokinase promoter, gave rise to increased CAT activity when compared with parental NIH3T3 cells, which have low levels of HER2/neu, suggesting that the protooncogene can enhance urokinase promoter activity. Since the enhanced expression of HER2/neu results in increased tumor invasion/metastasis (1), these data suggest that, at least in vitro, HER2/neu-induced expression of urokinase may contribute to tumor progression in p185neu-positive cancers.
...
PMID:Up-regulation of urokinase-type plasminogen activator expression by the HER2/neu proto-oncogene. 765 95

Hepatocyte growth factor/scatter factor (HGF/SF) is a heparin-binding polypeptide which shares structural domains with enzymes of the blood clotting cascade. HGF/SF is secreted by cells of mesodermal origin and has powerful mitogenic, motogenic and morphogenic activity on epithelial and endothelial cells. HGF/SF is produced as a biologically inactive single-chain precursor (pro-HGF/SF) most of which is sequestered on the cell surface or bound to the extracellular matrix. Maturation into the active alpha beta heterodimer results from proteolytic cleavage by a urokinase-type protease, which acts as a pro-HGF/SF convertase. The primary determinant for receptor binding appears to be located within the alpha-chain. The interaction of the alpha-chain with the receptor is sufficient for the activation of the signal cascade involved in the motility response. However, the complete HGF/SF protein seems to be required to elicit a mitogenic response. HGF/SF binds with high affinity to a transmembrane receptor, p190MET, encoded by the MET proto-oncogene. p190MET is the prototype of a distinct subfamily of heterodimeric tyrosine kinases, including the putative receptors Ron and Sea. The mature form of p190MET is a heterodimer of two disulfide-linked subunits (alpha and beta). The alpha-subunit is extracellular and heavily glycosylated. The beta-subunit consists of an extracellular portion involved in ligand binding, a membrane spanning segment, and a cytoplasmic tyrosine kinase domain. Both subunits derive from glycosylation and proteolytic cleavage of a common precursor of 170 kDa. In polarized epithelial cells the HGF/SF receptor is selectively exposed in the basolateral plasmalemma, where it is associated with detergent-insoluble components. Two Met isoforms, carrying an intact ligand binding domain but lacking the kinase domain due to truncation of the beta-subunit, arise from alternative post-transcriptional processing of the mature form. One truncated form is soluble and released from the cells. HGF/SF binding triggers tyrosine autophosphorylation of the receptor beta-subunit. Autophosphorylation on the major phosphorylation site Y1235 upregulates the kinase activity of the receptor, increasing the Vmax of the phosphotransfer reaction. Negative regulation of the kinase activity occurs through phosphorylation of a unique serine residue (S985) located in the juxtamembrane domain of the receptor. This phosphorylation is triggered by two distinct pathways involving either protein kinase C activation or increase in intracellular Ca2+ concentration. Upon ligand binding, the HGF/SF receptor recruits and activates several cytoplasmic effectors, including phosphatidylinositol 3-kinase (PI 3-K), phospholipase C-gamma (PLC-gamma), pp60c-Src, a tyrosine phosphatase, and a Ras-guanine nucleotide exchanger.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Identification of functional domains in the hepatocyte growth factor and its receptor by molecular engineering. 776 52

HGF is secreted by mesenchymal cells and regulates motogenesis, mitogenesis, and morphogenesis of epithelial and endothelial cells. HGF is a heterodimer of two glycosylated chains, alpha and beta, bound together by a disulfide bond. The molecule is synthesized as single chain precursor devoid of biological activity (pro-HGF). The critical step in pro-HGF activation is a proteolytic cleavage generating the two chain form. This step occurs in the extracellular environment, and is catalyzed by urokinase. Two alternative transcripts originate two HGF variants. One bears a deletion of five amino acids in the alpha chain, and has the same properties of the full-size protein. The other one contains only the first portion of the alpha chain (two kringle HGF). Two kringle HGF binds the HGF receptor, triggers its tyrosine kinase activity and behaves as a partial agonist, inducing motogenesis but not mitogenesis in target cells. The HGF receptor is the tyrosine kinase encoded by the c-MET pro-oncogene, a tyrosine kinase receptor. This molecule is an heterodimer of an extracellular alpha chain disulfide linked to a transmembrane beta chain. The cytoplasmic portion of the beta chain contains the catalytic domain and critical sites for the regulation of its kinase activity. In the C-terminal tail, a bidentate motif containing two tyrosines associates the transducers responsible for HGF signalling.
...
PMID:Hepatocyte growth factor and its receptor, the tyrosine kinase encoded by the c-MET proto-oncogene. 798 17

For the integration of new cell biological prognostic factors in daily clinical practice, we need to know not only their prognostic power with respect to prediction of relapse free and overall survival, but also their possible relation to response to endocrine therapy or chemotherapy in order to select adequate treatment for each patient. A large number of cell biological parameters are currently available to predict the prognosis of patients with breast cancer, but it is still difficult to predict the response to treatment accurately. A valuable prognostic factor can be a worthless predictive factor for endocrine therapy or chemotherapy, and vice versa. High tumour levels of ER, PGR, AR and PS2 protein predict a relatively good response to endocrine therapy, whereas EGFR positivity, HER2/neu positivity, aneuploidy, high proliferation indices and possibly high u-PA levels indicate a good chance of a poor response to endocrine therapy in metastatic breast cancer. With respect to chemotherapy, a high proliferation rate and HER2/neu amplification predict a good response to therapy in metastatic disease, whereas MDR gene expression and possibly c-myc amplification are related to a worse response. In conclusion, the newer cell biological parameters can be used to select high and low risk patients and type of systemic treatment and can be used as targets for new treatment modalities.
...
PMID:Prognostic factors and response to therapy in breast cancer. 801 96

A large number of cell biological parameters are currently available to predict the prognosis of patients with breast cancer, but it is still difficulty accurately to predict the response to treatment. A valuable prognostic factor can be a poor predictive factor for response, and vice versa. High tumor levels of ER, PgR, AR and pS2 predict a relatively good response to endocrine therapy, while EGF-R positively, HER2/neu positivity, aneuploidy, high proliferation indices and possibly high uPA levels indicate a high chance of poor response to endocrine therapy in metastatic breast cancer. With respect to chemotherapy, a high proliferation rate and HER2/neu amplification predict a good response to therapy in metastatic disease, while MDR gene expression and possibly c-myc amplification are related to a worse response. In conclusion, the newer cell biological parameters can be used to select high and low-risk patients, type of systemic treatment, and as targets for new treatment modalities.
...
PMID:Cell biological factors associated with the response of breast cancer to systemic treatment. 848 34

Kaposi's sarcoma is a highly vascularized multifocal tumor which frequently appears as a complication of HIV infection. It has been suggested that a disorder in the cytokine network may contribute to the development of the disease. We examined the expression of several cytokines in human sporadic Kaposi's-sarcoma specimens, as well as in spindle cells cultured from human lesions, and consistently found high levels of expression of hepatocyte growth factor (HGF). In addition, human lesion-derived spindle cells synthesize and secrete biologically active hepatocyte growth factor and express the hepatocyte-growth-factor receptor (c-MET). Moreover, elevated levels of transforming growth factor beta 1 (TGF beta 1) mRNA were found in lesions of human sporadic Kaposi's sarcoma and in lesion-derived spindle cells which also over-express urokinase. Since HGF, TGF beta 1 and urokinase are all involved in capillary-vessel organization, dysregulation of these interacting agents may play a role in the initiation and/or progression of Kaposi's sarcoma, stimulating the growth of spindle cells and recruiting endothelial cells into the lesion.
...
PMID:Over-expression of hepatocyte growth factor in human Kaposi's sarcoma. 856 12

Expression of polyomavirus middle-T antigen (middle-T) is involved in the formation of various tumors in vivo, e.g. hemangiomas and mammary gland tumors. Several genes have been shown to be activated in middle-T-expressing cells, but the underlying mechanisms have only been partially elucidated. Among the genes regulated by middle-T, the urokinase-type plasminogen activator (uPA) gene seems to be of primary importance for the development of the transformed phenotype. We have found that the uPA gene is highly expressed in eEnd2 cells derived from a hemangioma expressing middle-T. NIH3T3 cells show negligible levels of uPA mRNA but its expression was highly induced by infecting with a middle-T-expressing retrovirus. Middle-T did not affect uPA mRNA stability. Transient cotransfection experiments using a uPA-receptor gene construct and a middle-T expression vector showed that high uPA mRNA levels are due to increased uPA promoter activity. Analyses of various signaling molecules by transient cotransfection assays and in vitro kinase assays established that a signaling pathway involving c-Src, SOS, Ras, Raf-1 and ERK is activated by middle-T in NIH3T3 cells, resulting in the activation of the uPA gene promoter via PEA3/AP1 elements. In contrast, in eEND2 cells uPA gene induction is only partially dependent on this pathway, suggesting the involvement of additional signaling molecules in endothelial cells.
...
PMID:Urokinase-type plasminogen activator gene regulation by polyomavirus middle-T antigen. 857 Jan 90


1 2 3 4 5 6 7 8 9 10 Next >>