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 respective role of central vs. peripheral CCK-B receptors in the recently reported anxiolytic effects of CCK-B antagonists remains to be firmly established. We therefore investigated the in vivo binding properties of cerebral CCK receptors after i.c.v. injection into mice of [3H]pBC 264 ([3H]propionyl-Tyr(SO3H)-gNle-mGly- Trp-(NMe)Nle-Asp-Phe-NH2), a highly potent, peptidase-resistant and selective CCK-B agonist. The specific binding of [3H]pBC 264 was reversible and saturable. The dose producing 50% receptor occupancy was 25 pmol and the Bmax was 0.9 pmol/brain 15 min after injection. I.c.v. administered CCK8 (ID50 8500 pmol) was 200-fold less potent than pBC 264 (ID50 43 pmol) in inhibiting specific [3H]pBC 264 binding; CCK8NS, CCK5 and
CCK4
being slightly less potent than CCK8. Aminopeptidases play a major role in degrading CCK8 since the protected analog pCCK8 or CCK8 in the presence of an aminopeptidase inhibitor exhibited higher affinities than CCK8. I.v. administration of pBC 264 (20 mg/kg) inhibited [3H]pBC 264 specific binding by about 72%, confirming its ability to enter the brain. In contrast,
CCK4
was unable to modify [3H]pBC 264 binding. As expected, the CCK-A antagonist (L364,718) did not inhibit [3H]pBC 264 binding, while at the highest dose used (40 mg/kg i.p.) the CCK-B antagonist (L365,260) inhibited binding by 20%. Several hypotheses are discussed to account for the very low i.v. doses of
CCK4
and L365,260 needed to produce anxiogenic and anxiolytic responses, respectively.
Eur J Pharmacol 1991
Dec
17
PMID:In vivo binding affinities of cholecystokinin agonists and antagonists determined using the selective CCKB agonist [3H]pBC 264. 179 61
Roll-over test (ROT) was performed on 128 selected nulliparous women between 28 and 32 weeks of gestation. Considering the high frequency of true-positive (81.5%) and true-negative results (88.1%), ROT seems to show, in clinical practice, a good sensitivity (64.7%) and an excellent specificity (94.7%). The and an excellent specificity (94.7%). The results of this study confirm that ROT is a true predictor of pregnant women at risk for future development of
EPH
gestosis.
Minerva Ginecol 1991
Dec
PMID:[Prediction of EPH gestosis by means of the roll-over test. Clinical contribution]. 181 70
Age-related changes manifested in MHC-linked recognition of bone marrow (BM) cells by the thymic stroma were studied in vitro model of thymus-BM chimeras. Fetal thymuses (FT) depleted of self-lymphocytes were colonized with BM cells from syngeneic and allogeneic donor mice. When cells from young (3-month-old) or old (24-month-old) donors syngeneic to the stroma were seeded in a mixture with cells of allogeneic young origins (C57BL/6J-Thy1.2 and
ARK
/J-Thy1.1 seeded onto C57BL/6J FT), the syngeneic cells showed an age-related developmental advantage. Accordingly, cells from the old syngeneic mice manifested a significantly reduced capacity to compete with allogeneic cells when compared with the young syngeneic cells. When allogeneic BM cells from young or old mice were seeded onto the thymic stroma in a mixture with BM cells from young donors syngeneic to that stroma (BALB/c-Thy1.2 mixed with C57BL/Ka-Thy1.1 seeded onto C57BL/6J or C57BL/Ka FT), the Thy1+ cells which developed were mainly of syngeneic origin. The age of the allogeneic cells had no significant effect on the results. However, when old allogeneic cells were mixed with old syngeneic cells, the developmental advantage of the syngeneic cells was not manifested. When seeding of allogeneic cells was followed 1 day later by seeding of syngeneic cells, the syngeneic advantage was eliminated, suggesting that the MHC-linked competition began during the first 24 hr of contact with the thymic tissue. When BM-derived thmocytes grown in FT explants were transferred onto second FT recipient explants of the same genotype as the first ones, the syngeneic advantage was abolished, suggesting either that the thymic microenvironment was modified as a result of colonization or that it induced a change in the BM cells. In this respect, the young allogeneic BM-derived thymocytes showed a significant advantage when compared with the old cells. Thus, the MHC-linked syngeneic preference in the early development of BM cells is also manifested in aging mice, yet at a level that is significantly reduced compared with that seen in the young mice.
Cell Immunol 1991
Dec
PMID:Interactions of bone marrow cells from young and old mice with syngeneic and allogeneic thymic tissue. 193 73
We have previously reported on Id/anti-Id-receptor interactions in clinical human schistosomiasis. These findings support a hypothesis that anti-
SEA
cross-reactive Id develop in some patients during the course of a chronic infection and participate in regulation of anti-
SEA
cellular immune responses. We report here on experiments that extend those observations to the regulation of granulomatous hypersensitivity measured by an in vitro granuloma model. T cells from chronic intestinal schistosomiasis patients were stimulated in vitro with anti-
SEA
Id and assayed in an autologous in vitro granuloma assay for modulation of granuloma formation. These anti-
SEA
Id-reactive T cells were capable of regulating autologous in vitro granuloma formation. Both CD4 and CD8 T cells could be activated to regulate granuloma formation. This regulatory activity, initiated with stimulatory anti-
SEA
idiotypic antibodies, was antigenically specific and was dependent on the presence of intact F(ab')2 Ig molecules. The ability to elicit this regulatory activity appears to be dose dependent and is more easily demonstrated in chronically infected intestinal patients or
SEA
-sensitized individuals. These data support the hypothesis that anti-
SEA
cross-reactive Id are important in regulating granulomatous hypersensitivity in chronic intestinal schistosomiasis patients and these cross-reactive Id appear to play a major role in cell-cell interactions that result in the regulation of anti-
SEA
cellular immune responses.
J Immunol 1991
Dec
01
PMID:Granulomatous hypersensitivity to Schistosoma mansoni egg antigens in human schistosomiasis. II. In vitro granuloma modulation induced by polyclonal idiotypic antibodies. 194 Mar 77
The
MET
proto-oncogene encodes a transmembrane tyrosine kinase of 190 kDa (p190MET), which has recently been identified as the receptor for hepatocyte growth factor/scatter factor. p190MET is a heterodimer composed of two disulfide-linked chains of 50 kDa (p50 alpha) and 145 kDa (p145 beta). We have produced four different monoclonal antibodies that are specific for the extracellular domain of the Met receptor. These antibodies immunoprecipitate with p190MET two additional Met proteins of 140 and 130 kDa. The first protein (p140MET) is membrane bound and is composed of an alpha chain (p50 alpha) and an 85-kDa C-terminal truncated beta chain (p85 beta). The second protein (p130MET) is released in the culture supernatant and consists of an alpha chain (p50 alpha) and a 75-kDa C-terminal truncated beta chain (p75 beta). Both truncated forms lack the tyrosine kinase domain. p140MET and p130MET are consistently detected in vivo, together with p190MET, in different cell lines or their culture supernatants. p140MET is preferentially localized at the cell surface, where it is present in roughly half the amount of p190MET. The two C-terminal truncated forms of the Met receptor are also found in stable transfectants expressing the full-length
MET
cDNA, thus showing that they originate from posttranslational proteolysis. This process is regulated by protein kinase C activation. Together, these data suggest that the production of the C-terminal truncated Met forms may have a physiological role in modulating the Met receptor function.
Mol Cell Biol 1991
Dec
PMID:C-terminal truncated forms of Met, the hepatocyte growth factor receptor. 194 72
Metastatic colonization of a secondary organ site is initiated by the attachment of blood-borne tumor cells to organ-specific adhesion molecules expressed on the surface of microvascular endothelial cells. Using digital video imaging microscopy and fluorescence activated cell sorting techniques, we show here that highly metastatic cells (B16-F10 murine melanoma and R3230AC-
MET
rat mammary adenocarcinoma cells) previously labeled with the fluorescent dye BCECF begin to transfer dye to endothelial cell monolayers shortly after adhesion is established. The extent of BCECF transfer to endothelial cell monolayers is dependent upon the number of BCECF-labeled tumor cells seeded onto the endothelial cell monolayer and the time of coculture of the two cell types, as visualized by an increase in the number of BCECF-positive cells among cells stained with an endothelial cell-specific mAb. Dye transfer to BAEC monolayers proceeds with a progressive loss of fluorescence intensity in the BCECF-labeled tumor cell population with time of coculture. The transfer of dye is bidirectional and sensitive to inhibition by 1-heptanol. In contrast, poorly metastatic B16-F0 melanoma cells and non-metastatic R3230AC-LR mammary adenocarcinoma cells do not efficiently couple with vascular endothelial cells. It is inferred from these experiments and from the amounts of connexin43 mRNA expressed by tumor cells that tumor cell/endothelial cell communication is mediated by gap junctional channels and that this interaction may play a critical role in tumor cell extravasation at secondary sites.
J Cell Biol 1991
Dec
PMID:Cytoplasmic dye transfer between metastatic tumor cells and vascular endothelium. 195 78
Based on the high incidence of loss of heterozygosity for loci on chromosome 17p in the vicinity of the p53 locus in human breast tumors, we investigated the frequency and effects of mutations in the p53 tumor suppressor gene in mammary neoplasia. We examined the p53 gene in 20 breast cancer cell lines and 59 primary breast tumors. Northern blot analysis, immunoprecipitation, and nucleotide sequencing analysis revealed aberrant mRNA expression, over-expression of protein, and point mutations in the p53 gene in 50% of the cell lines tested. A multiplex PCR assay was developed to search for deletions in the p53 genomic locus. Multiplex PCR of genomic DNA showed that up to 36% of primary tumors contained aberrations in the p53 locus. Mutations in exons 5-9 of the p53 gene were found in 10 out of 59 (17%) of the primary tumors studies by single-stranded conformation polymorphism analysis. We conclude that, compared to amplification of
HER2
/NEU, MYC, or INT2 oncogene loci, p53 gene mutations and deletions are the most frequently observed genetic change in breast cancer related to a single gene. Correlated to disease status, p53 gene mutations could prove to be a valuable marker for diagnosis and/or prognosis of breast neoplasia.
Proc Natl Acad Sci U S A 1991
Dec
01
PMID:Mutations in p53 as potential molecular markers for human breast cancer. 196 33
The expression of p185ERBB2 in a total of 34 human gastric carcinoma tissues as well as in corresponding normal mucosa was examined by Western blotting. More than 70% of both tumor tissues and normal mucosa showed p185ERBB2 expression at various levels. Eighteen (55%) cases revealed higher levels of p185ERBB2 in the tumor than in normal mucosa, while 13 (38%) cases showed lower levels in the tumor tissues. Higher expression of p185ERBB2 was frequently observed in well differentiated adenocarcinomas, with the incidence between well differentiated type and poorly differentiated type being significantly different (P less than 0.05). Comparative immunohistochemical analysis revealed the consistent results with p185ERBB2 expression obtained by Western blotting in well differentiated adenocarcinomas. Of the 34 cases, three well differentiated adenocarcinomas had extremely high levels of p185ERBB2.
ERBB2
gene was amplified in two of the three tumors, but the amplification differed by the tumor site from where the sample was obtained. Another tumor which showed an extremely high level of p185ERBB2 but no gene amplification demonstrated a high level of binding protein to the TATA box that is located in the promoter of the
ERBB2
gene. A high level of TATA-binding protein was also detected in gastric carcinoma cell lines which contain a single copy of
ERBB2
gene and a high expression of p185ERBB2.
Cancer Res 1990
Dec
15
PMID:Expression of ERBB2 in human gastric carcinomas: relationship between p185ERBB2 expression and the gene amplification. 197 53
Trans-activation by the herpes simplex virus (HSV) protein, alpha
TIF
(VP16), is dependent on an inducible enhancer sequence that contains a homolog of the octamer element. An ordered series of multiprotein complexes can be assembled on this enhancer, requiring the interactions of Oct-1, alpha
TIF
, and two additional cellular factors (C1 and C2). Oct-1 binds to the octamer homolog, whereas alpha
TIF
, also a sequence-specific DNA-binding protein, recognizes sequences within the HSV enhancer core. The partially purified C1 factor interacts directly with alpha
TIF
in the absence of DNA and is required to form a stabile Oct-1/alpha
TIF
/C1 factor complex. The POU domain of Oct-1 is a bipartite sequence recognition structure, as both the POU-specific box and the POU homeo box contribute directly to the recognition of the octamer element. Surprisingly, the POU homeo box alone is sufficient to direct the cooperative binding of alpha
TIF
and to assemble the Oct-1/alpha
TIF
/C1 factor complex.
Genes Dev 1990
Dec
PMID:Interactions of the Oct-1 POU subdomains with specific DNA sequences and with the HSV alpha-trans-activator protein. 198 Jun 58
The Mr 185,000 glycoprotein encoded by human c-erbB-2/neu/
HER2
gene, termed c-erbB-2 gene product, shows a close structural similarity with epidermal growth factor receptor and is now regarded to be a growth factor receptor for an as yet unidentified ligand. Abundant c-erbB-2 mRNA was demonstrated by Northern blot studies in the human breast cancer cell line SK-BR-3. Cellular radiolabeling experiments followed by immunoprecipitation with three different anti-c-erbB-2 gene product antibodies, recognizing extracellular domain, kinase domain, and carboxyl-terminal portion, respectively, demonstrated the production of a large amount of c-erbB-2 gene product which had the capacity to be phosphorylated. Immunization of mice with concentrated culture medium conditioned by SK-BR-3 cells always generated antibodies against c-erbB-2 gene product, demonstrating that this culture medium contained substance(s) immunologically indistinguishable from c-erbB-2 gene product. This observation was supported by the successful development of a monoclonal antibody against c-erbB-2 gene product, GFD-OA-p185-1, by immunizing mice with this culture medium. The biochemical nature of the substance(s) present in the culture medium was further characterized. When the culture medium conditioned by [35S]cysteine-labeled SK-BR-3 cells was immunoprecipitated by three different anti-c-erbB-2 gene product antibodies, only the antibody recognizing extracellular domain precipitated the [35S]-labeled protein with a molecular weight of 110,000, namely p110. The newly developed monoclonal antibody also immunoprecipitated this protein.(ABSTRACT TRUNCATED AT 250 WORDS)
Cell Growth Differ 1990
Dec
PMID:The presence of c-erbB-2 gene product-related protein in culture medium conditioned by breast cancer cell line SK-BR-3. 198 Nov 43
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>