Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A murine IgM monoclonal antibody, designated SV2-61, was generated against human c-erbB-2 gene-transfected NIH-3T3 (SV11) cells. SV2-61 defined a 185-kDa molecule present on the surface of SV11 cells, another line of c-erbB-2 gene-transfected NIH-3T3 (A4-15) cells, and MKN-7 human gastric cancer cell line carrying an amplified human c-erbB-2 gene. The SV2-61-defined antigen was found to show protein kinase activity in vitro. The SV2-61 was reactive with human c-erbB-2 gene-transfected NIH-3T3 cell lines but not with transfectants carrying c-erbB-2 gene mutants which lack a coding region for the extracellular domain. It was reactive with a portion of human epithelial cell lines but not with native NIH-3T3, TGF-alpha-coding gene-, activated c-raf gene- or Ha-ras gene-transfected NIH-3T3 cells, or non-epithelial human cells. These results indicate that the SV2-61 is an antibody which recognizes an extracellular domain of the c-erbB-2 gene product, 185-kDa protein.
 ...
PMID:A murine monoclonal antibody that recognizes an extracellular domain of the human c-erbB-2 protooncogene product. 256 25

We have previously reported the immunohistochemical localization of transforming growth factor-alpha (TGF alpha) in the intact bovine anterior pituitary gland. Furthermore, we have purified TGF alpha from the conditioned medium of cell cultures derived from the bovine anterior pituitary. We report her the identification of the TGF alpha mRNA from both the intact bovine anterior pituitary gland and the anterior pituitary derived cell cultures. The level of TGF-alpha mRNA in the cell cultures is greater than that present in the intact gland. The TGF-alpha mRNA level increased when the cell cultures were allowed to incubate in their conditioned medium for 3 days, suggesting that a secretory product from the cultured cells is capable of stimulating the accumulation of the TGF-alpha mRNA. 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation of these cells resulted in a 6-fold increase in the level of TGF-alpha secreted into the conditioned medium. TPA appears to stimulate TGF-alpha secretion at the level of gene transcription as TPA treatment also resulted in an increased accumulation of the TGF-alpha mRNA. The epidermal growth factor (EGF) receptor mRNA was examined in these cell cultures and it increased with TPA treatment in an analogous manner to the TGF-alpha mRNA. EGF treatment of the pituitary cells resulted in an increased level of TGF-alpha mRNA which followed the same time course as TPA, maximal stimulation occurred after 8 h of treatment. The magnitude of EGF stimulated TGF-alpha mRNA was not as great as that seen by TPA stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Transforming growth factor-alpha expression in the anterior pituitary gland: regulation by epidermal growth factor and phorbol ester in dispersed cells. 278 91

The epidermal growth factor (EGF) receptor mediates the induction of a transformed phenotype in normal rat kidney (NRK) cells by transforming growth factors (TGFs). The ability of EGF and its analogue TGF-alpha to induce the transformed phenotype in NRK cells is greatly potentiated by TGF-beta, a polypeptide that does not interact directly with binding sites for EGF or TGF-alpha. Our evidence indicates that TGF-beta purified from retrovirally transformed rat embryo cells and human platelets induces a rapid (t 1/2 = 0.3 h) decrease in the binding of EGF and TGF-alpha to high-affinity cell surface receptors in NRK cells. No change due to TGF-beta was observed in the binding of EGF or TGF-alpha to lower affinity sites also present in NRK cells. The effect of TGF-beta on EGF/TGF-alpha receptors was observed at concentrations (0.5-20 pM) similar to those at which TGF-beta is active in promoting proliferation of NRK cells in monolayer culture and semisolid medium. Affinity labeling of NRK cells and membranes by cross-linking with receptor-bound 125I-TGF-alpha and 125I-EGF indicated that both factors interact with a common 170-kD receptor structure. Treatment of cells with TGF-beta decreased the intensity of affinity-labeling of this receptor structure. These data suggest that the 170 kD high-affinity receptors for EGF and TGF-alpha in NRK cells are a target for rapid modulation by TGF-beta.
 ...
PMID:Transforming growth factor-beta modulates the high-affinity receptors for epidermal growth factor and transforming growth factor-alpha. 298 23

The c-erbB-2 gene was first identified by virtue of its cross-hybridization with v-erbB. Nucleotide sequence analysis of complementary DNA clones suggested that the c-erbB-2 gene encodes a growth factor receptor similar to that for EGF. Antibodies against the carboxyl terminal sequence of the c-erbB-2 protein immunoprecipitated a 185-kDa glycoprotein which showed protein-tyrosine kinase activity in vitro. Despite the extensive similarity between the c-erbB-2 protein and EGF receptor, neither EGF nor TGF-alpha bound to the c-erbB-2 protein. Phosphorylation of the c-erbB-2 protein was stimulated by TPA via protein kinase C in vivo. EGF also induced phosphorylation of the c-erbB-2 protein. This phosphorylation occurred not only on serine and threonine residues but also on tyrosine residues. Preliminary data suggested that the latter was mediated by the kinase activity of the EGF receptor. Southern blot analysis of DNAs from primary tumors revealed that the c-erbB-2 gene tends to be amplified in adenocarcinomas, mostly of the stomach and the breast. By screening both human genomic and cDNA libraries using v-yes DNA as a probe, we obtained DNA clones of the c-yes gene, the pseudogene of c-yes, c-fgr gene and c-src gene and two novel yes-related genes, fyn and lyn. Complete nucleotide sequence analysis of the cDNA clones of c-yes, fyn and lyn revealed that these genes encode proteins similar to p60src both in size and sequence.
 ...
PMID:[The erbB-related protooncogenes encoding growth factor receptors]. 349 52

We previously demonstrated that occupancy of the epidermal growth factor (EGF) receptor reduced the ability of vaccinia virus to infect L cells [Eppstein et al: Nature 318:663, 1985]. This result suggested that vaccinia virus was utilizing the EGF receptor as one pathway to infect cells. We have studied this system further, and now find that antibodies to the EGF receptor also reduce the ability of vaccinia virus to infect cells productively. Inclusion of both EGF and antibodies to the EGF receptor did not cause inhibition over that obtained by EGF alone, providing another line of evidence that the antiviral effects on vaccinia virus were at the level of the EGF receptor. The antiviral effects of EGF or synthetic peptides corresponding to the third disulfide loop of TGF-alpha or the vaccinia virus growth factor were specific to vaccinia virus and did not inhibit replication of herpes simplex virus type 2 or vesicular stomatitis virus. The inhibitory effects on replication of vaccinia virus were obtained when EGF (but not insulin or growth hormone) was present prior to, but not after, productive viral adsorption. These results provided further evidence that the antivaccinia viral effects of EGF were at the level of initial receptor occupancy. As interferon (IFN) treatment has been shown to interfere with the action of some growth factors, including EGF, we examined the effects of IFN treatment of cells on the antivaccinia viral activity of EGF. Our results show that the antivaccinia effect of IFN-beta either interfered with or partially coalesced with the inhibitory effects of EGF.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Vaccinia virus and the EGF receptor: a portal for infectivity? 349 35

Previous work showed that cultured human pancreatic cancer cells overexpress the epidermal growth factor (EGF) receptor. In the present study, we sought to determine whether some of these cell lines produce transforming growth factor alpha (TGF-alpha). Utilizing a radiolabeled TGF-alpha cDNA in hybridization experiments, we determined that ASPC-1, T3M4, PANC-1, COLO-357, and MIA PaCa-2 cell lines expressed TGF-alpha mRNA. Serum-free medium conditioned by T3M4 and ASPC-1 cells contained significant amounts of TGF-alpha protein. Although unlabeled TGF-alpha readily competed with 125I-labeled EGF for binding, each cell line exhibited lower surface binding and internalization of 125I-labeled TGF-alpha as compared to 125I-labeled EGF. Both TGF-alpha and EGF significantly enhanced the anchorage-independent growth of PANC-1, T3M4, and ASPC-1 cells. However, TGF-alpha was 10- to 100-fold more potent than EGF. These findings suggest that the concomitant overexpression of EGF receptors and production of TGF-alpha may represent an efficient mechanism for certain cancer cells to obtain a growth advantage.
 ...
PMID:Production of transforming growth factor alpha in human pancreatic cancer cells: evidence for a superagonist autocrine cycle. 349 10

Mouse monoclonal antibodies to the human epidermal growth factor (EGF) receptor were raised by immunizing with plasma membrane vesicles prepared from A431 cells. This paper describes the characterization of one of the IgG anti-receptor monoclonal antibodies generated and its use to probe the role of transforming growth factor (TGF) in the autonomous growth of a melanoma cell line in culture. This antibody blocks: 1) the binding of 125I-EGF to the A431 EGF receptor; 2) the EGF stimulation of the EGF-dependent protein kinase in vitro; and 3) human fibroblast DNA synthesis and proliferation in culture. It can precipitate the EGF receptor from metabolically labeled A431 cells and human fibroblasts and these receptors have indistinguishable peptide maps. No EGF receptor could be detected by immunoprecipitation after fibroblasts were treated with EGF or conditioned medium from the melanoma cells which secrete EGF-like TGF (alpha TGF). The antibody itself did not down-regulate the receptor but could block down-regulation caused by EGF and alpha TGF. Despite its ability to block EGF-stimulated growth and down-regulation in fibroblasts, the antibody was unable to block the growth and soft agar colony formation of alpha TGF-secreting melanoma cells, nor could the antibody detect EGF receptor in these cells under the conditions developed to prevent down-regulation and lysosomal degradation of the EGF receptor. These studies suggest that these melanoma cells do not have the intact EGF receptor and that the secretion of alpha TGF by these cells plays no role in their growth in culture. The absence of receptor cannot be explained by down-regulation by secreted alpha TGF.
 ...
PMID:Inability of anti-epidermal growth factor receptor monoclonal antibody to block "autocrine" growth stimulation in transforming growth factor-secreting melanoma cells. 609 Apr 50

Limited information is available concerning the involvement of growth factor receptors and their ligands in the pathogenesis of human pancreatic cancer. We analyzed 12 human pancreatic cancer cell lines by Northern blot analysis for the expression of 9 receptor tyrosine kinase (RTKs) and 6 growth factors. The effect of a monoclonal antibody (MAb) against transforming growth factor-alpha (TGF-alpha) on in vitro pancreatic cancer cell growth was also assessed, mRNA for EGF-R, c-erbB-2 and c-erbB-3 was expressed in 12 (100%), 12 (100%), and 7 (58%), respectively, of the cell lines examined. In addition, 8 (67%) cell lines expressed the c-met/receptor for hepatocyte growth factor. As for ligands, TGF-alpha mRNA was detected in 10 (83%) cell lines; MAb against TGF-alpha inhibited growth of the 2 cell lines examined. Furthermore, mRNA for amphiregulin (AR) was expressed in 10 (83%) cell lines. Coexpression of TGF-alpha, AR, and EGF-R was observed in 9 (75%) cell lines. These results support the concept that several specified types of RTKs and their ligands are closely involved in regulation of the growth of human pancreatic cancer cells.
 ...
PMID:Frequent expression of genes for receptor tyrosine kinases and their ligands in human pancreatic cancer cells. 759 66

The Drosophila homologue of the mammalian epidermal growth factor (EGF) receptor (DER) is a receptor tyrosine kinase involved in many stages of fly development, including photoreceptor determination, and wing-vein formation. Its primary activating ligand is the Spitz protein, which is similar to mammalian TGF-alpha. Argos is a secreted protein that, like Spitz, contains a single EGF motif. It is a repressor of cell determination in the eye, and acts in other tissues, including the wing. Because Argos has the opposite effects to DER in the eye (the former blocks photoreceptor determination, the latter promotes it) we have tested whether it acts by blocking the DER pathway. We show that Argos does indeed repress this pathway in vivo and find that, in vitro, Argos protein can inhibit the activation of DER by Spitz. Thus the determination of cells by the DER pathway is regulated by a balance between extracellular activating and inhibiting signals. This is the first in vivo example of an extracellular inhibitor of a receptor tyrosine kinase.
 ...
PMID:Inhibition of Drosophila EGF receptor activation by the secreted protein Argos. 765 19

mRNA amplification phenotyping (MAPPing) was used to determine the level of mRNA expression of the major EGF-related ligands (EGF, TGF-alpha, and Amphiregulin) and receptors (EGF-receptor and erbB-2) of the EGF supergene family in three ovarian carcinoma lines (OVCA 429 and 433, and NIH:OVCAR-8) under serum-supplemented and reduced serum (minimal medium with 2% fetuin) growth conditions. mRNA levels of TGF-alpha, EGF-R, and erbB-2 were particularly high, and increased approximately 2-3 orders of magnitude when grown in serum, consistent with an autocrine involvement of these genes in ovarian epithelial growth in vitro. Moreover, even when grown without serum, OVCA 429 and NIH:OVCAR-8 expressed elevated levels of mRNA for erbB-2.
 ...
PMID:mRNA phenotyping of the major ligands and receptors of the EGF supergene family in human ovarian epithelial cells. 788 3


<< Previous 1 2 3 4 5 6 Next >>