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)

The effect of PTH on the epidermal growth factor (EGF) receptor was analyzed during the in vitro differentiation of human cytotrophoblasts. The cytotrophoblasts were isolated by a trypsin-DNase method from first trimester and term placentas and purified on a Percoll gradient. In culture, these cells aggregated and fused together to form a syncytium. This in vitro differentiation was associated with a 2-fold increase in 125I-EGF binding after 48 h of culture. The addition of 0.1 microM PTH (PTH-treated cells) to the culture medium induced a significant 2- to 3-fold increase (P less than 0.005) in EGF binding. The effect was dose related with a maximum obtained at a 1 nM concentration. Scatchard analyses revealed that PTH-treated cells possess a 2-fold higher number of high affinity sites as compared to control cells from early placenta (0.71 +/- 0.06 pmol/mg protein and 0.34 +/- 0.04 pmol/mg protein, respectively) and from term placenta (1.24 +/- 0.10 pmol/mg protein and 0.61 +/- 0.07 pmol/mg protein, respectively). The apparent Kd values for high affinity sites (0.15 nM) and for low affinity sites (4 nM) were not altered either by the gestational age of the cells or by PTH treatment. With respect to the EGF-dependent phosphorylation in membranes of trophoblast cells in culture, it was found that the phosphorylation of two major proteins of 175 kilodaltons and 35 kilodaltons, is greatly increased in PTH-treated cell membranes in the presence of EGF. This PTH-induced effect on EGF receptors was associated with an augmented functional response of trophoblastic cells to EGF. PTH increased the EGF-stimulated secretion of hCG. These results demonstrate that PTH increases the number of biologically active EGF receptors during the in vitro differentiation of human trophoblast cells. This PTH-induced effect suggests a role for this hormone in the regulation of the growth and the endocrine functions of these cells.
 ...
PMID:Parathyroid hormone increases epidermal growth factor receptors in cultured human trophoblastic cells from early and term placenta. 185 60

Human epidermal growth factor (EGF) receptor mRNA was detected in cryopreserved tissue sections adherent to whole glass slides using in situ reverse transcriptase polymerase chain reaction. EGF receptor cDNA was synthesized in situ by reverse transcription using an EGF receptor-specific oligonucleotide primer. In situ polymerase chain reaction amplification in the presence of digoxigenin-11-dUTP and subsequent binding with an antidigoxigenin antibody conjugated to alkaline phosphatase allowed direct visualization. Because DNase, RNase, or proteinase K are not required, tissue integrity is maintained. EGF receptor mRNA is expressed in the basal layer of normal human skin epithelium and is significantly overexpressed in squamous cell tumor specimens, which is consistent with conventional analysis of EGF receptor expression. The assay is semiquantitative, quicker, more sensitive, and void of the nonspecific binding associated with in situ hybridization. In situ reverse transcriptase polymerase chain reaction using whole glass slides is ideally suited for detecting moderate to infrequently expressed transcripts in biopsy specimens.
 ...
PMID:Detection of epidermal growth factor receptor mRNA in tissue sections from biopsy specimens using in situ polymerase chain reaction. 808 54

We describe a sensitive and practical in situ hybridization method, using a digoxigenin-labeled probe, for the detection of c-erbB-2 amplification in breast cancer in formalin-fixed, paraffin-embedded tissue sections. Forty-six primary breast carcinomas were studied. Nuclear hybridization signal was observed in 36 of 46 carcinomas. Signal was confined to malignant cells. Normal breast epithelium and stromal and inflammatory cells were uniformally negative. DNase predigestion, no-probe preparations, and competitive hybridization confirmed the specificity of the reaction. The hybridization reaction was localized to multiple discrete foci in tumor cell nuclei, suggesting multiple sites of gene copy and transcriptional activity in the nucleus. Considerable cell-to-cell variation in hybridization signal was evident within individual tumors and positive reactions were observed in several cases in which amplification could not be detected by either Southern or slot blot analysis. The high sensitivity and specificity of the reaction and its use in a tissue-based system will allow the study of a range of possible precursor lesions of breast cancer for evidence of c-erbB-2 amplification.
 ...
PMID:c-erbB-2 amplification in breast cancer: detection in formalin-fixed, paraffin-embedded tissue by in situ hybridization. 790 7

Chromatin in interphase nuclei exhibits a topology that is associated with the transcriptional state of cells. We examined the spatial, intranuclear distribution of chromosome 17 and the ERBB-2 (HER2/neu) sequence thereon, relative to that of DNase-hypersensitive chromatin (DHC), in breast tumour cells exhibiting different levels of expression of ERBB-2. These sequences were specifically associated with the nuclear periphery, within a band of DHC. The remainder of the chromosome 17 mass showed no preferential position within the nucleus. The peripheral placement of ERBB-2 sequences is associated with a specific conformation of chromosome 17. We propose that the conformational organization of chromosome territories might represent a fundamental control mechanism in gene expression.
 ...
PMID:A specific conformation of the territory of chromosome 17 locates ERBB-2 sequences to a DNase-hypersensitive domain at the nuclear periphery. 960 77