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

The epidermal growth factor (EGF) receptor plays a pivotal role in growth regulation of epidermal keratinocytes. Its expression and function can be markedly altered during malignant transformation in squamous cell carcinoma. The present study investigated the potential of growth inhibition by signal-transduction inhibitors in EGF-dependent epithelial cell lines in vitro. Benign HaCaT keratinocytes and malignant A431 cells were grown in vitro and exposed to various concentrations of a panel of eleven kinase and phosphodiesterase inhibitors. Cell growth was measured after 24 h and 48 h using fluorescence labeling with Hoechst 33342 and propidium iodide. Significant growth inhibition was achieved with all inhibitors when applied to HaCaT cells. The strongest growth inhibition was achieved with inhibitors H-7, A3 and diacylglycerol kinase inhibitors I and II. A431 cells were inhibited significantly by H-7, A3 and H-9. Selected signal-transduction inhibitors such as A3, H-7 and H-9 acting on intracellular kinases are capable of suppressing growth of EGF-dependent benign and malignant epithelial cell lines in vitro. They might be of future potential in the treatment of epithelial cancer but further studies are necessary.
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PMID:Inhibition of signal transduction in EGF-dependent epithelial cell lines. 1296 53

The effects of HER-2/neu overexpression on the tumor microenvironment in an aggressive breast cancer xenograft model were investigated. These studies focused on tumors derived following the subcutaneous injection of MDA-MB-435/LCC6 cells transfected with human c-erbB2 (LCC6(HER-2)) into SCID-Rag2M mice. LCC6(HER-2) tumors were more viable (H&E-stained tumor sections) than isogenic vector control tumors (LCC6(Vector)). Correspondingly, a 2.7-fold increase in trypan blue-excluding cells (P = 0.00056) and a 4.8-fold increase in clonogenic cells (P = 0.00146) were noted in cell suspensions derived from disaggregated LCC6(HER-2) versus LCC6(Vector) tumors. Tumor sections stained with the antibody detecting 2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl)-acetamide (EF5), a marker of hypoxia, showed a greater fraction of hypoxic tissue in LCC6(HER-2) tumors compared with control tumors. Flow cytometric analyses based on viable tumor cells (DNA content >/= 2N) in cell suspensions from disaggregated tumors confirmed that there were significantly more EF5-positive cells (i.e., hypoxic) in LCC6(HER-2) than in LCC6(Vector) tumors (16.41 +/- 8.1% and 5.96 +/- 4.1%, respectively; P = 0.0015). Protein levels of phosphorylated (Ser(536)) nuclear factor-kappaB p65 were significantly elevated in LCC6(HER-2) tumors (P = 0.00048), and a trend in increased hypoxia-inducible factor-1alpha protein levels was observed in LCC6(HER-2) compared with LCC6(Vector) tumors. Despite the substantial viable hypoxic cell fraction and a 1.7-fold increase of vascular endothelial growth factor protein (P = 0.05) in LCC6(HER-2) tumors, no significant differences were found (P > 0.05) between LCC6(HER-2) and LCC6(Vector) vasculature (CD31 staining and Hoechst 33342 perfusion). These results suggest that HER-2/neu overexpression may be linked with overall increased tumor viability and a significant increase in the population of viable hypoxic cells, which is not due to differences in tumor vascularization.
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PMID:HER-2/neu overexpression increases the viable hypoxic cell population within solid tumors without causing changes in tumor vascularization. 1556 77