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)

Taxanes are effective in the treatment of metastatic breast cancer. Docetaxel has been shown to be more potent than paclitaxel in inducing bcl-2 phosphorylation and apoptosis and is clinically active in some paclitaxel-resistant breast tumors. HER-2/neu overexpression has been shown to correlate with resistance to hormonal therapy as well as chemotherapy. Using a HER-2/neu transfected MCF-7 human breast cancer cell line, we investigated the role of HER-2/neu overexpression on resistance to paclitaxel and docetaxel treatment. A control vector transfected MCF-7 human breast cancer cell line (MCF/neo) and a HER-2/neu transfected MCF-7 line (MCF/18) were treated with various concentrations of docetaxel or paclitaxel. Cell number was assessed using the MTT tetrazolium dye assay. In the control vector transfected MCF/neo cell line, paclitaxel and docetaxel gave similar dose-dependent growth inhibition ( p = 0.175). In HER-2/neu transfected MCF/18 cells, docetaxel treatment resulted in a dose-dependent inhibition similar to that seen in MCF/neo cells. Paclitaxel, however, gave significantly less growth inhibition than docetaxel in the HER-2/neu overexpressing MCF/18 cells (p = 0.0003). These data suggest that HER-2/neu overexpression may contribute to paclitaxel resistance. In contrast, the cytotoxic effects of docetaxel in these breast carcinoma cells are not affected by HER-2/neu expression. Therefore, docetaxel may be the preferred taxane therapy in HER-2/neu overexpressing breast tumors.
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PMID:Decreased response to paclitaxel versus docetaxel in HER-2/neu transfected human breast cancer cells. 1257 25

In this study we describe and discuss the dichotomous effects of docetaxel trastuzumab (Herceptin)/docetaxel therapy on the angiogenic molecular profile in two patients with her-2 + chemo-resistant recurrent breast carcinoma. In the first case, an intensification of angiogenesis occurred following therapy, accompanied by an impressive increase of the cancer cell proliferation index. This tumor did not express HIF1 alpha and shared a HIF-independent VEGF overexpression, which remained unaffected by therapy. An intensified formation of thymidine phosphorylase (TP)-rich stroma, presumably a response to docetaxel, shows a TP-dependent angiogenic response. In the second patient, VEGF and HIF1 alpha were down-regulated in post-treatment biopsies and this was accompanied by a sharp reduction of the vascular density and of the cancer cell proliferation rate. In both cases, c-erbB-2 expression was abrogated by Herceptin. Taking into account that Herceptin down-regulates VEGF through reduction of HIF1 alpha synthesis, this clinical study provides evidence that an anti-angiogenic effect from Herceptin/Docetaxel therapy is expected only in tumors with HIF1 alpha-dependent VEGF overexpression. In contrast, HIF1 alpha-independent VEGF angiogenic activity cannot be abrogated by Herceptin. Docetaxel mediated up-regulation of TP in the tumoral stroma may, on the contrary, result in angiogenesis intersification and rapid tumor relapse. Such an effect should be of clinical importance since Herceptin/Docetaxel-based regimens are currently evaluated for the adjuvant therapy of her-2 + breast cancer patients. Studying the Herceptin-induced phenotypic changes of tumors could lead to the identification of specific molecular profiles that bring about diverging angiogenic responses. Adjustment of the chemotherapy regimen accordingly would prove of clinical importance.
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PMID:The effect of trastuzumab/docatexel combination on breast cancer angiogenesis: dichotomus effect predictable by the HIFI alpha/VEGF pre-treatment status? 1282 Apr 39

Docetaxel is one of the most promising chemotherapeutic agents for the treatment of metastatic breast cancer, but it shows fearful side effects. We hypothesized that a novel targeted nanoassembly (TNA) could provide efficient intracellular drug delivery in breast tumor cells overexpressing epidermal growth factor (EGF) receptor and thus improve the efficacy and reduce the side effects of docetaxel. We prepared the novel docetaxel loaded TNAs formed by polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE) and modified with EGF. Compared with nontargeted nanoassemblies (NNAs), TNAs showed obvious improvement of cell-specific uptake and internalization, and revealed more cytotoxicity against MDA-MB-468 cells by inducing more late apoptosis and subG1 cells at low drug concentration, or more G2/M arrest at high drug concentration than NNAs or Taxotere. In BALB/c mice bearing breast tumor xenografts, TNAs showed stronger inhibition of tumor growth compared with NNAs (relative tumor volume in mice treated with 5 mg/kg TNAs = 0.99 and 10 mg/kg NNAs = 1.71, p < 0.05) or Taxotere (relative tumor volume in mice treated with 5 mg/kg TNAs = 0.99 and 10 mg/kg Taxotere = 4.20, p < 0.01). In particular, tumor disappeared completely in the TNA group at a dose of 10 mg/kg. The maximum tolerated dose (MTD) of TNAs was about four times higher than that of Taxotere. TNAs also demonstrated a much longer circulation time in vivo and more drug accumulation in tumor in a murine breast cancer model than Taxotere. TNA treatment also prolonged survival of mice. These results suggested that TNAs could have more potential as a delivery system for breast cancer chemotherapy.
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PMID:Targeted nanoassembly loaded with docetaxel improves intracellular drug delivery and efficacy in murine breast cancer model. 1943 22