Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:O76050 (neu)
 3,969 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The overexpression of the proto-oncogene HER-2 (c-erbB-2/neu) in ovarian and mammary carcinoma is an important indicator for a bad prognosis. In this study we demonstrate that in 7 out of 8 ovarian carcinoma cell lines there is an interferon-gamma-mediated reduction in HER-2 specific protein, and this effect was found to correlate with the antiproliferative action. It is interesting to note that there is no relationship between the absolute amount of HER-2 protein expressed and the sensitivity of the ovarian carcinoma cells for an antiproliferative activity of interferon-gamma. Other chemotherapeutic agents did not affect HER-2 expression although they inhibited the proliferation. The oncogene expression was lowered only in the ovarian carcinoma cell lines and not in 3 interferon-gamma sensitive human breast cancer cell lines. Expression of the oncogene HER-2 is the leading prognostic factor in ovarian cancer. Its modulation might represent a mechanism by which interferon-gamma inhibits cell proliferation.
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PMID:[Interferon-gamma suppresses expression of the HER-2 oncogene in ovarian cancer cells]. 135 79

The over-expression of the proto-oncogene HER-2 (c-erbB-2/neu) in ovarian, endometrial and mammary carcinoma is an important indicator for poor prognosis. We have previously shown in 3 out of 4 ovarian carcinoma cell lines an interferon-gamma (IFN-gamma)-mediated reduction in HER-2 specific protein and RNA levels. The oncogene expression was lowered only in the ovarian carcinoma cell lines but not in 3 IFN-gamma-sensitive human breast cancer cell lines. We extended our observations also to IFN type I, alpha and omega. The expression of the oncogene was measured by both the p185HER-2 ELISA and in selected cases by a living cell radioimmunoassay using the monoclonal antibody (MAb) 4D5 against the extracellular domain. Both IFN types reduced the expression of HER-2 in the ovarian carcinoma cell lines OVCAR-3, HTB-77, 2774 and SKOV-6, and in the SKUT-2 endometrial carcinoma cells. In contrast, SKOV-8 human ovarian carcinoma cells were sensitive for both IFN types regarding proliferation, but only IFN-gamma reduced proto-oncogene expression. In the SKBR-3 human mammary carcinoma cells, neither IFN type had an effect on HER-2 expression. The antibodies 4D5, 7C2, 3E8, and 3H4 which bind to the extracellular domain of p185HER-2 protein specifically inhibited anchorage-independent growth of SKBR-3 and HTB-77 cells. Expression of the oncogene HER-2 is the leading prognostic factor in ovarian cancer. Its modulation might represent a mechanism by which IFNs inhibit cell proliferation.
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PMID:Effects of interferons on the expression of the proto-oncogene HER-2 in human ovarian carcinoma cells. 137 Feb 27

Polypeptide growth factors and cytokines mediate their biochemical functions through their responsive receptors. Known cytokine receptors do not possess intrinsic kinase domains whereas several polypeptide growth factor receptors do. Nevertheless, both classes of ligands are capable of activating sets of overlapping genes. In human epidermoid carcinoma cells, for example, both cytokines and epidermal growth factor (EGF) promote a common transcriptional activation signal through the tyrosine phosphorylation of stat91 (signal transducer and activator of transcription) proteins. The stat family of cytoplasmic proteins also appear to have dual functions. Tyrosine phosphorylated 'stats' are employed for signal transduction and, second, for activation of transcription of several genes. The transcription factor-SIE-DNA binding patterns are now known to be different for EGF and interferon-gamma IFN-gamma-treated cells. Nevertheless, in the active DNA-bound complex, the stat91 polypeptide is a component found in either EGF or INF-gamma-treated extracts. Other stat family members of transcription factors may also be present in the complexes. In this case, tyrosine phosphorylated stat91 polypeptides may form into homodimeric or heterodimeric assemblies with other stat-related transcription factors. We describe a novel stat-related factor, p93, that is found in EGF-treated A431 cell extracts but appears to be absent in bovine fibroblast growth factor (bFGF), IFN-gamma, tumor necrosis factor-alpha (TNF-alpha), and untreated cells. p93 appears to be antigenically related to stat91. p185c-neu+, EGFr+ (M1), and p185c-neu- kinase inactive, EGFr+ (NEN757) expressing cells undergo different mitotic responses to EGF. M1 can respond to EGF mitotically while NEN757 cannot. Both cell lines respond to 10 ng/ml of EGF and also to IFN-gamma in transducing transcriptional activation signals to the nucleus, despite the distinct growth response to EGF. Our work has analyzed the stat pathway in these types of cells and found similar patterns of usage despite the distinct EGF-responsive features. Cytoplasmic nonreceptor tyrosine kinases Jak1 and Jak2 may be involved in the activation of stat91 and other transcription factors in EGF and IFN-gamma signaling pathways. Collectively, these studies suggest that the major EGF-stimulated mitotic growth pathways may not be absolutely linked to the stat91 signaling pathways and that such transcription complexes are more complex than previously reported.
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PMID:Unexpected transcriptional signals in normal and mitotically defective cells mediated through cytokine and growth factor receptors. 757 78

While some tumor cells are sensitive to the antiproliferative effects of tumor necrosis factor (TNF), others are resistant. The molecular basis for cellular resistance to TNF is not completely understood. Previously we have shown that transfection of cells with an oncogene HER2/neu/erb B2, a receptor tyrosine kinase, leads to resistance to the anticellular effects of TNF [(1988) Proc. Natl. Acad. Sci. USA 85, 5102-5106]. In the present study, we demonstrate that the overexpression of another oncogenic tyrosine kinase, pp60v-src also induces resistance to TNF. In contrast to HER2, however, pp60v-src transfection of cells did not lead to down-modulation of TNF receptors but rather to decreased intracellular glutathione levels. The pp60v-src-induced cellular resistance to TNF could be abrogated by interferon-gamma. Thus, these results indicate that the resistance of certain tumors to TNF may also be due in part to the overexpression of pp60v-src oncogene.
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PMID:pp60v-src kinase overexpression leads to cellular resistance to the antiproliferative effects of tumor necrosis factor. 791 Oct 89

Dendritic cells (DCs) are bone marrow-derived leukocytes that function as potent antigen presenting cells capable of initiating T cell-dependent responses from quiescent lymphocytes. DC pulsed with tumor-associated antigen (TAA) peptide or protein have recently been demonstrated to elicit antigen-specific protective antitumor immunity in a number of murine models. Transduction of DCs with TAA genes may allow stable, prolonged antigen expression as well as the potential for presentation of multiple, or unidentified, epitopes in association with major histocompatibility complex class I and/or class II molecules. To evaluate the potential efficacy of retrovirally transduced DCs, bone marrow cells harvested from BALB/c mice were transduced with either a model antigen gene encoding beta-galactosidase (beta-gal) or a control gene encoding rat HER-2/neu (Neu) by coculture with irradiated ecotropic retroviral producer lines. Bone marrow cells were differentiated into DC in vitro using granulocyte/macrophage colony-stimulating factor and interleukin-4. After 7 d in culture, cells were 45-78% double positive for DC phenotypic cell surface markers by FACS(R) analysis, and DC transduced with beta-gal were 41-72% positive for beta-gal expression by X-gal staining. In addition, coculture of beta-gal transduced DC with a beta-gal-specific T cell line (CTLx) resulted in the production of large amounts of interferon-gamma, demonstrating that transduced DCs could process and present endogenously expressed beta-gal. DC transduced with beta-gal and control rat HER-2/neu were then used to treat 3-d lung metastases in mice bearing an experimental murine tumor CT26.CL25, expressing the model antigen, beta-gal. Treatment with beta-gal-transduced DC significantly reduced the number of pulmonary metastatic nodules compared with treatment with Hank's balanced salt solution or DCs transduced with rat HER-2/neu. In addition, immunization with beta-gal-transduced DCs resulted in the generation of antigen-specific cytotoxic T lymphocytes (CTLs), which were significantly more reactive against relevant tumor targets than CTLs generated from mice immunized with DCs pulsed with the Ld-restricted beta-gal peptide. The results observed in this rapidly lethal tumor model suggest that DCs transduced with TAA may be a useful treatment modality in tumor immunotherapy.
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PMID:Dendritic cells retrovirally transduced with a model antigen gene are therapeutically effective against established pulmonary metastases. 933 60

Relapse after adjuvant chemotherapy or high-dose chemotherapy with stem cell transplant for high-risk breast cancer remains high and new strategies that provide additional antitumor effects are needed. This report describes methods to generate highly effective HER2/neu-specific cytotoxic T cells by arming activated T cells with anti-CD3 x anti-HER2/neu bispecific antibody (BsAb). OKT3 and 9184 (anti-HER2) monoclonal antibodies (mAb) were conjugated and used to arm T cells that were subsequently tested in binding, cytotoxicity, and cytokine secretion assays. Armed T cells aggregated and specifically killed HER2/neu(+) breast cancer cells. Cytotoxicity emerged after 6 days of culture, was higher in armed T cells than unarmed T cells at all effector to target ratios (E/T) tested, and increased as the arming dose was increased. At an E/T of 20:1, the mean cytotoxicity of armed activated T cells (ATC) from 10 normal subjects increased by 59 +/- 11% (+/-SD) over that seen in unarmed ATC (p < 0.001) and the mean cytotoxicity of armed ATC from 6 cancer patients increased by 32 +/- 9% above that seen for unarmed ATC (p < 0.0004). After arming, the BsAb persisted on ATC up to 72 h and armed ATC continued to be cytotoxic up to 54 h. The amount of interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF) secreted was 1699, 922, and 3092 pg/ml/10(6) cells per 24 h, respectively, when armed T cells were exposed to a HER2/neu(+) breast carcinoma cell line. These studies show the feasibility and clinical adaptability of this approach for generating large numbers of anti-HER2-specific, cytotoxic T cells for clinical trials.
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PMID:Use of anti-CD3 x anti-HER2/neu bispecific antibody for redirecting cytotoxicity of activated T cells toward HER2/neu+ tumors. 1135 72

The gene for HER2/neu is overexpressed in 30-40% of breast and ovarian cancers, and this overexpression correlates with increased metastasis and poor prognosis. The HER2/neu gene product, a transmembrane protein kinase member of the EGF receptor family, has significant potential as a tumor antigen for vaccination. We inserted the sequence for neu into a novel plasmid called ELVIS containing a Sindbis virus replicon that reproduces multiple copies of mRNA. Mice vaccinated one time intramuscularly demonstrated a strong antibody response against A2L2, a murine breast cancer cell line transfected to express neu. Vaccinated mice challenged in the mammary fatpad with A2L2 had reduced tumor incidence and reduced tumor mass compared to mice challenged with tumor cells lacking the neu insert. Intradermal vaccination was also protective and required 80% less plasmid for a similar level of protection. Vaccination reduced the incidence of lung metastasis from mammary fatpad tumors and reduced the number of lung metastases resulting from intravenous injection of A2L2 cells. Cytotoxic T lymphocytes cultures of immune spleen cells with P815-neu cells produced high levels of interferon-gamma indicating an antigen-specific Th1-type immune response resulting from the vaccination. In a spontaneous breast tumor model using neu transgenic mice, vaccination with ELVIS-neu protected against development of spontaneous breast tumors. Our preclinical data indicate that therapeutic vaccination of patients with ELVIS-neu may reduce metastasis from HER2/neu-expressing breast and ovarian tumors.
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PMID:DNA vaccination against neu reduces breast cancer incidence and metastasis in mice. 1139 78

The identification and characterization of tumor antigens has facilitated the development of immune-based cancer prophylaxis and therapy. Cancer vaccines, like viral vaccines, may be effective in cancer prevention. Adoptive T-cell therapy, in contrast, may be more efficacious for the eradication of existing malignancies. Our group is examining the feasibility of antigen-specific adoptive T-cell therapy for the treatment of established cancer in the HER2/neu model. Transgenic mice overexpressing rat neu in mammary tissue develop malignancy, histologically similar to human HER2/neu-overexpressing breast cancer. These mice can be effectively immunized against a challenge with neu-positive tumor cells. Adoptive transfer of neu-specific T cells into tumor-bearing mice eradicates malignancy. Effective T-cell therapy relies on optimization of the ex vivo expansion of antigen-specific T cells. Two important elements of ex vivo antigen-specific T-cell growth that have been identified are (1) the preexisting levels of antigen-specific T cells and (2) the cytokine milieu used during ex vivo expansion of the T cells. Phase I clinical trials of HER2/neu-based peptide vaccination in human cancer patients have demonstrated that increased levels of HER2/neu-specific T-cells can be elicited after active immunization. Initiating cultures with greater numbers of antigen-specific T cells facilitates expansion. In addition, cytokines, such as interleukin-12, when added during ex vivo culturing along with interleukin-2 can selectively expand antigen-specific T-cells. Interleukin-12 also enhances antigen-specific functional measurements such as interferon-gamma and tumor necrosis factor-alpha release. Refinements in ex vivo expansion techniques may greatly improve the feasibility of tumor-antigen T-cell-based therapy for the treatment of advanced-stage HER2/neu-overexpressing breast malignancy.
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PMID:Expansion of HER2/neu-specific T cells ex vivo following immunization with a HER2/neu peptide-based vaccine. 1189 86

The bispecific antibody (BiAb) anti-CD3 x anti-Her2/neu (Her2Bi), combines Her2/neu targeting with nonmajor histocompatibility complex-restricted cytotoxicity mediated by activated T cells (ATCs). To evaluate this adaptive immunotherapeutic strategy for augmenting antitumor immune response toward hormone-refractory prostate cancer (HRPC), normal donor or patient T cells were activated with anti-CD3, expanded ex vivo in interleukin-2, and then armed with Her2Bi (5-500 ng per million ATCs). In vitro, arming ATCs with Her2Bi increased the percent specific cytotoxicity toward PC-3 prostate adenocarcinoma cells 2-3 fold and increased the secretion of Th1 cytokines granulocyte-macrophage colony-stimulating factor, tumor necrosis factor-alpha, and interferon-gamma when compared with unarmed ATCs or ATCs armed with an irrelevant BiAb. Her2Bi-armed ATCs administered with PC-3 (Winn Assay) or injected intratumorally prevented development or induced remissions, respectively, of PC-3 tumors in severe combined immunodeficient beige mice. Intravenously administered Her2Bi-armed ATCs localized to PC-3 xenografts mediated cytotoxicity toward tumor cells and produced significant tumor growth delay of PC-3 tumors, but not Her2/neu-negative LS174T colon adenocarcinoma xenografts. By flow cytometry analyses, Her2Bi-armed ATCs had a proliferative advantage over unarmed ATCs and persisted in the circulation and tumor tissues longer than unarmed ATCs. These findings suggest that Her2Bi-armed ATC therapy may be an effective, nontoxic, tumor-specific treatment for Her2-positive HRPC.
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PMID:Anti-CD3 x anti-HER2 bispecific antibody effectively redirects armed T cells to inhibit tumor development and growth in hormone-refractory prostate cancer-bearing severe combined immunodeficient beige mice. 1547 95

Dendritic cells (DCs) are powerful antigen-presenting cells that process antigens and present peptide epitopes in the context of the major histocompatibility complex molecules to generate immune responses. DCs are being studied as potential anticancer vaccines because of their ability to present antigens to naive T cells and to stimulate the expansion of antigen-specific T-cell populations. We investigated an antitumor vaccination using DCs modified by transfer of a nonsignaling neu oncogene, a homologue of human HER-2/neu, in a transgenic model of breast cancer. BALB-neuT mice develop breast cancers as a consequence of mammary gland-specific expression of an activated neu oncogene. We vaccinated BALB-neuT mice with bone marrow-derived DCs transduced with Ad.Neu, a recombinant adenovirus expressing a truncated neu oncoprotein. The vaccine stimulated the production of specific anti-neu antibodies, enhanced interferon-gamma expression by T cells, and prevented or delayed the onset of mammary carcinomas in the mice. Over 65% of vaccinated mice remained tumor free at 28 weeks of age, whereas all of the mice in the control groups developed tumors. When challenged with a neu-expressing breast cancer cell line, vaccinated tumor-free animals had delayed tumor growth compared with controls. The antitumor effect of the vaccine was specific for expression of neu. Studies showed that CD4+ T cells were required in order to generate antitumor immunity. Importantly, the effectiveness of the vaccine was not diminished by preexisting immunity to adenovirus, whereas the protection afforded by vaccination that used direct injection of Ad.Neu was markedly reduced in mice with anti-adenovirus antibody titers. DCs modified by recombinant adenoviruses expressing tumor-associated antigens may provide an effective antitumor vaccination strategy.
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PMID:Vaccination by genetically modified dendritic cells expressing a truncated neu oncogene prevents development of breast cancer in transgenic mice. 1552 Feb 11


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