Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0278488 (metastatic breast cancer)
 7,812 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

One of the leading causes of death for women is metastatic breast cancer. Because most animal tumors do not accurately model clinical metastatic disease, the development of effective therapies has progressed slowly. In this study, we establish the poorly immunogenic mouse 4T1 mammary carcinoma as a postsurgical animal model. 4T1 growth characteristics parallel highly invasive human metastatic mammary carcinoma and, at the time of surgery, the extent of disease is comparable with human stage IV breast cancer. Progress in understanding the immune response has led to innovative immune-based anticancer therapies. Here, we test in this postsurgical model, a novel cell-based vaccine, combining MHC class II, CD80(B7.1), and SEB superantigen. Effective treatment of tumor-bearing mice with this immunotherapy requires expression of all three molecules. Mean survival time is extended from 5-7.5 weeks for control-treated mice to 6-10.5 weeks for therapy-treated mice. Increased survival is accompanied by a maximum of 100-fold decrease in clonogenic lung metastases. These therapeutic effects are particularly noteworthy because: (a) the postoperative model demonstrates that early metastases responsible for morbidity are established by 2 weeks after tumor inoculation with 7 x 10(3) parental 4T1 cells into the mammary gland; (b) the immunotherapy is started 4 weeks after tumor inoculation when the mice contain extensive, pre-established, disseminated metastases; and (c) CD4+ and CD8+ T cells are required for the effect.
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PMID:Cooperativity of Staphylococcal aureus enterotoxin B superantigen, major histocompatibility complex class II, and CD80 for immunotherapy of advanced spontaneous metastases in a clinically relevant postoperative mouse breast cancer model. 1082 45

Thirty HLA-A2 women with metastatic breast cancer received up to 14 vaccinations with MDA-MB-231-CD80, an HLA-A2 allogeneic breast cancer cell line, which had been lipofected with the cDNA for the CD80 costimulatory molecule. Tumor cells were administered with BCG or GM-CSF as an adjuvant. Sera obtained before and after vaccination were analyzed for antibodies to tumor cell lysate, MUC1, HER2/neu and p53. Since the cell line was grown in fetal bovine serum (FBS), sera were also analyzed for antibodies to FBS. Eighteen of 24 patients for whom sera were available exhibited anti-FBS activity at baseline. Eleven of these 18 patients and all six patients without baseline anti-FBS activity showed an increased titer after vaccination. The anti-FBS activity required that serum samples be absorbed in excess FBS to detect specific antibodies to tumor cell lysate. A two-fold increase in the titer of IgG specific to tumor cell lysate was observed in 6 patients. Eight of 24 patients made an antibody response to HER-2/neu, four of 24 to MUC1 and one of 24 to p53. Although antibody production to a variety of tumor cell-associated antigens was detected our results suggest that a whole cell vaccine comprising a CD80-transfected allogeneic breast cancer cell line with adjuvant BCG or GM-CSF was not a reliable method to induce significant antibody responses in women with advanced breast cancer.
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PMID:Identification of tumor-specific antibodies in patients with breast cancer vaccinated with gene-modified allogeneic tumor cells. 1261 8

Cancer vaccines are currently a major focus of immunotherapy research. The combination of specific targeting and low levels of toxicity makes vaccination an attractive approach. There are a variety of immunogens that can be employed to vaccinate patients in order to induce or enhance an antitumor response. The observation that most T-cell priming occurs via presentation of tumor antigens from tumor cells engulfed by host antigen-presenting cells, rather than by direct presentation by vaccine tumor cells themselves, provides the immunological rationale for an allogeneic tumor cell vaccine approach. Furthermore, there are practical advantages over an autologous tumor cell vaccine approach. We summarize herein the limited experience using allogeneic whole cell vaccines in patients with breast cancer. We also describe in vitro immunological results using peripheral blood mononuclear cells from women with stage IV breast cancer who were enrolled in a phase I trial employing a human leukocyte antigen-A2-matched, CD80-modified, allogeneic, whole cell vaccine. Clinical trials employing allogeneic tumor cell vaccines have achieved encouraging immunological and clinical effects in stage IV patients. Allogeneic tumor cell vaccines are safe, feasible, and associated with low toxicity, and the early clinical results suggest that they are worthy of further study
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PMID:Allogeneic breast cancer cell vaccines. 1262 Jan 56

A number of genetic alterations are required for malignant transformation. However, these mutations provide the source for tumor-associated antigens which can be recognized by cellular effectors of the immune system. Recent advances in tumor immunology - such as the improved understanding of antigen presentation as well as T cell activation - have opened new perspectives for cancer immunotherapy. The advantage of using tumor cell based vaccines is that these comprise the complete antigen pool of an individual tumor for activating polyclonal immune responses. However, the induction of antigen-specific immune responses is impaired by the fact that T cell activation is depending on additional nonspecific costimulatory signals provided by the antigen-presenting cell. The majority of solid human tumors does not express costimulatory molecules and is unable to deliver all signals required for T cell activation. In contrast, tumors often induce immunologic tolerance. Therefore, the introduction of genes encoding costimulatory molecules such as CD80 or cytokines is aimed at conferring the immunostimulatory potential of tumor cells. We have undertaken efforts at endowing a breast carcinoma cell line expressing at least seven known tumor associated antigens with immunostimulatory competence by CD80 gene transfer. In preclinical studies this cell line was demonstrated to induce specific immune responses. We designed a phase I/II trial to administer the CD80-modified cell line to patients with metastatic breast cancer to determine the toxicities of the vaccination protocol and nature of the vaccine-induced immune response.
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PMID:[CD80-modified tumor cell lines: implications for cell-based vaccinations in breast cancer patients]. 1282 70

MDA-MB-231, an HLA-A2(+), HER2/neu(+) allogeneic breast cancer cell line genetically modified to express the costimulatory molecule CD80 (B7-1), was used to vaccinate 30 women with previously treated stage IV breast cancer. Expression of CD80 conferred the ability to deliver a costimulatory signal and thereby improved the antigen presentation capability of the tumor cells to patient T cells in vitro. Patients were vaccinated with 10(7) or 10(8) irradiated gene-modified tumor cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) or BCG, three times at 2-week intervals and then monthly until progressive disease developed. GM-CSF-related flulike symptoms and minor injection site reactions were observed frequently. Prolonged disease stabilization was observed in four patients but no objective tumor regressions were seen. Immune responses were measured in matched peripheral blood samples collected before and after treatment from 9 of 15 patients treated at the 10(8) tumor cell dose. Four patients exhibited MHC class I-restricted cytokine production in response to the parental breast cancer cell line. One patient maintained an increased number of circulating tumor-specific, interferon gamma-secreting CD8(+) T cells for 24 months after the last vaccination. One patient exhibited a tumor-specific interleukin 5 response to an autologous tumor cell line. This immunization strategy proved to be safe and feasible, and induced tumor-specific immune responses in a minority of patients; however, no objective tumor regressions were observed.
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PMID:Vaccination of women with metastatic breast cancer, using a costimulatory gene (CD80)-modified, HLA-A2-matched, allogeneic, breast cancer cell line: clinical and immunological results. 1288 50

Adjuvant treatment is still only working in a small percentage of breast cancer patients. Therefore, new strategies need to be developed. Immunotherapies are a very promising approach because they could successfully attack tumor cells in the stage of dormancy. To assess the feasibility of using an allogeneic approach for vaccination of breast cancer patients, we selected a CD80-transfected breast cancer cell line based on its immunogenic properties. Using CD80+ KS breast cancer cells and human leukocyte antigen (HLA)-A*02-matched peripheral blood mononuclear cells (PBMCs) of breast cancer patients in allogeneic mixed lymphocyte-tumor cell cultures (MLTCs), it was possible to isolate HLA-A*02-restricted cytotoxic T cells (CTLs). Furthermore, a genetically modified KS variant expressing influenza A matrix protein serving as a surrogate tumor-associated antigen (TAA) was able to stimulate flu peptide-specific T cells alongside the induction of alloresponses in MLTCs. KS breast cancer cells were demonstrated to express already known TAAs such as CEA, MUC-1, MAGE-1, MAGE-2, and MAGE-3. To further improve antigenicity, HER-2/neu was added to this panel as a marker antigen known to elicit HLA-A*02-restricted CTLs in patients with breast cancer. Thus, the antigen-processing and antigen-presentation capacity of KS cells was further demonstrated by the stimulation of HER-2/neu-specific CD8+ T cells in PBMCs of breast cancer patients in vitro. These results gave a good rationale for a phase I/II trial, where the CD80+ HER-2/neu-overexpressing KS variant is actually used as a cellular vaccine in patients with metastatic breast cancer. As a proof of principle, we present data from two patients where a significant increase of interferon-gamma (IFN-gamma) release was detected when postvaccination PBMCs were stimulated by allogeneic vaccine cells as well as by HLA-A*02-restricted HER-2/neu epitopes. In whole cell vaccine trials, monitoring is particularly challenging because of strong alloresponses and limited knowledge of TAAs. In this study, a panel of HER-2/neu epitopes, together with the quantitative real time (qRT)-PCR method to analyze vaccine-induced cytokines secreted by T cells, proved to be highly sensitive and feasible to perform an "immunological staging" following vaccination.
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PMID:A CD80-transfected human breast cancer cell variant induces HER-2/neu-specific T cells in HLA-A*02-matched situations in vitro as well as in vivo. 1536 76

Myeloid-derived suppressor cells (MDSCs) are highly immunosuppressive myeloid cells, which increase in cancer patients. The molecular mechanism behind their generation and function is unclear. Whereas granulocytic-MDSCs correlate with poor overall survival in breast cancer, the presence and relevance of monocytic-MDSCs (Mo-MDSCs) is unknown. Here we report for the first time an enrichment of functional blood Mo-MDSCs in breast cancer patients before they acquire a typical Mo-MDSC surface phenotype. A clear population of Mo-MDSCs with the typical cell surface phenotype (CD14(+)HLA-DR(low/-)CD86(low/-)CD80(low/-)CD163(low/-)) increased significantly first during disease progression and correlated to metastasis to lymph nodes and visceral organs. Furthermore, monocytes, comprising the Mo-MDSC population, from patients with metastatic breast cancer resemble the reprogrammed immunosuppressive monocytes in patients with severe infections, both by their surface and functional phenotype but also at their molecular gene expression profile. Our data suggest that monitoring the Mo-MDSC levels in breast cancer patients may represent a novel and simple biomarker for assessing disease progression.
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PMID:Systemic Monocytic-MDSCs Are Generated from Monocytes and Correlate with Disease Progression in Breast Cancer Patients. 2599 11

The advent of immune checkpoint blockade as a new strategy for immunotherapy has changed the outlook for many aggressive cancers. Although complete tumor eradication is attainable in some cases, durable clinical responses are observed only in a small fraction of patients, underlining urgent need for improvement. We previously showed that RON, a receptor tyrosine kinase expressed in macrophages, suppresses antitumor immune responses, and facilitates progression and metastasis of breast cancer. Here, we investigated the molecular changes that occur downstream of RON activation in macrophages, and whether inhibition of RON can cooperate with checkpoint immunotherapy to eradicate tumors. Activation of RON by its ligand, MSP, altered the gene expression profile of macrophages drastically and upregulated surface levels of CD80 and PD-L1, ligands for T-cell checkpoint receptors CTLA-4 and PD-1. Genetic deletion or pharmacological inhibition of RON in combination with anti-CTLA-4, but not with anti-PD-1, resulted in improved clinical responses against orthotopically transplanted tumors compared to single-agent treatment groups, resulting in complete tumor eradication in 46% of the animals. Positive responses to therapy were associated with higher levels of T-cell activation markers and tumor-infiltrating lymphocytes. Importantly, co-inhibition of RON and anti-CTLA-4 was also effective in clearing metastatic breast cancer cells in lungs, resulting in clinical responses in nearly 60% of the mice. These findings suggest that RON inhibition can be a novel approach to potentiate responses to checkpoint immunotherapy in breast cancer.
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PMID:Inhibition of RON kinase potentiates anti-CTLA-4 immunotherapy to shrink breast tumors and prevent metastatic outgrowth. 3022 50