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)

Despite the rational use of hormonal, surgical, radiotherapeutic, and chemotherapeutic interventions, metastatic breast cancer represents a historically incurable disease and is currently one of the leading causes of cancer-related death in women. Survival rates in patients with metastatic breast cancer vary with location and type of metastasis, but virtually all will relapse. Standard cytotoxic therapies for the treatment of metastatic breast cancer remain unsatisfactory; thus, new active agents can be a valuable option for many patients. Topotecan (Hycamtin; SmithKline Beecham Pharmaceuticals, Philadelphia, PA), a topoisomerase I inhibitor, currently is being assessed in the treatment of metastatic breast cancer. Preliminary results from preclinical and phase I trials suggest topotecan is active against breast cancer. Results of ongoing phase II trials thus far suggest that topotecan may be effective in stabilizing disease and prolonging time to relapse. Further studies are needed to determine whether topotecan will prove to be a valuable new option in the treatment of metastatic breast cancer.
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PMID:The potential role of topotecan in the treatment of advanced breast cancer. 942 61

The topoisomerase inhibitors, camptothecin and etoposide target the activity of topoisomerase I and II respectively. These agents, or their analogues, are undergoing clinical trials for the treatment of metastatic breast cancer. In this study, we examined the response of eight breast epithelial cell lines, including six lines derived from breast cancers and two immortalized normal epithelial lines to camptothecin and etoposide. The lines varied by 700 fold in their sensitivity to the growth inhibiting effects of camptothecin and 30 fold in their response to etoposide. The BT474 line was the most resistant to both agents. The other cell lines did not have uniform sensitivity to both drugs, i.e., some lines were sensitive to one drug but relatively resistant to the other. A variety of parameters in these lines were analyzed to elucidate mechanisms of resistance including S phase, doubling time, expression and activity of topoisomerase I and II, expression of mdr-1, p53 status, cell cycle arrest, level of apoptosis, and expression of the apoptotic proteins Bcl-2 and Bax. We found that low levels of the topo I protein and its enzymatic activity were associated with increased resistance to camptothecin. This was not true for topo II activity and etoposide. Increased apoptotic responses were generally observed in cell lines that were sensitive to etoposide and this correlated with low ratios of Bcl-2/Bax protein. No single parameter was entirely predictive of response. However, the BT474 line displayed a series of characteristics including slow growth, the presence of mutant p53, low topo I activity, and a high Bcl-2/Bax ratio which together likely contributed to the resistance of this line to both etoposide and camptothecin.
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PMID:Complex response of breast epithelial cell lines to topoisomerase inhibitors. 971 86

Chemotherapy plays an important role in the management of metastatic breast cancer. The anthracyclines (doxorubicin, epirubicin) and the taxanes (paclitaxel, docetaxel) are considered the most active agents for patients with advanced breast cancer. Traditionally, the anthracyclines have been used in combination with cyclophosphamide and 5-fluorouracil (FAC, FEC). The taxanes have single-agent activity similar to older combination chemotherapy treatments. There is great interest in developing anthracycline/taxane combinations. Capecitabine is indicated for patients who progress after anthracycline and taxane therapy. Vinorelbine and gemcitabine have activity in patients with metastatic breast cancer and are commonly used as third- and fourth-line palliative therapy. The role of high-dose chemotherapy is not well-defined and remains experimental. Novel cytotoxic therapy strategies include the development of anthracycline, taxane, and oral fluoropyrimidine analogues; antifolates; topoisomerase I inhibitors, and multidrug resistance inhibitors. A better understanding of the biology of breast cancer is providing novel treatment approaches. Oncogenes and tumor-supressor genes are emerging as important targets for therapy. Trastuzumab, a monoclonal antibody directed against the Her-2/neu protein, has been shown to prolong survival in patients with metastatic breast cancer. Other novel biologic therapies interfere with signal transduction pathways and angiogenesis. The challenge for the next decade will be to integrate these promising agents in the management of metastatic and primary breast cancer.
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PMID:Chemotherapy of metastatic breast cancer: what to expect in 2001 and beyond. 1130 25

Cytotoxic chemotherapy is important for treatment of patients with hormone-insensitive advanced breast cancer. A variety of new cytotoxic agents are promising alone or in combination. The originality, the clinical activity and side effects, as well as the current development status of these agents are reviewed. These agents include the new antimicrotubules (analogues of taxanes and vinorelbine; epothilone derivatives), oral formulations of 5-fluorouracil and other antimetabolites (tomudex, alimta, gemcitabine), liposomal anthracyclines, platinum analogues, topoisomerase I inhibitors and other compounds such as ET-743. Finally, new molecular-targeted therapies of potential interest in the treatment of metastatic breast cancer are reviewed. The growing availability of such biological therapies given alone and mainly in combination with hormonal and chemotherapeutic agents may improve in the near future the outcome of patients with metastatic breast cancer.
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PMID:New cytotoxic agents and molecular-targeted therapies in the treatment of metastatic breast cancer. 1263 7

For women who develop hormone-refractory metastatic breast cancer, or who have breast cancers that are not estrogen-dependent (hormone receptor-negative), treatment with chemotherapy is the best option. Mitomycin (Mutamycin) and irinotecan (CPT-11, Camptosar) have marginal activity in breast cancer. However, the sequential administration of mitomycin and irinotecan appears to have synergism in preclinical studies, as mitomycin upregulates the level of topoisomerase I, the target of irinotecan. A phase I clinical trial of pharmacologically based sequential administration of mitomycin on day 1 followed by irinotecan on days 2 and 8 was performed in previously treated solid tumor patients. In five heavily pretreated women with breast cancer, one patient had a complete response, one patient had a partial response, and one patient had stable disease. Upregulation of topoisomerase I gene expression in peripheral blood mononuclear cells was observed in two of the responding patients. A phase II trial of mitomycin followed by irinotecan in women with previously treated metastatic, inflammatory, or locally advanced breast cancer is currently ongoing.
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PMID:Rationale for mitomycin and irinotecan use in advanced breast cancer. 1280 Jun 2

An international meeting on 'New Drugs in Cancer Therapy' was held at the National Tumor Institute of Naples, on 17-18 June 2004. The first session of the meeting focused on analogs of conventional anti-cancer drugs, such as taxanes, platinum compounds, anthracyclines and topoisomerase I inhibitors. The data of a phase II trial of BMS-247550, an epothilone B analog, in patients with renal cell carcinoma were reported. Data were also presented on BBR-3464, a trinucleate platinum analog which was developed on the grounds of greater potency, a more rapid rate of DNA binding and the ability to induce apoptosis regardless of the p53 status of the cell. Pegylated-coated liposomal formulation doxorubicin (Caelyx) has shown efficacy in metastatic breast cancer and in advanced ovarian cancer; sabarubicin is a third-generation anthracycline with equal or superior potency to doxorubicin or idarubicin in a variety of human tumor cell lines of different histotypes. The main mechanisms of resistance to topoisomerase I inhibitors were discussed; data on diflomotecan were reported, showing a narrow therapeutic index of the drug. The second session of the meeting focused on the ErbB family as a target for anti-cancer therapy. Recent evidence of a correlation between epidermal growth factor receptor (EGFR) mutations at exons 18-21 and clinical response of advanced non-small cell lung cancer to gefitinib therapy was commented on. The issue of the association between ErbB2 expression and gefitinib activity was addressed, while clinical data of a phase II study of gefitinib in advanced breast cancer were presented. Monoclonal antibodies targeting EGFR represent another worthwhile way to interfere with EGFR-driven signal transduction. Cetuximab is reaching market registration in advanced colorectal cancer; in particular, due to the results of the BOND study. The recently presented results of the Bonner study strongly support the activity of this drug in head and neck cancer. A step forward in the research on anti-EGFR monoclonal antibodies may be represented by humanized monoclonal antibodies, such as EMD 72000 and ABX-EGF. Imatinib mesylate is probably the most outstanding example of an effective targeted therapy--its activity in gastrointestinal stromal tumors was so exciting that the drug reached the market without undergoing phase III evaluation. The third session of the meeting was on angiogenesis inhibitors. Drugs may interfere with the angiogenic process via different mechanisms and there is a sound rationale for combining anti-angiogenic agents with chemotherapy or multiple anti-angiogenic strategies. Clinical results obtained with direct anti-angiogenic agents have been negative up to now, but some exciting results have been seen with bevacizumab, a monoclonal antibody targeting vascular endothelial growth factor (VEGF). A few VEGF-tyrosine kinase inhibiting small molecules, such as ZD6474, AZD2171 and PTK/ZK, are undergoing clinical trials. The fourth session of the meeting was on interference with intracellular signal transduction. Farnesyl transferase inhibitors exert their action by interfering with either pro-Ras or RhoB farnesylation. Several clinical studies of different phases with compounds belonging to this class have been carried out, either alone or in combination with chemotherapy; unfortunately, all of them have turned out to be negative. Cell cycle inhibitors, such as CYC-202 and BMS-387032, represent a class of interesting compounds which are in the early phase of development and whose clinical results are eagerly awaited. Another strategy to achieve cell cycle inhibition is to target heat shock protein 90, a molecular chaperone required for protein folding. Clinical data on depsipeptide, a histone deacetylase (HDAC) inhibitor with activity in T cell lymphoma, were presented. Suberoylanilide hydroxamic acid is another small molecular weight inhibitor of HDAC activity. Phase I/II clinical trials have shown low toxicity and evidence of anti-tumor activity; on the other hand, this compound has potential for synergism with radiotherapy, chemotherapy and biologicals.
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PMID:New drugs in cancer therapy, National Tumor Institute, Naples, 17-18 June 2004. 1565 20

Metastasis to multiple organs is the primary cause of mortality in breast cancer patients. The poor prognosis for patients with metastatic breast cancer and toxic side effects of currently available treatments necessitate the development of effective tumor-selective therapies. Neural stem cells (NSCs) possess inherent tumor tropic properties that enable them to overcome many obstacles of drug delivery that limit effective chemotherapy strategies for breast cancer. We report that increased NSC tropism to breast tumor cell lines is strongly correlated with the invasiveness of cancer cells. Interleukin 6 (IL-6) was identified as a major cytokine mediating NSC tropism to invasive breast cancer cells. We show for the first time in a preclinical mouse model of metastatic human breast cancer that NSCs preferentially target tumor metastases in multiple organs, including liver, lung, lymph nodes, and femur, versus the primary intramammary fat pad tumor. For proof-of-concept of stem cell-mediated breast cancer therapy, NSCs were genetically modified to secrete rabbit carboxylesterase (rCE), an enzyme that activates the CPT-11 prodrug to SN-38, a potent topoisomerase I inhibitor, to effect tumor-localized chemotherapy. In vitro data demonstrate that exposure of breast cancer cells to conditioned media from rCE-secreting NSCs (NSC.rCE) increased their sensitivity to CPT-11 by 200-fold. In vivo, treatment of tumor-bearing mice with NSC.rCE cells in combination with CPT-11 resulted in reduction of metastatic tumor burden in lung and lymph nodes. These data suggest that NSC-mediated enzyme/prodrug therapy may be more effective and less toxic than currently available chemotherapy strategies for breast cancer metastases.
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PMID:Human neural stem cell tropism to metastatic breast cancer. 2208 33

Anthracyclines and taxanes are cytotoxic agents that are commonly used for the treatment of breast cancer, including in the adjuvant, neoadjuvant, and metastatic setting. Each drug class of is associated with cumulative and potentially irreversible toxicity, including cardiomyopathy (anthracyclines) and neuropathy (taxanes). This may either limit the duration of therapy for advanced disease, or prevent retreatment for recurrence if previously used as component of adjuvant or neoadjuvant therapy. Several classes of cytotoxic agents have been evaluated in patients with anthracycline and taxane-pretreated metastatic breast cancer (MBC), including other antitubulins (vinorelbine, ixabepilone, eribulin), antimetabolites (capecitabine, gemcitabine), topoisomerase I inhibitors (irinotecan), platinum analogues (cisplatin, carboplatin), and liposomal doxorubicin preparations. No trials have shown an overall survival advantage for combination chemotherapy in this setting, indicating that single cytotoxic agents should usually be used, expect perhaps in patients with rapidly progressive disease and/or high tumor burden.
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PMID:Chemotherapy in Patients with Anthracycline- and Taxane-Pretreated Metastatic Breast Cancer: An Overview. 2344 80