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)

The HER2 protein is encoded by the HER2/neu gene and it is homologous to the epidermal growth factor receptor. Overexpression of HER2, usually in association with gene amplification, occurs in approximately 25-30% of breast cancers. There are currently several different methods available to evaluate HER2 status, e.g. immunohistochemical (IHC), and fluorescence in situ hybridization (FISH) assays. The HER2 protein is a viable therapeutic target. The humanized anti-HER2 monoclonal antibody trastuzumab (Herceptin) has demonstrated activity in clinical trials in women with metastatic breast cancer overexpressing HER2. The mechanisms of the action of this antibody involve disruption of DNA repair and induction of antibody-dependent cellular cytotoxicity. Response rates to the antibody given as a single agents in the treatment of HER2 overexpressing metastatic breast cancer have ranged from 12 to 27%. Patients who received trastuzumab in combination with chemotherapy had a significantly longer time to progression, higher overall survival compared with patients who had received chemotherapy alone. In the treatment of women with HER2 overexpressing tumors an overall response rate of 57% for combination trastuzumab plus paclitaxel compared with 25% for paclitaxel alone was found. Trastuzumab has an important role in the treatment of HER2 overexpressing metastatic breast cancer. Its place in adjuvant treatment has not been proved up to now. The optimal use of trastuzumab in the treatment of HER2 positive advanced breast cancer is under active investigation. Due to the high rate of clinical activity and low incidence of severe toxicity trastuzumab is a very promising drug in the treatment of breast cancer. The author's purpose was to summarize the results of the trials using trastuzumab treatment, and discuss the methods used to determine the HER2 status.
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PMID:[Human recombinant anti-HER2 monoclonal antibody--a new targeted treatment in breast cancer]. 1177 Jan 75

Overexpression of the HER2/neu oncogene (also known as c-erbB2) is a frequent molecular event in multiple human cancers, including breast and ovarian cancer. Patients with cancer that overexpress HER2/neu are associated with unfavorable prognosis, shorter relapse time, and low survival rate. Treatments that target HER2/neu expression in cancer cells have been shown to be useful strategies to significantly reverse the malignancy induced by HER2/neu overexpression. The humanized anti-HER2/neu antibody, trastuzumab (Herceptin; Genentech, Inc, South San Francisco, CA) has proven to be effective in clinical trials in patients with metastatic breast cancer. In addition, tyrosine kinase inhibitors such as emodin can also target the HER2/neu oncogenic activity. Emodin treatment inhibits HER2/neu tyrosine kinase activity and preferentially suppresses the transformation of HER2/neu-overexpressing breast cancer cells. Emodin also sensitizes HER2/neu-overexpressing cancer cells to chemotherapeutic agents, including cisplatin, doxorubicin, etoposide, and paclitaxel. Alternatively, HER2/neu overexpression can be repressed by attenuating the promoter activity of the HER2/neu gene. We have identified a number of potent transcriptional regulators, including the ets family member PEA3 and the adenovirus type 5 E1A, which are able to repress HER2/neu gene expression. Expression of these transcriptional regulators resulted in downregulation of HER2/neu promoter activity and reversed the transformed phenotype of the cancer cells in vitro. In vivo studies show that these HER2/neu repressors can act therapeutically as tumor suppressor genes for tumors that overexpress HER2/neu. These preclinical studies clearly indicate that transcriptional repressors that downregulate HER2/neu can be effective regimens for cancer treatment in a gene therapy format. More importantly, the tumor-free survival rate of treated animals is dramatically increased under nontoxic doses compared with untreated animals. A phase I clinical trial using E1A-liposome in breast and ovarian patients has recently been completed. Following treatment, we observed downregulation of the HER2/neu protein accompanied by E1A expression in both cancer and noncancer cells. Numbers of tumor cells in the pleural effusion or ascites were found to be dramatically reduced after treatment. Furthermore, apoptosis was strongly induced in the tumor cells. A phase II study has been started to further evaluate therapeutic efficacy and tumor suppression mechanisms of E1A. These studies show the clinical potential of targeting HER2/neu in cancer therapy.
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PMID:Targeting HER2: recent developments and future directions for breast cancer patients. 1177 2

HER2/neu amplification/overexpression confers more aggressive and malignant characteristics on breast cancer cells. Patients with HER2/neu-amplified breast cancer have a worse prognosis than those with normal HER2/neu expression. Over the past decade, the intracellular signaling pathways associated with this growth factor receptor have been elucidated. Multiple therapeutic strategies that target the HER2/neu oncoprotein are under development. Trastuzumab (Herceptin; Genentech, Inc, South San Francisco, CA), a humanized monoclonal antibody that binds to the extracellular domain of the HER2/neu receptor, has undergone phase I, II, and III clinical trials. These studies have shown that, as a single agent, trastuzumab has substantial and reproducible antitumor activity in HER2/neu-amplified metastatic breast cancer. In addition, when added to chemotherapy, trastuzumab improves antitumor efficacy as measured by time to progression, response rate, and survival. Additional chemotherapy/trastuzumab combinations are under active evaluation, and new schedules of administration are being tested. Thus, trastuzumab is the first successful example of molecularly targeted therapy in the management of metastatic breast cancer.
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PMID:Overview of treatment results with trastuzumab (Herceptin) in metastatic breast cancer. 1177 5

Landmark clinical studies of new drugs developed to target specific forms of cancer were reported in 2001. Herceptin, a monoclonal antibody against the Her2/neu receptor tyrosine kinase, prolonged the survival of women with Her-2/neu positive metastatic breast cancer, when combined with chemotherapy. STI-571, a small molecule inhibitor of the Bcr-Abl, c-kit and platelet derived growth factor receptor tyrosine kinases, produced dramatic clinical responses in patients with Bcr-Abl positive chronic myeloid leukemia and c-kit positive gastrointestinal stromal tumors. These examples have galvanized the cancer research community to extend kinase-inhibitor therapy to other cancers.
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PMID:Rational therapeutic intervention in cancer: kinases as drug targets. 1179 May 64

We report on the prognostic significance of tumorbiologic parameters and CD34(+) cell dose in 120 patients with metastatic breast cancer (MBC) who received high-dose chemotherapy (HDCT) with autologous blood stem cell transplantation as first-line treatment. Her2/neu, p53, Ki67, and bcl-2 protein expression were studied using immunohistochemical staining on formalin-fixed, paraffin-embedded primary tumor sections. DNA content of tumor cells (DNA-index) and tumor cell proliferation (S-phase fraction) were measured by DNA flow cytometry. The relationship between these parameters and the CD34(+) cell dose and progression free (PFS) and overall survival (OS) was analyzed. With a median follow-up period of 40 months (range, 7-89 months), no more than two metastatic sites (relative risk [RR] = 3.84 [95% confidence interval (CI) 1.49-10]; p =.005) and hyperploidy (RR = 2.58 [95% CI 1.26-5.26]; p =.009) were independent predictors of longer PFS according to multivariate analysis. Independent prognostic factors of longer OS included one or two metastatic sites (RR = 4.16 [95% CI 1.96-4.16]; p <.001), a positive combined hormone receptor status (RR = 2.45 [95% CI 1.45-4.14]; p =.001) and a high number of infused stem cells (>7.8 x 10(6) CD34(+) cells per kg body weight) (RR = 2.0 [95% CI 1.17-3.42]; p =.01). In conclusion, positive hormone receptors, < or =2 metastatic sites, high DNA-index and high CD34(+) cell dose (>7.8 x 10(6) CD34(+) cells per kg) are predictors for a favorable outcome after autotransplantation for MBC. Our observation might indicate a favorable effect of HDCT in MBC patients with overexpression of Her2/neu who might have a worse prognosis when treated with conventional chemotherapy.
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PMID:Stem cell dose and tumorbiologic parameters as prognostic markers for patients with metastatic breast cancer undergoing high-dose chemotherapy with autologous blood stem cell support. 1179 20

Despite intensive treatment efforts, the prognosis for lung cancer is very poor; less than 15% of patients survive 5 years. Trastuzumab, a monoclonal antibody targeting the HER2/neu protein receptor, is effective in the treatment of metastatic breast cancer and may be useful in the treatment of non-small cell lung cancer (NSCLC). Using the HercepTest (Dako; Carpenteria, CA), 25% of NSCLC show 2+ or greater HER2/neu expression, but only 6% to 8% of NSCLC tumors have 3+ overexpression. Positive HER2/neu expression is most often seen in adenocarcinomas compared with squamous cell carcinomas or large cell carcinomas, and is rarely seen in small cell lung cancer. As determined by fluorescence in situ hybridization analysis, the high degree of HER2/neu gene expression and gene amplification seen in breast cancer is lower in NSCLC. Polysomy is the cause of increased HER2/neu expression in most NSCLC. Prospective clinical studies with trastuzumab in lung cancer are ongoing. Future studies in NSCLC need to include immunohistochemistry and fluorescence in situ hybridization analysis to determine the method of choice for evaluating clinically relevant HER2/neu-positive tumors.
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PMID:HER2/neu expression in malignant lung tumors. 1189 14

The taxanes paclitaxel and docetaxel have an important role in the treatment of breast cancer, and numerous randomized trials have evaluated their efficacy for this indication. A systematic, evidence-based review was performed, which included all randomized, controlled trials evaluating taxanes for the treatment of early-or advanced-stage breast cancer that were identified in CANCERLIT and MEDLINE searches. The primary objectives of this review were to determine the dose and schedule for each taxane that was associated with the most favorable therapeutic index, and to determine whether (and under what circumstances) the taxanes improved survival. The search revealed 18 randomized phase II (n = 1) or phase III (n = 17) trials. For metastatic breast cancer, the dose and schedule associated with the most favorable therapeutic index for paclitaxel was 175 mg/m2 given as a 3-hour infusion every 3 weeks, and docetaxel was 60-100 mg/m2 given as a 1-hour infusion every 3 weeks. Survival was improved under the following circumstances: (1) when 4 cycles of paclitaxel (175 mg/m2 every 3 weeks) was given following 4 cycles of conventional doxorubicin-cyclophosphamide for axillary node-positive operable breast cancer, (2) when trastuzumab was added to paclitaxel as first-line therapy for metastatic breast cancer that overexpressed HER2/neu, and (3) when docetaxel was given as second-line therapy for anthracycline-resistant disease. Although a survival benefit was found for taxanes as a component of first-line therapy in two of six trials, the interpretation of both positive trials was confounded by a lack of crossover to taxane therapy in those who were initially randomized to receive standard therapy. The taxanes improve survival in patients with early-stage breast cancer and selected patients with metastatic breast cancer. Further research is necessary in order to identify the efficacy of docetaxel relative to paclitaxel, the optimal dose of docetaxel, the role of weekly taxane therapy, the role of trastuzumab plus taxanes in early-stage disease, and whether taxanes are more effective when given concomitantly or sequentially in patients with early-stage disease.
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PMID:Taxanes for breast cancer: an evidence-based review of randomized phase II and phase III trials. 1189 88

Interest in platinum compounds for the treatment of breast cancer has been reawakened because of preclinical studies indicating synergy of platinum salts with the monoclonal antibody trastuzumab in human breast cancer cell lines that overexpress HER2/neu. Cisplatin, carboplatin, and iproplatin are not very active as single agents in patients with previously treated metastatic breast cancer (MBC). The activity of oxaliplatin has not been adequately tested in refractory MBC. On the other hand, cisplatin is very active as first-line chemotherapy, with response rates (RR) of 50%; carboplatin appears to be moderately active in patients without prior chemotherapy (RR around 30%). The clinical effectiveness of the other platinum compounds (iproplatin, oxaliplatin, and others) has not yet been fully tested as first-line chemotherapy. Platinum compounds have been extensively tested in combination with other antitumoral agents. Cisplatin combinations have been employed as neoadjuvant chemotherapy in women with locally advanced breast cancer. These combinations are very active, although the precise contribution of cisplatin to the overall activity is not known. Combinations with cisplatin have been investigated, essentially, as salvage therapy for patients with previously treated MBC. The combinations of cisplatin with older pharmacological agents (5-fluorouracil, etoposide) have moderate activity, while the combinations of cisplatin with the newer agents (vinorelbine, paclitaxel, docetaxel, gemcitabine) appear to be more active. The combinations of carboplatin with the classical agents (5-fluorouracil, etoposide) are poorly active in previously treated MBC; however, the combination of carboplatin with the taxanes (docetaxel, paclitaxel) is more active. Of greatest interest is the synergy between the platinum derivatives and the monoclonal antibody trastuzumab demonstrated in vitro in breast cancer cell lines overexpressing HER2/neu. Currently, several combinations of platinum compounds (either cisplatin or carboplatin) with docetaxel and trastuzumab are under clinical testing in patients with MBC who overexpress HER2/neu. The preliminary results are very promising, and these combinations will soon be tested in the adjuvant setting. Cisplatin, carboplatin, and perhaps, oxaliplatin appear to have some antitumor activity in MBC and can be combined safely with other agents that are active in this disease. However, the precise role that platinum compounds play in the treatment of breast cancer remains to be defined.
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PMID:Platinum compounds in the treatment of advanced breast cancer. 1189 13

One of the current trends in breast cancer research is to identify markers that can predict response to specific anticancer therapies; intense laboratory research and therapeutic trials are exploiting this strategy. The combination of cytotoxic drugs directed at the tumor population with the highest probability of being sensitive to them with molecules targeted at intracellular signaling and cell cycle control pathways, which may be deregulated as part of the malignant process, represents our best hope for improved survival in both early and advanced disease. The transmembrane tyrosine kinase receptor, HER2/neu, has been the subject of much investigation with respect to its prognostic value, predictive value, and as a target of antibody-mediated therapy. Retrospective evidence strongly suggests that HER2 overexpression is associated with decreased disease-free and overall survival in node-positive, and possibly also node-negative, breast cancer. Prospective trials have demonstrated that antibodies to HER2 can produce tumor responses in women with advanced disease that overexpresses this molecule. Moreover, the combination of such antibodies with cytotoxic drugs has been one of the few recent strategies to improve survival duration in metastatic breast cancer. The evidence supporting the role of HER2 as a factor predictive of response to hormone therapy and cytotoxic drugs is more ambiguous and requires prospective assessment. The available literature is reviewed herein, with a focus on the predictive value of HER2, potential mechanisms of resistance and sensitivity to various drugs, and future research directions involving this important molecule.
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PMID:HER2/neu as a predictive factor in breast cancer. 1189 84

Although only less than 10% of women with primary breast cancer have clinicopathologic signs of overt metastases, metastatic relapse occurs in about half of the cases with apparently localized tumors within five years after surgery. In 23% of the patients, bone marrow metastases are detectable at first relapse and this rate even increases in patients with metastatic breast cancer. However, hematogeneous or lymphatic spread of occult tumor cells can arise before diagnosis at an early stage of primary tumor growth and is regularly underestimated by currently available clinical and pathologic staging procedures. We studied cytokeratin-positive (CK+) cells in the bone marrow (BM) and tumor markers in the blood of 128 patients with primary breast cancer in order to obtain an early diagnosis of residual disease. In a second study, we monitored cytokeratin (CK)/17-1A positive cells in the BM and peripheral blood stem cells (PBSC) to evaluate whether dose intensive or high-dose (HD)-chemotherapy can eliminate micrometastases in high-risk breast cancer patients. The overall CK+ rate was 34% (44/128 patients), 29% (15/51) for patients with T1 tumors, 33% (28/84) for N0 patients and 31% (26/82) for patients with G1-2 breast carcinoma. Interestingly, 67% of CK+ patients were only positive in one of the two BM aspirates studied. At least one tumor marker including carcinoembryonic antigen, carbohydrate antigen 15-3 and tissue polypeptide antigen, was increased in 58/128 (45%) patients [21/58 (36%) were CK+ in the BM]. Surprisingly, levels for the extracellular domain of Her-2/neu in serum samples were within the normal range in every patient studied. After a 2-year follow-up, 7/128 patients relapsed (3/7 CK+/TM-; 2/7 CK-/TM+; 2/7 CK-/TM-). We concluded that studying two BM aspirates for CK+ cells by immunocytochemistry in combination with tumor marker determination is useful for identifying patients with a higher risk for relapse. A tumor cell enrichment technique, applied in 70 patients prior to immunocytochemistry using dynabeads directly coupled to an antibody (BerEp4) targeting the 17-1A antigen, did not enhance the detection rate of disseminated tumor cells in this patient group. We monitored CK+/17-1A+ cells in the BM and PBSC and studied Her-2/neu serum levels of patients with locally advanced (n=13, group 1) and metastatic breast cancer (n=30, group 2). CK+ cells were found in the BM of 3/13 (23%) group 1 patients before but not after chemotherapy resulting in an overall survival (OS) of 92% after a median follow-up of 33 months. Contamination of PBSC in 2/9 (22%) patients was not associated with decreased survival. In group 2 patients, the CK+ rate was 60% (18/30 patients) before and 40% (4/10 patients) after therapy with an OS rate of 43% after 29 months. PBSC samples were positive in 7/24 (29%) patients. CK+ BM and PBSC led to a rapid progress and short OS whereas tumor cell free BM and PBSC resulted in a mean OS of 30 months. The antigen 17-1A was detected on most CK+ cells in both patient groups before therapy, on all CK+ PBSC and on CK+ cells in group 2 patients after therapy. Increased Her-2/neu levels were found in group 2 patients before chemotherapy. In conclusion, micrometastatic cells are present in blood and PBSC grafts of high-risk breast cancer patients and can survive even HD-chemotherapy. Immunotherapeutic target antigens on the cell surface of these cells support the idea that a combined chemoimmunotherapy might be successful in eliminating minimal residual disease.
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PMID:A summary of two clinical studies on tumor cell dissemination in primary and metastatic breast cancer: methods, prognostic significance and implication for alternative treatment protocols (Review). 1195


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