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)

Tamoxifen causes an objective response in about one-third of metastatic breast cancer and in only half of the breast cancer patients with estrogen receptor (ER) positive tumors. Steroid-receptor coactivator-1 (SRC-1) appears to be a general coactivator for steroid receptors and rate limiting factor necessary for efficient ER transactivation. We aimed to evaluate whether SRC-1 expression is an additional factor for prediction of response to first-line tamoxifen therapy in patients who developed recurrent disease. Here for the first time, we report on SRC-1 expression using a semi-quantitative RT-PCR in 21 primary breast tumors, seven mammary tumor cell-lines, 12 fibroblast cultures, and six normal breast tissues. The highest levels of SRC-1 were observed in normal tissues, intermediate levels in tumor tissues, and the lowest levels in breast tumor cell-lines. There was no relationship between the levels of SRC-1 in these primary tumors and the proportion of tumor cells within the surgical samples, nor with ER status. The median SRC-1 level was, however, lower in tumors from patients that did not respond to tamoxifen. Our findings suggest that high levels of SRC-1 indicate a favorable response to tamoxifen of patients with recurrent breast cancer.
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PMID:Predictive value of SRC-1 for tamoxifen response of recurrent breast cancer. 954 Nov 93

Tamoxifen, an estrogen antagonist, is usually employed in the treatment of breast cancer. Its mechanism of action is not well known because an antiproliferative effect of the drug has been shown also in estrogen receptor negative tumors, most likely mediated by the inhibition of local growth factors and particularly IGF-I. However, the action of tamoxifen on the GH-IGF-I axis is still open to investigation. We have investigated the influence of acute and chronic treatment with tamoxifen on GH response to GHRH and IGF-I serum levels in six postmenopausal women with metastatic breast cancer. A GHRH test (50 microg i.v. at time 0, GH determinations at 0, 15, 30, 60, 90 and 120 min) was performed (a) basally, (b) 3 h after 40 mg oral administration of tamoxifen and (c) after 8 weeks of 20 mg twice a day oral tamoxifen treatment. IGF-I was measured basally and after chronic tamoxifen therapy. No significant modifications in GH response to GHRH were observed after acute or chronic treatment with tamoxifen vs the basal test. On the contrary, chronic tamoxifen treatment induced a significant decrease in serum IGF-I levels. Basal pretreatment levels of 123+/-18 microg/l were suppressed to 65+/-11 microg/l (mean suppression 47%, P < 0.001). These preliminary data confirm the inhibitory effect of tamoxifen on IGF-I production but seem to exclude the possibility that this effect may be due to an inhibition of GH secretion.
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PMID:Effect of acute and chronic administration of tamoxifen on GH response to GHRH and on IGF-I serum levels in women with breast cancer. 975 41

Recent trials comparing single-agent vs combination therapy in metastatic breast cancer suggest that it may be time to reconsider the belief that combination chemotherapy is the gold standard of treatment. Based on the limited randomized trial data available to date, high-dose chemotherapy with stem-cell rescue should not be viewed as "state-of-the art" treatment for metastatic disease and should be used only in the context of clinical trials. Recent trials have explored the optimal dosing and scheduling of the taxanes, as well as the possible role of these agents in combination regimens. Capecitabine (Xeloda), a new oral fluoropyrimidine, appears to be comparable in efficacy to CMF (cyclophosphamide, methotrexate, and fluorouracil), and preclinical data suggest possible synergy between this agent and the taxanes. Other promising agents under study include liposome-encapsulated doxorubicin (TLCD-99), an immunoconjugate linking a chimeric human/mouse monoclonal antibody to doxorubicin molecules; MTA (LY231514), a multitargeted antifolate; and marimistat, a broad-spectrum matrix metalloproteinase inhibitor. Tamoxifen (Nolvadex) remains the most important hormonal agent, but new antiestrogens and selective estrogen receptor modulators (SERMs) may provide alternatives. The potential role of new aromatase inhibitors as first-line hormonal agents requires further study. Finally, the possible synergy between trastuzumab (Herceptin), a recombinant humanized monoclonal antibody to the HER-2/neu protein, and paclitaxel (Taxol) is being studied in two clinical trials.
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PMID:Update on the management of advanced breast cancer. 1035 85

Two cases of metastatic breast cancer are reported in which endocrine chemotherapy with Toremifene + 5'-DFUR proved markedly effective. Case 1: A 69-year-old female. After CAF therapy as a adjuvant chemotherapy, Tamoxifen and Tegafur had been administered. At the 5th postoperative year, multiple metastases to lung and a rise in the tumor marker were found. Since the patient was not desirous of intensive chemotherapy, administration of Toremifene 120 mg/day and 5'-DFUR 800 mg/day was initiated. The patient showed PR 9 months after and achieved CR 14 months later. Case 2: A 48-year-old female. CAF therapy for a total of 6 cycles was performed as adjuvant chemotherapy. The patient was administered Tamoxifen and followed. On bone scintigrams 3.5 years after surgery, an abnormal accumulation appeared in the left sternoclavicular joint, and an infiltrative tumor mass was formed in the skin of that region. Administration of Toremifene + 5'-DFUR was initiated. After 6 months, the infiltrative mass disappeared. These findings are suggestive of the effectiveness of this combined chemotherapy.
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PMID:[Endocrine chemotherapy (high-dose toremifene + 5'-DFUR) found markedly effective for 2 cases of metastatic breast cancer]. 1039 29

Antioestrogen therapy is currently receiving renewed interest for several reasons. Tamoxifen was introduced in the treatment of metastatic breast cancer more than three decades ago. The drug significantly reduces long term mortality and also reduces the risk of contralateral tumours when administered in early breast cancer. Five years of tamoxifen is now standard in adjuvant endocrine therapy, and the drug is currently being evaluated for breast cancer prevention. Despite this, several aspects regarding the pharmacology of the drug are still unclear, and the scientific rationale for dose selection has recently been challenged. Several novel antioestrogen compounds, called selective oestrogen receptor modifiers (SERMs), express selective oestrogen agonistic or antagonistic properties depending on the organ or test system evaluated. Some of these drugs, like raloxifene, do not seem to promote the development of endometrial cancer, although they still have selected oestrogen-like beneficial effects. This paper reviews the pharmacologic and the pharmacokinetic aspects of the different SERMs with particular emphasis on their potential use in therapy and prevention of breast cancer.
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PMID:Selective oestrogen receptor modifiers (SERMs) and breast cancer therapy. 1081 62

Liarozole is an imidazole compound that inhibits enzymes involved in steroid hormone aromatisation and retinoid metabolism. The IDBBC branch of the EORTC has performed a series of phase II studies of the agent in four groups of postmenopausal women with metastatic breast cancer. This paper reports the results of the first two groups: 'Chemotherapy Resistant' (unrestricted ER status, 1 or 2 prior chemotherapy regimens, 0-2 prior hormonal therapies) and 'Potentially Hormone Sensitive' (ER positive or unknown, 1 or 2 prior hormonal therapies with a substantial disease free interval or progression free survival, and no history of chemotherapy for metastatic disease). Liarozole was administered at 150-300 mg orally bid. The objective response rate was 12% in the 'Chemotherapy Resistant' group (n = 34), and 22% in the 'Potentially Hormone Sensitive' group (n = 37), with median response durations of 9 and 14 months, respectively. Median time to treatment failure was only 2 months in both groups, due largely to the significant percentage (24%) of patients who ceased treatment following excessive mucocutaneous and gastrointestinal toxicity. This adverse event profile will limit its use in breast cancer. Results of the 'ER negative' and 'Tamoxifen Refractory' groups will be reported in a future paper.
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PMID:EORTC 10941: A phase II study of liarozole in postmenopausal patients with 'chemotherapy-resistant' or 'potentially hormone sensitive' metastatic breast cancer. 1084 81

The assessment of angiogenesis in breast cancer is of importance as a key indicator of survival and response to therapy. Circulating vascular endothelial growth factor (VEGF) measurements may provide a less subjective analysis than microvessel density (MVD) or immunohistochemical analysis of VEGF expression; however, most studies have used serum, which is now known to largely reflect platelet-derived VEGF concentrations. This study examined for the first time both plasma (VEGFp) and serum (VEGFs) VEGF concentrations in 201 blood samples from pre- and postmenopausal healthy controls and from patients with benign breast disease, localized breast cancer, breast cancer in remission, or metastatic breast cancer and related these to other clinicopathological markers. VEGFp but not VEGFs concentrations of patients with localized disease were significantly elevated compared with normal controls (P = 0.016). Patients with metastatic disease had higher VEGFp and VEGFs levels than normal controls (P < 0.001, P = 0.044 respectively), and higher VEGFp, but not VEGFs, than patients with benign disease (P = 0.009) and patients with localized disease (P = 0.004). However, the highest VEGFp and VEGFs concentrations were seen in patients in remission compared with normal controls (P < 0.001 and P = 0.008, respectively). VEGFp concentrations in patients in remission were also higher than in patients with benign disease (P = 0.01) or patients with localized disease (P = 0.005). Tamoxifen treatment was significantly associated with higher circulating and platelet-derived VEGF levels. Circulating VEGF did not correlate with any clinicopathological factor, including MVD or VEGF expression. VEGF expression was significantly correlated with estrogen receptor status and inversely correlated with tumor grade. MVD correlated with tumor size. Tamoxifen-induced increases in VEGF may be important in clinical prognosis or associated pathologies.
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PMID:Vascular endothelial growth factor (VEGF) in breast cancer: comparison of plasma, serum, and tissue VEGF and microvessel density and effects of tamoxifen. 1085 Apr 35

The authors report a rare case of cutaneous angiosarcoma arising more than 5 years after excision of a 1.5 cm invasive ductal cancer of the breast. All lymph nodes were negative for metastatic breast cancer in this 68-year-old female. The patient had postoperative therapy consisting of 5040 cGy over a 5 week period using a 6 Megavolt linear accelerator. After radiation therapy to the breast and axillae, the patient developed chronic hard, taut edema of the irradiated right breast. Tamoxifen was administered for 5 years and then stopped. Three months after the cessation of tamoxifen, cutaneous angiosarcoma was found by skin biopsy. A complete mastectomy removed all tumor with clear margins. There are less than 60 cases of radiation associated breast angiosarcoma found in the literature. The presence of chronic lymphedema in the breast after radiation therapy possibly contributes to the development and is an early warning sign for later development of secondary angiosarcoma. The characteristic purple nodules and discoloration of the irradiated skin is the hallmark to suspect the diagnosis. The authors recommend long-term clinical surveillance for this tumor for all patients who have received breast conservative surgical therapy with concomitant radiation therapy for primary breast cancer.
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PMID:Cutaneous angiosarcoma in an irradiated breast after breast conservation therapy for cancer: association with chronic breast lymphedema. 1127 29

The sex hormone estrogen is important for many physiologic processes. Prolonged stimulation of breast ductal epithelium by estrogen, however, can contribute to the development and progression of breast cancer, and treatments designed to block estrogen's effects are important options in the clinic. Tamoxifen and other similar drugs are effective in breast cancer prevention and treatment by inhibiting the proliferative effects of estrogen that are mediated through the estrogen receptor (ER). However, these drugs also have many estrogenic effects depending on the tissue and gene, and they are more appropriately called selective estrogen receptor modulators (SERMs). SERMs bind ER, alter receptor conformation, and facilitate binding of coregulatory proteins that activate or repress transcriptional activation of estrogen target genes. Theoretically, SERMs could be synthesized that would exhibit nearly complete agonist activity on the one hand or pure antiestrogenic activity on the other. Depending on their functional activities, SERMs could then be developed for a variety of clinical uses, including prevention and treatment of osteoporosis, treatment and prevention of estrogen-regulated malignancies, and even for hormone replacement therapy. Tamoxifen is effective in patients with ER-positive metastatic breast cancer and in the adjuvant setting. The promising role for tamoxifen in ductal carcinoma-in-situ or for breast cancer prevention is evolving, and its use can be considered in certain patient groups. Other SERMs are in development, with the goal of reducing toxicity and/or improving efficacy, and future agents have the potential of providing a new paradigm for maintaining the health of women.
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PMID:Selective estrogen receptor modulators: structure, function, and clinical use. 1096 46

Breast cancer is a common problem in older women. As the number of medical illnesses increases with age and the life expectancy decreases, the benefits of systemic therapy for women with breast cancer become questionable. All women over age 65 years are at high enough risk of breast cancer to consider the risk/benefit ratio of preventive therapy with tamoxifen (Nolvadex) or participation in the Study of Tamoxifen and Raloxifene (STAR) trial. Adjuvant chemotherapy and hormonal therapies for early breast cancer significantly improve disease-free and overall survival; recommendations for their use are based on risk of tumor recurrence. Use of tamoxifen in the adjuvant setting in women with receptor-positive tumors is a relatively simple decision in light of its favorable toxicity profile. The delivery of adjuvant chemotherapy is a more complicated decision, and the patient's wishes, estimated life expectancy, presence of comorbid conditions, and estimated benefit from treatment should be considered. The primary goal of the treatment of metastatic breast cancer is palliation. We discuss trials specific to older women and make appropriate treatment recommendations. Unfortunately, there is a paucity of data from clinical trials in women over age 70 years. However, because the clinical trial is the primary scientific mechanism for testing the efficacy of a treatment, every effort should be made to enter older women into treatment protocols.
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PMID:Systemic therapy for older women with breast cancer. 1130 28


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