Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although hypercalcemia is a well-known complication of malignant diseases, hypocalcemia seems to be a rather rare one. A 34-yr-old woman with advanced breast cancer who presented hypocalcemia is described. She had generalized multiple osteolytic bone metastases which were progressive in spite of chemo-endocrine and radiation therapy. She was admitted because of severe bone pain and dyspnea caused by bilateral pleural effusion. Laboratory examination on admission showed that the serum calcium was 9.6 mg/dl, serum total protein 5.9 g/dl, serum inorganic phosphorus 4.6 mg/dl, and serum alkaline phosphatase 29.6 King-Armstrong units. The serum calcium gradually fell to 7.0 mg/dl on the 45th hospital day when the serum total protein was 6.8 g/dl and she complained of paresthesia in the extremities. On the 58th day, severe tachycardia and hypotension developed and she died of congestive heart failure on the 67th hospital day. At that time the serum calcium was 5.4 mg/dl. During her hospital course, the plasma parathyroid hormone levels were examined repeatedly and were 0.4, 0.6, 0.6 and 0.7 ng/ml (normal; less than 0.5 ng/ml). Autopsy revealed that cancer invaded the space between the thyroid and the trachea and no parathyroid glands could be found even in the mediastinum. Microscopically the parathyroid glands were replaced completely by the cancer cells. These observations indicate that metastasis of breast cancer to the parathyroid glands caused relative hypoparathyroidism, resulting in hypocalcemia. In addition, congestive heart failure which was refractory to digitalis and diuretics might have been caused by impaired contractility of the myocardium associated with hypocalcemia.
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PMID:A case of advanced breast cancer associated with hypocalcemia. 688 61

Malignant and benign human breast tissue containing radiographic evidence of calcifications were studied by means of scanning electron microscopy and x-ray microanalysis. In addition to the well-known calcium-phosphorus deposits, discrete particles containing calcium with little or no phosphorus and calcium in combination with other elements were found. Moreover, particles containing elements other than calcium were observed. These include Al, Fe, Mg, Si, Cu, Zn, Cr, Ti, Ni, Pb, Au, Ag, Mo, Cl, I. Some of these "noncalcifications" contained a single element, others a combination of elements. These findings differ from the view that all breast particles are calcifications. Further study could lead to the development of new diagnostic techniques for the detection of breast cancer and/or chemotherapeutic agents.
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PMID:Non-calcified breast particles: a possible new marker of breast cancer. 707 44

The basis for the use of nuclear magnetic resonance (NMR) spectroscopy as a tool to study the metabolism of breast cancer cells is described. The differences between proton (1H), carbon (13C), and phosphorus (31P) NMR methods is explained, and the techniques of cell extracts, cell suspensions and perfusion methods for cells are detailed. In order to perfuse cells they are preferably trapped in a gel matrix, either in the form of a thread or a bead. The gel must have appropriate properties that enables efficient oxygenation and availability of nutrients and drugs. The metabolic effects of perfusion of breast cancer cells with nutrients, drugs, and hormones are reported, and the clinical relevance of these results and methods are outlined.
Breast Cancer Res Treat 1994
PMID:Metabolism of breast cancer cells as revealed by non-invasive magnetic resonance spectroscopy studies. 788 Nov 6

Because of their high affinity for bone, bisphosphonates are used both in the treatment of benign and malignant bone disease and in radiopharmaceutical bone imaging. A prospective study was undertaken to evaluate whether intravenous clodronate (dichloromethylene bisphosphonate) therapy might affect the results of bone scintigraphy with 99mTc-labeled methylene diphosphonate (MDP). In 11 female patients with breast cancer and metastatic bone disease, quantitative bone scans were obtained using a region of interest (ROI) method on Days 0 and 22. After intravenous clodronate therapy from Day 1 to Day 21, all metastatic bone lesions were still detectable, and median ROI ratios did not differ to a statistically significant extent from baseline values. Serum calcium levels decreased (p = 0.0449), whereas parathyroid hormone concentrations showed an increase (p = 0.0053). Mean serum levels of creatinine, inorganic phosphorus, osteocalcin, gamma glutaminyl-transpeptidase and alkaline phosphatase remained unchanged. However, a more than twofold rise in the serum activity of alkaline phosphatase was measured in three patients. We conclude that 3 wk of intravenous clodronate treatment did not impair the sensitivity of 99mTc-MDP bone scintigraphy in detecting bone lesions in patients with metastatic breast cancer.
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PMID:Effect of clodronate treatment on bone scintigraphy in metastatic breast cancer. 866 85

Oestrogen levels play a major role in conditioning the rates of bone changes in women. Tamoxifen is a synthetic oestrogen antagonist commonly used as an adjuvant therapy for breast cancer. The goal of the present study was to study the amount and the elemental composition of bone minerals in the appedicular skeleton of women with breast cancer treated with adjuvant tamoxifen, as well as to investigate the possibility of increased risk for osteoporosis. Forty-two patients, aged 41-65 years, without skeletal metastases were studied. The mean duration of tamoxifen administration on a daily dose of 20 mg was 21 months (range 1-59 months). It was found that neither the amount of phosphorus in hands (HBP) nor forearm bone mineral content (BMC) differ statistically from those of age-matched healthy subjects. This was confirmed by reassessing bone mineral status after 30 months in 17 postmenopausal patients treated with tamoxifen for a mean time of 52 months. In conclusion, our data support that long-term tamoxifen treatment has no adverse or protective effect on the amount and elemental composition of the appedicular skeleton.
Breast Cancer Res Treat 1996
PMID:Elemental composition of bone minerals in women with breast cancer treated with adjuvant tamoxifen. 875 May 83

The present study investigated the effect of dehydroepiandrosterone (DHEA) on bone mass and serum lipids in the rat with dimethylbenz(a)anthracene (DMBA)-induced mammary carcinoma. The animals received DHEA once daily, percutaneously, at the dose of 5, 10, or 20 mg for 9 months following a single dose of 20 mg DMBA at 50-52 days of age. Bone mineral content (BMC) and bone mineral density (BMD) of total skeleton, lumbar spine, and femur were measured by dual energy x-ray absorptiometry. A 9-month treatment with DHEA increased BMC and BMD of total skeleton by 14.2% to 14.5% (all P < 0.01) and 6.7% to 8.3% (all P < 0.01), respectively. Similarly, femoral BMC and BMD were stimulated by 13.6% to 14.7% (all P < 0.05) and by 8.1% to 9.5% (all P < 0.01), respectively. In addition, BMD of lumbar spine was increased by 10.4% to 10.8% (all P < 0.05), whereas the 9.4% to 11.1% increment in BMC of lumbar spine was not statistically significant. Treatment with DHEA led to 26% (NS), 60% (P < 0.01), and 62% (P < 0.01) decreases in serum triglyceride levels at the same doses. On the other hand, no significant change in serum cholesterol concentrations was observed. Two hundred and seventy-nine days after DMBA administration, the incidence of mammary carcinoma had decreased from 95% in control animals to 73% (P < 0.05), 57% (P < 0.01), and 38% (P < 0.01) at the daily percutaneous doses of 5, 10, and 20 mg of DHEA, respectively. Moreover, the mean tumor number per tumor-bearing animal and the mean tumor area per tumor-bearing animal were also reduced by the same treatments. DHEA increased serum total alkaline phosphatase activity and decreased urinary calcium excretion, but had no effect on the urinary ratio of hydroxyproline to creatinine and urinary phosphorus excretion. These data show that DHEA exerts a stimulatory effect on bone mass and an inhibitory effect on serum triglycerides, as well as a preventive effect on the development of mammary carcinoma induced by DMBA in the rat. Such data suggest that while decreasing the risk of breast cancer, DHEA replacement therapy could also exert beneficial effects on the bone and lipid metabolism in women receiving DHEA replacement therapy.
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PMID:Effect of dehydroepiandrosterone on bone mass, serum lipids, and dimethylbenz(a)anthracene-induced mammary carcinoma in the rat. 923 92

Although treatment with dehydroepiandrosterone (DHEA) and the antiestrogen EM-800 alone decreased dimethylbenz(A)anthracene (DMBA)-induced mammary tumor incidence from 95% to 57% and 38%, respectively, approximately 9 months after DMBA administration, only two tumors developed in the group of animals that received the combination of DHEA and EM-800, and these two tumors disappeared before the end of the experiment (P < 0.01 vs. DHEA or EM-800 alone). Average tumor number per tumor-bearing animal as well as average tumor area per tumor-bearing animal were further decreased in animals that received the combination therapy compared with the effect of each treatment alone (P < 0.01). DHEA induced 6.9% (P < 0.01), 10.6% (P < 0.05), and 8.2% (P < 0.01) increases in bone mineral density of total skeleton, lumbar spine, and femur, respectively. The addition of EM-800 to DHEA did not affect the enhancing effect of DHEA on bone mass. The combination of the two drugs had important inhibitory effects on the urinary excretion of calcium and phosphorus as well as on the urinary hydroxyproline/creatinine ratio. Serum total alkaline phosphatase was stimulated by DHEA. Treatment with EM-800 decreased both serum triglyceride and cholesterol levels, whereas DHEA had an inhibitory effect on serum triglycerides. Although treatment with EM-800 caused a marked atrophy of the mammary gland, DHEA alone reduced lobular hyperplasia seen in aged intact rats while causing an androgen-specific stimulation of the same structures in animals already receiving the antiestrogen EM-800. The combination of DHEA and EM-800 lowered ovarian weight by 24% (P < 0.01) and decreased serum estradiol concentrations to intact control levels, whereas each compound alone had no effect on ovarian weight and stimulated serum estradiol levels by 45% (P < 0.05) and 46% (P < 0.05), respectively. Treatment with EM-800 caused a marked inhibition of uterine and vaginal weight. The present data show the additive inhibitory effects of DHEA and EM-800 on the development of DMBA-induced mammary carcinoma in the rat, thus suggesting the potential benefits of such a combination for the prevention of breast cancer in women while preserving or even increasing bone mass and maintaining a favorable lipid profile.
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PMID:Combined effects of dehydroepiandrosterone and EM-800 on bone mass, serum lipids, and the development of dimethylbenz(A)anthracene-induced mammary carcinoma in the rat. 932 61

As interest in the properties of xenoestrogenic compounds has grown, different in vitro cell culture systems have been proposed as models, against which to gauge relative estrogenic impact. Previous research indicated that some organochlorine-based pesticides elevated the production of 16 alpha-hydroxyestrone relative to 2-hydroxyestrone in ER+ MCF-7 breast cancer cells while phytochemicals like indole-3-carbinol reduced this ratio. That this ratio may be a biological marker of the risk of breast cancer has recently been demonstrated. In this study we have carried out the same paradigm in two ER- cell lines to examine the effect of receptor status. To determine whether the impact of chlorinated pesticides can be modulated by phytochemicals, the ability of indole-3-carbinol or brassinin to reverse the changes in metabolism was examined. Non-persisting phosphorus-based pesticides were also studied and shown not to have an effect on estrogen metabolism. The implications of these findings are examined.
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PMID:Role of the estrogen receptor in the action of organochlorine pesticides on estrogen metabolism in human breast cancer cell lines. 949 44

The effect of EM-800, a new non-steroidal antiestrogen having pure antiestrogenic activity, was studied on chemical carcinogenesis induced by dimethylbenz(a)anthracene (DMBA) as well as on serum lipids and bone mass in the rat. Treatment with EM-800 orally, once daily, for 282 days (9 months), starting 3 days before DMBA administration, decreased the incidence of tumors from 95% in control animals to 60% (p < 0.01), 38% (p < 0.01), and 28% (p < 0.01) at the daily doses of 25 microg, 75 microg, and 250 microg, respectively. The average number of tumors per animal decreased from 4.5 +/- 0.5 tumors in the control group to 0.9 +/- 0.2 (p < 0.01), 0.5 +/-0.2 (p < 0.01), and 0.3 +/- 0.1 (p < 0.01) tumors in the rats treated with the above-indicated doses of the anti-estrogen. In addition, treatment with the increasing doses of EM-800 reduced serum cholesterol levels to 64%, 56%, and 48% of control, while serum triglycerides decreased to 31%, 28%, and 30% of control. Bone mineral content (BMC) and bone mineral density (BMD) of total skeleton, femur, and lumbar spine were not significantly affected following 282 days of treatment with EM-800. However, treatment with EM-800 inhibited the urinary ratio of hydroxyproline to creatinine (HP/Cr) from 14.0 +/- 3.90 micromol/mmol in controls to 7.6 +/-0.8 (p < 0.05), 6.8 +/- 0.8 (p < 0.01), and 6.8 +/- 1.1 (p < 0.01) micromol/mmol, respectively, while the same treatment had no effect on serum total alkaline phosphatase (tALP) activity or urinary calcium and phosphorus excretion. The 25 microg, 75 microg, and 250 microg daily doses of EM-800 inhibited uterine weight by 35% (p < 0.01), 62% (p < 0.01), and 66% (p < 0.01), while vaginal weight was reduced by 8% (p < 0.05), 30% (p < 0.01), and 38% (p < 0.01), respectively. In agreement with the 27% increment (p < 0.05) in ovarian weight at the highest anti-estrogen dose used, serum androstenedione (p < 0.05), androst-5-ene-3beta,17beta-diol (p < 0.01), testosterone (p < 0.05), and estradiol (p < 0.01) levels were increased. The present data show that EM-800 prevents the development of DMBA-induced mammary tumors while simultaneously inhibiting uterine and vaginal weight, reducing serum cholesterol and triglyceride levels, and having no adverse effect on bone mass following 9 months of treatment in the rat.
Breast Cancer Res Treat 1998 May
PMID:Prevention of development of dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in the rat by the new nonsteroidal antiestrogen EM-800 (SCH57050). 969 6

The urinary concentrations of 16 estrogens and 11 polyamines were quantitatively determined by gas chromatography-mass spectrometry and gas chromatography with nitrogen-phosphorus detection. Samples from patients with stages I-IV of breast cancer (35 cases, aged 27-65 years) as well as from age-matched normal female subjects (25 cases, aged 22-61 years) were tested. Also, the ratios of precursor to product metabolite including 16alpha-OH E1 to 2-OH E1, which are linked to estrogen and polyamine biosynthetic pathways, were determined to explore enzyme involvement in breast cancer and to evaluate the potential usefulness of these ratios and concentrations as disease staging markers. It was confirmed that major estrogens and 16a-OH E1 were positively associated with breast cancer and catechol estrogens including 2-OH E1 were inversely associated with breast cancer. The ratios of N1-acSp/Spd and 16alpha-OH E1/2-OH E1 might be a useful dual marker for staging of breast cancer. From the variation of the relative ratios of polyamines, it is suggested that alteration in polyamine oxidase (PAO) activity may play an important role in the development of breast cancer.
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PMID:Estrogens and polyamines in breast cancer: their profiles and values in disease staging. 992 59


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