Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153690 (bone metastases)
 6,382 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although urinary measurements of collagen degradation provide valid estimates of bone resorption, their clinical application is hampered by pronounced analytical and biological variability. Therefore, immunoassays for the determination of such parameters in serum have been developed. In this study, we assessed the performance of three new serum markers of bone turnover, i.e., C-terminal and N-terminal telopeptides of type I collagen (S-CTX and S-NTX) and bone sialoprotein. Results were compared with urinary total pyridinoline, total deoxypyridinoline, and urinary C-terminal telopeptides of type I collagen (U-CTX) and urinary N-terminal telopeptides of type I collagen (U-NTX). The study population included healthy men (n = 27), premenopausal (n = 30) and postmenopausal (n = 31) women, patients with hepatic dysfunction (HF, n = 24), renal failure (RF, n = 30), breast cancer without (BC-, n = 24) and with (BC+, n = 30) bone metastases, primary vertebral osteoporosis (OPO, n = 27), primary hyperparathyroidism (PHPT, n = 16), active Paget's disease of bone (n = 18), multiple myeloma (MM, n = 18), and patients with hypercalcemia of malignancy before and after treatment with pamidronate (HOM, n = 28). Changes in urinary and serum markers were similar in most metabolic bone diseases. However, differentiation between healthy controls and OPO, or PHPT, was improved by the serum markers. In MM, all serum and urinary markers were elevated (p < 0. 05 vs. controls). In BC+, skeletal involvement was reflected by significant increments in all indices (p < 0.01 vs. BC-), except U-CTX and S-CTX. In HOM, pamidronate-induced changes in biomarkers were most pronounced for U-CTX and S-CTX and S-NTX. HF and RF were associated with elevated levels of all serum markers (p < 0.05 vs. controls). In conclusion, measurements in serum reflect bone resorption to the same extent as the urinary indices. Since serum markers circumvent some of the limitations of urinary measurements, their use potentially improves the assessment of skeletal disorders.
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PMID:Novel serum markers of bone resorption: clinical assessment and comparison with established urinary indices. 1032 May 28

Breast cancer commonly metastasizes to bones, producing both osteolytic and osteoblastic deposits. Different markers for quantitative determination of bone turnover have been developed to evaluate bone metastases of breast cancer. The urinary deoxypyridinoline (Dpd), a crosslink product of collagen molecules found in bone and excreted in urine during bone degradation, and bone specific alkaline phosphatase (B-ALP), an isoenzyme localized in the membrane of osteoblasts and released in circulation during bone formation, were recently described as a group of markers of bone turnover in metastatic cancer. The urinary Dpd/creatinine (Cre) ratios and the serum B-ALP activity were determined in the samples from 148 patients who suffered from breast cancer (BC patients) with or without bone metastases, and 42 healthy women. For comparison, other biochemical markers, e.g. carcinoembryonic antigen (CEA), CA15-3, tissue polypeptide antigen (TPA), tissue polypeptide specific antigen (TPSA), and total alkaline phosphatase (T-ALP) in these samples were also evaluated. The results showed that there was a significant difference in urinary Dpd/Cre ratio between the control group and the patients with breast cancer (BC group) (mean +/- S.D., 5.69 +/- 1.26 vs. 8.19 +/- 3.95 nM/mM, P < 0.05). However, there was no significant difference between their B-ALP activities in the two groups. In addition, the BC patients with bone metastases showed elevated urinary Dpd/Cre ratios and B-ALP activities and ratios of (Dpd/Cre)/B-ALP in compare with BC patients without bone metastases (P < 0.05). Meanwhile, the urinary Dpd/Cre ratios (10.50 +/- 5.04 nmol/mmol) in the advanced stage of BC patients were higher than those in an early stage (7.45 +/- 3.23 nmol/mmol) (P < 0.05), but their serum B-ALP activities increased only in stage IV (P < 0.05). The urinary Dpd/Cre ratios also increased progressively according to the degree of bone metastases (P < 0.05), but their serum B-ALP activities only increased in severe bone metastases (P < 0.05). The results showed that the increase of a bone osteolytic activity took place earlier than that of a bone osteoblastic activity in the metastatic BC patients. In compare with other conventional markers, the best diagnostic efficiency of biochemical markers, analyzed by step wise discriminate analysis, was provided by CEA followed by Dpd/Cre ratio, CA15-3, TPA, TPSA, B-ALP and T-ALP. We conclude that showed the urinary Dpd/Cre ratio was a useful tumor marker to evaluate breast cancer with bone metastases.
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PMID:Biochemical markers for assessment of bone metastases in patients with breast cancer. 1051 61

The assay for the cross-linked carboxyterminal telopeptide of type I collagen (ICTP) has been shown to reflect increased type I collagen degradation in such pathological conditions as bone metastases and rheumatoid arthritis, but to be rather insensitive to the changes in physiological bone collagen turnover (e.g., induced by estrogen or bisphosphonate treatment). To determine the reasons for this discrepancy we localized the antigenic determinant recognized by the ICTP assay and studied the effects of two major osteoclastic proteinases, cathepsin K (EC 3.4.22.38) and matrix metalloproteinase-9 (MMP-9; gelatinase B; EC 3.4.24.35), on immunoreactivity. The antigenic determinant was shown to reside within the hydrophobic phenylalanine-rich regions of the carboxyterminal telopeptides of the two alpha1 chains of human type I collagen, situated between the triple helical domain and the lysine-derived trivalent cross-link. This conclusion was based on differences between the amino acid sequences and cross reactivities of the corresponding human and bovine antigens before and after proteolytic treatments with chymotrypsin. A trivalent cross-link is necessary for providing such a structure, because the divalently cross-linked and monomeric natural and synthetic peptides from the same region, but containing only one phenylalanine-rich sequence, showed poor immunoreaction. Recombinant human cathepsin K cleaved the trivalently cross-linked ICTP structure at two sites between the phenylalanine-rich region and the cross-link, destroying the reactivity with ICTP antibodies. On the contrary, the treatment of isolated ICTP by the matrix metalloproteinases MMP-9 (gelatinase B), MMP-1 (collagenase 1), or MMP-13 (collagenase 3) had no effect on the immunoreaction. Our results indicate that the increased circulating concentrations of ICTP found in several clinical situations are most likely produced by matrix metalloproteinases, whereas cathepsin K-mediated, osteoclastic bone resorption destroys ICTP antigenicity.
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PMID:Immunochemical characterization of assay for carboxyterminal telopeptide of human type I collagen: loss of antigenicity by treatment with cathepsin K. 1071 80

MECHANISMS OF BONE LOSS: In patients with bone metastases, bone loss is the consequence of a dissociated process combining excessive bone resorption and inhibited bone formation. This destructive process occurs in response to soluble factors secreted by metastatic cells (PTH-rP, cytokines) which activate osteoclasts. These cells also secrete proteases (cathepsin K, metalloprotease MMP-9) which degrade the bone's collagen network. Excessive bone resorption is also favored by direct interaction between the metastatic cells and stromal cells in the bone marrow in response to the activation of membrane receptors (integrins a4 beta 1 and a4 beta 7). Finally, metastatic cells secrete non-identified soluble factors capable of inhibiting osteoblast proliferation in vitro. EFFECT OF BONE LOSS ON THE METASTASIS: Bone is a major reservoir of growth factors (mainly TGF beta and IGF-1). Positive feedback mechanism operates at the site of osteolysis where TGF beta released by bone tissue induces a paracrine stimulation of PTH-rP production by metastatic cells. IGF-1 released by the bone favors grow of metastatic cells present in the marrow. In addition, IGF-1 as well as collagen proteolytic fragments may stimulate recruitment of new metastatic cells at the site of the bone metastasis. This creates a vicious circle of mutual stimulation between bone destruction and tumor proliferation.
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PMID:[Bone hyperresorption in bone metastases]. 1074 42

The report discusses a study of pyridinoline (Pyd) and deoxypyridinoline (Dpyd) as biochemical markers of bone resorption as well as total bone alkaline phosphatase level (APh) and that of its bone fraction as criteria of osteogenesis in skeletal lesions in breast, prostate and lung cancer and multiple myeloma. The investigation established a significantly enhanced Pyd and Dpyd excretion with urine and increased blood-serum APh levels in skeletal cancers (n = 271) as compared with healthy subjects (n = 173) and patients without bone metastases (n = 94). A case has been made for determination of total excretion of Pyd crosslinks of collagen to diagnose bone metastases. Most pronounced hyperenzymemia was found in prostate cancer which points to the leading role of APh as a bone metastasis marker. Pyd and Dpyd excretion and APh levels were significantly higher among patients multiple metastases with than in those with single bone metastases. The universality of pyridinoline crosslinks as skeletal damage markers has been confirmed by establishing a significant correlation between drug and therapeutic effect for Pyd and Dpyd only, in patients receiving ibandronate.
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PMID:[The biochemical markers of bone remodeling in cancer patients with skeletal involvement]. 1097 74

Hypogonadism is associated with osteoporosis in men. GnRH- agonist-induced hypogonadism increases bone turnover and bone loss in men, but the mechanism underlying these changes is unknown. To determine whether gonadal steroid deprivation increases the skeletal sensitivity to PTH or blunts the ability of PTH to promote 1,25-dihydroxyvitamin D formation, we infused human PTH-(1-34) at a dose of 0.55 U/kg.h for 24 h, in 11 men (ages, 50-82 yr) with locally advanced, node-positive, or biochemically recurrent prostate cancer but no evidence of bone metastases. PTH infusions were performed before initiation of GnRH agonist therapy (leuprolide acetate, 22.5 mg im, every 3 months) and again after 6 months of confirmed GnRH agonist-induced hypogonadism. Serum osteocalcin (OC), bone- specific alkaline phosphatase (BSAP), N-telopeptide (NTX), whole-blood ionized calcium, and 1,25-dihydroxyvitamin D were measured at baseline and every 6 h during each PTH infusion. Urinary NTX and free deoxypyridinoline (DPD) were assessed on spot morning samples before PTH infusion and on 24-h samples collected during the PTH infusions. Sex steroid levels were lowered to the castrate range in all subjects. Baseline serum NTX levels (drawn before PTH infusion) increased from 9.1 +/- 3.7 before leuprolide therapy to 13.9 +/- 5.0 nmol bone collagen equivalents (BCE)/L after leuprolide therapy (P = 0.003). Spot urine NTX collected before PTH infusion increased from 28 +/- 8 before leuprolide therapy to 49 +/- 17 nmol BCE/mmol creatinine after leuprolide therapy (P < 0.001), and urinary DPD increased from 4.7 +/- 1.1 to 7.4 +/- 1.8 nmol BCE/mmol creatinine (P < 0.001). Baseline serum OC and BSAP levels drawn before each PTH infusion did not change before vs. after leuprolide therapy. Serum NTX levels increased significantly during PTH infusion pre-GnRH agonist therapy (P < 0.001), and the rate of increase was greater after 6 months of GnRH agonist-induced hypogonadism (P < 0.01 for the difference in rates of change before and after GnRH agonist administration). Serum OC and BSAP levels decreased during PTH infusion (P < 0.001 for OC and P = 0.002 for BSAP), but the rates of decrease did not differ before or after leuprolide therapy (P = 0.45 for OC and P: = 0.19 for BSAP). Whole-blood ionized calcium levels increased during PTH infusion (P < 0.001), and the rate of increase was greater after GnRH agonist-induced hypogonadism (P = 0.068). Serum 1,25-dihydroxyvitamin D levels increased in response to PTH infusion before leuprolide therapy (P = 0.022), but there was no difference in the rate of increase before or after leuprolide therapy (P = 0.66). The incremental increase in urinary NTX excretion, but not DPD, during PTH infusion was greater after 6 months of leuprolide therapy (P = 0.029 for NTX, P = 0.578 for DPD). We conclude that suppression of sex steroids in elderly men increases the skeletal responsiveness to the bone resorbing effects of PTH infusion but does not affect the response of bone formation markers or 1,25-dihydroxyvitamin D to PTH. Changes in skeletal sensitivity to PTH may play an important role in the pathogenesis of hypogonadal bone loss in men.
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PMID:Effects of gonadal steroid suppression on skeletal sensitivity to parathyroid hormone in men. 1115 1

Bone metastases and the strong interaction between osseous and metastatic cell populations require interdisciplinary thought and actions. If it were possible to interrupt the malignant dialogue between tumour and bone at an early stage, this might not only reduce the amount of bone destruction, but could also reduce the incidence of osseous metastases and remove the source of secondary metastases to other organs. Studies into the preventive effects of bisphosphonates are currently running or are planned. Most of these studies are in breast cancer patients with involvement of the axillary lymph nodes. The prognostic factors of lymph node status, tumour size and grading are better than none, but do not select patients at a high risk of skeletal metastasis. This would be much better done by using immunohistochemical methods to investigate the primary tumour for bone sialoprotein and parathyroid hormone-related protein (PTHrP). However, these methods are complicated, have not been validated in large numbers of patients and are not standardized. Serum tests for bone sialoprotein, PTHrP and collagen fragments are currently still under development and cannot be recommended generally. The clinical importance of tumour cells in the bone marrow has been demonstrated but is still only used at a few centres.
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PMID:Prognostic factors for skeletal relapse in breast cancer. 1141 65

Pseudosclerodermatous panniculitis is an unusual variant of panniculitis that results as a complication of megavoltage radiotherapy. Four women developed this unusual entity on the anterior chest and abdominal skin after receiving megavoltage therapy for either breast carcinoma or painful bone metastases from breast carcinoma. Histopathologically, the epidermis and dermis of the involved area showed little or no evidence of radiodermatitis. The main findings were confined to the subcutaneous tissue and consisted of thickened, sclerotic septa composed of both thick and thin collagen bundles, and a lobular panniculitis characterized by lipophagic granulomas and scattered lymphocytes and plasma cells. Additionally, one of the cases showed markedly dilated vascular spaces with the appearance of lymphatics in the upper part of the dermis. Pseudosclerodermatous panniculitis after irradiation is an unusual cutaneous complication of megavoltage radiotherapy that should be distinguished from subcutaneous metastatic disease, cellulitis, or connective tissue diseases involving the subcutaneous fat. The differential diagnosis can be established on the basis of the characteristic histopathologic features of postirradiation pseudosclerodermatous panniculitis.
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PMID:Postirradiation pseudosclerodermatous panniculitis. 1148 17

The skeleton is a common site for the spread of metastatic cancer and skeletal complications are a cause of significant morbidity and mortality. Treatment of skeletal morbidity is therefore an essential component of therapy for cancer patients with bone metastases. Bisphosphonates are currently the treatment of choice for skeletal complications. In a patient diagnosed with bone metastases, skeletal morbidity is evaluated by a number of endpoints known as skeletal related events. These include bone pain, requirement for radiation or surgery to bone, pathologic and radiologic fractures, hypercalcemia, and progression of bone metastases. The efficacy of bisphosphonate treatment is evaluated by their effect on the number and frequency of skeletal-related events. In addition, surrogate markers of bone resorption such as collagen telopeptides or quality of life measurements can be used to monitor therapy, though these do not necessarily reflect skeletal morbidity. Intravenous pamidronate is currently the standard treatment for patients with bone metastases, and is effective in reducing the frequency of a variety of skeletal-related events. The more potent bisphosphonates ibandronate and zoledronate are now being evaluated in this setting. These agents may offer advantages over pamidronate in terms of convenience of administration. Clinical trials underway will determine whether they are equivalent or even superior to pamidronate in reducing skeletal-related events.
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PMID:Analysis of skeletal-related events in breast cancer and response to therapy. 1154 72

Matrix metalloproteinases (MMPs) are essential in several stages of the metastatic process, and in normal bone development and remodeling. We explored whether the interaction between tumor cells and bone leads to changes in MMP and tissue inhibitor of MMP (TIMP) expression thus affecting osteolysis in metastatic bone disease. Using immunohistochemistry we have investigated the MMP/TIMP expression in tumor cells, fibroblasts, osteoblasts and osteoclasts. Thirty one specimens of bone metastasis from breast carcinoma were stained for MMP-1, -2, -9, MT1-MMP and TIMP-1, and -2 and compared with staining in normal breast tissue, primary breast carcinoma and normal bone. Specimens came from patients in three clinical scenarios: from open biopsies without or with pathological fracture, or bone marrow biopsies containing tumor from patients with pancytopenia but without clinical evidence of osteolysis. By bone histomorphometry the latter group showed a heavy tumor load not different from the open biopsy groups but displayed little active bone resorption and low numbers of osteoclasts. Cell type-specific MMP/TIMP expression was observed and the staining patterns were comparable between the three groups of patients. Though no major differences in the MMP/TIMP staining of tumor cells and fibroblasts were observed between bone metastasis and primary tumor, we showed that tumor cells do express MMPs capable of degrading bone matrix collagen. The number and activity of osteoclasts and osteoblasts was increased dramatically in bone metastases, their MMP/TIMP profiles, however, were not different from normal bone, suggesting that the mechanism of bone degradation by osteoclasts is not different from normal bone remodelling.
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PMID:Immunolocalization of matrix metalloproteinases and their inhibitors in clinical specimens of bone metastasis from breast carcinoma. 1159 3


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