Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Paraneoplastic manifestations are present in up to 20% of patients with renal cell carcinoma (RCC). There is convincing evidence that RCC tumor cells elaborate proteins that serve as mediators of endocrine (eg, ectopic production of parathyroid hormone-related protein or erythropoietin) as well as nonendocrine paraneoplastic syndromes. A paraneoplastic syndrome may be the initial clinical presentation of RCC in a significant number of patients, and recognition of these syndromes may facilitate early diagnosis. Most paraneoplastic syndromes associated with RCC remit after resection of the primary RCC or treatment of metastatic sites. The natural history of metastatic RCC is extremely variable. A significant proportion of patients may survive several years with slowly progressing metastatic disease. In these patients, the accurate diagnosis and management of paraneoplastic syndromes may be important in palliative management. Except for hypercalcemia, conventional medical therapies are seldom helpful. Other paraneoplastic manifestations of RCC include cachexia, fever, hepatic dysfunction, anemia, and amyloidosis, although our understanding of the underlying pathophysiology remains incomplete.
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PMID:Paraneoplastic manifestations of renal cell carcinoma. 894 20

Parathyroid hormone-related protein (PTHrP) has been shown to be the primary factor responsible for humoral hypercalcemia of malignancy. Recently PTHrP has been shown to be an early-response gene that may be involved in cellular proliferation or differentiation. In addition, PTHrP has been implicated in the pathogenesis of bone metastases. Bone metastases are a significant complication in patients with prostate cancer. We compared the expression of PTHrP by immunohistochemical staining using a monoclonal antibody directed against epitope between amino acids [53-64] in benign prostatic hyperplasia (BPH) with that in various stages of prostate cancer. Tissue sections were obtained on formalin-fixed paraffin-embedded blocks from BPH, well-differentiated prostate cancer, poorly differentiated prostate cancer, lymph node metastases (n = 15 each), and normal prostate (n = 2). In the normal prostate tissue there was no staining observed. In BPH, 13 of 15 tissue samples were positive for PTHrP immunoreactivity. An average of 33% of the cells stained positive with 1+ intensity. All samples from prostate cancer stained positive for PTHrP. In the samples from well-differentiated prostate cancer, an average of 87% of cells stained positive for PTHrP, whereas 100% of cells were positive in poorly differentiated and metastatic tumors. The intensity of staining was 3+ in well-differentiated tumors and 4+ in poorly differentiated tumors. Therefore, the expression of PTHrP is enhanced in prostate cancer as compared with BPH and is greater in poorly differentiated carcinoma as compared with the well-differentiated tumors. The role of PTHrP in the pathogenesis of prostate cancer deserves further study.
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PMID:Enhanced expression of parathyroid hormone-related protein in prostate cancer as compared with benign prostatic hyperplasia. 895 5

Cancers from patients with tumor-induced hypercalcemia usually produce a circulating factor that mimics the parathyroid hormone activity, termed parathyroid hormone-related protein. Incidence of tumor-induced hypercalcemia appears to be high in patients with squamous cell carcinoma of the esophagus, and the presence of parathyroid hormone-related protein have been shown in some primary esophageal cancers. In the present study, we have investigated the presence of parathyroid hormone-related protein in a patient with metastasized squamous cell carcinoma of the esophagus complicated with tumor-induced hypercalcemia. Protein was searched by immunohistochemistry, and messenger RNA was investigated by reverse transcriptase-polymerase chain reaction and S1 nuclease assay. Both messenger RNA and protein were detected in hepatic metastases, whereas normal esophageal mucosa and primary cancer did not express detectable protein or messenger RNA using the S1 nuclease assay. Reverse transcriptase-polymerase chain reaction was positive in all these tissues, including normal esophageal mucosa. In conclusion, the present case suggests that tumor-induced hypercalcemia due to esophageal squamous cell carcinoma may be caused by parathyroid hormone-related protein mostly released by liver metastases.
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PMID:Parathyroid hormone-related protein in an esophageal squamous cell carcinoma with tumor-induced hypercalcemia. 904 Feb 21

A case of ovarian clear cell carcinoma associated with hypercalcemia is reported. A 67-year-old woman developed the lung metastasis 8 months after primary surgery. The patient manifested symptoms of humoral hypercalcemia of malignancy (HHM) during the last 3 months of her clinical course. Serum and urinary C-terminus parathyroid hormone-related protein (PTHrP) levels were remarkably high. No increase in interleukin (IL) 1beta, tumor necrosis factor (TNF) alpha, vitamin D3 metabolites or intact PTH was detected. Pamidronate disodium treatment was transiently suppressed her serum calcium level. The patient died despite seven courses of chemotherapy. Autopsy showed multiorgan metastases and accelerated osteoclastic bone resorption; skeletal metastasis was not detected. Immunohistochemical analysis clearly showed the localization of PTHrP at both the primary and metastatic sites. The transcripts of PTHrP at pulmonary metastatic sites were revealed by in situ hybridization and the reverse transcription polymerase chain reaction (RT-PCR) method. PTHrP was the causative factor for HHM in this case. It is therefore suggested that hypercalcemia may have occurred after PTHrP production had overcome the homeostatic level during the terminal stage, although PTHrP production continued irrespective of the patient's serum calcium level.
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PMID:In situ detection of parathyroid hormone-related protein in ovarian clear cell carcinoma. 904 5

There are three principal disturbances in bone remodelling that occur in neoplasia affecting the skeleton. The first is an increase in bone turnover that in solid tumors may be confined to sites of metastases or be a generalized phenomenon, most likely related to the secretion of parathyroid hormone-related protein. In the bone remodelling sequence, bone resorption precedes formation, so that increases in turnover result in substantial skeletal deficits more marked at cancellous than cortical bone sites. The second abnormality in bone remodelling is an imbalance between the amount resorbed and that formed at each remodelling site. This is a conspicuous feature of myelomatosis with moderate grades of plasma cell infiltration. The third phenomenon is the process of uncoupling. In osteolytic disease this is associated with the creation of erosion cavities that are never subsequently repaired. Progressive waves of bone resorption result in the destruction of skeletal elements and focal osteolysis. Osteosclerotic metastases formed by uncoupled bone formation represent the deposition of new bone either on quiescent bone surfaces or arising from stromal condensations within the marrow cavity. In solid tumors biopsy evidence suggests that uncoupled bone resorption and formation occur within the same metastases and that the radiographic expression (osteosclerosis, osteolysis) depends on the predominant component. The understanding that abnormalities of skeletal metabolism are mediated by authentic bone cells raises the possibility that skeletal specific markers of bone turnover might be utilized for the diagnosis of metastases, to assess the skeletal prognosis, or to monitor treatment. A variety of skeletal markers have been assessed. The pyridinium crosslinks currently provide the markers of greatest predictive value. Although they have high specificity, their sensitivity is low (< 30%). This indicates that many individuals with skeletal metastases would be missed. In contrast, skeletal markers have proven invaluable in the assessment of the natural history of the disease and response to intervention. They have been particularly useful in assessing the pharmacodynamics of bisphosphonate treatment. However, their day-to-day precision is sufficiently low that they are of limited value in the monitoring of individuals.
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PMID:Bone turnover and biochemical markers in malignancy. 936 20

The discovery of parathyroid hormone-related protein (PTH-rP) arose from interest in the mechanisms by which certain cancers cause hypercalcemia without necessarily metastasizing to bone. The humoral hypercalcemia of malignancy (HHM) had for a long time been ascribed to inappropriate production of parathyroid hormone (PTH) by cancers. The amino-terminal portions of PTH-rP and PTH have essentially identical actions through a common receptor for PTH/PTH-rP: to elevate plasma calcium by promoting bone resorption and decreasing calcium excretion. Assays for plasma PTH-rP fail to detect protein convincingly in normal plasma, but measurable levels have been found in up to 100% of patients with HHM, in 75% of patients with breast carcinoma metastatic to bone, and in some hypercalcemic patients with miscellaneous cancers. Whereas PTH-rP clearly functions as a hormone in those cancers in which it is produced in excess, in normal circumstances it is produced locally in many tissues in which it is a paracrine effector. There appears to be little doubt that PTH-rP is the major mediator of hypercalcemia in patients with HHM, although it is possible that other factors (e.g., bone resorbing cytokines) also could contribute in some patients. In the case of breast carcinoma, another possible role arises for PTH-rP. The high incidence of PTH-rP production by primary breast carcinomas, elevated plasma levels in 60% of those with hypercalcemia and lytic metastases, and higher incidence of PTH-rP production in skeletal versus those with nonskeletal metastases have led to the hypothesis that PTH-rP might contribute to breast carcinoma growth in bone. Experimental evidence currently is available to support this hypothesis. The discovery of PTH-rP has contributed greatly to current understanding of the skeletal complications of cancer.
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PMID:Parathyroid hormone-related protein and hypercalcemia. 936 23

Parathyroid hormone-related protein (PTH-rP) was purified and cloned 10 years ago as a factor responsible for the hypercalcemia associated with malignancy. Clinical evidence supports another important role for PTH-rP in malignancy as a mediator of the bone destruction associated with osteolytic metastasis. Patients with PTH-rP positive breast carcinoma are more likely to develop bone metastasis. In addition, breast carcinoma metastatic to bone expresses PTH-rP in >90% of cases, compared with only 17% of metastasis to nonbone sites. These observations suggest that PTH-rP expression by breast carcinoma cells may provide a selective growth advantage in bone due to its ability to stimulate osteoclastic bone resorption. Furthermore, growth factors such as transforming growth factor-beta (TGF-beta), which are abundant in bone matrix, are released and activated by osteoclastic bone resorption and may enhance PTH-rP expression and tumor cell growth. To investigate the role of PTH-rP in the pathophysiology of breast carcinoma metastasis to bone, the human breast carcinoma cell line MDA-MB-231 was studied in a murine model of human breast carcinoma metastasis to bone. A series of experiments were performed in which 1) PTH-rP secretion was altered, 2) the effects of PTH-rP were neutralized, or 3) the responsiveness to TGF-beta was abolished in MDA-MB-231 cells. Cultured MDA-MB-231 cells secreted low amounts of PTH-rP that increased fivefold in response to TGF-beta. Tumor cells inoculated into the left cardiac ventricle of nude mice caused osteolytic metastasis similar to that observed in humans with breast carcinoma. When PTH-rP was overexpressed in the tumor cells, bone metastases were increased. MDA-MB-231 cells transfected with the cDNA for human preproPTH-rP secreted a tenfold greater amount of PTH-rP and caused significantly greater bone metastases when inoculated into the left cardiac ventricle of female nude mice compared with parental cells. In contrast, when the biologic effects of PTH-rP were neutralized or its production was suppressed, such metastases were decreased. Treatment of mice with a neutralizing monoclonal antibody to human PTH-rP resulted in a decrease in the development and progression of bone metastasis due to the parental MDA-MB-231 cells. Similar results were observed when mice were treated with dexamethasone, a potent glucocorticoid that suppresses production of PTH-rP by the MDA-MB-231 cells in vitro. The role of bone-derived TGF-beta in the development and progression of bone metastasis was studied by transfecting MDA-MB-231 cells with a cDNA encoding a TGF-beta type II receptor lacking a cytoplasmic domain, which acts as a dominant negative to block the cellular response to TGF-beta. Stable clones expressing this mutant receptor (MDA/TbetaRIIdeltacyt) did not increase PTH-rP secretion in response to TGF-beta stimulation compared with controls of untransfected MDA-MB-231 or those transfected with the empty vector. Mice inoculated into the left cardiac ventricle with MDA/TbetaRIIdeltacyt had fewer and smaller bone metastases as assessed radiographically and histomorphometrically compared with controls. Taken together, these data suggest that PTH-rP expression by breast carcinoma cells enhance the development and progression of breast carcinoma metastasis to bone. Furthermore, TGF-beta responsiveness of breast carcinoma cells may be important for the expression of PTH-rP in bone and the development of osteolytic bone metastasis in vivo. These interactions define a critical feedback loop between breast carcinoma cells and the bone microenvironment that may be responsible for the alacrity with which breast carcinoma grows in bone.
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PMID:Parathyroid hormone-related protein and bone metastases. 936 24

A significant percentage (50-70%) of patients with metastatic breast carcinoma (MBC) will have disease involving the bony skeleton. Clonal selection mediated by parathyroid hormone-related protein and other factors may explain the high incidence of osseous metastases in MBC. The presence of specific growth factors and cytokines in the microenvironment of bone may contribute to the successful establishment and growth of metastatic lesions and also might determine response or resistance of these lesions to chemotherapy or hormonal therapy. Osteolytic bone lesions in MBC frequently give rise to serious clinical problems including bone pain, pathologic fracture, hypercalcemia, and neurologic complications. MBC often is treated with systemic chemotherapy or hormonal therapy. The purpose of this article was to review the recent published literature describing the impact of systemic chemotherapy and hormonal therapy of MBC on the response of bone lesions and their clinical course and complications. Evaluating the response of bone lesions can be problematic and may be complicated by the phenomenon of "tumor flare" that may be observed with either chemotherapy or hormonal therapy. Use of the International Union Against Cancer criteria for the response of bone lesions is recommended. Several studies report objective responses (20-60%) of lytic bone metastases to standard combination chemotherapy regimens such as cyclophosphamide, methotrexate, and 5-fluorouracil and cyclophosphamide, doxorubicin, and 5-fluorouracil, mitoxantrone and 5-FU, newer combinations, and single agents including paclitaxel and docitaxel but responses to vinorelbine may be less frequent. Complete responses of bone lesions to chemotherapy are rare but partial responses and disease stabilization can lead to long term patient benefit. A series from the M. D. Anderson Cancer Center of patients with bone metastases treated with 5-FU, doxorubicin, and cyclophosphamide chemotherapy reported a median duration of response of 14 months. In a recent multicenter study of 195 patients with lytic lesions from MBC treated with chemotherapy, the objective response rate (complete response + partial response) in bone was 18% and 65% of the patients developed at least 1 morbid skeletal event with a median onset of 7.0 months from the start of chemotherapy. Hormone-dependent breast carcinoma has a proclivity to metastasize to bone. In earlier studies comparing aminoglutethimide or medroxyprogesterone acetate with tamoxifen, a higher response rate of bone metastases was observed for the first two agents. However, in more recent studies comparing newer aromatase inhibitors, such as anastrozole, fadrozole, and letrozole, with megestrol acetate, there were no significant differences in rates of response in bone. Patients with MBC with bony lesions respond to both chemotherapy and hormonal therapy and can have a prolonged survival. Therefore such patients are in a more favorable position to benefit from adjunctive supportive therapy such as bisphosphonates intended to reduce skeletal morbidity.
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PMID:Issues concerning the role of chemotherapy and hormonal therapy of bone metastases from breast carcinoma. 936 31

About 1-2% of melanoma patients develop hypercalcemia. We report hypercalcemia without bone metastasis in a 46-year-old woman with advanced melanoma. The hypercalcemia was associated with elevated serum parathyroid hormone-related protein (PTHrP) levels. An even higher concentration (10 times the serum level) in pleural effusion caused by pleural metastases implied that the source of the increased circulating PTHrP was the melanoma. Immunohistochemical staining of paraffin sections, performed using a monoclonal antibody (9H7) against the peptide sequence 109-141 of human PTHrP, detected PTHrP in the cytoplasm and nucleoli of melanoma cells in an autopsy specimen but not in specimens from this patient prior to onset of hypercalcemia. Considering the evidence, it is very likely that PTHrP production by melanoma caused hypercalcemia in this patient.
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PMID:Hypercalcemia due to parathyroid hormone-related protein secretion by melanoma. 962 20

We describe a 43-year-old Japanese female who developed hypercalcemia associated with malignant melanoma. The patient underwent three resections of tumors on her groin and buttock secondary to a bathing trunk congenital nevus, and the histopathological findings showed benign congenital nevi. At the age of 42 years, she developed a malignant melanoma under the giant pigmented nevus in her groin. Fourteen months after the diagnosis of melanoma, she developed metastases to the lung, para-aortic lymph nodes and bones accompanied by hypercalcemia resulting from a remarkable increase in the serum level of parathyroid hormone-related protein (PTHrP). The patient died from acute renal and respiratory failure. In addition, we analyzed serum levels of calcium and PTHrP in 19 patients with advanced malignant melanoma. Seven patients had hypercalcemia, and 3 had increased serum levels of PTHrP.
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PMID:Hypercalcemia in a patient with malignant melanoma arising in congenital giant pigmented nevus. A case of increased serum level of parathyroid hormone-related protein. 969 91


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