Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Walker carcinoma 256 (W256) was reported to induce hypercalcemia dependent on bone metastasis and/or parathyroid hormone-related protein (PTHrP) in the rat, providing a model of the humoral hypercalcemia of malignancy. In this study, after the subcutaneous inoculation of cells of the W256/S line, which is maintained in this laboratory, into young female Wistar Imamichi rats (6 weeks old), serum calcium and phosphorus levels changed only within the control range, whereas serum alkaline phosphatase activity and urinary calcium level significantly increased and urinary phosphorus decreased during the tumor growth, resulting in hypercalciuria and hypophosphaturia. W256/S did not express PTHrP-mRNA, whereas LLC-W256 cells did express it. Serum PTHrP level was not changed in W256/S-bearing rats. Osteoporosis-like changes, bone weight loss, low contents of bone calcium and phosphorus, and a decrease in the bone mineral density (BMD), were observed in the femur 14 days after the tumor inoculation. There was a pronounced decrease in the serum 17 beta-estradiol level during the tumor growth. The reduction of BMD of femurs in W256/S-bearing rats was significantly inhibited by treatment with salmon calcitonin or 17 beta-estradiol. On the basis of these results, W256/S carcinoma-bearing rats seem to be a useful model for osteoporosis of hypoovarianism.
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PMID:Osteoporosis-like changes in Walker carcinoma 256-bearing rats, not accompanied with hypercalcemia or parathyroid hormone-related protein production. 754 Jun 9

The present study was undertaken to clarify in vivo the temporal profile of parathyroid hormone-related peptide (PTHRP) gene expression as well as bone histomorphometric features as a function of tumor growth, using an athymic rat model associated with humoral hypercalcemia of malignancy (HHM). Tumor-bearing animals exhibited hypercalcemia, hypophosphatemia, and increased circulating levels of PTHRP, and died within 3 weeks. Steady-state PTHRP mRNA levels and the transcription rate of PTHRP gene in the tumors were markedly increased with tumor growth. RNAse mapping analysis revealed that both upstream and downstream promoters of the human PTHRP gene were utilized in the tumors and became progressively activated with time. Bone histomorphometric analysis showed that osteoclastic bone resorption was progressively increased throughout the course, whereas osteoblastic bone formation was stimulated more than 2-fold at a very early stage (day 6 after tumor implantation) and then markedly suppressed thereafter on day 12 and day 18 compared with age-matched control animals. These results provide in vivo evidence that PTHRP gene transcription is progressively activated with tumor growth and that activation of osteoblasts does occur at a very early phase of HHM syndrome in contrast to the marked suppression of bone formation at later stages.
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PMID:In vivo evidence for progressive activation of parathyroid hormone-related peptide gene transcription with tumor growth and stimulation of osteoblastic bone formation at an early stage of humoral hypercalcemia of cancer. 774 29

Humoral hypercalcemia of malignancy is a paraneoplastic syndrome believed to be due to production by the tumor of substances that stimulate osteoclastic bone resorption primarily. The human renal cell carcinoma cell line RC-8, grown in nude mice, was investigated for factors involved in renal cancer-induced hypercalcemia. At a tumor load of 200 to 400 mm.3 the mice developed hypercalcemia and hypophosphatemia associated with a rise in serum 1,25-dihydroxyvitamin D concentration and cachexia. The tumor released 1) significant amounts of human interleukin-6 (IL-6) and 2) parathyroid hormone-related peptide (PTHrP) into the circulation. Cancer cells further expressed mRNA for both human IL-6 and PTHrP. No secretion of human tumor necrosis factor-alpha or interleukin-1 beta could be demonstrated in the circulation of the host. Antibodies to IL-6 caused a significant (p = 0.043) inhibition of tumor growth and decreased serum calcium concentrations compared with control animals. Our data suggest that IL-6 is involved, either directly or indirectly, in the development of hypercalcemia in renal cell carcinoma.
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PMID:Hypercalcemia and cosecretion of interleukin-6 and parathyroid hormone related peptide by a human renal cell carcinoma implanted into nude mice. 786 50

Generalized parathyroid hyperplasia with superimposed clonal tumor growth is the most frequent expression of the MEN 1 trait and must be corrected surgically. The Zollinger-Ellison syndrome is an indication for early and aggressive control of hypercalcemia. If gastrin secretion is normal, early parathyroid surgery is usually not required; and to delay the operation will facilitate location of all parathyroid glands, a requisite for successful surgery. The best surgical approach is an extensive primary dissection including thymectomy, followed by total parathyroidectomy with autogenous parathyroid grafting. Parathyroid disease in MEN 2 is less frequent and of later onset. It usually takes secondary consideration to the cure of the C-cell neoplasm. Several other less common hereditary syndromes with parathyroid involvement are reviewed.
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PMID:Management of hyperparathyroidism in the multiple endocrine neoplasia syndromes and other familial endocrinopathies. 791 26

Malignancy-associated hypercalcemia is mainly caused by excessive production of parathyroid hormone-related protein (PTHrP) by the tumor. Using anti-PTHrP-(1-34) monoclonal murine antibody (anti-PTHrP MoAb), we studied whether repeated injection of the homologous antibody would continuously decrease the serum calcium concentration in hypercalcemic nude mice bearing transplanted human PTHrP-producing tumors, leading to prolongation of their survival time. Daily SC injections of anti-PTHrP MoAb decreased the serum calcium concentration almost to within the normal range in nude mice bearing transplanted human PTHrP-producing tumors (T3M-1, EC-GI, PC-3, and FA-6) but not in a nude mouse bearing a transplanted parathyroid carcinoma. The antibody did not affect FA-6 tumor growth either in vitro or in vivo. Pancreatic carcinoma cells (FA-6), which caused the most severe hypercalcemia, were inoculated into 6-week-old nude mice. When severe hypercalcemia (approximately 19 mg/dl) had developed, daily SC injection of anti-PTHrP MoAb was started. Within 18 days of this time point, all untreated tumor-bearing mice (n = 10) died of hypercalcemia and cachexia, whereas all the treated mice (n = 10) showed an increase in body weight and survived for at least 25 days. Histologic examination of the treated mice revealed a marked decrease in osteoclastic bone resorption, without toxicologic findings in the kidney and liver. These results suggest that passive immunization against PTHrP can continuously ameliorate the hypercalcemia and markedly prolong the survival time of severely hypercalcemic, tumor-bearing mice. If a human monoclonal antibody against PTHrP-(1-34) could be developed, then passive immunization would be potentially one of the most effective therapies for patients with malignancy-associated hypercalcemia due to excessive production of PTHrP.
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PMID:Passive immunization with anti-parathyroid hormone-related protein monoclonal antibody markedly prolongs survival time of hypercalcemic nude mice bearing transplanted human PTHrP-producing tumors. 835 67

The antitumor effect of 22-oxa-calcitriol (OCT), a newly developed noncalcemic analogue of calcitriol, was examined in vivo in athymic mice implanted with human breast carcinoma with or without estrogen receptor (ER). In ER-positive MCF-7 tumor, the growth of which was dependent on exogenous estrogen, administration p.o. of OCT as well as the antiestrogen tamoxifen five times a week for 4 weeks suppressed tumor growth in a dose-related fashion. The antitumor effect of 1.0 microgram/kg body weight (BW) OCT (mean +/- SEM of tumor weight in 6 mice: 28 +/- 4% of vehicle-treated group) was comparable to that of 2.0 mg/kg BW tamoxifen (25 +/- 6% of control group). In addition, a synergistic antitumor effect of submaximal doses of OCT and tamoxifen was observed in MCF-7 tumor in vivo as well as in ER-positive breast carcinoma cell lines (MCF-7 and ZR-75-1) in vitro. Administration of OCT p.o. three times a week for 4 weeks also suppressed the growth of ER-negative MX-1 tumor in a dose-dependent manner without raising serum calcium concentrations. The antitumor effect of 1.0 microgram/kg BW OCT (mean +/- SEM of tumor weight in 10 mice: 44 +/- 6% of vehicle-treated group) was greater than that of 500 micrograms/kg BW Adriamycin (71 +/- 6% of control group). These results indicate that OCT suppresses the growth of ER-negative as well as ER-positive breast carcinoma in vivo without causing hypercalcemia and that the antitumor effect of OCT can be enhanced by tamoxifen in an ER-positive tumor. It is suggested that OCT may provide a new strategy, either alone or in combination with other anticancer drugs, for systemic adjuvant therapy of breast carcinoma regardless of ER status.
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PMID:Antitumor effect of 22-oxa-calcitriol, a noncalcemic analogue of calcitriol, in athymic mice implanted with human breast carcinoma and its synergism with tamoxifen. 849 16

We examined the activity of UFT, ADM and MMC, which are used for colon tumors, in terms of their prolongation of the survival period, growth inhibition of the primary tumor and improvement of cachexia in murine cancer cachexia model. The mean survival period of Colon 26, mouse adenocarcinoma bearing mice was 25.0 +/- 4.9 days. The maximal ILS value of the UFT administered group was 103.2%, against 7.2 and 26.0%, respectively, ADM and MMC maximal ILS value. For therapeutic activity of hypercalcemia, UFT was superior to other drugs, although all drugs showed equivalent tumor growth inhibitory activity. These findings indicate that UFT can prolong the survival period due to improvement of cancer cachexia. Therefore, we measured plasma interleukin-6 (IL-6) and found that UFT-administration lowered the plasma IL-6 level more than other drugs. Moreover, the prostaglandin E2 (PGE2) level in the tumor was significantly decreased only by UFT-administration. Since PGE2 has been shown to enhance IL-6 production from Colon 26 in vitro, it was speculated that UFT improve cachexia and prolongs life by decreased IL-6 resulting from decreased PGE2.
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PMID:[Prolongation of survival and antitumor activity of antitumor drugs in murine cancer cachexia model]. 867 37

We describe a 7-month-old boy who manifested severe hypercalcemia associated with mesenchymal neoplasm. A huge hypervascular tumor on the neck had been detected in prenatal ultrasonography. Surgical removal of the entire tumor at birth was not indicated, because the tumor was diagnosed as hemangioma. Chemotherapy and radiotherapy were attempted, but there was no effect on tumor growth. When the infant was 6 months old, the serum calcium level increased rapidly, associated with the expansion of the tumor. Hypophosphatemia due to phosphaturia was also observed. Serum PTH was undetectable, whereas the serum concentration of carboxyl-terminal (C-terminal) fragments of PTH-related protein (PTH-rP) was markedly elevated. Northern blot analysis and immunostaining demonstrated the expression of PTH-rP in the tumor. The tumor was transplantable to nude mice and caused elevation of circulating PTH-rP in the animals. Histological examination of the patient's bone revealed an increased number of osteoclasts. These findings were consistent with humoral hypercalcemia of malignancy caused by the excess production of PTH-rP. The tumor was identified histologically as infantile fibrosarcoma, which has not been reported as a cause of humoral hypercalcemia of malignancy to date. The expression of PTH/PTH-rP receptor messenger ribonucleic acid was detected in the tumor by the RT-PCR, suggesting that PTH-rP may have exerted its effect in the tumor in an autocrine/paracrine manner. In addition to the systemic effect of PTH-rP manifested as hypercalcemia, the PTH-rP secreted from the neoplasm could have been a local factor involved in the growth of the tumor.
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PMID:Hypercalcemia associated with infantile fibrosarcoma producing parathyroid hormone-related protein. 877 81

Hypercalcemia is a well known complication of renal cell carcinoma (RCC). As RCCs can produce IL-6, and IL-6 may stimulate bone resorption and cause mild hypercalcemia, we examined whether IL-6 is involved in renal cancer-associated hypercalcemia in vivo. Three human renal cell carcinoma tumor lines (RC-8, RC-9, and NC-65) growing in nude mice were studied. Tumors were implanted s.c., and parameters of bone metabolism and serum human IL-6 levels were determined in relation to tumor volume (TV). All three tumor lines secreted human IL-6, although in different quantities. The maximum level of IL-6 in RC-8 was 434 pg/ml (TV, 200 mm3), that in RC-9 was 81 pg/ml (TV, 1800 mm3), and that in NC-65 was 2368 pg/ml (TV, 1800 mm3). Hypercalcemia developed in RC-8 and RC-9 tumor-bearing animals, but not in NC-65-bearing animals. The hypercalcemia in both RC-8 and RC-9 tumor lines was associated with elevated levels of PTH-related peptide (PTHrP) and loss of trabecular bone volume. Serum calcium and phosphate concentrations showed an almost linear relationship with plasma PTHrP independently of the tumor line and serum IL-6 levels. No hypercalcemia occurred in the NC-65 animals, which had the highest levels of IL-6, but no detectable plasma PTHrP and PTHrP messenger RNA expression in the tumor. Administration of neutralizing antibodies to IL-6 to RC-8 animals normalized serum calcium concentrations and PTHrP values and induced a significant inhibition of tumor growth. No such effect on tumor growth of anti-IL-6 was seen in the other two tumor lines. The normalization of serum calcium in RC-8 mice is most likely attributed to the growth-inhibiting effect of anti-IL-6 on RC-8 tumor. We conclude that IL-6 secreted by RCC does not contribute directly to hypercalcemia, but may enhance hypercalcemia by stimulating the tumor growth of a subpopulation of PTHrP-secreting carcinomas.
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PMID:The role of interleukin-6 in the induction of hypercalcemia in renal cell carcinoma transplanted into nude mice. 911 82

Parathyroid hormone related peptide (PTHRP) is the major causal agent in the syndrome of malignancy-associated hypercalcemia (MAH). Several studies have shown that PTHRP production is increased in response to growth factors and oncogenes, such as Tpr-Met, that are associated with the tyrosine kinase signaling pathway. Using site-directed mutagenesis of Tpr-Met and chemical inhibitors of phosphotidylinositol-3 kinase and Ras isoprenylation, we demonstrated previously that induction of PTHRP is mediated via the Ras signaling pathway. In the present study, we have directly investigated the role of the Ras oncogene in MAH. As a model system, we used Fisher rat 3T3 fibroblasts stably transfected with a Ras oncogene (Ras-3T3). Ras transfection enhanced PTHRP production 5-10-fold in these cells, and inoculation of this cell line into nude mice led to the development of hypercalcemia within 2 weeks. We used this system to evaluate the effect of a potent inhibitor of Ras processing, B-1086, on cell growth, PTHRP production, plasma calcium, and tumor growth. Treatment of Ras-3T3 cells in vitro with B-1086 at 0.1-10 microg/ml produced a significant reduction in PTHRP mRNA expression and PTHRP secretion and a significant decrease in cell proliferation. Treatment in vivo of BALB/c/nu/nu mice bearing Ras-3T3 tumors with B-1086 resulted in a significant inhibition in tumor growth. In addition, this treatment produced near normalization of serum Ca2+, a significant decrease in plasma PTHRP, and a reduction in tumoral PTHRP mRNA levels. These results show that the Ras pathway is involved in PTHRP production by tumors, identifies Ras as a potential target for treatment of MAH, and demonstrates Ras processing inhibitors as candidate therapeutic agents against this syndrome.
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PMID:Induction of parathyroid hormone-related peptide by the Ras oncogene: role of Ras farnesylation inhibitors as potential therapeutic agents for hypercalcemia of malignancy. 937 63


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