Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026764 (multiple myeloma)
 36,148 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The profound effects of the bisphosphonates on calcium metabolism were discovered over 30 years ago, and they are now well established as the major drugs used for the treatment of bone diseases associated with excessive resorption. Their principal uses are for Paget disease of bone, myeloma, bone metastases, and osteoporosis in adults, but there has been increasing and successful application in pediatric bone diseases, notably osteogenesis imperfecta. Bisphosphonates are structural analogues of inorganic pyrophosphate but are resistant to enzymatic and chemical breakdown. Bisphosphonates inhibit bone resorption by selective adsorption to mineral surfaces and subsequent internalization by bone-resorbing osteoclasts where they interfere with various biochemical processes. The simpler, non-nitrogen-containing bisphosphonates (eg, clodronate and etidronate) can be metabolically incorporated into nonhydrolysable analogues of adenosine triphosphate (ATP) that may inhibit ATP-dependent intracellular enzymes. In contrast, the more potent, nitrogen-containing bisphosphonates (eg, pamidronate, alendronate, risedronate, ibandronate, and zoledronate) inhibit a key enzyme, farnesyl pyrophosphate synthase, in the mevalonate pathway, thereby preventing the biosynthesis of isoprenoid compounds that are essential for the posttranslational modification of small guanosine triphosphate (GTP)-binding proteins (which are also GTPases) such as Rab, Rho, and Rac. The inhibition of protein prenylation and the disruption of the function of these key regulatory proteins explains the loss of osteoclast activity. The recently elucidated crystal structure of farnesyl diphosphate reveals how bisphosphonates bind to and inhibit at the active site via their critical nitrogen atoms. Although bisphosphonates are now established as an important class of drugs for the treatment of many bone diseases, there is new knowledge about how they work and the subtle but potentially important differences that exist between individual bisphosphonates. Understanding these may help to explain differences in potency, onset and duration of action, and clinical effectiveness.
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PMID:Bisphosphonates: mode of action and pharmacology. 1733 36

A 62 year old woman was referred to our hospital because of acute renal and liver dysfunction. Prior to admission, she had already been started on hemodyalysis filtration(HDF). She showed facial edema and lumbar pain caused by an Ll compressive fracture. Laboratory examinations revealed hypercalcemia (13.2 mg/dL), hyperammonemia (297 microg/dL) and her serum creatinine, blood urea nitrogen and total bilirubin levels were 3.9 mg/dL, 37.4 mg/dL and 3.2 mg/dL, respectively. Among the components of immunoglobulin, IgA was increased, while IgG and IgM were decreased. Serum immunoelectrophoresis revealed the presence of the IgA kappa type of M component. Punched out lesions were noted on her head radiography. Severe plasmacytosis (60-70 % of total cells) were observed by a bone marrow aspiration test, indicating the diagnosis of multiple myeloma. Steroid pulse therapy was started with dexamethasone (40 mg/day, 3 days), and plasma exchange was performed 8 times with continuous HDF. These treatments failed to control hemodynamics and she died of disseminated intravascular coagulation (DIC). Autopsy demonstrated amyloid-like depositions in perisinusoidal space in the liver. In the kidney, there were nodular lesions in the glomeruli, and depositions in the basement membrane of the uriniferous tubuli. Congo red staining of these organs for amyloid yielded negative results. Immunohistochemical staining gave positive results for IgA and kappa. Electron microscopy revealed granular electron deposits in the glomeruli and tubular basement membrane as well. Taken altogether, the diagnosis of the patient could be light chain deposition disease (LCDD).
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PMID:[A case of acute renal and liver dysfunction with light chain deposition disease]. 1757 93

New strategies are needed to overcome the resistance of multiple myeloma (MM) to dexamethasone (Dex). Several recent in vitro studies demonstrated the antitumor effect of nitrogen-containing amino-bisphosphonates (N-BPs) in various tumor cell lines. Inhibition of the prenylation of small G proteins is assumed to be one of the principal mechanisms by which N-BPs exert their effects. There have been few reports on N-BP treatment of MM cells that are resistant to Dex. Additionally, it is not known how small G proteins are altered in N-BP-treated MM cells. In this study, we evaluated the effect of the most potent N-BP, zoledronate (ZOL), on a Dex-resistant human MM cell subline (Dex-R) that we established from the well-documented RPMI8226 cell line. ZOL reduced the viability and induced apoptosis of Dex-R cells. Some of the ZOL-treated RPMI8226 cells and ZOL-treated Dex-R cells were elongated; however, elongated cells were not seen among the Dex-treated RPMI8226 cells. Furthermore, we found that portions of the small G proteins, Rho and Rap1A, were unprenylated in the ZOL-treated MM cells. Geranylgeraniol reduced the above-mentioned ZOL-induced effects. These findings suggest that ZOL may be beneficial for the treatment of Dex-resistant MM by suppressing the processing of RhoA and Rap1A.
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PMID:Zoledronate has an antitumor effect and induces actin rearrangement in dexamethasone-resistant myeloma cells. 1833 95

Nitrogen-containing bisphosphonates (nBPs) are bone-specific agents that inhibit farnesyl diphosphate synthase. nBPs' strong affinity for bone, and not for other tissues, makes them potent inhibitors of bone resorption and bone remodeling activity, with limited potential for side-effects in non-skeletal tissues. Five nBPs are currently approved in the United States. The primary indications are for treatment of osteoporosis (alendronate, ibandronate, and risedronate) and treatment/prevention of skeletal-related events (SREs) in multiple myeloma and breast and prostate cancer patients (ibandronate, pamidronate, and zoledronic acid). nBPs are the most efficacious drugs available for these diseases, reducing osteoporotic fracture risk by 50-60% in persons with low bone mass or prior osteoporotic fracture, and SREs by one-third in cancer patients. The absorbed nBP dose for cancer patients is from seven to ten times that in osteoporosis patients. nBPs are unique in that they first exert profound pharmacodynamic effects long after their blood levels reach zero. Current pharmacokinetic studies indicate that approximately half of any nBP dose reaches the skeleton, with an early half-life of ten days, and a terminal half-life of about ten years. Practical study design limitations and theoretical considerations suggest that both the half-life and the amount of nBP retained in the skeletons of patients on long-term nBP therapy are substantially overestimated by extrapolation directly from current pharmacokinetic data. In fact, the amount of nBP being released from skeletal tissues of long-term-treated patients, particularly in osteoporosis patients, becomes insufficient to maintain full pharmacodynamic efficacy relatively soon after dosing is interrupted.
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PMID:Mechanism of action, pharmacokinetic and pharmacodynamic profile, and clinical applications of nitrogen-containing bisphosphonates. 1795 91

The bisphosphonates (BPs) are well established as the treatments of choice for disorders of excessive bone resorption, including Paget's disease of bone, myeloma and bone metastases, and osteoporosis. There is considerable new knowledge about how BPs work. Their classical pharmacological effects appear to result from two key properties: their affinity for bone mineral and their inhibitory effects on osteoclasts. Mineral binding affinities differ among the clinically used BPs and may influence their differential distribution within bone, their biological potency, and their duration of action. The inhibitory effects of the nitrogen-containing BPs (including alendronate, risedronate, ibandronate, and zoledronate) on osteoclasts appear to result from their inhibition of farnesyl pyrophosphate synthase (FPPS), a key branch-point enzyme in the mevalonate pathway. FPPS generates isoprenoid lipids used for the posttranslational modification of small GTP-binding proteins essential for osteoclast function. Effects on other cellular pathways, such as preventing apoptosis in osteocytes, are emerging as other potentially important mechanisms of action. As a class, BPs share several common properties. However, as with other classes of drugs, there are obvious chemical, biochemical, and pharmacological differences among the various individual BPs. Each BP has a unique profile that may help to explain potential important clinical differences among the BPs, in terms of speed of onset of fracture reduction, antifracture efficacy at different skeletal sites, and the degree and duration of suppression of bone turnover. As we approach the 40th anniversary of the discovery of their biological effects, there remain further opportunities for using their properties for medical purposes.
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PMID:Bisphosphonates: an update on mechanisms of action and how these relate to clinical efficacy. 1805 45

Nitrogen-containing biphosphonates are a group of medications that are increasingly used in the management of Paget's disease, fibrous dysplasia, osteoporosis, multiple myeloma and metastatic prostate or breast cancer bone disease. On 2004 it was established that nitrogen-containing biphosphonates may induce jaw osteonecrosis and since then, a substantial number of publications has supported this finding. Jaw osteonecrosis may be asymptomatic, lasting for about a year or symptomatic, accompanied with mild or severe pain. Jaw osteonecrosis usually results in patients with poor dental hygiene, or subjected to invasive dental procedures. Its incidence increases with the length of nitrogen-containing biphosphonates treatment and appears to be higher for the Zometa(TM) users. It is important to early recognize this entity, since early intervention can make a significant difference to the outcome of this debilitating side effect. We here report three patients who had a positive technetium-99m methylene diphosphonate ((99m)Tc-MDP) bone scan. One of these patients also had osteomyelitis and was treated aggressively. The other two were treated in a more conservative manner. Detailed dental examination supported the scintigraphic findings. Biopsy was performed only in one patient and also offered specimens for antibiotic cultures. In discussion, jaw biopsy is a debatable procedure in the setting of jaw osteonecrosis and many consider that it should be avoided in most cases, except if it is necessary to establish the diagnosis and suggest antibiotic treatment by obtaining samples for bacterial cultures. Although axial tomography and magnetic resonance imaging are useful in defining the extent of the disease, 3-phase (99m)Tc-MDP bone scan is the most sensitive imaging modality pinpointing the disease at its early stages. In conclusion, a 3-phase (99m)Tc-MDP scan with anterior and lateral views of the skull is indicated in all symptomatic or asymptomatic patients, with a history of long-term nitrogen-containing biphosphonate treatment, since this may lead to an early detection of the disease.
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PMID:Jaw uptake of technetium-99 methylene diphosphonate in patients on biphosphonates: a word of caution. 1808 61

Zoledronic acid (Zometa is a third-generation nitrogen-containing parenteral bisphosphonate indicated for the treatment of bone metastases due to solid tumours or multiple myeloma and for hypercalcaemia of malignancy (HCM). In patients with advanced breast or prostate cancer, zoledronic acid 4 mg every 3-4 weeks for up to 15 months significantly reduced the proportion of patients with > or =1 skeletal-related event (SRE), excluding HCM, compared with placebo. In patients with advanced breast cancer or multiple myeloma, the incidence of SREs was similar in patients treated with zoledronic acid 4 mg or pamidronic acid 90 mg every 3-4 weeks for up to 25 months but, in breast cancer patients, zoledronic acid reduced the risk of SREs, including HCM, by an additional 20% compared with pamidronic acid. In modelled cost-utility studies comparing direct costs based on efficacy and resource-use data from these and/or other trials, results have varied. In the most recent study performed from the perspective of the UK NHS and modelled over a 10-year treatment period in women with advanced breast cancer, intravenous zoledronic acid and oral ibandronic acid were dominant over no treatment. Intravenous zoledronic acid was the most cost effective, in terms of incremental costs per QALY gained, followed by oral ibandronic acid, intravenous pamidronic acid and intravenous ibandronic acid. Two other modelled analyses in patients with advanced breast cancer, also conducted from the perspective of the NHS, evaluated the cost utility of three bisphosphonate therapies in patients receiving hormonal therapy or intravenous chemotherapy. Analyses were modelled over 14.3 months (i.e. expected survival) and assumptions varied markedly from results in clinical breast cancer trials. Also, efficacy assumptions for zoledronic acid were not based on clinical trials with the drug. The results of these analyses suggest that oral ibandronic acid is more cost effective than intravenous zoledronic acid and intravenous pamidronic acid in terms of incremental cost per QALY gained. In a global, 15-month modelled cost-effectiveness analysis of patients with advanced prostate cancer, conducted from a third-party perspective, the incremental cost per QALY gained for zoledronic acid versus no treatment was $US159 200 (year 2000 value), which is about 3-fold greater than commonly accepted thresholds for cost effectiveness. In conclusion, a recent modelled economic analysis suggests that intravenous zoledronic acid 4 mg is dominant relative to no treatment in the management of bone metastases in patients with advanced breast cancer. In contrast, in patients with advanced prostate cancer, the incremental cost per QALY gained for zoledronic acid 4 mg versus no treatment was predicted to be higher than commonly accepted thresholds. Compared with other bisphosphonates in the setting of advanced breast cancer, intravenous zoledronic acid was more cost effective than oral or intravenous ibandronic acid and intravenous pamidronic acid in one study, but less cost effective than oral ibandronic acid in another. Further efficacy and economic data comparing intravenous zoledronic acid with oral ibandronic acid are needed. Meanwhile, zoledronic acid appears to be the most cost effective intravenous bisphosphonate for the management of bone metastases in patients with advanced breast cancer and possibly in patients with different types of advanced solid tumours.
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PMID:Zoledronic acid: a pharmacoeconomic review of its use in the management of bone metastases. 1828 18

The delineation of the hematological malignancies began near the end of the first third of the 19th century with the recognition of the similarity among cases with lymph node tumors and an enlarged spleen (Hodgkin's disease). Descriptions of chronic and acute leukemia and myeloma followed thereafter. In the first years of the 20th century the discovery of x-radiation permitted palliative orthovoltage radiation therapy of Hodgkin's disease. Following World War II, legitimate drug therapy for the hematological malignancies was introduced: nitrogen mustard, adrenocorticotropic hormone and cortisone acetate, and anti-folic acid derivatives, initially aminopterin. Today, about 14 classes of drugs (different mechanisms of action) and >50 individual agents are being used, with others under study. Several examples of agents targeting specific transcription factors or oncoproteins have been introduced. Despite remarkable progress, including the ability to cure acute leukemia in about 70% of children, cure several genetic variants of acute myelogenous leukemia in younger adults, cure some cases of lymphoma in children and younger adults, and induce prolonged remission in many affected persons, the majority of patients face an uncertain outcome and shortened life. Thus, we have much to do in the next several decades. The significant hurdles we must overcome include: the apparent infrequency of an exogenous cause that can be avoided, the exponential increase in incidence rates with age and the dramatic negative effect of aging on the results of treatment, the challenge of one trillion or more disseminated cancer cells among which are a smaller population of cancer stem cells, the profound genetic diversity of the hematological malignancies (apparently hundreds of unique genetic primary lesions), the redundant growth and survival pathways defining the cancer phenotype, the decreasing market for pharmaceutical companies as therapy becomes more specific (fewer target patients) and drug development costs become more expensive, and the significant negative long-term effects of current therapy on both children and adults. These challenges will be gradually overcome, if we (a) develop new models of cooperation among academia, industry, and government, (b) continue the growth of international participation in cancer research (more keen minds to the task), and (c) convince the governments of the world, including that of the U.S., that an investment in minimizing the effects of cancer is as important as defending against other threats to the welfare and longevity of their citizens.
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PMID:Battling the hematological malignancies: the 200 years' war. 1830 57

Nitrogen-containing bisphosphonates (N-BPs) inhibit osteoclast-mediated bone resorption and are widely used for tumor-associated osteolysis. The mechanism of action of these drugs has not been completely clarified, but it has been observed that N-BPs may inhibit squalene synthase or farnesyl pyrophosphate synthase. Zoledronic acid (ZA) represents a novel N-BP which also has antitumor activity. To explore the effects of ZA on serum lipids, we studied 26 patients with smoldering myeloma at diagnosis. Sixteen patients were treated with ZA (4 mg) at baseline and at months 1, 2, 4, and 6. The remaining 10 served as controls. In all subjects, total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and C-terminal telopeptide of type I collagen (CTX) were measured at baseline and after 1, 3, and 6 months. In treated patients, we observed a progressive and significant reduction of TC, with a maximum decrease of 13% at 6 months. Moreover LDL-C decreased by 21% at 6 months, while no significant difference was appreciated in HDL-C and TGs. Also, the indexes of cardiovascular risk improved after ZA administration: TC/HDL-C ratio progressively decreased by 17% and HDL-C/LDL-C ratio increased by 36%, showing an effect that appears to be cumulative. In conclusion, ZA given intravenously at high doses in patients with smoldering myeloma seems to be able to modify the lipid profile with an improvement of atherosclerotic risk index.
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PMID:The effects of zoledronic acid on serum lipids in multiple myeloma patients. 1841 38

Bisphosphonates (BPs) are effective inhibitors of tumor-induced bone resorption. Recent studies have demonstrated that BPs inhibit growth, attachment and invasion of cancer cells in culture and promote apoptosis. The mechanisms responsible for the observed anti-tumor effects of BPs are beginning to be elucidated. Recently, we reported that nitrogen-containing bisphosphonates (N-BPs) induce formation of a novel ATP analog (ApppI) as a consequence of the inhibition of farnesyl diphosphate synthase in the mevalonate pathway. Similar to AppCp-type metabolites of non-N-BPs, ApppI is able to induce apoptosis. This study investigated BP-induced ATP analog formation and its effect on cancer cell growth. To evaluate zoledronic acid (a N-BP)-induced ApppI accumulation, inhibition of protein prenylation and clodronate (a non-N-BP) metabolism to AppCCl2p, MCF-7 and MDA-MB-436 breast cancer cells, MCF-10A nonmalignant breast cells, PC-3 prostate cancer cells, MG-63 osteosarcoma cells, RPMI-8226, and NCI-H929 myeloma cells were treated with 25 micromol/l zoledronic acid or 500 micromol/l clodronate for 24 h. The inhibition of cell growth by zoledronic acid and clodronate was studied in MCF-7, MDA-MB-436, and RPMI-8226 cells by exposing the cells with 1-100 micromol/l zoledronic acid or 10-2000 micromol/l clodronate for 72 h. Marked differences in zoledronic acid-induced ApppI formation and clodronate metabolism between the cancer cell lines were observed. The production of cytotoxic ATP analogs in tumor cells after BP treatment is likely to depend on the activity of enzymes, such as farnesyl diphosphate synthase or aminoacyl-tRNA synthetases, responsible for ATP analog formation. Additionally, the potency of clodronate to inhibit cancer cell growth corresponds to ATP analog formation.
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PMID:Bisphosphonate-induced ATP analog formation and its effect on inhibition of cancer cell growth. 1845 49


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