Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dolastatin-10 is a natural, cytotoxic peptide with microtubule-inhibitory and apoptotic effects. It has demonstrated in vitro and in vivo efficacy in the DU-145 human prostate cancer model. A Phase II clinical trial was designed in patients with hormone-refractory prostate cancer. Dolastatin-10 was administered at a dose of 400 microg/m2 i.v. every 3 weeks. Dose escalation to 450 microg/m2 was permitted. Toxicity evaluation was conducted every 2 weeks, and assessment of response was done at the end of every two cycles. Sixteen patients were enrolled between October 1998 to December 1999. The median age was 71 years (range, 59-79 years). Median prostate-specific antigen value was 108 ng/ml (range, 15.3-1672 ng/ml). Of the 15 eligible patients, 7 were Caucasian and 8 were African-American. Eight patients had bone-only metastases, and seven had measurable disease with or without bone metastases. A total of 56 cycles have been administered. Only 2 patients required dose adjustment because of toxicity, and in 5 patients, dose escalation was feasible to 450 microg/m2. The major toxicities observed were grade 3 and 4 neutropenia in 8 patients and grade 3 neuropathy in 1 patient. All 15 patients are evaluable for response. Three patients demonstrated stable disease; 2 of these had bone disease, and 1 had nodal metastasis. All others had disease progression. Dolastatin-10 is very well tolerated in this elderly, pretreated population but lacks significant clinical activity as a single agent.
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PMID:Phase II study of dolastatin-10 in patients with hormone-refractory metastatic prostate adenocarcinoma. 1110 33

The presence of skeletal metastases in patients suffering from cancer leads to a variety of clinical complications. Bisphosphonates are a class of drugs with a potent bone resorption inhibition activity that have found increasing utility in treating and managing patients with metastatic bone disease. Several clinical trials have demonstrated that bisphosphonates have clinical value in the treatment and management of skeletal metastases derived from advanced prostate cancer. Currently, the mechanism(s) through which bisphosphonates exert their activity is only beginning to be understood. We have studied the effects of bisphosphonate treatment on the growth of prostate cancer cell lines in vitro. Treatment of PC3, DU145, and LNCaP cells with pamidronate or zoledronate significantly reduced the growth of all three cell lines. Using flow cytometry, pamidronate treatment (100 microM) was shown to induce significant amounts of cell death in all three cell lines studied. In contrast, treatment with zoledronate (100 microM) did not induce cell death, instead exerting dramatic effects on cell proliferation, as evidenced by a major increase in cells present in the G0-G1 and S phase. Although both drugs reduced prostate cancer cell growth in the presence of serum, zoledronate was more potent under these conditions, disrupting growth at doses as low as 25 microM in the presence of 5% fetal bovine serum. These results raise the intriguing possibility that the observed clinical utility of bisphosphonates in managing skeletal metastases may in part derive from direct inhibition of prostate cancer cell growth in the bone microenvironment.
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PMID:Bisphosphonate treatment inhibits the growth of prostate cancer cells. 1128 37

Preclinical studies with zoledronic acid (Zometa; Novartis Pharmaceuticals Corp, East Hanover, NJ) have shown its potential in malignant bone disease. Clinical studies in the treatment of hypercalcemia of malignancy have been completed, as have phase I and II trials in patients with cancer and pre-existing bone metastases. Three randomized, double-blind, controlled phase III trials are ongoing to establish the efficacy and safety of zoledronic acid in the treatment of osteolytic and osteoblastic bone metastases. In one study, 4 mg zoledronic acid is compared with the standard therapy, 90 mg pamidronate, in treatment of osteolytic lesions in patients with breast cancer and multiple myeloma. Two other studies, one in patients with prostate cancer and bone metastases and another in patients with non-small cell lung cancer and other tumor types, are placebo-controlled. The primary end point in all three studies is the frequency of skeletal complications resulting from bone metastases. Adjuvant trials that assess the ability of zoledronic acid to prevent or reduce the incidence of bone metastases in patients at high risk for future skeletal metastasis are also planned or ongoing. The rationale and design of these ongoing and planned studies is discussed.
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PMID:The role of zoledronic acid in cancer: clinical studies in the treatment and prevention of bone metastases. 1134 60

Metastatic bone disease is an important clinical problem which has proven difficult to study because of a lack of noninvasive investigative modalities. Here we show that dual-energy X-ray absorptiometry (DXA) scanning provides clinically useful information about the status of metastatic bone lesions in cancer patients undergoing palliative treatment. In the study group of 21 patients, a significant increase in metastatic bone mineral density (BMD) was confirmed in prostate (n = 14) relative to breast (n = 7) cancer patients. With respect to the prostate cancer cohort, further increases in lesional BMD were evident in all evaluable patients in whom biochemical progression occurred; conversely, lesional BMD declined in patients who had a partial response to therapy. BMD of uninvolved bone decreased with all types of androgen-deprivation therapy regardless of whether patients responded or relapsed. We conclude that BMD changes in both lesional and uninvolved bone are readily detectable in metastatic prostate cancer, and propose that DXA scanning represents a promising new approach to monitoring the natural history and therapeutic course of this disease.
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PMID:Dual X-ray absorptiometry detects disease- and treatment-related alterations of bone density in prostate cancer patients. 1146 70

Improved understanding of the pathophysiology of prostate cancer-induced metabolic bone disease implies that bisphosphonates may have a role in the treatment of this disorder. Although prostate cancer cells stimulate osteoblasts, resulting in a marked increase in bone volume and the classic radiologic aspect of sclerotic metastases, accelerated bone resorption has been reported by histomorphometric and biochemical studies. The significant relationship between the biochemical parameters of bone resorption and formation suggests a coupling between these two processes in metastatic prostate cancer. Several studies have demonstrated that administration of bisphosphonates is one of the most cost-effective palliative treatments for patients with prostate carcinoma and bone metastases, both as first-line and long-term therapy. With appropriate doses, a large proportion of patients can be maintained free of bone pain until death. Studies of the efficacy of lower doses to prevent skeletal morbidity in patients without metastases or with asymptomatic bone lesions are warranted.
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PMID:The use of bisphosphonates in the management of bone metastatic prostate cancer. 1208 96

Bisphosphonates (BPs) are potent inhibitors of osteoclast-mediated bone resorption, and it is well accepted that tumor cells in bone, especially breast cancer and myeloma cells, can stimulate osteoclast formation and activity leading to the release of growth factors or cytokines, which will further stimulate cancer cells' growth and their secretion of osteolytic factors. BPs are now the standard treatment for cancer hypercalcemia, for which a dose of 90 mg of pamidronate or 1500 mg of clodronate is recommended; the former compound is more potent and has a longer lasting effect. Repeated pamidronate infusions exert clinically relevant analgesic effects in more than half of patients with metastatic bone pain. Recent data suggest that non-responding patients should perhaps be treated with higher doses. The optimal dose actually remains to be defined, especially as it is thought that it is probably a function of the disease stage. Regular pamidronate infusions can also achieve a partial objective response according to conventional UICC criteria and they can almost double the objective response rate to chemotherapy. Lifelong administration of oral clodronate to patients with breast cancer metastatic to bone reduces the frequency of morbid skeletal events by more than one-fourth. Two double-blind randomized placebo-controlled trials comparing monthly 90 mg pamidronate infusions to placebo infusions for 1-2 years in addition to hormone or chemotherapy in patients with at least one lytic bone metastasis have shown that the mean skeletal morbidity rate could be reduced by 30-40%. The results obtained with intravenous BPs are generally viewed as better than those obtained with oral clodronate. However, preference can be given to the oral route when BPs are started early in the process of metastatic bone disease in a patient receiving hormone therapy. According to the recently published ASCO guidelines, pamidronate 90 mg i.v. delivered over 2 h every 3-4 weeks can be recommended in patients with metastatic breast cancer who have imaging evidence of lytic destruction of bone and who are concurrently receiving systemic therapy with hormonal therapy or chemotherapy. Furthermore, the ASCO Panel considered it "reasonable" to start i.v. BPs in women with localized pain whose bone scans were abnormal and plain radiographs normal, but not when an abnormal bone scan is asymptomatic. The pertinence of these criteria is discussed below. Because BPs are providing supportive care, reducing the rate of skeletal morbidity but evidently not abolishing it, the criteria for stopping their administration have to be different from those used for classic antineoplastic drugs, and they should not be stopped when metastatic bone disease is progressing. However, criteria to determine whether and for how long an individual patient benefits from their administration are lacking. New biochemical markers of bone resorption might help identify those patients continuing to benefit from therapy. Even better results have been achieved in patients with multiple myeloma, and the general consensus is that BPs should be started as soon as the diagnosis of lytic disease is made in myeloma patients. On the other hand, data are scanty in prostate cancer, but large-scale trials with potent BPs are ongoing or planned in such patients. Similar results to those achieved with pamidronate have been obtained with monthly 6-mg infusions of the newer BP ibandronate in patients with breast cancer metastatic to bone. The tolerance of ibandronate could be better, and the drug has the potential to be administered as a 15- to 30-min infusion. Zoledronate can also be administered safely as a 15-min 4-mg infusion, and large scale phase III trials have just been completed. These newer BPs will simplify the current therapeutic schemes and improve the cost-effectiveness ratio; they also have the potential to improve the therapeutic efficacy, at least in patients with an aggressive osteolytic disease or when given as adjuvant therapy. For that matter, initial data with clodronate indicate that they have the potential to prevent the development of bone metastases, but the use of BPs in the adjuvant setting must still be viewed as experimental.
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PMID:Bisphosphonates for cancer patients: why, how, and when? 1213 23

Bisphosphonates are stable analogues of pyrophosphate (PPi), an endogenous regulator of bone mineralisation. A number of placebo-controlled trials have demonstrated their positive impact on skeletal-related events (SRE) that occur as a consequence of metastatic or myelomatous bone disease. Based upon their chemical structure bisphosphonates can be classified into nitrogen-containing bisphosphonates, (N-bisphosphonates) (for example zoledronate and pamidronate) and non-nitrogen containing (for example, clodronate and etidronate), which more closely resemble PPi. Clinical trials investigating bisphosphonates in the preventative setting have shown bisphosphonates to not only delay occurrence of bone metastases in certain cancers, but in one trial, occurrence of non-osseous lesions was delayed, and survival was prolonged. Other trials however have shown the opposite. Likewise, in animal models of cancer and metastases, conflicting results have been obtained. In vitro work has concentrated on bisphosphonates direct action upon tumour cells and has found a variety of anti-tumour effects such as apoptosis induction, inhibition of cell growth, inhibition of invasive behaviour and inhibition of angiogenic factors. Furthermore it would appear that bisphosphonates have the potential to enhance anti-tumour activity of known cytotoxic drugs. Ongoing research aims to assess this further, in addition to determining more precisely the role of adjuvant bisphosphonates in cancers such as breast and prostate cancer.
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PMID:The anti-tumour activity of bisphosphonates. 1247 Sep 81

Prostate cancer is a common disease among older men. Androgen suppression by either orchiectomy or administration of luteinising hormone-releasing hormone (LHRH) analogues is the mainstay of treatment. Since the use of prostate-specific antigen (PSA) serum testing has become widespread, however, the timing of endocrine therapy has expanded considerably to include patients with limited involvement of extraprostatic sites and patients presenting an isolated elevation of PSA after radical treatments. These patients are expected to be treated for a long time, since they have a rather low risk of disease progression and there is no recommended time limit for LHRH analogue therapy. The long-term adverse effects of androgen deprivation therapy, therefore, deserve more attention than they have received in the past. Osteoporosis represents a special concern for men with prostate cancer receiving androgen deprivation therapy. The rate of bone loss in these men seems to markedly exceed that associated with menopause in women, and fractures occur more frequently than in the healthy elderly male population. Serial bone mineral density (BMD) evaluation could allow the detection of patients with prostate cancer who are at greater risk of osteoporosis and adverse skeletal events after androgen deprivation therapy, such as patients already osteopenic or osteoporotic at baseline and men with rapid bone loss during treatment. BMD evaluated during treatment could also be a potential surrogate parameter of antiosteoporotic therapeutic efficacy. Treatment of bone loss induced by androgen deprivation comprises general prevention measures, antiosteoporotic drugs and the use of alternative endocrine therapies. Optimising lifestyle and diet is important, although it cannot completely prevent bone loss. Patients with nonsevere bone disease may benefit from calcium and vitamin D supplements. Men who are osteoporotic before androgen deprivation or men becoming osteoporotic during treatment and/or experiencing adverse skeletal events may also require bisphosphonates. The effectiveness of these drugs in preventing fractures has been shown in a single randomised study involving patients with osteoporosis, but it has not yet been established in a prostatic cancer population without bone metastases given androgen deprivation therapy. Different forms of endocrine therapy such as low-dose estrogens, antiandrogens and intermittent androgen ablation are under investigation. They could offer the advantage of avoiding (or limiting) treatment-related bone loss. In our opinion, however, the data available so far are not robust enough to recommend these alternative endocrine therapies instead of standard androgen deprivation in routine clinical practice.
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PMID:Background to and management of treatment-related bone loss in prostate cancer. 1249 66

Bisphosphonates are now well established as successful agents for the prevention and treatment of postmenopausal osteoporosis, corticosteroid-induced bone loss and Paget's disease. Bisphosphonates have also recently become important in the management of cancer-induced bone disease, and they now have a widely recognized role for patients with multiple myeloma and bone metastases secondary to breast cancer and prostate cancer. Recent studies suggest that, besides the strong antiosteoclastic activity, the efficacy of such compounds in the oncological setting could also be due also to direct antitumor effect, exerted at different levels. Here, after a brief analysis of the chemical structure, we will review the antineoplastic and biological properties of bisphosphonates. We will start from well estabilished mechanisms of action and go on to discuss the latest evidence and hypotheses. In particular, we will review the antiresorptive properties in malignant osteolysis and the recent evidence of a direct antitumor effect. Furthermore, this review will analyze the influence of bisphosphonates on cancer growth factor release, their effect on cancer cell adhesion, invasion and viability, the proapoptotic potential on cancer cells, the antiangiogenic effect, and, finally, the immunomodulating properties of bisphosphonates on the gammadelta T cell population.
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PMID:The antineoplastic role of bisphosphonates: from basic research to clinical evidence. 1450 45

Many advanced cancers, particularly breast cancer and prostate cancer, metastasize to the bone, resulting in painful lesions and skeletal complications. Intravenous bisphosphonate therapy is an important component of palliative care for patients with bone metastases, and pamidronate has been the standard of care for patients with breast cancer and multiple myeloma since 1996. However, zoledronic acid is the first bisphosphonate shown to significantly reduce skeletal morbidity in patients with a wide range of primary tumor types. Zoledronic acid has demonstrated efficacy in the management of hypercalcemia and metastatic bone disease. In phase III studies involving more than 3000 patients with multiple myeloma, breast cancer, prostate cancer, lung cancer, and other cancers, 4 mg zoledronic acid demonstrated consistent efficacy across a range of clinical end-points, and was safe and well tolerated when infused over 15 min. Based on these studies, zoledronic acid appears to be active in patients with bone metastases irrespective of tumor type, and should be considered as the standard of care for the treatment of bone metastases.
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PMID:Proven efficacy of zoledronic acid in the treatment of bone metastases in patients with breast cancer and other malignancies. 1465 40


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