Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Taxanes have been shown to interact with anti-apoptotic proteins. In the present study we investigated whether the addition of taxane in combination with DNA damaging drugs can further enhance tumor shrinkage in cases with incomplete response to radiotherapy. Since the dose of docetaxel in combination with carboplatin is not known, the above hypothesis was tested in the context of a dose escalation phase I study. Twenty-eight patients with locally advanced chest or pelvic tumors, showing residual disease on CT scans performed 40 d following docetaxel radio-chemotherapy, were recruited in a dose escalation protocol of docetaxel/carboplatin supported with amifostine and GM-CSF. The starting dose of docetaxel was 40 mg/m2 every 2 weeks. Carboplatin dose was calculated using the Calvert formula and was escalated in cohorts of 4 patients (starting dose AUC2 every two weeks; AUC0.5 increments up to AUC3). Thereafter the docetaxel dose was increased to 50 and 60 mg/m2, while carboplatin was escalated (by AUC0.5 increments) starting from AUC3 and AUC4 respectively. Amifostine (600 mg/m2) was administered i.v. before carboplatin and GM-CSF (480 microg) was injected s.c. on days 5, 6 and 10, 11 of each cycle. Six cycles were given and response was assessed 2 weeks after the end of chemotherapy. None out of four patients treated in the 6th dose level cohort (50 mg/m2 of docetaxel and AUC4 of carboplatin every 2 weeks) showed any grade 2-4 hematologic toxicity. Mild non-hematologic toxicity such as neuropathy, leg edema, pleural effusion, pyrexia, alopecia grade 2 and hypersensitivity was observed in 4-12% of patients. Out of four patients treated in a 7th cohort (docetaxel 60 mg/m2 and carboplatin AUC4), one developed grade IV neutropenia and two developed grade 3 severe asthenia requiring treatment delay for 2 weeks. Out of 11 patients with PR following docetaxel radio-chemotherapy, 7 (63%) showed CR after docetaxel/carboplatin additional chemotherapy. Eight out of 17 patients with MR following docetaxel radio-chemotherapy showed PR (47%) and one showed CR (6%) after additional chemotherapy. High dose combined docetaxel (50 mg/m2) and carboplatin (AUC4) chemotherapy can be safely administered on a two-weekly basis if supported with amifostine and GM-CSF. Such an additional therapy may be important in patients with incomplete response after chemo-RT. Broad spectrum cytoprotection with amifostine and GM-CSF may also contribute to the reduction of incidence of neurosensory reactions and asthenia in patients treated with taxanes.
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PMID:Phase I/II dose escalation study of docetaxel and carboplatin combination supported with amifostine and GM-CSF in patients with incomplete response following docetaxel chemo-radiotherapy: additional chemotherapy enhances regression of residual cancer. 1087 20

Amifostine protects healthy tissues but not tumor cells from the damage induced by cytotoxic treatments, particularly ionizing radiations, alkylating and platinating agents. The clinical effectiveness of amifostine has been demonstrated by randomized trials in ovarian and head-and-neck cancer patients treated with chemotherapy with or without radiation therapy. The available pharmacoeconomic data confirm a favorable cost/utility ratio. The majority of non small cell lung cancer (NSCLC) patients receive radio and/or chemotherapy. A role for amifostine in these patients has been hypothesized, and some experiences performed. The aim of this paper is to outline the present role of amifostine in the treatment of NSCLC.
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PMID:The potential role of amifostine in the treatment of non small cell lung cancer. 1088 Aug 48

Clinical trials indicate that amifostine may confer protection on various normal tissues without attenuating anti-tumor response. When administered prior to chemotherapy or radiotherapy, it may provide a broad spectrum of cytoprotection including against alkylating drugs. The mechanism of protection resides in the metabolism at normal tissue site by membrane-bound alkaline phosphatase. Toxicity of this drug is moderate with hypotension, nausea and vomiting, and hypocalcemia being observed. We report a phase II study using amifostine as a protective drug against high-dose cyclophosphamide (HDCY) (7 g/m2), used to mobilize peripheral blood progenitor cells (PBPC) and to reduce tumor burden. We enrolled 29 patients, 22 (75. 9%) affected by aggressive and 7 (24.1%) by indolent non-Hodgkin's lymphoma (NHL), who were submitted to 58 infusions of amifostine and compared them with a historical group (33 patients) affected by aggressive NHL and treated with VACOP-B followed by HDCY. The most important results in favor of amifostine were the reduction of intensity of cardiac, pulmonary and hepatic toxicity, and a significant reduction of frequency and severity of mucositis (P = 0. 04). None of the 29 patients died in the protected group, while in the historical group 2/33 patients died because of cardiac or pulmonary toxicity and 2 patients stopped therapy due to toxicity. Amifostine did not prevent the aplastic phase following HDCY. PBPC collection and hematological recovery were adequate in both groups. The number of CFU-GM (colony-forming units-granulocyte/macrophage) colonies and mononuclear cells in the apheresis products was significantly higher in the amifostine group (P = 0.02 and 0.01, respectively). Side effects were mild and easily controlled. We conclude that amifostine protection should be useful in HDCY to protect normal tissues, with acceptable side effects.
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PMID:Amifostine (WR-2721), a cytoprotective agent during high-dose cyclophosphamide treatment of non-Hodgkin's lymphomas: a phase II study. 1088 Oct 54

We examined the ability of WR-1065, the biologically active aminothiol form of the clinically used drug amifostine (WR-2721, Ethyol), to protect cultures of two human glioblastoma cell lines of greatly differing radiosensitivity from the cytotoxic effects of gamma radiation. M059J cells are extremely radiosensitive compared to M059K cells (which were derived from the same tumor) and are defective in the DNA-dependent protein kinase (DNAPK)-mediated pathway for the repair of DSBs. In spite of their marked phenotypic differences, the two glioblastoma lines were protected equivalently ( approximately 1.8-fold) after a 30-min preirradiation treatment with 4 mM WR-1065. These findings are in agreement with earlier studies that showed no relationship between the ability of another aminothiol, cysteamine, to protect human tumor cells with differing abilities to repair DSBs and/or radiosensitivity. Thus it appears that differences in intrinsic radiosensitivity and ability to repair DSBs are not important general factors in the modulation of the radiosensitivity of human cells by aminothiols. Because of a previous report that the radiosensitive mutant rodent xrs5 cell line (which, like M059J, is defective in the DNAPK-mediated pathway for repairing DSBs) is unusually refractory to the radioprotective effects of WR-1065, we re-examined the ability of WR-1065 to protect these cells. In contrast to the earlier studies, both the wild-type and mutant rodent lines were protected extensively by WR-1065. This discrepancy might be related to some unknown factor, such as differences in chromatin organization among xrs5 subclones that arise during their karyotypic evolution, possibly leading to altered DNA-drug associations.
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PMID:Protection of human tumor cells of differing radiosensitivity by WR-1065. 1093 87

Effective radiotherapy for patients with cancer should include maximal tumor cell killing with minimal injury to normal tissue. Radiation doses that can be delivered, without causing severe damage to surrounding normal tissues, can be insufficient to eradicate a tumor. Agents have been developed to protect normal tissue from the toxicities of radiation. The aminothiol amifostine (Ethyol) is the subject of extensive research as a protector. Several studies have demonstrated that amifostine protects normal tissues from both acute and late radiation damage without protecting the tumor. This article reviews the physicochemical basis of radiation therapy on biologic tissues and the mechanisms responsible for the protective effects of amifostine. The increasing body of biochemical, preclinical, and clinical data can justify the use of protectors such as amifostine with radiotherapy to provide improved therapeutic efficacy and quality of life for the patient. This article will review the current understanding of the nature of toxicity resulting from radiation therapy and the benefits that can be derived from using protection to increase the tolerance of normal tissue to radiation damage.
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PMID:The role of amifostine as a radioprotector. 1170 62

Intrinsic radioresistance, tumor hypoxia and ability of cancer cells to undergo rapid repopulation during radiotherapy are associated with failure of radiotherapy. Tumors with low alpha/beta-ratio values or hypoxic tumors unable to undergo re-oxygenation, are unlikely to be eradicated with standard radiotherapy. Although the therapeutic efficacy of accelerated regimens based on low-dose per fraction may be high since they minimize the adverse role of rapid tumor repopulation, the cellular compartment with low alpha/beta-ratio values (i.e. hypoxic cells) remains a limiting factor. Accelerated hypofractionation, which may be more effective in such tumors, cannot be safely applied unless normal tissues are protected. In the present study we assessed the feasibility of hypofractionated and accelerated radiotherapy supported by cytoprotection (HypoARC) with high dose daily amifostine. Fifteen breast cancer patients with locally advanced disease entered radiation-dose escalation protocoL Twelve consecutive fractions of 3.5-4Gy (5 fractions/week) were given to the breast/chest wall, supraclavicular and axillary area, within 17 days. A high dose of amifostine, at 1,000 mg flat dose, was given 20 minutes before each radiotherapy fraction. Amifostine administration was well- tolerated with minor side-effects (vomiting in 6 out of 15 and hypotention in 2 out of 15 patients). Radiation induced acute skin toxicity was negligible (grade 3 in 1 out of 15 patients). Ten out of 15 patients survived more than 12 months and 7 out of 15 more than 18 months following HypoARC. None of these patients showed any signs of late sequellae, such as lung and myoskeletal fibrosis, or brachial plexopathy. Complete and partial responses were obtained in 11 out of 15 (73%) and in 4 out of 15 (27%) patients, respectively. High dose daily amifostine during hypofractionated radiotherapy is feasible. HypoARC regimen is well-tolerated, effective and has minimal acute and late toxicity to normal breast, chest and axillary tissues.
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PMID:High dose daily amifostine and hypofractionated intensively accelerated radiotherapy for locally advanced breast cancer. A phase I/II study and report on early and late sequellae. 1171 96

Amifostine was investigated for its ability to inhibit spontaneous metastases formation using the well-characterized murine sarcoma, Sa-NH. Amifostine was administered intraperitoneally at a dose of 50 mg/kg every other day for 6 days to C3Hf/Kam mice until tumors reached an average size of 8-8.5 mm in diameter. Amifostine was again administered immediately after surgical removal of the tumor-bearing limbs by amputation, and then once more 2 days later. Twenty-one days later, animals were evaluated for the presence of spontaneously developed pulmonary metastases. Nontumor-bearing control animals were sham treated using the same dosing and surgery schedules. Treatment with amifostine appeared to slightly delay tumor growth, that is, 13 vs. 12 days for tumors to reach an average diameter of 8 mm. Amifostine reduced both the incidence of pulmonary metastases formed in experimental animals from 77% to 57% (p < 0.05), and their average number per animal from 12.8 +/- 5.4 (SEM) to 2.9 +/- 1.1 (SEM). The effect of amifostine exposure on serum levels of the angiogenesis inhibitor angiostatin was also determined using Western blot analysis. Consistent with the antimetastatic effect, exposure of animals to 50 mg/kg of amifostine resulted in a 4-fold enhanced serum level of angiostatin above control levels. This phenomenon occurred in tumor-bearing and nontumor-bearing animals. The effects of amifostine on matrix metalloproteinase (MMP) enzymatic activity was also determined using gelatin zymography. Conditioned growth medium collected from Sa-NH cells grown to confluency was exposed to various concentrations of SH, i.e., 2-[(aminopropyl)amino]ethane-thiol (WR-1065), the active thiol form of amifostine, for either 30 min or 18 hr. WR-1065, as a function of increasing dose and time, inhibited the enzymatic activities of MMP-2 and MMP-9. At a concentration and time of exposure likely to be achieved in vivo, that is, 40 microM and 30 min, MMP-2 and MMP-9 activities were reduced to between 30% and 40% of control values. Consistent with these affects, WR-1065 was also found to be effective in inhibiting the ability of Sa-NH cells to migrate through Matrigel membranes. After an 18-hr exposure under in vitro conditions, WR-1065 at concentrations of 4, 40 and 400 microM, and 4 mM, inhibited Sa-NH migration to 11%, 44%, 81% and 97% of control values, respectively. The abilities of amifostine and its active thiol WR-1065 to stimulate angiostatin production in mice, and to inhibit the MMP enzymatic activities and invasion ability of Sa-NH cells under in vitro conditions, are consistent with the observed antimetastatic effects exhibited against Sa-NH tumors growing in vivo.
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PMID:Inhibition of spontaneous metastases formation by amifostine. 1177 55

The authors discuss the results of 3 studies of their group reflecting the possible role of amifostine in simultaneous radiochemotherapy (RCT) of advanced head and neck cancer. In a controlled phase II trial (1995 through 1996), 39 patients were included in this pilot investigation. A control group (n = 14) received simultaneous RCT of the head and neck region with an irradiation dose of 60 Gy and 2 cycles of carboplatin (700 mg/m(2) cumulative dose). Twenty-five patients received the same basic therapy and an additional 500-mg dose of amifostine before each chemotherapy. Amifostine was administered less than 45 minutes before the end of radiotherapy. The authors observed a dramatic reduction of typical radiotherapy-associated toxicities (mucositis, xerostomia, loss of taste, dysphagia). The hematologic side effects (leukocytopenia, anemia, thrombocytopenia) also were decreased significantly. The overall survival rate and locoregional control of both groups were comparable after 12 months. In a controlled intensification trial (1997 through 1999), the authors included 76 consecutive patients (69 men, 7 women) with pharyngeal cancer (oropharynx, n = 33; hypopharynx, n = 43). The tumors were characterized as unresectable and locally advanced without distant metastasis. All patients received a conventional radiotherapy (2-Gy single dose, daily fractionation) up to doses of 60 Gy and an additional 10 Gy as a boost in the tumor-infiltrated region. A dose of carboplatin, 70 mg/m(2), was given to a group of 45 patients on days 1 through 5 and 29 through 33 of radiotherapy (RCT arm). The resulting cumulative dose was 700 mg/m(2). A group of 31 patients (RCTintens arm) received the same dose of carboplatin on days 1 through 5, 22 through 26, and 43 through 47 or 1 through 5, 15 through 19, 29 through 33, and 43 through 47 of radiotherapy (cumulative dose 1.05 to 1.40 mg/m(2)). All patients received 500 mg of amifostine before each carboplatin administration. If the tumor volume was less than 20 cm(3), we observed an increased 1-year overall survival rate (91% v 71%) and time to progression (17 months v 10 months). If the tumor volume was greater than 20 cm(3), we observed comparable treatment results in both groups (1-year survival rate, 60% v 61%; time to progression, 13 months v 12 months). In a long-term follow-up investigation (1999 through 2000), 531 patients (89 women, 442 men) were analyzed according to their toxicities during regular follow-up investigations at our outpatient facility. All patients were treated by surgery or radio(chemo)therapy because of an advanced head and neck cancer. A total of 218 of 531 patients received the antineoplastic therapy without cytoprotection. An additional 313 patients received their RCT combined with amifostine administration before administration of the radiosensitizer. A significant influence of cytoprotection was registered in the following toxicities: xerostomia, fibrosis, loss of taste, and dysphagia. No impact was seen on the development of interstitial lymph edema and esophageal stenosis. Amifostine could be integrated in simultaneous radiochemotherapy of advanced head and neck cancer patients. The authors favor the administration of amifostine before chemotherapeutics alone. Selective cytoprotection could decrease the main acute toxicities (mucositis, xerostomia, dysphagia) as well as late side effects (xerostomia, loss of taste, fibrosis) of this form of combined treatment. The enhanced therapeutic index may be changed into a prognostic benefit for selected patients with unresectable tumors, if the volume is smaller than 20 cm(3).
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PMID:Amifostine in simultaneous radiochemotherapy of advanced head and neck cancer. 1191 77

The degree of xerostomia has been reported to depend on the radiation dose and the salivary gland volume irradiated. Sparing salivary function can be achieved by reducing radiation dose to the salivary glands or using a radiation protector, such as amifostine (Ethyol). In this report, the author reviews clinical experiences in intensity-modulated radiation therapy (IMRT) for head and neck cancer. In experiences, the dosimetric advantage of IMRT did translate into significant reduction of late salivary toxicity in patients with oropharyngeal carcinoma. The author has found no adverse impact on tumor control and disease-free survival in patients treated with IMRT. Further, when studying the dose response of parotid gland after irradiation, it was found that the stimulated saliva flow 6 months after IMRT treatment reduced at approximately 4% per Gy exponentially of the mean parotid dose. The authors also review existing clinical data on the combination of amifostine and radiation and the potential therapeutic gain in combining IMRT with amifostine.
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PMID:Protection of salivary function by intensity-modulated radiation therapy in patients with head and neck cancer. 1191 80

The ultimate goal of any strategy in oncology is to enhance the therapeutic ratio, defined as tumor cell kill divided by normal tissue injury. Whereas most trials focus on intensifying therapy, this often increases toxicity so that there is no overall gain in the therapeutic ratio. Radiation Therapy Oncology Group (RTOG) trial 98-01, a phase III study testing the ability of a radioprotector (Amifostine [Ethyol, WR-2721]) to reduce the toxicity of an intensive chemoradiation regimen for locally advanced non-small cell lung cancer (NSCLC), is unique in that it addresses both "sides" of this equation. During the 1990s, thoracic radiotherapy (RT) combined with chemotherapy was accepted as a "new" gold standard for patients with good performance status locally advanced/inoperable NSCLC. This paradigm shift away from RT alone has raised several key questions: What is the optimal method of integrating chemotherapy and RT? Equally importantly, how can the toxicity of combined modality strategies be reduced? This article will review the background underlying RTOG 98-01, a trial exploring the potential role of amifostine in NSCLC.
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PMID:Exploring the role of the radioprotector amifostine in locally advanced non-small cell lung cancer: Radiation Therapy Oncology Group trial 98-01. 1191 83


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