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)

A prospective randomized study was conducted to determine whether amifostine (Ethyol) reduces the rate of severe esophagitis and hematologic and pulmonary toxicity associated with chemoradiation or improves control of non-small cell lung cancer (NSCLC). Sixty patients with inoperable stage II or III NSCLC were treated with concurrent chemoradiotherapy. Both groups received thoracic radiation therapy (TRT) with 1.2 Gy/fraction, 2 fraction per day, 5 days per week for a total dose 69.6 Gy. All patients received oral etoposide (VP-16), 50 mg Bid, 30 minutes before TRT beginning day 1 for 10 days, repeated on day 29, and cisplatin 50 mg/m(2) intravenously on days 1, 8, 29, and 36. Patients in the study group received amifostine, 500 mg intravenously, twice weekly before chemoradiation (arm 1); patients in the control group received chemoradiation without amifostine (arm 2). Patient and tumor characteristics were distributed equally in both groups. Of the 60 patients enrolled, 53 were evaluable (27 in arm 1, 26 in arm 2) with a median follow-up of 6 months. Median survival times were 26 months for arm 1 and 15 months for arm 2, not statistically significantly different. Morphine intake to reduce severe esophagitis was significantly lower in arm 1 (2 of 27, 7.4%) than arm 2 (8 of 26, 31%; P =.03). Acute pneumonitis was significantly lower in arm 1 (1 of 27, 3.7%) than in arm 2 (6 of 26, 23%; P =.037). Hypotension (20 mm Hg decrease from baseline blood pressure) was significantly more frequent in arm 1 (19 of 27, 70%) than arm 2 (1 of 26, 3.8%; P =.0001). Only 1 patient discontinued treatment because of hypotension. These preliminary results showed that amifostine significantly reduced acute severe esophagitis and pneumonitis. Further observation is required to assess long-term efficacy.
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PMID:Randomized phase III study of chemoradiation with or without amifostine for patients with favorable performance status inoperable stage II-III non-small cell lung cancer: preliminary results. 1191 84

Amifostine (Ethyol), an inorganic thiophosphate, is a selective broad-spectrum cytoprotector of normal tissues that provides cytoprotection against ionizing radiation and chemotherapeutic agents, thus preserving the efficacy of radiotherapy and chemotherapy. This review summarizes the preclinical data and clinical experience with amifostine, and provides insight into future clinical directions. Amifostine, an inactive pro-drug, is transformed to an active thiol after dephosphorylation by alkaline phosphatase found in the normal endothelium. The absence of alkaline phosphatase in the tumoral endothelium and stromal components, and the hypovascularity and acidity of the tumor environment, may explain its cytoprotective selectivity. The cytoprotective mechanism of amifostine is complicated, involving free radical scavenging, DNA protection and repair acceleration, and induction of cellular hypoxia. Intravenous administration of amifostine 740-900 mg/m(2) before chemotherapy and 250-350 mg/m(2) before each radiotherapy fraction are widely used regimens. The US Food and Drug Administration has approved the use of amifostine as a cytoprotector for cisplatin chemotherapy and for radiation-induced xerostomia. Ongoing trials are being conducted to determine the efficacy of amifostine in reducing radiation-induced mucositis and other toxicities. Novel schedules and routes of administration are under investigation, and may further simplify the use of amifostine and considerably broaden its applications.
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PMID:Amifostine in clinical oncology: current use and future applications. 1198 63

Dermatomyositis is associated with malignancy in approximately 20-25% of cases. The most common associated cancers are ovarian, lung, pancreatic, stomach, colon and non-Hodgkin's lymphoma. Nasopharyngeal cancer is not common in the Caucasian population; however, there is a much higher incidence in Asian patients. Radiotherapy is the mainstay of treatment for early nasopharyngeal cancer, but combination chemoradiotherapy is becoming more common for patients with advanced disease since the Intergroup trial 0099 demonstrated improved progression-free survival and overall survival for chemoradiotherapy. Increasingly, the cytotoxic agent amifostine is being used prior to radiotherapy in an attempt to decrease associated morbidities. Amifostine has been found to significantly decrease acute and chronic xerostomia but not mucositis. It appears to be selectively protective to salivary glands and kidneys without being tumor protective. The most common side effects associated with amifostine are nausea, vomiting, hypotension, hypocalcemia and allergic reactions. We describe the case of a man with dermatomyositis and stage IV nasopharyngeal cancer treated with chemoradiotherapy and s.c. amifostine. The patient suffered a life-threatening anaphylactoid reaction to amifostine.
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PMID:Life-threatening anaphylactoid reaction to amifostine used with concurrent chemoradiotherapy for nasopharyngeal cancer in a patient with dermatomyositis: a case report with literature review. 1198 77

Nephrotoxicity is observed in 30% of patient's treated with chemotherapy schedules based on cisplatin analogues. Ethyol (amiphostin) was used as a protectant of kidney in 3 paediatric patients with neoplastic disease. Two patients suffered from Wilms tumour. One of them, a 5 month old boy presented with agenesis of the right kidney and stage II tumour in the left kidney. Bilateral Wilms tumour was recognised in a 6 year old girl. In both cases glomerular filtration was diminished. The third patient was a girl aged 5 who had isolated relapse of neuroblastoma in the central nervous system. Primary treatment caused nephrotoxic complications such as Fanconi syndrome and diminished glomerular filtration (66 ml/min). In these 3 cases Ethyol was used every lime before analogues of cisplatin were given. Tolerance and the effect of this protectant were good.
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PMID:[Application of Ethyol during chemotherapy in patients with impaired kidney function. Description of three cases]. 1200 47

The objective of this study was to assess the radioprotective effects of amifostine in the rat model of radiation-induced lung injury using fractionated doses of radiation, to determine whether amifostine given before irradiation protects tumor from radiation cytotoxicity, and to determine whether changes in plasma levels of transforming growth factor (TGF)-beta correlate with radioprotective effect of amifostine. R3230 AC mammary adenocarcinoma was transplanted on the right posterior chest wall of female Fisher-344 rats. Both tumor-bearing and non-tumor-bearing animals were irradiated to the tumor or right lung using 4 MV photons and fractionated dose of 35 Gy/5 fractions/5 days. Animals with tumors and those without were randomized into 4 groups, respectively (8 to 10 rats per group), to receive (1) radiation alone; (2) radiation + amifostine; (3) amifostine alone; (4) sham radiation. Amifostine (150 mg/kg) was given intraperitoneally 30 minutes before each fraction of irradiation. The tumor size was measured twice a week. Breathing rate was assessed every 2 weeks. TGF-beta levels in plasma were assessed monthly after treatment. Six months after irradiation, animals were euthanized and lung tissue was processed for hydroxyproline content analysis. A significant increase in breathing frequency started 9 weeks after irradiation in animals that received radiation only. In the radiation + amifostine group, there was both a delay and a significantly lower peak in breathing frequency (P < .001). Hydroxyproline content was higher in the radiation-alone group than in rats given amifostine prior to radiation (P < .05). The TGF-beta levels in plasma showed an increase from 1 to 3 months after radiation, peaking at 2 months in the rats with (2.80 +/- 0.23) or without (5.32 +/- 1.21) amifostine compared to sham irradiation. TGF-beta levels were significantly lower at 1 to 3 months in rats receiving amifostine plus radiation versus those receiving radiation alone. Tumor growth delay and regrowth rate after radiation were not different between radiation-alone and radiation + amifostine groups. This study confirms the protective effect of amifostine in reducing radiation-induced pulmonary toxicity. No tumor protection was demonstrated after fractionated radiotherapy. The reduction in pulmonary injury with amifostine in paralleling lower plasma levels of TGF-beta, suggesting that monitoring plasma levels of this cytokine may reflect the efficacy of an intervention aimed at preventing radiation-induced lung injury.
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PMID:Assessment of the protective effect of amifostine on radiation-induced pulmonary toxicity. 1239 50

The use of chemical radioprotectors represents an obvious strategy to improve the therapeutic index in radiotherapy. Amofostine (WR-2721) has recently been approved for use in head and neck cancer to protect against radiation-induced xerostomia. Currently, the question has arisen whether amifostine could be used for radioprotection in broader terms. Amifostine may have the potential to enable intensified treatment by ameliorating mucosal reactions that are often a limiting factor in accelerated fractionation or concomitant chemoradiation. However, it has as yet not been clarified whether sufficient amifostine to reduce mucositis can be administered before each radiation fraction without causing unacceptable toxicity. Also, the optimal dosage and schedule of amifostine in chemoradiation combinations have not yet been established. The major concern related to radioprotectiors is the potential hazard of collateral tumor protection. A number of clinical studies have concluded that amifostine does not reduce antitumor efficacy. However, not even the largest study conducted, with over 300 patients, has sufficient statistical power to detect a clinically significant reduction in tumor control rate. To put this issue ultimately to a rest, a clinical trial with a sufficient accrual to definitely rule out a tumor protective effect of amifostine needs to be conducted. Substances reducing radiation-induced toxicity by modulating the biological response to radiation injury may represent an alternative concept in radioprotection. However, such agents are still at a developmental stage.
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PMID:Chemical radioprotection: a critical review of amifostine as a cytoprotector in radiotherapy. 1252 Apr 65

Amifostine (WR-2721) is a well-known radioprotective drug, selective for normal cells. The purpose of the present study was to define whether amifostine protects the vascular network from the effects of X-rays. We used the in vivo system of chicken embryo chorioallantoic membrane (CAM) as a model of angiogenesis. Amifostine reversed the early X-rays- induced decrease in the number of CAM blood vessels and reversed the early radiation-induced apoptosis of CAM cells. It also inhibited the increase in tyrosine nitration of actin and a-tubulin, which was observed 6 hours after CAM irradiation, when there was a significant decrease in non-protein SH groups. Furthermore, C6 rat glioma cells were inoculated on CAM and tumor growth, as well as tumor-induced angiogenesis, was estimated on haematoxylin-eosin-stained paraffin sections. Amifostine inhibited the post irradiation increase of C6 tumor-induced angiogenesis. These data suggest that amifostine protects CAM cells and blood vessels from the effects of X-rays, through mechanisms that do not depend solely on its free radical scavenging properties.
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PMID:Amifostine protects blood vessels from the effects of ionizing radiation. 1253 3

Differentiated thyroid cancer can be effectively treated with high-dose 131I and the other head and neck cancer can also be effectively treated with extra-radiotherapy, but these treatments often result in a reduction in salivary gland function, causing xerostomia. Collectively, these effects can lead to severe secondary complications, including difficulty in speaking and swallowing, decreasing appetite even affecting nutrition and sleep. Amifostine, an analog of cysteamine, is a phosphorlyated aminothiol prodrug and its active metabolite, WR-1065 etc, can selectively protect normal tissues from the cytotoxic effects of drugs and/or radiation while preserve antitumor effects. Many studies have demonstrated that amifostine protects normal tissues from both acute and late extra-radiation damage without protecting the tumor. It has been approved by FDA to be used for protecting the salivary gland from xerostomia caused by radiotherapy. It has also show protecting effects on intra-radiotherapy, but there are many problems waiting for study.
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PMID:[Radioprotective effects on head and neck tumors of amifostine--a broad-spectrum cytoprotection]. 1256 84

The effects of dose per fraction on the ability of amifostine exposure to elevate angiostatin levels in the serum of mice and to inhibit spontaneous metastases formation using the well-characterized murine Sa-NH sarcoma were investigated. Amifostine was administered intraperitoneally at doses of 50, 100, or 200 mg/kg every other day for 6 days to C3Hf/Kam mice until tumors reached an average size of 8 mm in diameter. Amifostine was again administered immediately following surgical removal of the tumor-bearing limbs by amputation, and then once more 2 days later. Nontumor-bearing control animals were treated using the same dosing and surgery schedules. The average number of pulmonary metastases per animal was determined for each experimental group. A significant reduction (P <.05) in the average number of pulmonary metastases was observed only in the group of animals exposed to a dose per fraction of 50 mg/kg. A dose of 100 mg/kg was less effective while 200 mg/kg had no effect on metastases formation in this study. The effects of amifostine exposure on serum levels of the angiogenesis inhibitor angiostatin were also determined using Western analysis. Correlating with the antimetastatic effect measured, exposure of animals to 50 mg/kg of amifostine resulted in a four-fold enhanced serum level of angiostatin above control levels. This phenomenon occurred in both tumor-bearing as well as nontumor-bearing animals. In contrast, a dose of 200-mg/kg amifostine administered intraperitoneally under these conditions had no measurable effect on angiostatin serum levels in this animal system. The enhanced ability of relatively low doses of amifostine to inhibit spontaneous metastases formation suggests that effective antimetastatic therapies with amifostine can be designed with minimal toxic side effects. While the dose responses for angiostatin production and metastases inhibition by amifostine are well correlated, the precise mechanism of action underlying these phenomena is unclear but is suggestive of a redox driven process(es).
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PMID:Antimetastatic effectiveness of amifostine therapy following surgical removal of Sa-NH tumors in mice. 1257 39

Amifostine (Ethyol; MedImmune Oncology, Gaithersburg, MD) is a radio- and chemoprotective agent currently in clinical use. Based on experimental data showing the potential for mucosal protection and additional information in animal studies showing rapid uptake of amifostine in the salivary glands along with effective radioprotection, several investigators have tested this drug in patients with head and neck squamous cell carcinoma (HNSCC) undergoing radiotherapy. The first evidence that amifostine, administered at 200 mg/m(2)/d intravenously before each radiotherapy session, could effectively protect salivary function in patients with HNSCC was provided by McDonald et al in a limited series of HNSCC patients. On the basis of these phase I results, an international multicenter phase III radiotherapy trial with or without amifostine was carried out by Brizel et al in a series of 315 patients with head and neck tumors showing a reduction in xerostomia with no suggestion of tumor protection. Additional data have been obtained in patients with HNSCC regarding the potential protective effect of amifostine on the duration and severity of radio-induced mucositis. This effect was reported in small, randomized studies of patients receiving intensive accelerated radiotherapy (Bourhis et al) or combined radiochemotherapy (Buntzel et al). In conclusion, the experience obtained to date in HNSCC patients treated with radiotherapy supports the selective cytoprotective activity of amifostine to minimize radiation effects while apparently not diminishing tumor control.
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PMID:Radioprotective effect of amifostine in patients with head and neck squamous cell carcinoma. 1257 47


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