Administration of Ethyol (amifostine) to a child with medulloblastoma to ameliorate hematological toxicity of high dose carboplatin

Prevention and restoration of hearing loss associated with the use of cisplatin

Background. Cisplatin is a well known platinum-based chemotherapeutic agent used for the treatment of various malignant tumours. A frequent side effect of cisplatin therapy is ototoxicity. Unfortunately, currently there are no available treatments. Material and Methods. Experimental, clinical studies and reviews published between 2004 and 2014 in the English medical literature concerning ototoxicity were selected using Medline, PubMed, and Google Scholar databases. Inclusion criteria were cisplatin-induced ototoxicity and therapy aimed at preventing or curing this disorder. Molecular mechanisms and clinical, audiological, and histological markers of cisplatin-induced ototoxicity are described. Moreover, experimental and clinical strategies for prevention or treatment of hearing loss were also reviewed. Results and Discussion. Experimental studies demonstrate a wide range of otoprotective molecules and strategies efficient against cisplatin-induced hearing loss. However, only dexamethasone proved a slight otoprotective effect in a clinical study. Conclusion. Further research must be completed to bring future therapeutic options into clinical setting.

A pilot study of addition of amifostine to melphalan, carboplatin, etoposide, and cyclophosphamide with autologous hematopoietic stem cell transplantation in pediatric solid tumors-A pediatric blood and marrow transplant consortium study

Limited information is available regarding the use of amifostine in pediatric hematopoietic stem cell transplant (HSCT) patients. Melphalan, carboplatin, etoposide +/- cyclophosphamide is a commonly used preparatory regimen in pediatric solid tumor HSCT. Therefore, we decided to determine the feasibility of the addition of amifostine (750 mg/m b.i.d. x 4 d) to melphalan (200 mg/m), carboplatin (1200 mg/m), and etoposide (800 mg/m) (level 1) and escalating doses of cyclophosphamide (3000 mg/m and 3800 mg/m, levels 2 and 3, respectively) followed by autologous HSCT. Thirty-two patients with a variety of pediatric solid tumors were studied. Seventeen patients were accrued at level 1, 9 at level 2, and 6 at level 3. Major toxicities during the administration of the preparatory regimen were hypocalcemia, emesis, and hypotension. Hypocalcemia required aggressive calcium supplementation during the conditioning phase. No dose limiting toxicities were encountered at level 3. Amifostine at 750 mg/m b.i.d. for 4 days can be administered with a double alkylator regimen consisting of melphalan (200 mg/m), cyclophosphamide (up to 3800 mg/m), carboplatin (1200 mg/m), and etoposide (800 mg/m) with manageable toxicities.

Daily subcutaneous amifostine administration during irradiation of pediatric head and neck cancers

Five pediatric patients with head and neck cancers were treated with radiotherapy. Subcutaneous injections of 200 mg flat dose amifostine were given 30 min prior to radiation fractions. A total of 129 amifostine injections were done. Grade 3 nausea occurred three times and emesis only once. Hypotension, hypocalcemia, or allergic reactions following injections were not recorded. No grade 3 or 4 mucosal or skin reactions occurred. After 16 months, all patients were alive and disease-free. There were no grade 3 or 4 side effects of radiotherapy on follow-up. Further studies with more patients are required to determine the role of amifostine in pediatric radiation oncology, but these data should contribute to the clinical spectrum of amifostine use in pediatric oncology.

Uptake and metabolism of novel biodegradable poly (glycerol-adipate) nanoparticles in DAOY monolayer

A useful route for the development of antitumour therapies is by creating improved methods for delivering therapeutic agents to tumour cells or subcellular compartments and increasing retention of drugs within target cells. In this study, we have characterized nanoparticle (NP) uptake and metabolism by DAOY cells, a human medulloblastoma cell line. NPs were formed from a novel polymer, poly (glycerol-adipate) (PGA), containing Rhodamine B Isothiocyanate (RBITC) as a fluorescent marker. It was observed that the cellular uptake of NPs depends on the incubation time and the concentration of NPs in the culture medium. The studies of retention and metabolism of NPs within cells indicated that 1) faster degradation of NPs within cells compared with that in cell culture medium in vitro; 2) a small fraction of NPs were recycled back to the outside of cell, whereas most NPs entered endosomes and lysosomes; and 3) recycled NPs were re-taken up in the following 2 h incubation time. These studies thus suggested that PGA NPs could be used for localising therapeutic agents into cells, and could provide prolonged drug effects because of their long sustained release in physiological conditions and their rapid release when taken up into cells.

Intensified platinum therapy is an ineffective strategy for improving outcome in pediatric patients with advanced hepatoblastoma

PURPOSE

The INT-0098 Intergroup Liver Tumor Study demonstrated no statistically significant differences in event-free and overall survival between patients randomized to treatment with either cisplatin + fluorouracil + vincristine (C5V) or cisplatin + doxorubicin. Results from this and other therapeutic trials suggested that cisplatin was the most active agent against hepatoblastoma. To increase the platinum dose-intensity, a novel regimen was developed alternating carboplatin and cisplatin (CC) every 2 weeks. The P9645 study was designed to compare the risk of treatment failure for patients with stage III/IV hepatoblastoma randomized to either C5V or CC.

METHODS

C5V was given according to INT-0098 and CC consisted of carboplatin at 700 mg/m2 on day 0 (560 mg/m2 after two cycles) followed by cisplatin 100 mg/m2 on day 14. Granulocyte colony-stimulating factor was used after each CC cycle. All patients received four to six cycles of chemotherapy.

RESULTS

From the time the study was opened until the time that random assignment was halted, 56 patients received CC and 53 patients received C5V. The 1-year event-free survival was 37% for patients receiving CC and 57% for those receiving C5V (P = .017). Patients randomly assigned to CC required more blood product support. As a result of a semiannual review by the Children's Oncology Group Data and Safety Monitoring Committee, random assignment was discontinued after 3 years of enrollment because the projected improvement in long-term outcome associated with CC was statistically excluded as a possible outcome of this trial.

CONCLUSION

Intensification of therapy by alternating platinum analogs increased the risk of adverse outcome in children with unresectable or metastatic hepatoblastoma.

Amifostine does not protect against the ototoxicity of high-dose cisplatin combined with etoposide and bleomycin in pediatric germ-cell tumors: a Children's Oncology Group study

BACKGROUND

High-dose cisplatin combined with etoposide and bleomycin (HDPEB) improves event-free survival (EFS) in advanced pediatric germ-cell tumors (PGCT), but has significant ototoxicity. Amifostine appears to protect against toxicity. The authors combined amifostine with HDPEB and evaluated the efficacy and toxicity, specifically whether ototoxicity decreased.

METHODS

Eligibility criteria included age < 15 years and unresectable Stage III/IV extracranial, extragonadal PGCT. Patients received bleomycin 15 IU/m(2) on Day 1, then etoposide 100 mg/m(2) per day, amifostine 825 mg/m(2) per day, and cisplatin 40 mg/m(2)per day on Days 1-5, intravenously. The cycles were repeated every 3-4 weeks with imaging evaluation after 4 cycles. Patients with residual radiographic abnormalities underwent resection. Patients with residual tumor received two additional HDPEB cycles. Hearing evaluations were required at diagnosis and after two and four cycles. Audiologic results were reviewed and compared with historical controls treated with HDPEB.

RESULTS

Twenty-five eligible patients were enrolled between April 2000 and April 2002. Their median age was 1.6 years (range, 0.64-13.9 years), 17 patients were female, 11 had metastases, and 24 had a yolk sac carcinoma component histologically. Primary sites included sacrococcygeal area/pelvis (n = 15), vagina (n = 5), and other (n = 5). Two-year EFS and overall survival were 83.5% +/- 12.8% and 85.6% +/- 12.3%, respectively. Eight patients were removed from the study (four had progressive disease/disease recurrence and four had ototoxicity). Grade 3/4 toxicities included neutropenia (n = 20), thrombocytopenia (n = 14), electrolyte imbalances (n = 14), and gastrointestinal toxicity (n = 12). Twenty-four of 25 patients received hearing evaluations, and 75% had significant hearing loss.

CONCLUSIONS

Amifostine did not protect against HDPEB-associated ototoxicity.

Properties and biological activities of thioredoxins

The mammalian thioredoxins are a family of small (approximately 12 kDa) redox proteins that undergo NADPH-dependent reduction by thioredoxin reductase and in turn reduce oxidized cysteine groups on proteins. The two main thioredoxins are thioredoxin- 1, a cytosolic and nuclear form, and thioredoxin-2, a mitochondrial form. Thioredoxin-1 has been studied more. It performs many biological actions including the supply of reducing equivalents to thioredoxin peroxidases and ribonucleotide reductase, the regulation of transcription factor activity, and the regulation of enzyme activity by heterodimer formation. Thioredoxin-1 stimulates cell growth and is an inhibitor of apoptosis. Thioredoxins may play a role in a variety of human diseases including cancer. An increased level of thioredoxin-1 is found in many human tumors, where it is associated with aggressive tumor growth. Drugs are being developed that inhibit thioredoxin and that have antitumor activity.

Properties and biological activities of thioredoxins

The mammalian thioredoxins are a family of small (approximately 12 kDa) redox proteins that undergo NADPH-dependent reduction by thioredoxin reductase and in turn reduce oxidized cysteine groups on proteins. The two main thioredoxins are thioredoxin-1, a cytosolic and nuclear form, and thioredoxin-2, a mitochondrial form. Thioredoxin-1 has been studied more. It performs many biological actions including the supply of reducing equivalents to thioredoxin peroxidases and ribonucleotide reductase, the regulation of transcription factor activity, and the regulation of enzyme activity by heterodimer formation. Thioredoxin-1 stimulates cell growth and is an inhibitor of apoptosis. Thioredoxins may play a role in a variety of human diseases including cancer. An increased level of thioredoxin-1 is found in many human tumors, where it is associated with aggressive tumor growth. Drugs are being developed that inhibit thioredoxin and that have antitumor activity.

Preclinical and clinical aspects on the use of amifostine as chemoprotector in neuroblastoma patients

BACKGROUND

In several studies in adults, amifostine (WR-2721) and its active metabolite WR-1065 have shown protection against myelo- and nephrotoxicity of chemotherapeutic agents without compromising cytotoxic efficacy to the tumor.

PROCEDURE

In the present study, the effect of amifostine and WR-1065 on neuroblastoma tumor growth and its protective potential for hematotoxicity were investigated. Neither amifostine nor WR-1065 reduced the cytotoxic effect of six drugs commonly used for this tumor when tested on neuroblastoma cells in vitro.

RESULTS

In mice carrying human xeno-transplanted neuroblastoma, tumor growth and antitumor activity of chemotherapy were unaffected by amifostine. In addition, hematotoxicity of alkylators was relieved in some cases. In patients with neuroblastoma, amifostine only slightly reduced bone marrow toxicity and was highly emetogenic.

CONCLUSIONS

Therefore, amifostine warrants further investigation before its widespread clinical use in the treatment of children with neuroblastoma.

Cytoprotection in the treatment of pediatric cancer: review of current strategies in adults and their application to children

BACKGROUND

The protection of patients from the acute and/or chronic toxicity of antineoplastic therapy has become a major concern of oncology centers around the world. However, most of the effort has been directed toward the adult population, and limited studies have been performed in the group that may gain the most from such strategies, namely, children.

PROCEDURES

The MedLine and CancerLit databases were surveyed, and the relevant biomedical literature on cytoprotection during antineoplastic treatment was analyzed.

RESULTS

Cytotoxicity from antineoplastic therapy customarily is addressed by altering dosing schedules, a technique that can seriously impact the efficacy of the therapy. Colony stimulating factors have been used posttherapy to stimulate recovery from neutropenia, and various agents have been proposed as pretherapy cytoprotectors. Trials in adults have produced mixed results, and, to date, only amifostine and dexrazoxane have been approved as cytoprotectors for very narrow indications. Few trials have been performed in children, although these patients often can look forward to long-term remission.

CONCLUSIONS

To prevent permanent toxicities from antineoplastic therapies that impact long-term pediatric survivors, the experience gained in adults should be extended more aggressively to children, and formal, randomized trials should be performed to determine the type of protection most suitable for the pediatric population.