Phase II trials of fosquidone (GR63178A) in carcinoma of the breast, head and neck, ovary and melanoma.

A total of 91 eligible patients with metastatic cancer have been treated in a series of phase II trials of the novel pentacyclic pyrroloquinone, fosquidone. Tumour types were breast (24), ovary (25), head and neck (21) and melanoma (21). All patients, except those with melanoma had received prior chemotherapy. The drug was given intravenously as a 20 min infusion, at the dose of 120 mg/m2 on days 1 to 5 of a 3 week cycle. Treatment was well tolerated; the only significant side-effects being mild headaches and generalised musculo-skeletal pains. Response was assessed after 2 cycles of therapy. Only one patient (with head and neck cancer) achieved an objective partial response, lasting 6 weeks. A total of 12 patients demonstrated stable disease for a median duration of 15 to 20 weeks. Using this schedule of administration, fosquidone has no significant antitumour activity in this group of tumours.     

Effect of cisplatin-containing chemotherapy on lithium serum concentrations.

OBJECTIVE: A case in which a possible cisplatin interference with lithium pharmacokinetics is evaluated. DATA SYNTHESIS: A 36-year-old woman with disseminated cervical cancer and multiple metastatic lesions in both kidneys was being treated with five courses of bleomycin, vindesine, mitomycin C, and cisplatin. The patient had also been taking lithium carbonate for the management of a manic-depressive disorder. Serum and urinary lithium concentrations were measured daily during the first course of chemotherapy and on a periodic basis during and between the consecutive courses. Lithium concentrations remained within the therapeutic range during the first course and increased later in association with deterioration of the patient's renal function secondary to progressive disease in both kidneys. This required dose adjustments of lithium. CONCLUSIONS: Lithium therapy should be guided by serial serum concentrations in such patients.     

A new peroxisomal disorder with fetal and neonatal adrenal insufficiency.

A boy with a new type of adrenoleukodystrophy is described. This was characterised by fetal and neonatal adrenal insufficiency, a neurological picture as seen in neonatal adrenoleukodystrophy, but with a normal number of peroxisomes in the liver and a peroxisomal dysfunction limited to the very long chain fatty acids and pristanic acid.     

Feasibility study of high-dose carboplatin and etoposide in the salvage treatment of testicular cancer.

Eleven patients with testicular cancer, either relapsing after or refractory to cisplatin-based chemotherapy, underwent salvage chemotherapy with high-dose carboplatin (800 mg/m2 on day 1) and high-dose etoposide (500 mg/m2 on days 1, 3 and 5). A total of 21 courses were administered. The major toxicity consisted of profound myelosuppression. There were two toxic deaths, both caused by infection during neutropenia. Bone marrow recovery was usually complete around day 26 (range 19-129). Other toxicities included mild mucositis, nausea and vomiting, and alopecia. No significant neurotoxicity or hearing loss were observed and only one patient had a moderate decrease in renal function. Nine of ten evaluable patients responded, with one complete remission, 6 partial remissions with normalization of tumor markers, and two partial remissions with over one log decrease of tumor markers. The duration of these remissions was not evaluable, since only three evaluable and responding patients did not receive additional therapy after HD-CE. All three relapsed after discontinuing chemotherapy. HD-CE has activity in relapsing or refractory testicular cancer and can be administered without bone marrow support. The regimen may thus be suitable to be used as a remission induction regimen prior to consolidation with intensive chemotherapy and autologous bone marrow transplantation.     

Elongation of very long-chain fatty acids is enhanced in X-linked adrenoleukodystrophy

X-linked adrenoleukodystrophy (X-ALD) is a progressive neurodegenerative disorder characterized by the accumulation of saturated and mono-unsaturated very long-chain fatty acids (VLCFA) and reduced peroxisomal VLCFA beta-oxidation activity. In this study, we investigated the role of VLCFA biosynthesis in X-ALD fibroblasts. Our data demonstrate that elongation of both saturated and mono-unsaturated VLCFAs is enhanced in fibroblasts from patients with peroxisomal beta-oxidation defects including X-ALD, and peroxisome biogenesis disorders. These data indicate that enhanced VLCFA elongation is a general phenomenon associated with an impairment in peroxisomal beta-oxidation, and not specific for X-ALD alone. Analysis of plasma samples from patients with X-ALD and different peroxisomal beta-oxidation deficiencies revealed increased concentrations of VLCFAs up to 32 carbons. We infer that enhanced elongation does not result from impaired peroxisomal beta-oxidation alone, but is due to the additional effect of unchecked chain elongation. We demonstrate that elongated VLCFAs are incorporated into complex lipids. The role of chain elongation was also studied retrospectively in samples from patients with X-ALD previously treated with "Lorenzo's oil." We found that the decrease in plasma C26:0 previously found is offset by the increase of mono-unsaturated VLCFAs, not measured previously during the trial. We conclude that evaluation of treatment protocols for disorders of peroxisomal beta-oxidation making use of plasma samples should include the measurement of saturated and unsaturated VLCFAs of chain lengths above 26 carbon atoms. We also conclude that chain elongation offers an interesting target to be studied as a possible mode of treatment for X-ALD and other peroxisomal beta-oxidation disorders.     

Analysis of very long-chain fatty acids using electrospray ionization mass spectrometry

Elevated levels of very long-chain fatty acids (VLCFA) in plasma and tissues are the biochemical hallmark for patients with X-linked adrenoleukodystrophy (X-ALD). Current methods for the determination of VLCFA levels are laborious and time-consuming. We describe a rapid and easy method using electrospray ionization mass spectrometry (ESI-MS) with deuterated internal standards. VLCFA are hydrolyzed, extracted, and quantified in less than 4h. This includes 2h of hydrolysis and 4min of quantification. We validated the method by analyzing 60 plasma samples from controls and patients with X-ALD or Zellweger syndrome using both the ESI-MS protocol and an established method for VLCFA analysis using gas chromatography (GC). The C26:0 concentrations determined with ESI-MS in plasma and fibroblasts of X-ALD patients are in good agreement with those reported previously for GC and GC-MS. Besides saturated straight chain VLCFA, we also determined the concentrations of the mono-unsaturated VLCFA C24:1 and C26:1 and established that while C24:1 levels are not elevated, C26:1 levels are elevated in both plasma and fibroblasts from X-ALD patients.     

Mutations of OCTN2, an organic cation/carnitine transporter, lead to deficient cellular carnitine uptake in primary carnitine deficiency

Systemic primary carnitine deficiency (CDSP, OMIM 212140) is an autosomal recessive disease characterized by low serum and intracellular concentrations of carnitine. CDSP may present with acute metabolic derangement simulating Reye's syndrome within the first 2 years of life. After 3 years of age, patients with CDSP may present with cardiomyopathy and muscle weakness. A linkage with D5S436 in 5q was reported in a family. A recently cloned homologue of the organic cation transporter, OCTN2, which has sodium-dependent carnitine uptake properties, was also mapped to the same locus. We screened for mutation in OCTN2 in a confirmed CDSP family. One truncating mutation (Trp132Stop) and one missense mutation (Pro478Leu) of OCTN2 were identified together with two silent polymorphisms. Expression of the mutant cDNAs revealed virtually no uptake activity for both mutations. Our data indicate that mutations in OCTN2 are responsible for CDSP. Identification of the underlying gene in this disease will allow rapid detection of carriers and postnatal diagnosis of affected patients.