Pediatric neurofibrosarcoma.

BACKGROUND/PURPOSE: Neurofibrosarcoma is rare in children, and the natural history and prognostic factors are not well described. The authors present a 57-year review of their experience. METHODS: The charts of children with neurofibrosarcoma were reviewed retrospectively. Statistical analysis was performed using the Chi2 and unpaired t tests. RESULTS: From 1944 to 2001, 38 patients under the age of 21 were diagnosed with neurofibrosarcoma. Twenty-two were boys. The average age at diagnosis was 13.8 years (range, 3 to 19.9 years). Nineteen patients (50%) had neurofibromatosis. The tumor site was as follows: extremity, 19 patients; trunk, 9 patients; head and neck, 7 patients; and retroperitoneum, 3 patients. The average tumor size was 10 cm. The margins after resection were as follows: grossly positive, 9; microscopically positive, 5; negative, 21; and unknown, 3. Patients with positive margins had a 22% survival rate, whereas those with negative or unknown margins had a 34% survival rate. Thirty-two patients achieved a complete response, 2 a partial response, and 4 progressed while on therapy. Twenty-six patients relapsed after a complete response (11 local, 10 distant, 5 both). Of the 15 patients with a distant relapse, 73% (11) relapsed in the lung. Twelve (32%) patients survived with an average follow-up of 14 years (range, 0.3 to 28 years). Nine patients were treated with chemotherapy, 9 with radiation, and 9 with both chemotherapy and radiation. Outcome was not significantly affected by gender, presence of neurofibromatosis, site, margin, or use of adjuvant therapy. CONCLUSION: Neurofibrosarcoma remains a rare disease in children with insufficient contemporary numbers to assess efficacy of therapy. Prognosis remains poor with a high incidence of relapse, particularly in the lungs, suggesting that more aggressive therapies to control both local and distant relapses are needed.

Regulation of CD36 expression in human melanoma cells.

BACKGROUND: CD36 is a suspected facilitator of long chain fatty acid transport and as a thrombospondin (TSP) receptor, thereby being implicated in cell proliferation, angiogenesis and tumor metastasis. The human amelanotic melanoma cell line, C32, is known to express CD36 and has been as a model for studying TSP binding. PURPOSE: The purpose of this study was to investigate the regulation of CD36 expression in the C32 cell line. METHOD: C32 cells were treated with 12-O-tetradecanoylphorobol-13-acetate (TPA)(10 microM), insulin (174 nM), ibuprofen (0.3 mM) and oleic acid. CD36 mRNA levels were determined by Northern Blot analysis using human CD36 cDNA probe. Western blot analysis utilized the human anti-CD36 antibody. Protein and mRNA concentration was determined by autoradiography, densitometry and NIH image software. Statistical analysis was by Student's t-test with P < 0.05 considered significant. RESULTS: CD36 mRNA levels were decreased 2.2 fold in C32 cells treated with TPA (p < 0.05) compared to control cells. Insulin treated cells showed a 30% increase (p < 0.05) in CD36 mRNA levels. Ibuprofen, a regulator of peroxisomal proliferation activated receptor (PPAR) alpha, was found to increase CD36 protein levels by 50% (p < 0.05). Oleic acid had no effect on CD36 mRNA or protein levels. CONCLUSION: The finding that the tumor promoter TPA significantly decreases CD36 mRNA levels, while insulin and ibuprofen increase CD36 expression, may have important implications in tumor biology. The regulation of CD36 expression in tumor cells may play an important role in tumor growth, metastasis and angiogenesis.