Clinical significance of vascular endothelial growth factor [VEGF] in sera of patients with pediatric malignancies

Angiogenesis is essential for solid tumor growth. It is induced by tumor cells through stimulatory angiogenic peptides, one such peptide is vascular endothelial growth factor [VEGF]. The ultimate aim of the work is to investigate the possible role of VEGF as an early biomolecule involved in the progression of pediatric malignant tumors with high metastatic potential. Forty-five pediatric patients were studied. They included four groups with malignant solid tumors suffering from Ewing's sarcoma, osteosarcoma, neuroblastoma and rhabdomyosarcoma. In addition, a healthy control group including fifteen age and sex matched children was included in the study. Serum VEGF levels were determined by ELISA technique. The level of VEGF was significantly higher in all types of solid tumors compared to normal healthy children. The mean values obtained for patients and controls were 429.44 +/- 258.55 pg/ml and 79.36 +/- 63.81 pg/ml, respectively. No significant difference was detected in the level of VEGF among males and females. Also, no statistically significant difference was detected among the different types of malignant tumors. However, a marked significant difference was elucidated between metastatic and non-metastatic cancer patients, the values recorded were 753.33 +/- 173.64 pg/ml and 267.5 +/- 75.54 pg/ml, respectively [p <0.001]. Furthermore, the results showed that 207 pg/ml of serum level of VEGF is the optimal cutoff value [mean +/- 2 SD of control] with sensitivity of 87% and specificity of 100%. Using the receiver operating characteristic [ROC] curve analysis, the area under the curve [0.917] indicated the validity of using serum VEGF level in the diagnosis of all different types of pediatric malignant solid tumors with high potentiality to metastasis. VEGF is an angiogenic stimulatory peptide. Its serum level colud be a reliable marker in assessing pediatric malignancies with high metastatic potentials

Folic acid, vitamin B12 and vitamin B12 binding proteins in patients with neuroblastoma.

Serum vitamin B12, serum and red cell folate and serum vitamin B12 binding proteins were determined in 18 patients with neuroblastoma, with ages ranging from 8 months to 14 years. A mean value of serum vitamin B12 level was slightly but not significantly lower than that of the normal subjects but all of them had serum vitamin B12 levels over 150 pg/ml. There was no relationship between serum vitamin B12 levels and hemoglobin, hematocrit or white cells. Transcobalamin I (TCI) was significantly increased resulting in slightly elevated UBBC and normal TBBC levels in these patients. This could be a compensatory mechanism for the low serum vitamin B12 by increasing the unsaturated vitamin B12 binding capacity of TCI. All these findings indicated that the status of vitamin B12 in patients with neuroblastoma was within the normal limits. Treatment of neuroblastoma by giving a high dose of vitamin B12 would therefore not give any direct therapeutic effect. Both serum and red cell folate concentrations were significantly lower in the group of patients. As only 2 out of 18 patients had low serum folate and none of them had red cell folate lower than the lower limit of normal subjects; therefore these patients were only in the state of negative folate balance.