Reference intervals for circulating angiogenic cytokines.

BACKGROUND: The levels of angiogenic cytokines are important in the definition of baseline characteristics of cancers and to predict patient prognosis; however, the reference intervals for angiogenic cytokines have received only limited attention. Herein, we obtained reference intervals for angiogenic cytokines, including vascular endothelial growth factor (VEGF), hepatocyte growth factor, basic fibroblast growth factor, interleukin-6, vascular endothelial growth factor receptor 1 and vascular endothelial growth factor receptor 2. METHODS: We measured these materials in serum, plasma and urine of 131 controls, according to the guidelines of the Clinical and Laboratory Standards Institute. We analyzed the association between angiogenic cytokine levels and other laboratory parameters and explored whether polymorphisms in angiogenic cytokine genes affect the levels of cytokines. RESULTS/CONCLUSIONS: These data allowed us to construct reference intervals for angiogenic cytokines, and we also observed that concentrations of angiogenic cytokines generally do not vary with genotype or haplotype. An exception was serum VEGF concentration; this level was marginally affected by the -1154 VEGF polymorphism.