Angiogenesis shifted from the avascular to vascular states is a key event for sustained tumor growth and cancer progression. Angiogenesis as a biological switch process is governed by numerous pro- and anti-angiogenic factors, including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGFb) and IL-6. The mechanism of action of each of these factors is different, as are their origin and the stimuli for their production. The angiogenic switch refers to the balance between pro- and anti- angiogenic factors. Therefore, profiling of these factors is critical to understanding angiogenesis. Signosis' Rat Angiogenesis ELISA Strip Profiling Assay allows simultaneously profiling 8 rat angiogenesis cytokines. The difference of these proteins between two samples can be determined through data comparison.