Increased placental growth factor expression has been shown to correlate with CRC progression and a less favorable prognosis.[28] In vitro, aflibercept appeared to have greater potency and affinity than bevacizumab in blocking VEGF-A-induced activation of vascular endothelial growth factor receptor-1 and vascular endothelial growth factor receptor-2.[29] Chiron M et al[30] found that aflibercept had greater anti-tumor activity than bevacizumab. This evidence concerns the gene PGF and neoplasm.