The meaningful role of tumour microenvironment in determining the complex plot of signalling among normal and cancer cells supports the pharmacogenetic approach, in the attempt to focus on the contribution of the genetic background of the host to mechanisms of intrinsic or acquired resistance to the anti-angiogenic drugs, for instance by modulating the secretion of proangiogenic factors (e.g., VEGF) or soluble forms of their receptors (e.g., sVEGFR-2; Pasqualetti et al, 2007). Here, VEGFA is linked to cancer.