FGF2 and B-cell chronic lymphocytic leukemia: CLL cells can initiate neovascularization via the secretion of pro-angiogenic signals including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and angiopoietin-2 (Ang2), and inducing PKC-βII expression in endothelial cells which has been shown to be essential for the formation of new blood vessels [79,80,81,82].