Investigations over the last decade have established the essential role of growth factors and their receptors during angiogenesis. The biological significance of VEGF, EGF, and bFGF is mediated by their receptors, which belong to the family of tyrosine kinase receptors: Flt‐1 (VEGFR‐1), KDR (VEGFR‐2), EGFR, FGFR‐1, FGFR‐2, FGFR‐3, and FGFR‐4. Deeper understanding of the mechanism of activation of these growth factor receptors has allowed the development of a new pharmacological strategy aimed at controlling cancer cell proliferation. The results of a large body of preclinical as well as early clinical studies conducted suggest that targeting the growth factor receptors could represent a significant contribution to cancer therapy. Microsc. Res. Tech. 60:70–75, 2003. © 2002 Wiley‐Liss, Inc.