The EGF(R) and VEGF(R) Pathways as Combined Targets for Anti-Angiogenesis Trials in Cancer Therapy

In tumor biology both the EGF(R) and the VEGF(R) pathway are constitutively activated due to genetic abnormalities and ongoing tumor-associated hypoxia. In addition, both pathways can be activated by anticancer therapies such as chemotherapy and radiotherapy, which contributes to the resistance to these treatments. Moreover, VEGF modulates EGFR signaling and EGF induces VEGF activity. Therefore, both pathways are logical targets for therapy, and because of their parallel and reciprocal activation, dual inhibition of the EGF(R) and VEGF(R) signaling makes sense. In this chapter we discuss the possibilities for integrated anti-angiogenesis therapy directed at these two biological systems.