Other tyrosine kinase inhibitors with anti-angiogenic effects, such as SU5416 (a VEGFR inhibitor) and SU6668 (an inhibitor of VEGF, fibroblast growth factor, and platelet-derived growth factor receptors), also enhance the anti-tumour effects of fractionated irradiation independent of drug sequencing (Ning et al, 2002). The gene discussed is KDR; the disease is neoplasm.