Angiogenesis and antiangiogenic agents in non-small cell lung cancer

Tumour angiogenesis is the result of the imbalance between a large number of mediators with angiogenic and antiangiogenic activity. It may be a very early process in vivo and it may follow different pathways in different organs. Moreover, different roles of angiogenic molecules have been observed in normal and neoplastic lung and striking differences between non-small cell lung carcinomas (NSCLC) and SCLC have been observed. Contradictory results are reported in the literature on the association of angiogenesis with poor prognosis in NSCLC. Among the currently available antiangiogenic therapies, the inhibitors of vascular endothelial growth factor (VEGF), and their receptor (VEGFR) and matrix metallo-proteinase (MMP), some antivascular agents and the antiangiogenic scheduling of chemotherapy are beginning to show clinical efficacy. The best use of the antiangiogenic therapies will probably be in presence of low tumour burdens and in association with chemotherapy. However, new surrogate markers of tumour response have to be defined.